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1.
Micromachines (Basel) ; 15(6)2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38930776

RESUMO

Phase change materials (PCMs) are used to cool high-power-density electronic devices because of their high latent heat and chemical stability. However, their low thermal conductivity limits the application of PCMs. To solve this problem, a double-porosity porous aluminum skeleton/paraffin phase change materials (DPAS/PCM) was prepared via additive manufacturing and the water-bath method. The thermal performance of the DPAS/PCM heat sink (HS) was experimentally investigated to examine the effects of the positive- and reverse-gradient porosity structures of the DPAS/PCM. The results show that a positive-gradient porosity arrangement is more conducive to achieving a low-temperature cooling target for LED operation. In particular, the temperature control time for the positive gradient porosity structure increased by 4.6-13.7% compared with the reverse gradient porosity structure. Additionally, the thermal performances of uniform porous aluminum skeleton/paraffin (UAS) and DPAS/PCMs were investigated. The temperature control effect of the DPAS/PCM was better than that of the UAS/PCM HS at high critical temperatures. Compared with the UAS/PCM HS, the temperature control time of the DPAS/PCM HS is increased by 7.8-12.5%. The results of this work show that the prepared DPAS/PCM is a high-potential hybrid system for thermal management of high-power electronic devices.

2.
BJOG ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38747094

RESUMO

BACKGROUND: The associations between hysterectomy and cardiovascular disease (CVD) and mortality remains unlcear and a meta-analysis with cohort studies is lacking. OBJECTIVES: This study aimed to conduct a systematic review and meta-analysis of cohort studies to investigate the relationship between hysterectomy and CVD, coronary heart disease (CHD), stroke, heart failure, and all-cause, cardiovascular and cancer mortality. We further explored the effect of oophorectomy on the association between hysterectomy and these health outcomes. SEARCH STRATEGY: PubMed, EMBASE and Web of Science were searched up to 24 July 2023. SELECTION CRITERIA: Cohort studies. DATA COLLECTION AND ANALYSIS: Hazard ratios (HRs) and 95% confidence intervals (95% CIs) were pooled using a random-effects model. We used I2 to assess the heterogeneity between studies. MAIN RESULTS: Forty-three studies were included in the meta-analysis. Hysterectomy was significantly associated with an increased risk of CVD (pooled HR 1.11, 95% CI 1.09-1.13; n = 6; I2 = 0) and stroke (HR 1.09, 95% CI 1.04-1.14; n = 7; I2 = 52%), but with a decreased risk of cancer mortality (HR 0.93, 95% CI 0.86-1.00; n = 4; I2 = 81%). No significant association was observed between hysterectomy and CHD (n = 10; I2 = 83%), all-cause mortality (n = 8; I2 = 81%) or cardiovascular mortality (n = 7; I2 = 89%). Hysterectomy with and without oophorectomy was significantly associated with CVD and stroke risk, but showed a larger effect size for hysterectomy with oophorectomy. A significantly increased risk of CHD was observed in the subgroup of hysterectomy with oophorectomy, but not for the subgroup of hysterectomy alone. CONCLUSIONS: Hysterectomy may increase the risk of CVD, CHD and stroke, but not all-cause, cardiovascular or cancer mortality. Hysterectomy with oophorectomy may have a higher risk of CVD, CHD and stroke than hysterectomy alone. However, the results on CHD and mortality related to hysterectomy should be interpreted cautiously because of the high level of heterogeneity and unstable subgroup analyses.

3.
Micromachines (Basel) ; 15(4)2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38675324

RESUMO

To satisfy the demand for efficient heat transfer, a novel three-dimensional overall jagged internal finned tube (3D-OJIFT) was fabricated, using the rolling-ploughing/extruding method. The thermal performance of the 3D-OJIFT were studied and compared in experiments and three-dimensional numerical simulations. The RNG k-ε turbulence model is well verified with the experimental results. By analyzing the distributions of velocity, temperature, and turbulence kinetic energy, it was found that the 3D-OJIFT destroyed the development of the velocity and thermal boundary layers, increased the turbulence disturbance, and reduced the temperature gradient, thus improving the heat transfer. The influences of the jagged height and jagged spiral angle of the 3D-OJIFT are discussed. The Nu and f increased as the jagged height of the 3D-OJIFT increased. The Nusselt number of the 3D-OJIFT was 1.67-2.04 times the value for the smooth tube. In addition, the comprehensive heat transfer performance of the 3D-OJIFT improved after increasing the jagged spiral angle. Compared with conventional internal helical-finned tubes and other reinforcement structures reported in the literature, the 3D-OJIFT demonstrated better comprehensive heat transfer performance. Finally, empirical correlations of the 3D-OJIFT were obtained.

