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1.
Sci Total Environ ; 904: 166750, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37659537

RESUMO

This study presents a novel method for producing acicular aragonite using argon oxygen decarburization (AOD) slag while controlling the reaction temperature, reaction time, stirring speed, and the magnesium-to­calcium stoichiometric ratio. This approach provides steel plants with an opportunity to decrease their CO2 emissions and promote efficient resource utilization and CO2 storage through the production of high-quality value-added products. The experimental results showed that reaction temperature was the most significant factor affecting the carbonation efficiency of AOD slag, followed by reaction time, stirring speed, CO2 partial pressure, and the liquid-to-solid ratio (L/S). The study also found that elevated temperature and prolonged reaction duration favored the preferential precipitation of aragonite. Additionally, raising the temperature and the magnesium-to­calcium stoichiometric ratio was shown to enhance the formation of aragonite, affecting its crystal growth orientation and dimensions. The optimal combination of reaction parameters for the preparation of acicular aragonite was found to be the reaction time of 8 h, the magnesium-to­calcium stoichiometric ratio of 0.8, the reaction temperature of 120 °C, and the stirring speed of 200 r·min-1. Under these conditions, the resulting acicular aragonite exhibited excellent overall uniformity, a large aspect ratio, and a smooth crystal surface, with a content of 91.49 %, a single crystal length ranging from 9.86 to 32.6 µm, and a diameter ranging from 0.63 to 2.15 µm. This study provides valuable insights into the efficient production of acicular aragonite from steel slag while reducing CO2 emissions and promoting the sustainable use of resources.

2.
Orthop Surg ; 12(4): 1182-1189, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32618427

RESUMO

OBJECTIVE: To assess whether the computed tomography (CT)-based method of three-dimensional (3D) analysis (Mimics) was accurate and reliable for spine surgical anatomical measurements. METHODS: A total of 40 lumbar segments and 32 inter-vertebral discs from eigth adult male cadavers without fractures or deformities fixed with the classical formaldehyde method were included in this research on 5 June 2017. CT scans including seven dimensions: anterior height of the vertebral body (VBHa), middle height of the vertebral body (VBHm), posterior height of the vertebral body (VBHp), width of the upper endplate (EPWu), depth of the upper endplate (EPDu), anterior height of the inter-vertebral disc in the median sagittal plane (IDHa), and posterior height of the inter-vertebral disc in the median sagittal plane (IDHp). They were performed based on uniform conditions (slice thickness: 0.625 mm) using a CT scanner on 8 June 2017. Afterwards, the surgical anatomical measurements were conducted with a Vernier caliper on 12 June 2017. The computer-aided anatomical measurements were conducted by three investigators using Mimics 16.0 to perform 3D reconstructions of CT bone on 16 June 2017. Finally, the length and angle were measured with associated measurement tools, yielding a verified accuracy of 0.01 mm and 0.01°, respectively. Each measurement was repeated three times, and all anatomical data was analyzed using the statistical software and P-value < 0.05 was considered statistically significant. RESULTS: The results showed no statistically significant difference was observed between the surgical anatomical and computer-aided anatomical measurements (P > 0.05) for lumbar vertebra measurements, and the absolute difference between surgical and computer-aided data were all less than 1.0 mm (for the VBHa, VBHm, VBHp, EPWu, and EPDu were 0.12, 0.03, 0.03, 0.31, and 0.03 mm, respectively). Moreover, although the absolute differences of discs was larger than those of lumbar vertebras, no significant differences were detected between the computer-aided and surgical anatomical measurements for the IDHa, as well as IDHp in the vast majority of measurements (P = 0.543, 0.079 or 0.052 for IDHa, and P = 0.212, 0.133 or 0.042 for IDHp). In addition, excellent reliability correlation was observed between the measurements of each investigator, and the reliability coefficients in the intra-groups were all greater than 0.9 except for IDHp (reliability coefficient = 0.892). Additionally, the reliability coefficients were greater than 0.9 for the all between-group correlations, and a significant correlation was also observed. Furthermore, no statistically significant difference for three anatomical values was found in the computer-assisted measurements of the lumbar bone structure (P > 0.05). Similarly, we did not observe a statistical difference in the anatomical data of the lumbar discs from the three measures (P > 0.05). CONCLUSIONS: Computer-aided anatomical measurement for spine based on CT scans presents the high accuracy and reliability for improving spinal surgical procedures.


