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1.
Journal of Prevention and Treatment for Stomatological Diseases ; (12): 169-177, 2024.
Artigo em Chinês | WPRIM | ID: wpr-1006509

RESUMO

Objective@#To investigate the effects of electrochemically dealloying of Ti6Al4V abutments on human gingival fibroblasts (HGFs) and to provide experimental evidence for surface modification of implant abutments.@*Methods@#The samples were divided into an NC group (negative control, no other treatment on a smooth surface), an NM-1 group (nanomesh-1, electrochemical dealloying treatment in 1 mol/L NaOH 1 h on 2 V voltage), and an NM-2 group (nanomesh-2, electrochemical dealloying treatment in 5 mol/L NaOH 1 h on 2 V voltage). The surface morphologies of the samples and the adhesion of HGFs on the sample surfaces were observed with scanning electron microscopy (SEM). The surface hydrophilicities of the samples were measured with a contact angle measuring instrument. The proliferation of HGFs on the different samples were evaluated with CCK-8, and the expression of adhesion-related genes, including collagen Ⅰ (COL1A1), collagen Ⅲ (COL3A1), fibronectin 1 (FN1), focal adhesion kinase (FAK), vinculin (VCL), integrin α2 (ITGA2), and integrin β1 (ITGB1), on the different samples was measured with qRT-PCR. The expression of vinculin on the surfaces of HGFs was observed via confocal laser scanning microscopy (CLSM) after immunofluorescent staining. Collagen fiber secretion and syntheses of HGFs from different samples were evaluated via Sirius red staining.@*Results@#SEM revealed the formation of ordered and uniform three-dimensional mesh structures on the surfaces of the NM-1 and NM-2 groups, with grid diameters of approximately 30 nm for the NM-1 group and approximately 150 nm for the NM-2 group. Compared with that of the NC group, the water contact angles of the NM-1 group and NM-2 groups were significantly lower (P<0.000 1). Cell proliferation in the NM-1 group was significantly greater than that in the NC group (P<0.01). Moreover, there was no significant difference in the water contact angles or cell proliferation between the NM-1 group and the NM-2 group. SEM revealed that HGFs were adhered well to the surfaces of all samples, while the HGFs in the NM-1 and NM-2 groups showed more extended areas, longer morphologies, and more developed pseudopodia than did those in the NC group after 24 h. qRT-PCR revealed that the expression levels of the adhesion-related genes COL1A1, COL3A1, FN1, FAK and VCL in the NM-1 group were significantly greater than those in the NC and NM-2 groups (P<0.01). The expression of vinculin protein in the NM-1 group was the highest, and the number of focal adhesions was greatest in the NM-1 group (P<0.01). The results of Sirius red staining showed that the NM-1 group had the highest secretion and syntheses of collagen fibers (P<0.000 1).@*Conclusion@#The three-dimensional nanomechanical structure of Ti6Al4V modified by electrochemical dealloying promoted the adhesion, proliferation, collagen fiber secretion and syntheses of HGFs, and electrochemical dealloying of Ti6Al4V with a grid diameter of approximately 30 nm obviously promoted HGF formation.

2.
Journal of Traditional Chinese Medicine ; (12): 139-143, 2024.
Artigo em Chinês | WPRIM | ID: wpr-1005361

RESUMO

Based on the theory of ti (character, 体) and yong (function, 用) in mental illness, ZHAO Yonghou's clinical experience in staged differentiation and treatment of schizophrenia is summarized. According to the theory, the core disease location of schizophrenia is in the brain, which is closely related to the organs, qi, and blood. It is proposed to interpret the pathogenesis of schizophrenia from the perspective of “zang-fu organs-qi and blood-brain and spirit”, that is, dysfunction of the zang-fu organs, disharmony of qi and blood, and malnourishment of the brain ti lead to dysfunction of the spirit ti and yong. In clinical practice, treatment of schizophrenia can be divided into four stages, for which the method of treating ti and yong simultaneously is suggested. In the prodromal stage, Liuwei Dihuang Decoction combined with Sini San (六味地黄汤合四逆散) with modifications is used to nourish the kidney and boost marrow, soothe the liver and rectify the spleen. For acute exacerbation with binding of phlegm and heat syndrome, Zhaoshi Yikuang Decoction (赵氏抑狂汤) with modifications is used to clear heat and dispel phlegm, awaken the brain and calm the mind. For phlegm-heat damaging yin pattern, Mengshi Guntan Pill combined with Zengye Decoction (礞石滚痰丸合增液汤) with modifications is used to clear heat and dispel phlegm, enrich yin and calm the mind. For the chronic treatment stage, Yudian Decoction (愈癫汤) with modifications is used to disperse phlegm and dissolve stasis, move qi and awaken the mind. For the rehabilitation and regulation stage, Shenan Pill (神安丸) with modifications is used to boost qi and nourish yin, and tranquilize the mind.

3.
Dental press j. orthod. (Impr.) ; 29(2): e2423282, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS, BBO | ID: biblio-1557696

RESUMO

ABSTRACT Objective: This study aimed to compare the insertion torque (IT), flexural strength (FS) and surface alterations between stainless steel (SS-MIs) and titanium alloy (Ti-MIs) orthodontic mini-implants. Methods: Twenty-four MIs (2 x 10 mm; SS-MIs, n = 12; Ti-MIs, n = 12) were inserted on artificial bone blocks of 20 lb/ft3 (20 PCF) and 40 lb/ft3 (40 PCF) density. The maximum IT was recorded using a digital torque meter. FS was evaluated at 2, 3 and 4 mm-deflection. Surface topography and chemical composition of MIs were assessed by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). General linear and mixed models were used to assess the effect of the MI type, bone density and deflection on the evaluated outcomes. Results: The IT of Ti-MIs was 1.1 Ncm greater than that obtained for the SS-MIs (p= 0.018). The IT for MIs inserted in 40 PCF test blocks was 5.4 Ncm greater than that for those inserted in 20 PCF test blocks (p < 0.001). SS-MIs inserted in higher density bone (40 PCF) had significantly higher flexural strength than the other groups, at 2 mm (98.7 ± 5.1 Ncm), 3 mm (112.0 ± 3.9 Ncm) and 4 mm (120.0 ± 3.4 Ncm) of deflection (p< 0.001). SEM evidenced fractures in the Ti-MIs. EDS revealed incorporation of 18% of C and 2.06% of O in the loaded SS-MIs, and 3.91% of C in the loaded Ti-MIs. Conclusions: Based on the findings of this in vitro study, it seems that SS-MIs offer sufficient stability and exhibit greater mechanical strength, compared to Ti-MIs when inserted into higher density bone.