4.
Discov Oncol ; 14(1): 149, 2023 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-37597098

RESUMO

Ovarian cancer is a leading cause of death in females with gynecologic cancers. Pyroptosis is a relatively new discovered programmed cell death that is believed to be associated with inflammation. However, studies on pyroptosis-related lncRNAs in ovarian cancer are limited. In this study, we identified 29 pyroptosis-related genes and screened out 72 pyroptosis-related lncRNAs. Furthermore, the 72 lncRNAs were eliminated to 2 survival-related lncRNAs using Cox regression and Lasso regression to build an ovarian cancer prognostic prediction signature and were further validated on the test set. We adopted a riskscore from the two-gene signature, and the survival in low-risk group was higher than the high-risk group. Functional enrichment analysis indicated that the differentially expressed genes (DEGs) between two risk groups were associated with tumor immunity. This study implies that pyroptosis-related genes are closely related to tumor immunity and could be potential therapeutic factors for ovarian cancer treatment.

5.
Medicine (Baltimore) ; 102(11): e33201, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36930084

RESUMO

BACKGROUND: Low density lipoprotein receptor-related protein 11 (LRP11) was involved in the progression of several tumors. However, its role in cervical cancer still remains uncertain. METHODS: The original tumor data was downloaded from the Cancer Genome Atlas and genotype-tissue expression databases. The expression of LRP11 in normal tissues, tumor tissues and adjacent tissues were evaluated. In addition, we also explored the genetic alteration, prognostic value, and gene function of LRP11. We deeply assessed the interaction between LRP11 and tumor immunity at the pan-cancer level. Finally, research on the association between LRP11 and the resistance of anti-tumor drugs was carried out. RESULTS: LRP11 was highly expressed and played a risk prognostic factor in cervical cancer and a variety of tumors. Enrichment analysis revealed that LRP11 was involved in multiple tumor malignant pathways. Our research also pointed out the unique role between LRP11 and tumor immune microenvironment. The tumor immune microenvironment of patients with high expression of LRP11 are lack of most immune cells, indicating a immune desert tumor microenvironment. The final drug resistant analysis suggested that patients with high expression of LRP11 may be related to the resistance of many anti-tumor drugs. CONCLUSION: LRP11 was a potential oncogene and prognostic marker in cervical cancer and pan-cancer. Patients with high LRP11 expression may have immune desert tumor microenvironment.


Assuntos
Neoplasias do Colo do Útero , Humanos , Feminino , Neoplasias do Colo do Útero/genética , Oncogenes , Bases de Dados Factuais , Mutação , Fatores de Risco , Microambiente Tumoral/genética
6.
Front Surg ; 9: 1030539, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36684211

