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排序方式: 共有8148条查询结果,搜索用时 15 毫秒
21.
Objective: Osteoporosis (OP) is the most common bone disease. The genetic and metabolic factors play important roles in OP development. However, the genetic basis of OP is still elusive. The study aimed to explore the relationships between OP and dietary habits. Methods: This study used large-scale genome-wide association study (GWAS) summary statistics from the UK Biobank to explore potential associations between OP and 143 dietary habits. The GWAS summary data of OP included 9434 self-reported OP cases and 444,941 controls, and the GWAS summary data of the dietary habits included 455,146 participants of European ancestry. Linkage disequilibrium score regression (LDSC) was used to detect the genetic correlations between OP and each of the 143 dietary habits, followed by Mendelian randomization (MR) analysis to further assess the causal relationship between OP and candidate dietary habits identified by LDSC. Results: The LDSC analysis identified seven candidate dietary habits that showed genetic associations with OP including cereal type such as biscuit cereal (coefficient = −0.1693, p value = 0.0183), servings of raw vegetables per day (coefficient = 0.0837, p value = 0.0379), and spirits measured per month (coefficient = 0.115, p value = 0.0353). MR analysis found that OP and PC17 (butter) (odds ratio [OR] = 0.974, 95% confidence interval [CI] = (0.973, 0.976), p value = 0.000970), PC35 (decaffeinated coffee) (OR = 0.985, 95% CI = (0.983, 0.987), p value = 0.00126), PC36 (overall processed meat intake) (OR = 1.035, 95% CI = (1.033, 1.037), p value = 0.000976), PC39 (spirits measured per month) (OR = 1.014, 95% CI = (1.011, 1.015), p value = 0.00153), and servings of raw vegetables per day (OR = 0.978, 95% CI = (0.977, 0.979), p value = 0.000563) were clearly causal. Conclusions: Our findings provide new clues for understanding the genetic mechanisms of OP, which focus on the possible role of dietary habits in OP pathogenesis. 相似文献
22.
Microstructure and Friction Properties of CoCrFeMnNiTix High-Entropy Alloy Coating by Laser Cladding
Pengfei Liu Wudong Si Dabin Zhang Sichao Dai Benchi Jiang Da Shu Lulu Wu Chao Zhang Meisong Zhang 《Materials》2022,15(13)
To enhance the friction and wear properties of 40Cr steel’s surface, CoCrFeMnNi high-entropy alloy (HEA) coatings with various Ti contents were prepared using laser cladding. X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) were used to characterize the phase composition, microstructure, and chemical composition of the samples. The findings demonstrated that the CoCrFeMnNiTix HEA coatings formed a single FCC phase. Fe2Ti, Ni3Ti, and Co2Ti intermetallic compounds were discovered in the coatings when the molar ratio of Ti content was greater than 0.5. The EDS findings indicated that Cr and Co/Ni/Ti were primarily enriched in the dendrite and interdendrite, respectively. Ti addition can effectively enhance the coating’s mechanical properties. The hardness test findings showed that when the molar ratio of Ti was 0.75, the coating’s microhardness was 511 HV0.5, which was 1.9 times the hardness of the 40Cr (256 HV0.5) substrate and 1.46 times the hardness of the CrCrFeMnNi HEA coating (348 HV0.5). The friction and wear findings demonstrated that the addition of Ti can substantially reduce the coating’s friction coefficient and wear rate. The coating’s wear resistance was the best when the molar ratio of Ti was 0.75, the friction coefficient was 0.296, and the wear amount was 0.001 g. SEM and 3D morphology test results demonstrated that the coating’s wear mechanism changed from adhesive wear and abrasive wear to fatigue wear and abrasive wear with the increase in Ti content. 相似文献
23.
基于成熟的脉诊、舌诊信息提取与识别的关键技术,集成便携式辅助诊疗系统突出脉诊、舌诊在中医诊疗中的重要作用,并融合其他四诊信息,实现自动辨证处方的临床辅助诊疗功能。便携式辅助诊疗系统体现了"四诊合参"的中医辨证诊断理念,其便携化、智能化、人性化的特点贴合临床实际,为脉诊、舌诊研究成果的推广应用奠定了完备的条件。 相似文献
24.
Daoqin Liu Chengcheng Yang Ru Zhou Hongjing Zhao Tingwei Si Chunsheng Liu Qiwen Wu 《Journal of clinical laboratory analysis》2022,36(7)
ObjectivesThis study aimed to investigate the effect of hemoglobin (Hb) fluctuation after dialysis on the prognosis of cardiovascular‐related and all‐cause deaths in peritoneal dialysis (PD).MethodsAccording to the Hb fluctuation, patients were divided into low fluctuation group, moderate fluctuation group, and high fluctuation group, and then, the effects of Hb fluctuation after dialysis on the prognosis of cardiovascular‐related and all‐cause death in PD were analyzed by regression analysis.ResultsA total of 232 patients were selected in this study. Compared with the low Hb fluctuation group, the moderate and high fluctuation groups had lower body mass index (BMI), estimated glomerular filtration rate (eGFR), and baseline Hb, and the moderate fluctuation group had less erythropoietin (EPO) and dialysis dose. Compared with survivors, patients with cardiovascular‐related and all‐cause deaths had lower mean Hb and Hb fluctuation (all p < 0.05). Cox regression analysis showed that before and after adjusting for confounding factors, Hb fluctuation was still independently correlated with cardiovascular prognosis, and higher Hb fluctuation was still a protective factor for cardiovascular‐related death in the Hb‐substandard group, but there was no significant correlation between Hb fluctuation and all‐cause death. Multivariate linear regression analysis revealed that Hb fluctuation was positively correlated with Kt/V and EPO dosage, but negatively correlated with the baseline Hb.ConclusionHigh Hb fluctuation was a protective factor for cardiovascular‐related death in PD with substandard Hb. Compared with Hb fluctuation, correction of anemia timely and making Hb reaches the standard level had a greater impact on reducing cardiovascular‐related death in PD. 相似文献
25.