Assuntos
Imageamento Tridimensional , Disco Intervertebral/diagnóstico por imagem , Vértebras Lombares/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Corpo Vertebral/diagnóstico por imagem , Adulto , Cadáver , Humanos , Disco Intervertebral/anatomia & histologia , Vértebras Lombares/anatomia & histologia , Masculino , Reprodutibilidade dos Testes , Corpo Vertebral/anatomia & histologia
3.
Zhongguo Zhong Yao Za Zhi ; 44(16): 3368-3373, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31602897

RESUMO

Tripterygium wilfordii preparations,with various biological activities such as immunosuppressive,anti-inflammatory and anti-cancer effects,are widely used in the treatment of autoimmune diseases such as rheumatoid arthritis,lupus erythematosus,and nephrotic syndrome. They have definite therapeutic effect,but often cause serious adverse reactions and result in damages to liver,kidney,blood,reproduction,and other systems due to their complex compositions,great toxicity,and narrow margin between the toxic and therapeutic dosages. At present,T. wilfordii preparations produced by different manufacturers exhibit large variations in clinical efficacy and side effects in account of their different chemical compositions and quality fluctuation due to differences in raw materials and production process. However,the existing quality standards are controversial in terms of index components and content limit,which cannot be effectively used for the overall quality control of the preparations. In this paper,the research progress on chemical constituents,quality standard and quality control methods of four T. wilfordii preparations including Tripterygium Tablets,Tripterygium Zongtie Tablets,Tripterygium Shuangceng Tablets and Tripterygium Glycosides Tablets was reviewed,in order to provide ideas and reference for the quality improvement of this type of preparations.


Assuntos
Medicamentos de Ervas Chinesas/normas , Controle de Qualidade , Tripterygium/química , Comprimidos
4.
Zhong Yao Cai ; 36(6): 999-1002, 2013 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-24380289

RESUMO

OBJECTIVE: To optimize the freeze-dried powder preparation technology of recombinate hirudin-2 (rHV2) nanoparticle which has bio-adhesive characteristic for nasal delivery, also to investigate its stability and permeability through nasal membrane in vitro. METHODS: Taking the appearance, rediffusion of nanoparticle and rHV2 encapsulation efficiency as the evaluation indexes. Cryoprotector, the preparative technique and the effect of illumination and high temperature factors on its stability for rHV2 freeze-dried powder were investigated. Using Fraze diffusion cell technique, the permeability of rHV2 across rabbit nasal mucous membrane in chitosan solution, chitosan nanoparticle, and nanoparticle frozen-dried powder were compared with that in normal saline solution. RESULTS: The optimized preparation of rHV2 nanoparticle freeze-dried powder was as follows: 5% trehalose and glucose (1:1) was used as cryoprotector, nanoparticle solution was freezed for 24 h in vacuum frozen-dryer after being pre-freezed for 24 h. The content of rHV2 in the freeze-dried powder was 1.1 ug/mg. Illumination had little effect on the appearance, rediffusion and encapsulation efficiency of the rHV2 freeze-dried powder. High temperature could obviously influence the appearance of nanoparticle freeze-dried powder. The permeability coefficient (P) of nanoparticle was 5 times more than that in chictonson solution. It was indicated that chitosan nanoparticle has effect on increasing the permeability of rHV2. CONCLUSION: The freeze-dried powder of chitosan nanoparticle can be a good nasal preparation of rHV2.


Assuntos
Hirudinas/administração & dosagem , Hirudinas/farmacocinética , Mucosa Nasal/metabolismo , Tecnologia Farmacêutica/métodos , Absorção , Administração Intranasal , Animais , Quitosana/administração & dosagem , Quitosana/química , Sistemas de Liberação de Medicamentos , Estabilidade de Medicamentos , Liofilização , Glucose/administração & dosagem , Glucose/química , Masculino , Manitol/administração & dosagem , Manitol/química , Nanopartículas , Permeabilidade , Pós , Coelhos , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacocinética
5.
Zhongguo Yi Liao Qi Xie Za Zhi ; 33(4): 235-8, 2009 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-19938516

RESUMO

In the study the changes of scalp potential and cardiac autonomic nervous system during volitional control of heart beat are explored with the wavelet packet parameters and approximate entropy (ApEn) of Electroencephalogram (EEG) and heart rate variability. The results show that volition can control heart beat and the changes of brain activity are earlier than that of autonomic activity. But its control of heart beat is very different from the motor nervous system because different cortical positions are respectively concerned during the quick and slow control of heart beat. The pre-central areas of brain are correlated with parasympathetic activity by which HR is controlled to slow down. The post-central areas of brain are correlated with sympathetic activity by which HR is controlled to accelerate.