RESUMO

Objective: The current review was designed to explore if hypoalbuminemia is associated with increased complications in patients undergoing spinal degenerative and deformities surgeries. Methods: The search for eligible studies was conducted on the databases of PubMed, Embase, Web of Science, and CENTRAL up to 20th June 2022. Complication rates were pooled to obtain odds ratio (OR) and 95% confidence intervals. Results: Thirteen studies were included. We found that hypoalbuminemia was significantly associated with increased risk of all complications (OR: 2.72 95% CI: 2.04, 3.63 I 2 = 58% p < 0.00001), mortality (OR: 7.73 95% CI: 3.81, 15.72 I 2 = 0% p < 0.00001), revision surgery (OR: 3.15 95% CI: 1.53, 6.48 I 2 = 87% p = 0.002), readmissions (OR: 1.96 95% CI: 1.29, 2.98 I 2 = 23% p = 0.02), surgical site infections (OR: 2.97 95% CI: 1.90, 4.63 I 2 = 38% p < 0.00001), wound complications (OR: 2.31 95% CI: 1.17, 4.56 I 2 = 48% p = 0.02), pulmonary complications (OR: 3.74 95% CI: 2.66, 5.26 I 2 = 0% p < 0.00001), renal complications (OR: 3.04 95% CI: 1.22, 7.54 I 2 = 0% p = 0.02), cardiac complications (OR: 4.33 95% CI: 2.14, 8.77 I 2 = 0% p < 0.0001), urinary tract infections (OR: 2.08 95% CI: 1.80, 2.41 I 2 = 0% p < 0.00001), and sepsis (OR: 4.95 95% CI: 1.87, 13.08 I 2 = 64% p = 0.01) as compared to those with normal albumin. Conclusion: Hypoalbuminemia is a significant risk factor for complications after spinal degenerative and deformity surgeries. Research is also needed on the role of nutritional support in improving outcomes after spinal degenerative and deformity surgeries. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/, identifier: CRD42022340024.

7.
Materials (Basel) ; 11(3)2018 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-29558438

RESUMO

A novel sintered cutting stainless steel fiber felt with internal channels (SCSSFFC) composed of a stainless-steel fiber skeleton, three-dimensional interconnected porous structure and multiple circular microchannels is developed. SCSSFFC has a jagged and rough surface morphology and possesses a high specific surface area, which is approximately 2.4 times larger than that of the sintered bundle-drawing stainless steel fiber felt with internal channels (SBDSSFFC) and is expected to enhance adhesive strength. The sol-gel and wet impregnation methods are adopted to prepare SCSSFFC with an Al2O3 coating (SCSSFFC/Al2O3). The adhesive strength of SCSSFFC/Al2O3 is investigated using ultrasonic vibration and thermal shock tests. The experimental results indicate that the weight loss rate of the Al2O3 coating has a 4.2% and 8.42% reduction compared with those of SBDSSFFCs based on ultrasonic vibration and thermal shock tests. In addition, the permeability of SCSSFFC/Al2O3 is investigated based on forced liquid flow tests. The experimental results show that the permeability and inertial coefficients of SCSSFFC/Al2O3 are mainly affected by the coating rate, porosity and open ratio; however, the internal microchannel diameter has little influence. It is also found that SCSSFFC/Al2O3 yields superior permeability, as well as inertial coefficients compared with those of other porous materials reported in the literature.

8.
Ecotoxicol Environ Saf ; 73(1): 89-93, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19828196

RESUMO

To investigate the effects of the rare earth element cerium (Ce) on the life span and biomarkers of oxidative stress in the fruit fly (Drosophila melanogaster). Fruit flies were fed on media with different dose of ceric sulfate (1, 4, 16, 64, 256, 1024mg/L, corresponding to cerium concentrations of 0.45, 1.65, 6.91, 26.3, 104, and 429microg/g culture medium). Mean life span, maximum life span, and fertility were calculated. There was a significant decrease in mean life span and maximum life span with increasing doses of cerium. At some concentrations, there was a decrease in reproductive output, especially concentrations >6.91microg/g. We also measured superoxide dismutase (SOD) activity, catalase (CAT) activity, and lipid peroxidation product levels (malondialdehyde (MDA) content). Cerium caused a significant increase in MDA content and decrease in SOD and CAT activities at concentrations >6.91microg/g. These results suggest that cerium may result in oxidative toxicity to D. melanogaster.


Assuntos
Cério/toxicidade , Drosophila melanogaster/efeitos dos fármacos , Longevidade/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Animais , Catalase/metabolismo , Relação Dose-Resposta a Droga , Drosophila melanogaster/metabolismo , Feminino , Fertilidade/efeitos dos fármacos , Masculino , Malondialdeído/análise , Superóxido Dismutase/metabolismo
9.
Taiwan J Obstet Gynecol ; 47(4): 408-11, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19126506