RESUMO Objetivo: O objetivo deste estudo foi comparar o torque de inserção (TI), a resistência flexural (RF) e as alterações de superfície em mini-implantes ortodônticos de aço inoxidável (MIs-Ai) e de liga de titânio (MIs-Ti). Métodos: Vinte e quatro MIs (2 x 10 mm; MIs-Ai, n = 12; MIs-Ti, n = 12) foram inseridos em blocos de osso artificial de densidades de 20 lb/ft3 (20 PCF) e 40 lb/ft3 (40 PCF). O torque máximo de inserção foi registrado por meio de um torquímetro digital. A resistência flexural foi avaliada nas deflexões de 2, 3 e 4 mm. Topografia de superfície e composição química dos MIs foram avaliadas por Microscopia Eletrônica de Varredura (MEV) e Espectroscopia de Energia Dispersiva de Raios X (EDS). Modelos lineares gerais e mistos foram utilizados para avaliar o efeito do tipo de MI, da densidade óssea e da deflexão nos desfechos avaliados. Resultados: O TI dos MIs-Ti foi 1,1 Ncm maior do que o obtido para os MIs-Ai (P = 0,018). O TI para MIs inseridos em blocos de teste de 40 PCF foi 5,4 Ncm maior do que para aqueles inseridos em blocos de teste 20 PCF (p < 0,001). MIs-Ai inseridos em osso de maior densidade (40 PCF) apresentaram resistência flexural significativamente maior do que outros grupos, em deflexões de 2 mm (98,7 ± 5,1 Ncm), 3 mm (112,0 ± 3,9 Ncm) e 4 mm (120,0 ± 3,4 Ncm) (p < 0,001). A MEV evidenciou fraturas nos MIs-Ti. A EDS revelou incorporação de 18% de C e 2,06% de O nos MIs-Ai e 3,91% de C nos MIs-Ti, ambos submetidos a testes mecânicos. Conclusões: Com base nos resultados desse estudo in vitro, os MIs-Ai aparentam oferecer adequada estabilidade e maior resistência mecânica, em comparação aos MIs-Ti, quando inseridos em osso de maior densidade.

4.
Rev. Costarric. psicol ; 42(2): 205-224, jul.-dic. 2023. graf
Artigo em Espanhol | LILACS, SaludCR | ID: biblio-1559039

RESUMO

Resumen En la actualidad, la violencia psicológica (VP) en las relaciones de noviazgo es un fenómeno prevalente. El objetivo de este estudio fue analizar y comprender las redes de significados acerca de la VP en el noviazgo según los estudiantes de la Facultad de Psicología de la Universidad del Aconcagua a través del software ATLAS.ti. Es una investigación cualitativa, estudio descriptivo, con un diseño fenomenológico en una muestra intencional de estudiantes universitarios argentinos. Participaron un total de 153 estudiantes de 1º y 4º año, de ambos sexos, con una edad promedio de 22 años (rango de 18 a 25) que hubieran mantenido alguna relación de noviazgo. La técnica utilizada fue el grupo focal y se usó el software ATLAS.ti para el análisis de los datos. Se obtuvieron cuatro líneas temáticas: Diferencias entre VP y violencia física, Emociones de la VP en el noviazgo, Conductas en la VP en el noviazgo y Consecuencias en futuras relaciones. Se concluye que la VP es considerada como más dañina, que pasa desapercibida y se naturaliza. Angustia, culpa y miedo son algunas de las emociones que provoca la VP, y la manipulación, el maltrato y el control algunas de las conductas que manifiestan VP en el noviazgo. Como consecuencias en futuras relaciones, destacan el miedo y el establecimiento de nuevas relaciones de pareja similares. Urge diseñar programas de prevención temprana para minimizar el impacto de sus consecuencias, fomentando el amor y el respeto en las relaciones entre jóvenes.


Abstract Introduction: Psychological violence (PSV) in dating relationships is currently prevalent. Objective: Analyze and understand the networks of meanings of PSV in the dating of students from the Faculty of Psychology of the University of Aconcagua by means of the ATLAS.ti software. Method: Qualitative research, descriptive study, with a phenomenological design in an intentional sample of university students from Argentina. A total of 153 students from 1st and 4th year, of both sexes, with an average age of 22 years (range of 18 to 25) who would have had some relationship. The instrument used was the focus group and the ATLAS.ti software was used to analyze the data. Results: Four thematic lines were obtained: Differences between PSV and physical violence, Emotions of PSV in courtship, PSV behaviors in in courtship and Consequences in future relationships. Conclusions: PSV was considered more harmful, unnoticed, and naturalized. Distress, guilt, and fear are some of the emotions that PSV provokes; and manipulation, abuse, and control are some of its behaviors. As consequences in future relationships the fear of the establishing new relationships with a similar partner stands out. There is an urgent need to design early prevention programs to minimize the impact of their consequences, fostering love and respect in relationships between young people.


Assuntos
Humanos , Violência por Parceiro Íntimo/psicologia , Argentina , Comportamento Social , Estudantes , Emoções
5.
Gac. méd. boliv ; 46(1)2023.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1448304

RESUMO

Objetivo: evaluar la precisión de los distintos puntos de corte del score Bethesda de la BAAF, en comparación con el estudio histopatológico para el diagnóstico de patología tiroidea. Métodos: estudio cuantitativo, observacional, de tipo transversal, analítico para la evaluación de pruebas diagnósticas. Incluyó 293 pacientes con patología tiroidea sugestiva de cáncer, que acudieron a Servicio de Cirugía General del Hospital Obrero N° 2 de la Caja Nacional de Salud, durante el periodo de 2019-2022. Se realizó un muestreo no aleatorizado por conveniencia que incluía a todos los pacientes disponibles. Resultados: se afirma la correlación entre las dos variables estudiadas, es decir, entre el puntaje del score Bethesda y el reporte del estudio histopatológico, con un intervalo de confianza (IC) del 95%. Conclusiones: se demuestra que la BAAF tiene alta especificidad en el diagnóstico de cancer de tiroides con reporte Bethesda V y VI, por el contrario, reportes Bethesda menores II, III y IV, descartan el diagnóstico.