Assuntos
Sistema Nervoso Autônomo/fisiologia , Estado de Consciência/fisiologia , Frequência Cardíaca/fisiologia , Eletroencefalografia , Humanos , Couro Cabeludo
6.
World J Gastroenterol ; 15(35): 4410-4, 2009 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-19764092

RESUMO

AIM: To investigate the effect of paeonol on controlling the proliferation of colorectal cancer cell line HT-29 and to discuss its possible mechanism. METHODS: The inhibitory effect of paeonol on proliferation of HT-29 cells was detected by MTT assay. The results of apoptosis were measured by flow cytometry. Immunocytochemical staining was performed to detect the expression of cyclooxygenase-2 (COX-2) and protein p27 in HT-29 cells treated with paeonol at different concentrations. Reverse transcription-polymerase chain reaction (RT-PCR) was used for mRNA analysis. RESULTS: From the data of both MTT and flow cytometry, we observed that cell proliferation was inhibited by different concentrations of paeonol. By immunocytochemical staining, we found that HT-29 cells treated with paeonol (0.024-1.504 mmol/L) reflected reduced expression of COX-2 and increased expression of p27 in a dose-dependent manner. RT-PCR showed that paeonol down-regulated COX-2 and up-regulated p27 in a dose- and time-dependent manner in HT-29 cells. CONCLUSION: One of the apoptotic mechanisms of paeonol is down-regulation of COX-2. p27 is up-regulated simultaneously and plays an important part in controlling cell proliferation and is a crucial factor in the Fas/FasL apoptosis pathway.


Assuntos
Acetofenonas/farmacologia , Apoptose/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Ciclo-Oxigenase 2/metabolismo , Proliferação de Células/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p27/efeitos dos fármacos , Ciclo-Oxigenase 2/efeitos dos fármacos , Relação Dose-Resposta a Droga , Citometria de Fluxo , Células HT29/efeitos dos fármacos , Células HT29/metabolismo , Humanos , Imuno-Histoquímica , Antígeno Nuclear de Célula em Proliferação , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo , Regulação para Cima
7.
Zhongguo Zhong Yao Za Zhi ; 30(6): 422-6, 2005 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-15810444

RESUMO

OBJECTIVE: To characterize the different varieties of Pseudostellaria heterophylla during cultivation. METHOD: Using systematic selection in the main productive areas, the techniques of random design, all varieties were observed for 3 years. RESULT: The biological and 425 productive characteristics of P. heterophylla var. macrophylla, P. heterophylla var. Foliolum, and P. heterophylla var. anvense were significantly different (P < 0.01). There were also differences in ecological adaptability, plant characteristics, pollen granule, chromosomes, and isoenzyme of the three cultivars. CONCLUSION: The strain types of P. heterophylla was denominated for the first time. The characteristics and productivity index system of P. heterophylla varieties were determined.


Assuntos
Caryophyllaceae/anatomia & histologia , Cromossomos de Plantas , Lipase/análise , Plantas Medicinais/anatomia & histologia , Caryophyllaceae/enzimologia , Caryophyllaceae/genética , Catecol Oxidase/análise , Ecossistema , Flores/anatomia & histologia , Peroxidase/análise , Folhas de Planta/anatomia & histologia , Raízes de Plantas/anatomia & histologia , Plantas Medicinais/enzimologia , Plantas Medicinais/genética
8.
Zhongguo Yi Liao Qi Xie Za Zhi ; 26(6): 430-1, 444, 2002 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-16104323

RESUMO

Through the detection of the change of shear stress in blood, four coagulation parameters (t(r), delta tau/delta t, tau(max), S) can be automatically determined. The instrument can be used to automatically detect the process of blood coagulation and print coagulation curves. There is a great difference between different samples while there is a good repeatability with the same sample.


Assuntos
Testes de Coagulação Sanguínea/instrumentação , Testes de Coagulação Sanguínea/métodos , Modelos Teóricos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Design de Software , Fatores de Tempo
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