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31.
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   
32.
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   
33.
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   
34.
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   
35.
Concentrations of polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCPs) in ten water samples (four pairs of tap water with source water and two additional tap water) were analyzed and a US EPA algorithm was used to estimate their associated human health risks. Organochlorine pesticides were found in most samples analyzed. Concentrations of total PAHs ranged from 4.8 to 84.4 and 0.7 to 53.8 ng/l, for source and tap water, respectively. Carcinogenic and noncarcinogenic risk assessments were employed for various trace organic pollutants in the tap water. The results indicated that carcinogenic risk for male and female lifetime of tap water from XuZh (XZ) city was higher than the others. XZ located in the northern part of Jiangsu province, which takes ground water as the water source. Children were more vulnerable to the carcinogenic chemicals than adults. Carcinogenic risks for male children (0–14 years old) in XZ were the highest, reaching 3.68 × 10−6. Contribution analysis showed that dibenz[a,h]anthracene contributed most to the carcinogenic risk in XZ city, and α-HCH, β-HCH and γ-HCH posed the most carcinogenic risk in tap water from GoHu (GH) in Eastern Taihu Lake. Additionally, noncarcinogenic risks posed by the detected chemicals to local people were negligible. Risk alleviation strategies should be adopted, taking into account the results of these health risk assessments.  相似文献   
36.
真菌F400属红曲霉属的一种,称为红曲霉F400。它产生一个降胆固醇的活性物质F400。降胆固醇活性及理化性质的比较研究证明,F400与高效降胆固醇药物Lovastatin(Monacolin K)为相同的物质。  相似文献   
37.
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   
38.
AIM: To compare the efficacy of intravitreal ranibizumab (IVR) alone or in combination with photodynamic therapy (PDT) vs PDT in patients with symptomatic polypoidal choroidal vasculopathy (PCV).METHODS: A systematic search of a wide range of databases (including PubMed, EMBASE, Cochrane Library and Web of Science) was searched to identify relevant studies. Both randomized controlled trials (RCTs) and non-RCT studies were included. Methodological quality of included literatures was evaluated according to the Newcastle-Ottawa Scale. RevMan 5.2.7 software was used to do the Meta-analysis.RESULTS: Three RCTs and 6 retrospective studies were included. The results showed that PDT monotherapy had a significantly higher proportion in patients who achieved complete regression of polyps than IVR monotherapy at months 3, 6, and 12 (All P≤0.01), respectively. However, IVR had a tendency to be more effective in improving vision on the basis of RCTs. The proportion of patients who gained complete regression of polyps revealed that there was no significant difference between the combination treatment and PDT monotherapy. The mean change of best-corrected visual acuity (BCVA) from baseline showed that the combination treatment had significant superiority in improving vision vs PDT monotherapy at months 3, 6 and 24 (All P<0.05), respectively. In the mean time, this comparison result was also significant at month 12 (P<0.01) after removal of a heterogeneous study.CONCLUSION: IVR has non-inferiority compare with PDT either in stabilizing or in improving vision, although it can hardly promote the regression of polyps. The combination treatment of PDT and IVR can exert a synergistic effect on regressing polyps and on maintaining or improving visual acuity. Thus, it can be the first-line therapy for PCV.  相似文献   
39.
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   
40.
目的探讨下法的使用禁忌,为临床准确选方用药提供有力依据。方法通过对《伤寒论》中与下法有关的110余条原文进行分析,并结合历代医家相关解析,在理解原文的基础上,对禁用下法的情况进行分类和归纳,以揭示张仲景禁用下法的整体思路。结果禁用下法可分3种情况:(1)无向下病势禁用下法;(2)虚症禁用下法;(3)腑实未成禁用下法。结论临床治疗中,需要使用下法时,应在排除禁忌情况的前提下,综合分析疾病的病势、病位及患者的虚实情况后方可选方用药。  相似文献   
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