Objective: to evaluate the precision of the different cut-off points of the BAAF Bethesda score in comparison with the histopathological study for the diagnosis of thyroid pathology. Methods: quantitative, observational, cross-sectional, analytical study for the evaluation of diagnostic tests. It included 293 patients with thyroid disease suggestive of cancer, who attended the General Surgery Service of Hospital Obrero No. 2 of the National Health Fund, during the period 2019-2022. Non-randomized convenience sampling was performed that included all available patients. Results: the correlation between the two variables studied was confirmed, that is, between the Bethesda score and the histopathological study report, with a confidence interval (CI) of 95%. Conclusions: it is demonstrated that the BAAF has high specificity in the diagnosis of thyroid cancer with Bethesda reports V and VI, on the contrary, minor Bethesda reports II, III, and IV, rule out the diagnosis.

6.
Rev. adm. pública (Online) ; 57(2): e2022-0221, 2023. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1441091

RESUMO

Abstract The growing investments in information technology (IT) each year pushes public sector organizations to develop the ability to gather, integrate, and implement these resources to improve organizational processes. Public sector organizations have to be agile and flexible to meet society's dynamic demands. In this sense, IT management and creating an organizational environment facilitating innovation are crucial measures. These organizations must learn to cultivate IT capabilities and innovativeness to improve their performance and create public value. Thus, this study aims to identify the existing relationships between innovativeness, IT capabilities, IT reconfiguration capability, and organizational performance in the public sector. The research analyzed data from 254 Brazilian public organizations of the most diverse sizes and sectors using structural equation modeling (SEM). The results indicated that the ability to reconfigure IT must be listed among the organizations' IT capabilities. Also, the findings suggest that IT capabilities foster organizations' innovativeness, and IT capabilities and innovativeness positively impact the organizations' performance. The study contributes to knowledge of innovation and IT capabilities by testing theoretical propositions identified in the context of the private sector but insufficiently assessed in the public sector. Finally, the study points out ways for public managers to better prepare their institutions to face constantly changing environments.


Resumen En vista del creciente volumen de recursos invertidos anualmente en tecnología de la información, las organizaciones del sector público deben tener cada vez más la capacidad de reunir, integrar e implementar recursos de TI para satisfacer las necesidades de los procesos organizacionales. Además, a las organizaciones públicas se les exige cada vez más ser más ágiles y flexibles para poder atender las demandas dinámicas de las sociedades. En este sentido, las organizaciones públicas deben ser capaces de gestionar y aplicar adecuadamente los recursos informáticos de los que disponen, así como crear entornos organizativos que permitan y favorezcan el florecimiento de la innovación. Es decir, deben aprender a cultivar las capacidades de TI y la innovación, con el objetivo de cumplir mejor su misión y crear valor público. Así, el objetivo de este estudio es identificar las relaciones existentes entre la innovación, las capacidades de TI, la capacidad de reconfiguración de TI y el desempeño organizacional, en el contexto del sector público. Para ello, se analizaron datos de 254 organizaciones públicas brasileñas de los más diversos tamaños y sectores, utilizando un enfoque de ecuaciones estructurales (SEM). Los resultados indicaron que la capacidad de reconfigurar la TI debe figurar entre las capacidades de TI de las organizaciones públicas, así como que las capacidades de TI desempeñan un papel en el fomento de la innovación de las organizaciones y que ambas (capacidades de TI e innovación) tienen un impacto positivo en el desempeño de las organizaciones. Al contrastar proposiciones teóricas identificadas en el contexto del sector privado, pero insuficientemente evaluadas en el sector público, el estudio agrega un bloque en la construcción de conocimiento sobre la capacidad de innovación y las capacidades de TI, además de señalar caminos para los gestores públicos sobre cómo pueden hacer que sus instituciones estén mejor preparadas para enfrentar entornos en constante cambio.


Resumo Tendo em vista o crescente volume de recursos investidos em tecnologia da informação a cada ano, as organizações do setor público devem cada vez mais ter a capacidade de reunir, integrar e implementar recursos de TI, a fim de atender às necessidades dos processos organizacionais. Além disso, as organizações públicas são cada vez mais exigidas a serem mais ágeis e flexíveis para atender às demandas dinâmicas das sociedades. Nesse sentido, as organizações públicas devem ser capazes de administrar e aplicar adequadamente os recursos de TI de que dispõem, bem como criar ambientes organizacionais que permitam e estimulem o florescimento da inovação. Ou seja, devem aprender a cultivar as capacidades de TI e a inovação, com o objetivo de melhor cumprir sua missão e criar valor público. Assim, o objetivo deste estudo é identificar as relações existentes entre inovatividade, capacidades de TI, capacidade de reconfiguração de TI e desempenho organizacional, no contexto do setor público. Para tanto, dados de 254 organizações públicas brasileiras, dos mais diversos portes e setores, foram analisados por meio de uma abordagem de equações estruturais (SEM). Os resultados indicaram que a capacidade de reconfigurar TI deve ser listada entre as capacidades de TI das organizações públicas, bem como que as capacidades de TI desempenham um papel no fomento da inovação das organizações e que ambas (as capacidades de TI e a inovatividade) têm um impacto positivo no desempenho das organizações. Ao testar proposições teóricas identificadas no contexto do setor privado, mas insuficientemente avaliadas no setor público, o estudo acrescenta um bloqueio na construção do conhecimento sobre capacidade de inovação e capacidades de TI, além de apontar caminhos para gestores públicos sobre como eles podem tornar suas instituições mais bem preparadas para enfrentar ambientes em constante mudança.


Assuntos
Inovação Organizacional , Eficiência , Tecnologia da Informação
7.
Rev. venez. cir ; 76(1): 10-14, 2023. tab
Artigo em Espanhol | LILACS, LIVECS | ID: biblio-1552933

RESUMO

La comunidad científica se ha preocupado por cuantificar el volumen tiroideo según variables como sexo, edad y deficiencias de yodo asociadas, sin embargo, pese al uso globalizado de TI-RADS para estimación de riesgo de malignidad en la patología tiroidea, no existe suficiente información en relación a si el tamaño de la glándula guarda o no relación con esta escala. Objetivo: comparar el Volumen Tiroideo con TI-RADS en pacientes atendidos en la unidad de ecografía diagnóstica del Centro Clínico Naguanagua en el período enero 2022 - enero 2023. Métodos: estudio observacional-descriptivo de nivel comparativo, con diseño transversal y prospectivo. Muestra no probabilística censal, abarcando la totalidad de los pacientes a los cuales se les efectuó ecografía tiroidea en el período establecido. Se efectuó un registro en cuanto a la cuantificación del volumen de: lóbulo tiroideo derecho, lóbulo tiroideo izquierdo y total de tiroides, TI-RADS, edad y sexo del paciente. Se utilizó el estadístico ANOVA y se empleó el programa Statistical® de licencia libre. Resultados: muestra de 126 pacientes, con edad promedio de 51,71 años ± 1,44, mediana de 53 años. Cuando se comparó el Volumen Total de Tiroides con TI-RADS, se constató que el mayor promedio lo registraron aquellos pacientes clasificados como 4B (p <0,05). Conclusión: aun cuando se registran mayores promedios de volumen total glandular en pacientes con hallazgos nodulares, llama la atención que entre los datos registrados existan pacientes con valores muy similares a lo reportado en la literatura como volúmenes normales en presencia de patología nodular tiroidea(AU)