目的:研究地塞米松和组胺对培养的人鼻息肉组织黏蛋白MUC5AC mRNA和蛋白表达的影响。方法:实验分为对照组、组胺刺激组和地塞米松干预组,采用RT-PCR和免疫组织化学技术分别检测鼻息肉组织中MUC5AC mRNA和蛋白的表达。结果:组胺刺激组鼻息肉组织MUC5AC mRNA和蛋白表达分别为0.6389±0.0526和0.1934±0.0137,均较对照组(分别为0.3495±0.0357和0.1172±0.0173)明显增加(均P<0.01),地塞米松抑制后两者均明显降低(分别为0.4988±0.0603和0.1444±0.0075)(均P<0.05)。结论:炎性递质组胺可上调黏蛋白表达;地塞米松可下调黏蛋白表达,这可能是它抑制鼻息肉黏液过度分泌的途径之一。 相似文献
26.
目的 膨体聚四氟乙烯(expanded Polytetrafluoroethylene,e-PTFE)(简称膨体)填塞结合隆鼻手术综合治疗鼻中线低平的严重萎缩性鼻炎,提高疗效并改善患者生理及心理疾患。方法 收集联勤保障部队第九○八医院耳鼻咽喉头颈外科2010年1月至2021年1月期间确诊为萎缩性鼻炎患者50例,A组25例患者全部采用羟基磷灰石填塞法治疗,B组25例患者全部采用膨体填塞结合隆鼻手术综合治疗。采用鼻小柱切口,翻盖式手术切口暴露鼻中隔及鼻底部,在鼻腔内、下壁黏膜下填塞膨体及抬高鼻尖缩窄前鼻孔等综合治疗方法。结果 术后3个月、3~6个月除感染、外露手术失败者,A、B两组患者术后效果无统计学意义(P >0.05),术后6~12个月后随诊B组满意率显著高于A组,鼻腔通气稳定,差异有统计学意义(P<0.05)。结论 膨体填塞结合隆鼻手术综合治疗鼻中线低平的严重萎缩性鼻炎,较唇龈切口黏骨膜下填入羟基磷灰石,长期效果稳定,患者满意度高,使用范围及前景更大,值得临床推广。 相似文献
27.
28.
Omar SZ Qvist R Khaing SL Muniandy S Bhalla S 《The journal of obstetrics and gynaecology research》2008,34(2):174-178
AIM: The aim of the present study was to determine the existence or prevalence of thrombophilic markers such as Factor V Leiden, prothrombin G20210A, protein S, protein C, activated protein C and anti-thrombin in pre-eclampsia and pregnancy-induced hypertensive patients. METHODS: Blood samples were collected from a total number of 124 women at the maternity unit, University of Malaya Medical Center. These included 49 patients with pre-eclampsia, 63 patients with pregnancy-induced hypertension and 12 normal pregnant women. DNA was extracted from the blood samples. Factor V Leiden (Taq I) and prothrombin G20210A (Hind III) genotyping was done on polymerase chain reaction-restriction fragment length polymorphism. Anti-thrombin activity and the concentrations of protein C, protein S and activated protein C were measured using the IL Coagulation System (Hemosil). RESULTS: Of the 124 subjects, one pre-eclampsia patient was homozygous for Factor V Leiden mutation but prothrombin G20210A mutation was not present in any of the subjects. The subject with Factor V Leiden mutation also had a low activated protein C resistance and a low protein S concentration. CONCLUSIONS: Factor V Leiden mutation is present in the Asian population and may very well serve as one of the genetic factors responsible for pre-eclampsia and other adverse pregnancy outcomes. 相似文献
29.
30.
Shuting Si Zhicheng Peng Haoyue Cheng Yan Zhuang Peihan Chi Xialidan Alifu Haibo Zhou Minjia Mo Yunxian Yu 《Nutrients》2022,14(12)
The association between vitamin D and hemoglobin has been suggested. Vitamin D can affect erythropoiesis by the induction of erythroid progenitor cell proliferation and enhance iron absorption by regulating the iron-hepcidin-ferroportin axis in monocytes. However, this relationship in pregnant women is scarce. The purpose of this study was to investigate the association between plasma vitamin D levels with hemoglobin concentration in pregnant women considering each trimester and iron supplementation. The data were obtained from Zhoushan Pregnant Women Cohort, collected from 2011 to 2018. Plasma 25(OH)D was measured in each trimester using liquid chromatography–tandem mass spectrometry. Generalized estimating equations and multiple linear regressions were performed. Finally, 2962 pregnant women and 4419 observations in the first trimester were included in this study. Plasma 25(OH)D in first trimester (T1) (β = 0.06, p = 0.0177), second trimester (T2) (β = 0.15, p < 0.0001), and third trimester (T3) (β = 0.12, p = 0.0006) were positively associated with Hb. Association between plasma 25(OH)D levels in T1 and Hb concentration was positively associated with gestational age (β = 0.005, p = 0.0421). Pregnant women with VD deficiency in T1 (OR = 1.42, 95% CI: 1.07–1.88) or T2 (OR = 1.94, 95% CI: 1.30–2.89) presented an increased risk of anemia, compared with women without VD deficiency. Moreover, the significant relationship between VD and Hb was only observed among women with iron supplementation during pregnancy. Plasma 25(OH)D levels in each trimester were positively associated with Hb concentration. Iron supplementation might be an important factor affecting the relationship between VD and Hb. 相似文献