RESUMO

OBJECTIVE: The aim of this study was to determine the complete abortion rate for the vaginal administration of high-dose misoprostol after a failed medical abortion. MATERIALS AND METHODS: When their medical abortions failed after the conventional oral administration of mifepristone and misoprostol, participants then received 1,000 microg of misoprostol vaginally. The efficacy and side effects of this treatment were evaluated. RESULTS: Twenty-seven women who failed to abort after the conventional administration of mifepristone and misoprostol were enrolled in this trial. Fourteen days after the vaginal administration of 1,000 microg misoprostol, the overall complete expulsion rate had reached 88.8% (24/27). Most adverse effects were mild to moderate and did not require treatment. CONCLUSION: The vaginal administration of 1,000 microg misoprostol as a salvage therapy after a failed medical abortion appears to be a safe and highly effective alternative to surgical intervention.


Assuntos
Abortivos não Esteroides/administração & dosagem , Aborto Induzido/métodos , Misoprostol/administração & dosagem , Adolescente , Adulto , Feminino , Idade Gestacional , Humanos , Misoprostol/efeitos adversos , Gravidez , Fatores de Tempo , Resultado do Tratamento , Hemorragia Uterina
10.
Biocell ; 30(1): 27-32, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16845825

RESUMO

The ribosomal DNA (45S rDNA) behaviors during the cell cycle were analyzed on interphase nuclei, prophases, metaphases, pachytene chromosomes and extended DNA fibers in rice (Oryza, sativa ssp. indica cv. Guangluai No.4) by using high-resolution fluorescent in situ hybridization (FISH). The results show that 45S rDNA is located at the ends of short arms of chromosomes 9 and 10. But the signals are much more intense on chromosome 9 than on chromosome 10 in metaphase. Pachytene chromosome has rDNA signal arrays on chromosome 9. Different phases are described and discussed. These results indicate that the activity ofrDNA at individual loci may also vary through the cell cycle in rice. On extended DNA fibers, 45S rDNA signals appear as strings of numerous red spots, but some signals are missed in some regions, probably result from weak signals or intergenic spacers.


Assuntos
DNA de Plantas/genética , DNA Ribossômico/genética , Oryza/citologia , Oryza/genética , Ciclo Celular/genética , Cromossomos de Plantas/genética , Hibridização in Situ Fluorescente
11.
Biocell ; 30(1): 27-32, abr. 2006. ilus
Artigo em Inglês | LILACS | ID: lil-448074

RESUMO

The ribosomal DNA (45S rDNA) behaviors during the cell cycle were analyzed on interphase nuclei, prophases, metaphases, pachytene chromosomes and extended DNA fibers in rice (Oryza,sativa ssp.indica cv.Guangluai No.4) by using high-resolution fluorescent in situ hybridization (FISH). The results show that 45S rDNA is located at the ends of short arms of chromosomes 9 and 10. But the signals are much more intense on chromosome 9 than on chromosome 10 in metaphase. Pachytene chromosome has rDNA signal arrays on chromosome 9. Different phases are described and discussed. These results indicate that the activity of rDNA at individual loci may also vary through the cell cycle in rice. on extended DNA fibers, 45S rDNA signals appear as strings of numerous red spots, but some signals are missed in some regions, probably result from weak signals or intergenic spacers


Assuntos
DNA Ribossômico/genética , Ciclo Celular/genética , Cromossomos de Plantas/genética , DNA de Plantas , Hibridização in Situ Fluorescente , Oryza/citologia , Oryza/genética , China
12.
Biocell ; 30(1): 27-32, abr. 2006. ilus
Artigo em Inglês | BINACIS | ID: bin-121608

RESUMO

The ribosomal DNA (45S rDNA) behaviors during the cell cycle were analyzed on interphase nuclei, prophases, metaphases, pachytene chromosomes and extended DNA fibers in rice (Oryza,sativa ssp.indica cv.Guangluai No.4) by using high-resolution fluorescent in situ hybridization (FISH). The results show that 45S rDNA is located at the ends of short arms of chromosomes 9 and 10. But the signals are much more intense on chromosome 9 than on chromosome 10 in metaphase. Pachytene chromosome has rDNA signal arrays on chromosome 9. Different phases are described and discussed. These results indicate that the activity of rDNA at individual loci may also vary through the cell cycle in rice. on extended DNA fibers, 45S rDNA signals appear as strings of numerous red spots, but some signals are missed in some regions, probably result from weak signals or intergenic spacers(AU)