The scientific community has been concerned with quantifying thyroid volume according to variables such as sex, age, and associated iodine deficiencies; however, despite the global use of TI-RADS to estimate the risk of malignancy in thyroid pathologies, there is not enough information in regarding whether or not the size of the gland is related to this scale. Objective: to compare the Thyroid Volume with TI-RADS in patients treated in the diagnostic ultrasound unit of the Naguanagua Clinical Center in the period January 2022 - January 2023. Methods: observational-descriptive study of a comparative level, with a crosssectional and prospective design. Non-probabilistic census sample, covering all the patients who underwent thyroid ultrasound in the established period. A record was made regarding the quantification of the volume of: right thyroid lobe, left thyroid lobe and total thyroid, TI-RADS, age and sex of the patient. The ANOVA statistic was used and the free license Statistical® program was used. Results: sample of 126 patients, mean age 51.71 ± 1.44 years, median 53 years. When the Total Thyroid Volume was compared with TI-RADS, it was found that the highest mean was registered by those patients classified as 4B (p <0.05). Conclusion: even when higher total glandular volume averages are recorded in patients with nodular findings, it is noteworthy that among the recorded data there are patients with values very similar to those reported in the literature as normal volumes in the presence of thyroid nodular pathology(AU)


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Doenças da Glândula Tireoide , Glândula Tireoide/anatomia & histologia , Diagnóstico por Imagem , Nódulo da Glândula Tireoide/diagnóstico por imagem
8.
Chinese Journal of Reparative and Reconstructive Surgery ; (12): 1471-1476, 2023.
Artigo em Chinês | WPRIM | ID: wpr-1009085

RESUMO

OBJECTIVE@#To investigate the early effectiveness of the Ti-Robot assisted femoral neck system (FNS) in the treatment of elderly Garden type Ⅱ and Ⅲ femoral neck fractures.@*METHODS@#A retrospective analysis was conducted on the clinical data of 41 elderly patients with Garden type Ⅱ and Ⅲ femoral neck fractures who were admitted between December 2019 and August 2022 and met the selection criteria. Among them, 21 cases were treated with Ti-Robot assisted FNS internal fixation (study group), and 20 cases were treated solely with FNS internal fixation (control group). There was no significant difference in baseline data, including gender, age, side, cause of injury, time from injury to surgery, fracture Garden classification, and fracture line classification, between the two groups ( P>0.05). Surgical effectiveness was evaluated based on parameters such as operation time (including incision time and total operation time), reduction level, number of dominant pin insertions, intraoperative fluoroscopy frequency, incision length, whether to extend the incision, need for assisted reduction, postoperative hospital stay, fracture healing time, incidence of osteonecrosis of the femoral head, postoperative visual analogue scale (VAS) score at 1 day, and Harris hip score at last follow-up.@*RESULTS@#The study group showed significantly shorter incision time, fewer dominant pin insertions, fewer instances of extended incisions, fewer intraoperative fluoroscopy frequency, and smaller incisions than the control group ( P<0.05). There was no significant difference in total operation time, reduction level, and assisted reduction frequency between the two groups ( P>0.05). Both groups achieved primary wound healing postoperatively, with no complications such as incision leakage or skin infection. All patients were followed up 12-24 months with an average of 14.6 months. Fractures healed in both groups, with no significant difference in healing time ( P>0.05). There was no significant difference in postoperative hospital stay between the two groups ( P>0.05). The study group showed significantly better VAS score at 1 day after operation and Harris hip score at last follow-up when compared to the control group ( P<0.05). No complication such as internal fixation failure, fracture displacement, or hip joint varus occurred in both groups during the follow-up. Osteonecrosis of the femoral head occurred in 1 patient of the control group, while no was observed in the study group, and the difference in the incidence of osteonecrosis of the femoral head between the two groups was not significant ( P=0.488).@*CONCLUSION@#Compared to sole FNS internal fixation treatment, Ti-Robot assisted FNS internal fixation for elderly Garden typeⅡ and Ⅲ femoral neck fractures can reduce incision time, achieve minimally invasive and accurate nail implantation, and decrease intraoperative fluoroscopy frequency, leading to improved postoperative hip joint function recovery.


Assuntos
Humanos , Idoso , Colo do Fêmur , Robótica , Estudos Retrospectivos , Resultado do Tratamento , Titânio , Fraturas do Colo Femoral/cirurgia , Fixação Interna de Fraturas , Osteonecrose , Ferida Cirúrgica
9.
Arq. bras. cardiol ; 119(6): 946-957, dez. 2022. tab, graf
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1420140

RESUMO

Resumo Fundamento: As matrizes metaloproteinases (MMPs) podem afetar o volume extracelular (VEC) e seus compartimentos, e isso pode oferecer informações mais detalhadas sobre o mecanismo de remodelação adversa (RA) do ventrículo esquerdo (VE) após o infarto agudo do miocárdio (IM). Objetivos: Investigar o papel que as alterações (Δ) nos compartimentos de VEC (volume matriz (MVi) e volume celular (CVi)) desempenham no desenvolvimento de RA após o IM, e sua relação com as expressões de MMP-2. Métodos: Um total de noventa e dois pacientes com primeiro IM passaram por exames de imagens por ressonância magnética cardiovascular 3 Tesla realizados 2 semanas (linha de base) e 6 meses após o IM. Medimos o mapeamento T1 com sequências MOLLI. O VEC foi obtido após o realce pelo gadolínio. O VEC e a massa do VE foram usados para calcular o MVi e o CVi. A RA foi definida como um aumento de ≥ 12% no volume diastólico final do VE em 6 meses. As MMPs foram medidas usando-se um sistema de imunoensaio multiplex em grânulos no primeiro dia (linha de base) e 2 semanas após o IM. Um P valor <0,05 foi aceito como estatisticamente significativo. Resultados: Os níveis de linha de base de MVi média e VEC médio foram mais altos no grupo com RA em comparação com o grupo sem RA (42,9±6,4 vs. 39,3±8,2 %, p= 0,037; 65,2±13,7 vs. 56,7±14,7 mL/m2, p=0,010; respectivamente). Os níveis de CVi eram semelhantes entre os grupos. Foi encontrada uma correlação positiva entre os níveis de linha de base de MMP-2 e os níveis de linha de base de VEC (r=0,535, p<0,001) e MVi (r=0,549, p<0,001). O aumento dos níveis de ΔMVi foi um preditor independente da RA (RC=1,03, p=0,010). O ΔMVi teve um desempenho diagnóstico superior quando comparado ao ΔVEC na previsão do (ΔAUC: 0,215±0,07, p<0,001). Conclusão: Níveis altos de MVi estão associados à RA, e o ΔMVi foi um preditor independente de RA. Isso pode estar associado à liberação de MMP-2 devido ao aumento da resposta inflamatória.


Abstract Background: Matrix metalloproteinases (MMPs) can affect myocardial extracellular volume (ECV) and its compartments, and this can provide more detailed information about the mechanism of adverse left ventricular (LV) remodeling (AR) after acute myocardial infarction (MI). Objectives: To investigate the role of changes (Δ) in ECV compartments (matrix volume (MVi) and cell volume (CVi)) in the development of AR after MI, and their relationship with MMP-2 expressions. Methods: Ninety-two first MI patients who underwent 3 Tesla cardiovascular magnetic resonance imaging performed 2 weeks (baseline) and 6 months post-MI. We measured T1 mapping with MOLLI sequences. ECV was performed post-gadolinium enhancement. ECV and LV mass were used to calculate MVi and CVi. AR was defined as an increase of ≥ 12% in LV end-diastolic volume in 6 months. MMPs were measured using a bead-based multiplex immunoassay system at first day (baseline) and 2 weeks post-MI. P <0.05 was accepted as statistically significant. Results: Mean ECV and mean MVi baseline levels were higher in AR group compared to without AR group (42.9±6.4 vs 39.3±8.2%, p= 0.037; 65.2±13.7 vs 56.7±14.7 mL/m2, p=0.010; respectively). CVi levels was similar between groups. A positive correlation was found between baseline levels of MMP-2 and baseline levels of ECV (r=0.535, p<0.001) and MVi (r=0.549, p<0.001). Increased ΔMVi levels was independently predictor of AR (OR=1.03, p=0.010). ΔMVi had superior diagnostic performance compared to ΔECV in predicting AR (ΔAUC: 0.215±0.07, p<0.001). Conclusion: High MVi levels are associated with AR, and ΔMVi was independently predictor of AR. This may be associated with MMP-2 release due to increased inflammatory response.

10.
Aletheia ; 54(1): 45-54, jan.-jun. 2021. ilus, tab
Artigo em Português | LILACS-Express | LILACS, INDEXPSI | ID: biblio-1285018

RESUMO

RESUMO As forças pessoais/de caráter são as características psicológicas positivas que se refletem nos pensamentos, sentimentos e comportamentos. Esse artigo objetivou descrever as forças pessoais/de caráter mais prevalentes em 60 profissionais de Tecnologia da Informação e comparar quatro grupos distintos nos cargos de Atendimento e Suporte Técnico, Desenvolvedor de Software, Gestor e Líder Técnico em um Parque Tecnológico do Sul do Brasil. Estudo com delineamento quantitativo, descritivo, comparativo e transversal com aplicação online de um Questionário Sócio Demográfico e Laboral e da Escala das Forças de Caráter. As forças mais prevalentes são a imparcialidade, a curiosidade, a bondade, o pensamento crítico e o amor ao aprendizado. As forças com menor prevalência são a apreciação do belo, a espiritualidade, o perdão, a inteligência social e a sensatez. As implicações práticas sugerem que as características psicológicas positivas sejam fortalecidas em processos de desenvolvimento pessoal e profissional dos trabalhadores de TI no âmbito organizacional.


ABSTRACT Character strengths are the positive psychological characteristics that are reflected in thoughts, feelings and behaviors. This article aimed to describe the most prevalent character strengths in 60 Information Technology (IT) professionals and compare four distinct groups in the positions of Service and Technical Support, Software Developer, Manager and Technical Leader in a Technology Park in the Southern Brazil. Study with quantitative, descriptive, comparative and cross-sectional design with online application of a Socio-Demographic and Labor Questionnaire and the Scale of Character Strengths. The most prevalent strengths are impartiality, curiosity, kindness, critical thinking and love of learning. The least prevalent character strengths are appreciation of beauty, spirituality, forgiveness, social intelligence and wisdom. Practical implications suggest that positive psychological characteristics should be strengthened in the personal and professional development of IT workers at organizations.

11.
West China Journal of Stomatology ; (6): 531-539, 2021.
Artigo em Inglês | WPRIM | ID: wpr-921370

RESUMO

OBJECTIVES@#This study was performed to fabricate a bionic coating with titanium (Ti) phosphate to promote the osseointegration of Ti substrate implants.@*METHODS@#Phosphorylated micro/nanocoating was prepared on the surface of pure titanium (i.e., TiP-Ti) by hydrothermal process under special pressure, and the untreated smooth pure titanium (cp-Ti) was selected as the control. To evaluate the characteristics of the coating surface, scanning electron microscopy, X-ray diffraction, atomic force microscopy, and contact-angle measurement were performed. In addition, the effects of TiP-Ti on the proliferation, adhesion, and differentiation of rat bone marrow mesenchymal stem cells (BMSCs) were investigated by using @*RESULTS@#The TiP-Ti surface presented a bionic structure with coexisting nanoscale 3D spatial structure and microscale pores. @*CONCLUSIONS@#A bionic structure with TiP-Ti micro/nanoscale coating was successfully fabricated, indicating a promising method for modifying the surface of implants.