Assuntos
Ciclo Celular/genética , Cromossomos de Plantas/genética , DNA de Plantas/genética , DNA Ribossômico/genética , Hibridização in Situ Fluorescente , Oryza/citologia , Oryza/genética , China
13.
Biocell ; 30(1): 27-32, abr. 2006. ilus
Artigo em Inglês | BINACIS | ID: bin-119276

RESUMO

The ribosomal DNA (45S rDNA) behaviors during the cell cycle were analyzed on interphase nuclei, prophases, metaphases, pachytene chromosomes and extended DNA fibers in rice (Oryza,sativa ssp.indica cv.Guangluai No.4) by using high-resolution fluorescent in situ hybridization (FISH). The results show that 45S rDNA is located at the ends of short arms of chromosomes 9 and 10. But the signals are much more intense on chromosome 9 than on chromosome 10 in metaphase. Pachytene chromosome has rDNA signal arrays on chromosome 9. Different phases are described and discussed. These results indicate that the activity of rDNA at individual loci may also vary through the cell cycle in rice. on extended DNA fibers, 45S rDNA signals appear as strings of numerous red spots, but some signals are missed in some regions, probably result from weak signals or intergenic spacers(AU)


Assuntos
Ciclo Celular/genética , Cromossomos de Plantas/genética , DNA de Plantas/genética , DNA Ribossômico/genética , Hibridização in Situ Fluorescente , Oryza/citologia , Oryza/genética , China
14.
Yi Chuan ; 28(2): 236-42, 2006 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-16520323

RESUMO

Chromosomes are non-randomly distributed in interphase nucleus, and each chromosome occupies a distinct domain in the chromosome territories (CTs), the positioning and arrangement of CTs are well-organized, at the same time, the chromosome territories have definite dynamics characteristics, the strict positioning and spatial organization of chromosome territories are closely related with gene expression regulation. This paper reviewed progress in these respects.


Assuntos
Cromossomos/genética , Animais , Núcleo Celular/metabolismo , Posicionamento Cromossômico , Humanos , Interfase/fisiologia , Modelos Genéticos
15.
J Formos Med Assoc ; 102(9): 607-12, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14625604

RESUMO

BACKGROUND AND PURPOSE: Reflux esophagitis of Los Angeles grade A or B is more common than grades C and D disease among Taiwanese. This study compared the efficacy of esomeprazole 40 mg and omeprazole 20 mg for starting on-demand therapy for grade A and B reflux esophagitis. METHODS: 100 patients with grade A and B reflux esophagitis were randomized to receive either esomeprazole 40 mg once daily (n = 50) or omeprazole 20 mg once daily (n = 50) for the first 4 weeks. Sustained symptomatic response (SSR) was defined as freedom from symptoms for the last 7 days of the 4-week treatment duration. On-demand therapy was used for the next 4 weeks in patients with SSR; patients without SSR continued with the same proton pump inhibitor regimen. Patients were asked to record their daily severity of acid regurgitation (AR) and heartburn (HB). Medication usage during on-demand therapy was recorded. RESULTS: Forty six patients in the esomeprazole group and 45 patients in the omeprazole group completed the study protocol. The rate of SSR was higher in the esomeprazole group than in the omeprazole group (per-protocol: 73.9% vs 51.1%, p < 0.05; intent-to-treat: 68% vs 46%, p < 0.05). The symptomatic scores for AR and HB were similar between patients taking medication continuously and those taking medication on-demand with both esomeprazole and omeprazole. For patients starting on-demand therapy, the total number of tablets used during 4 weeks was lower in the esomeprazole group than in the omeprazole group (13.5 vs 18.5, p < 0.05). CONCLUSIONS: In patients with grade A and B reflux esophagitis, esomeprazole 40 mg was more effective than omeprazole 20 mg for the initiation of on-demand therapy.


Assuntos
Antiulcerosos/administração & dosagem , Esofagite Péptica/tratamento farmacológico , Omeprazol/administração & dosagem , Esquema de Medicação , Esomeprazol , Esofagite Péptica/classificação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
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