Assuntos
Animais , Ratos , Implantes Dentários , Osseointegração , Osteogênese , Óxidos , Fosfatos , Propriedades de Superfície , Titânio
12.
Más Vita ; 2(4): 80-87, dic. 2020. tab
Artigo em Espanhol | LILACS, LIVECS | ID: biblio-1373018

RESUMO

La prevalencia del nódulo tiroideo (NT) en la población general es de entre el 2 al 7% por palpación y de 19 a 76% por ultrasonido. Su incidencia es más alta con la edad, en personas provenientes de áreas con deficiencia de yodo, en mujeres, y después de exposición a radiación. Objetivo: Estudiar distintas fuentes bibliográficas para así establecer la importancia del uso práctico de la clasificación TI-RADS en el nódulo tiroideo. Metodología: Se constituye en una investigación de carácter documental, tanto bibliográfica como digital. Resultados: La importancia del estudio del nódulo tiroideo radica en la necesidad de excluir cáncer, por lo cual, todo nódulo tiroideo >1cm debe ser evaluado. Los nódulos <1cm serán sospechosos cuando se encuentren asociados a factores de riesgo y en presencia de hallazgos ultrasonográficos sugestivos de malignidad. La clasificación TI-RADS de los NT basada en un sistema de puntuación acorde a los criterios ecográficos más relevantes de malignidad tiene una mejor y más fácil aplicación en la práctica diaria. Conclusión: Según los criterios de malignidad y la puntuación asignada en este estudio, la posibilidad de que un NT con un punto en la escala sea maligno es de aproximadamente un 10%, mientras que la probabilidad para aquellos con dos puntos es casi del 50% y para los valorados con tres o cuatro puntos del 85%. Todos los NT con 5 o más puntos son malignos. El presente artículo resume una comparación de referencias bibliográficas para actualización y aplicación de la clasificación TIRADS(AU)


The prevalence of the thyroid nodule (TN) in the general population is between 2 to 7% by palpation and from 19 to 76% by ultrasound. Its incidence is higher with age, in people from iodine-deficient areas, in women, and after exposure to radiation. Objective: To study different bibliographic sources in order to establish the importance of the practical use of the TI-RADS classification in the thyroid nodule. Methodology: It constitutes a documentary research, both bibliographic and digital. Results: The importance of studying the thyroid nodule lies in the need to exclude cancer, therefore, any thyroid nodule> 1cm should be evaluated. Nodules <1cm will be suspicious when associated with risk factors and in the presence of ultrasonographic findings suggestive of malignancy. The TI-RADS classification of NTs based on a scoring system according to the most relevant ultrasound criteria of malignancy has a better and easier application in daily practice. Conclusion: According to the malignancy criteria and the score assigned in this study, the possibility that a TN with one point on the scale is malignant is approximately 10%, while the probability for those with two points is almost 50% and for those valued with three or four points of 85%. All TNs with 5 or more points are malignant. This article summarizes a comparison of bibliographic references for updating and applying the TIRADS classification(AU)


Assuntos
Humanos , Deficiência de Iodo , Nódulo da Glândula Tireoide , Metodologia como Assunto , Palpação , Radiação , Diagnóstico por Imagem , Fatores de Risco
13.
Rev. Fac. Med. UNAM ; 63(1): 14-19, ene.-feb. 2020. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1155381

RESUMO

Resumen: Introducción: La incidencia de cáncer papilar de tiroides (PTC) ha aumentado de 1975 a 2015. Basados en criterios publicados, el ultrasonido (US) es muy efectivo para predecir el riesgo de malignidad. Todos estos criterios se enfocan en los nódulos tiroideos; sin embargo, 2% de los casos se pueden presentar como focos ecogénicos difusos sin un nódulo identificable. Caso: Mujer de 17 años con historia de 3 meses con una masa palpable en la región anterior derecha del cuello, sin otros síntomas. El US de cuello revela múltiples focos ecogénicos de distribución difusa en el parénquima tiroideo con un nódulo de 6 mm TI-RADS 5 en el lóbulo izquierdo y ganglio linfáticos con componentes sólidos y quísticos, pérdida del hilio graso y con puntos ecogénicos. Se le realizó tiroidectomía total con linfadenectomía bilateral. Discusión: Las microcalcificaciones son muy sugestivas de CPT. Los ecos puntiformes se correlacionan en patología con una forma de calcificación distrófica llamada cuerpos de Psammoma, los cuales se depositan en tejido no viable. La tiroiditis crónica también puede presentar calcificaciones distróficas. Por lo tanto, un parénquima tiroideo normal con presencia de microcalcificaciones, obliga a realizar una biopsia con aguja fina para descartar CPT. Estudios recientes sugieren que la lobectomía es una opción viable y debe ser la primera elección en CPT localizado (< 2 cm). Sin embargo, esto no se debe realizar en estos pacientes, ya que la presencia de microcalcificaciones difusas nos indica un tamaño del tumor mucho mayor y resultaría en un pronóstico desfavorable. Conclusión: Las microcalcificaciones difusas deben obligar al radiólogo a sospechar la variedad difusa del CPT como primera sospecha diagnóstica.


Abstract: Introduction: The incidence of thyroid papillary cancer (PTC) has increased from 1975 to 2015. Ultrasound is effective for predicting thyroid malignancy based on published criteria. All of these criteria focus on thyroid nodules but also 2% of the cases may appear as diffuse punctuate echogenic foci without an identifiable nodule. Case: A 17-year-old female with a 3-month history of a palpable mass on the right anterior side of the neck without any further symptoms. Neck ultrasound revealed multiple punctuate echogenic foci scattered along the thyroid parenchyma with a 6 mm nodule TI-RADS 5 on the left lobe, lymph nodes with cystic and solid components, loss of echogenic hilum and punctuate echogenic foci. The patient underwent a total thyroidectomy with bilateral lymphadenectomy. The pathology report revealed diffuse distribution of papillary cancer with a nodule on the left lobe and metastatic disease on the lymph nodes. Discussion: Microcalcifications are highly suggestive of PTC. Punctuate echogenic foci correlate in pathology with a form of dystrophic calcifications, called Psammoma bodies, which are deposited in nonviable tissue. Chronic thyroiditis may also present dystrophic calcifications. Thus, a normal thyroid parenchyma with microcalcifications should encourage the radiologist to perform a fine-needle aspiration biopsy (FNAB). Recent studies suggest that lobectomy is a viable option and should be pursued in the setting of localized PTC (<2 cm). A lobectomy should not be performed in patients with diffuse microcalcifications since it would result in an unfavorable outcome. Conclusions: Diffuse microcalcifications should immediately make the radiologist suspect diffuse PTC as a first diagnostic option.

14.
Chinese Journal of Medical Instrumentation ; (6): 205-209, 2020.
Artigo em Chinês | WPRIM | ID: wpr-942728

RESUMO

Aiming at the medical practice problems of the surgical steel medical instruments, such as the crevice corrosion, the poor mechanical compatibility and the Ni, Cr plasma exudation, the laser deposition of Ti-6Al-4V alloy cladding layer at the local functional area as alternative coating was proposed and realized as a new process method. The accurate element content and good formability Ti-6Al-4V cladding powder was chosen, the low power and high duty cycle optimized laser process was adopt, the alternative coating of good fusion and low dilution was prepared. Through the elemental line scanning, the interface microstructure analysis and the experiments of basic mechanical properties, the basic properties of the cladding were characterized and verified. The experiments results showed that, the Ti, Al and V contents of the top coating were respectively about 88%, 4.9% and 3.9%, no sensitizing ions such as Cr and Ni were detected. Initial equiaxed α phase, flake β phase dist were distributed in the coating and interface, the α' martensite was precipitated at the boundary of the flake β phase, some refined granular β phase dispersion pinned to the grain boundary of basket structure. The microhardness of cladding layer was 352.08~312.76 HV0.1. The friction coefficient of the cladding layer was about 0.22~0.65. A new technology and method reference for improving and upgrading the performance of surgical medical devices is provided by this research.


Assuntos
Ligas , Corrosão , Teste de Materiais , Aço , Titânio
15.
Journal de la Faculté de Médecine d'Oran ; 4(2): 579-586, 2020. figures, tables
Artigo em Francês | AIM | ID: biblio-1415538

RESUMO

Introduction: Objectif-Dans les dernières décennies il y a eu un intérêt croissant pour l'étude des plantes médicinales et leur utilisation traditionnelle pour le traitement de diverses maladies. L'olivier ou Olea europaea L. constitue une entité indissociable des peuples méditerranéens. Cette plante appartient à la grande famille des oleaceae. L'objectif de cette étude a été d'évaluer l'activité anti-oxydante des extraits éthanoliques de quatre variétés sauvages de la plante O.europaea des régions de l'Est algérien : Batna et Mila (hautes-plateaux), Biskra (Sahara) et Skikda (ville côtière). Matériels et méthodes - L'évaluation de l'activité anti-oxydante in vitro des extraits éthanoliques de la plante O.europaea a été réalisée par différentes méthodes, notamment le piégeage du radical libre DPPH• et le pouvoir réducteur des ions ferriques. Résultats : L'analyse quantitative des extraits éthanoliques des feuilles de la plante O.europaea a révélé que l'extrait de Mila était plus riche (420.36 mg GAE/g MS), suivi de celui de Batna (396.84 mg GAE/g MS), puis celui de Biskra (de 380.69 mg GAE/g MS) et enfin de l'extrait de Skikda (368.45 mg GAE/g MS). Les résultats de l'activité antiradicalaire des extraits éthanoliques ont montré que ceux de Batna et Mila possédaient le pouvoir le plus important. Conclusion -Les résultats obtenus confirment favorablement l'utilisation des feuilles d'O.europaea en médecine traditionnelle algérienne pour le traitement de diverses maladies.


Introduction-Objective-In recent decades the study of medicinal proprieties of Olea europaea showed an increase interest of medicinal plants and their traditional use for the treatment of various diseases. The olive tree or Olea europaea L. is an inseparable entity of the Mediterranean people. This plant belongs to the large family of oleaceae. The purpose of this study was to assess the antioxidant activity of the ethanolic extracts from four wild varieties of O.europea in the eastern regions of Algeria: Batna and Mila (highlands), Biskra (Sahara) and Skikda (coastal city). Material and methods - The evaluation of the antioxidant activity in vitro of the ethanolic extracts of O.europaea plant was carried out by various methods, in particular, 1,1-diphenyl-2-picryl-hydrazyl (DPPH) free radical scavenging effect and ferric reducing antioxidant power (FRAP). Results -Quantitative analysis of ethanolic extracts from the leaves of the plant O.europaea revealed that Mila's extract was richer (420.36 mg GAE / g DM), followed by that of Batna (396.84 mg GAE / g DM), then that of Biskra (380.69 mg GAE / g MS) and finally by Skikda extract (368.45 mg GAE / g MS). The results of DPPH free radical scavenging of the ethanolic extracts showed that those of Batna and Mila had the most important power. Conclusion - The obtained results favorably confirm the use of O.europaea leaves in traditional Algerian medicine for the treatment of various diseases.


Assuntos
Humanos , Terapêutica , Extratos Vegetais , Olea , Etanol , Antioxidantes , Plantas Medicinais , Oleaceae
16.
Journal of Shanghai Jiaotong University(Medical Science) ; (12): 76-80, 2020.
Artigo em Chinês | WPRIM | ID: wpr-843266

RESUMO

Objective:To evaluate the diagnostic value of ultrasound thyroid imaging-reporting and data system (TI-RADS) combined with three-dimensional shear wave elastography (3D-SWE) technique in thyroid microcarcinoma. Methods:From Jun. 2017 to Jan. 2018, 66 patients with 67 thyroid nodules in the Department of Ultrasound of Renji Hospital, Shanghai Jiao Tong University School of Medicine were recruited. All thyroid nodules were classified as TI-RADS 4-5, and the maximum diameter was 5.0-10.0 mm. After routine ultrasound examination, all thyroid nodules were evaluated by TI-RADS classification, 3D-SWE technique, fine-needle aspiration biopsy (FNAB) examination and an additional BRAFV600E gene mutation test. All the nodules were divided into benign group and malignant group according to the results of surgical pathology or fine-needle aspiration combined with BRAFV600E gene detection. The threshold value of the parameters in 3D-SWE for differentiating benign and malignant thyroid nodules was calculated, and the TI-RADS was further adjusted by Young's modulus parameters of the lesion to obtain combined TI-RADS (conventional ultrasound combined with 3D-SWE) for detecting the benign and malignant nodules. Results:Among the 67 thyroid nodules, 38 of them were malignant and 29 were benign. The optimal cut-off point of three-dimensional maximum Young's modulus in sagittal plane (3D-S-Emax) was 24.6 kPa. The area under the curve (AUC) value, sensitivity, specificity and accuracy of 3D-S-Emax were 0.683, 65.8%, 65.5% and 65.7%, respectively. The AUC value for combined TI-RADS was 0.801 and that for conventional TI-RADS was 0.794, without statistical difference. The sensitivity, specificity and accuracy of conventional TI-RADS and combined TI-RADS were 63.2%, 82.8%, 71.6%, and 86.8%, 69.0%, 79.1%, respectively. Only sensitivity of combined TI-RADS was significantly higher than that of conventional TI-RADS (P=0.004). Conclusion:Combined TI-RADS and conventional TI-RADS have similar diagnostic value in thyroid microcarcinoma, while combined TI-RADS has higher diagnostic sensitivity and lower missed diagnosis rate.

17.
Journal of Shanghai Jiaotong University(Medical Science) ; (12): 671-673, 2020.
Artigo em Chinês | WPRIM | ID: wpr-843201

RESUMO

Elastic imaging is a technique for converting the elastic modulus of soft tissues to real-time computer images. As one of the branches of elastic imaging, tactile imaging is distinguished by the feature of pressing directly against the surface of soft tissues. It is a mature option to diagnose diseases in urology, general surgery, gynecology and obstetrics. In recent years, tactile imaging, especially vaginal tactile imaging, has been used to evaluate female pelvic floor dysfunction diseases. This review is about tactile imaging and its application to the field of pelvic floor dysfunction.

18.
Interdisciplinaria ; 36(2): 203-215, dic. 2019. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1056548

RESUMO

Resumen En la investigación cualitativa, el análisis y la interpretación de los datos es una tarea de difícil manejo, incluso para los investigadores más experimentados. Si bien existen muchas técnicas disponibles para llevar a cabo el análisis de datos cualitativos, algunos autores relevantes del área proponen que es posible identificar un núcleo básico sin necesidad de hacer coincidir las distintas perspectivas del método cualitativo. Hacer foco en esta comunalidad permitirá hacer más comprensible la tarea de análisis para los investigadores noveles. El objetivo principal del presente trabajo es mostrar en qué consiste este núcleo básico de análisis, dando cuenta de los pasos necesarios para llevarlo a cabo. Además, se revisan técnicas concretas para la detección de temas, se presentan ejemplos haciendo uso del software Atlas.ti, y se muestran las formas posibles de presentación de los resultados.


Abstract Within the research process, the analysis of the data emerges as one of the most important steps. In qualitative research, the analysis of data is a difficult task for even the most experienced researchers and often brings up many doubts about the way to implement it. It is therefore necessary to have material that facilitates the analysis process. Even though there are numerous manuals that focus on the analysis of qualitative data, researchers often can be confused with the large number of names that this type of analysis receives (e.g. Thematic Analysis, Content Analysis) or with the various qualitative methods (e.g. Phenomenology, Grounded Theory) that are available. Each of these qualitative approaches presents a particular language to detail the research process, which makes it difficult to recognize common aspects shared by these methods. Recently, the American Psychological Association has emphasized the need to identify, within the various qualitative methods and procedures, shared standards for reporting this type of work. In agreement with the above, several qualitative researchers have pointed out that beyond the aforementioned diversity it is possible to identify a basic core with regard to qualitative analysis, without having to match the different perspectives of the qualitative method, such as Grounded Theory, Ethnography ore Phenomenology. Focusing on this communality will facilitate a simpler and clearer approach to the data analysis process. The analysis process mainly involves 1) data condensation, and 2) presentation of results. Following this line, the present manuscript aims to: (a) develop what the basic core of data analysis consists of, (b) show the necessary steps to carry out this analysis process, (c) review specific techniques for the detection of categories, (d) present examples using the Atlas.ti software, and (e) show the possible ways of presenting the results. Researchers have realized the importance of having methodological works that facilitate the analysis of qualitative data, and allow answering the question: What does qualitative analysis look like in practice?. The development of this type of work pretends on the one hand to facilitate the understanding of the process of qualitative data analysis and, on the other hand, serve to shape better and in a more standard way which was the data analysis procedure applied in the respective investigations. This material should be taken as a first step in the understanding of the process, and it should not be understood that the qualitative analysis is reduced only to what is developed in this article. For example, in the first level grouping step or first coding cycle, the researcher can make use of 25 different types or forms of coding (e.g., live coding). Even so, the development of works such as the present manuscript is intended to facilitate the understanding and reporting the process of qualitative data analysis. Beyond the name with which the researcher calls the analysis procedure carried out, it is relevant to report in his works the basic steps (i.e. Identification, First and Second Level of Categorization), and the specific techniques used to detect categories or topics (e.g. repetition or similarities). Likewise, it is advisable to follow the guidelines recently published by the APA for the publication of qualitative research. We hope that this material will be useful especially for new researchers who need an introductory text to carry out the qualitative data analysis.

19.
Artigo | IMSEAR | ID: sea-213954

RESUMO

This research article gives an overview of the extensive research of Ti-6Al-4V from past few decades helped in studying about the features, properties, characteristics and application of aerospace industries. The final objective of study is to obtain the inherent advantages of Ti-6Al-4V like low elasticity modulus, high strength, low density and more resistant to fatigue and corrosion that leads to rely on the required knowledge for the employment of application which improves all physical and mechanical properties.

20.
Journal of Prevention and Treatment for Stomatological Diseases ; (12): 17-22, 2019.
Artigo em Chinês | WPRIM | ID: wpr-751050

RESUMO

Objective@#To investigate the physical properties of Ti-6Al-4V clasps generated by selective laser melting (SLM) with different construction directions and to compare these clasps with cast clasps, which could provide a basis for fabricating SLM clasps with high precision and excellent mechanical properties. @*Methods@# Ti-6Al-4V clasps were fabricated by SLM at 0 degrees (SLM0 group), 45 degrees (SLM45 group) and 90 degrees (SLM90 group) (n = 12). Twelve clasps were cast by the casting method as the control group. Meanwhile, four metal abutments were cast randomly as the abutments of the four groups. X-ray was used to detect cracks in the clasps of each group. The roughness of the clasps was measured by confocal microscopy, the fitness tests between clasps and abutment were processed by stereomicroscopy, and the microstructure of clasps in each group was observed under a metallographic microscope to evaluate the physical properties.@*Results @# There were 0-8 visible cracks in the casting group but no obvious defects in the SLM groups. The maximum surface roughness was observed in the cast group (18.102 ± 3.762) μm, while the minimum roughness was observed in the SLM90 group (5.942 ± 1.486) μm (P < 0.05). There was no statistically significant difference in surface roughness between the SLM0 group [(8.711 ± 2.378) μm] and the SLM45 group [(8.513 ± 1.161) μm]. Fitness was worst in the casting group [(68.445 ± 14.876) μm] and best in the SLM90 group [(33.417 ± 5.880) μm] (P < 0.05). There was no statistically significant difference in fitness between the SLM0 group [(52.917 ± 12.102) μm] and the SLM45 group [(50.889 ± 7.011) μm]. In addition, the growth direction of the β grains was roughly parallel to the build direction, and acicular α grains were present between β grains. SLM was composed of fine grains, while the cast group had large grains.@* Conclusions@# Specimens generated by SLM had finer grains than cast specimens. In addition, SLM90 clasps had the highest fitness and the lowest surface roughness.

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