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991.
Aims/IntroductionOverweight and obesity in adults are strongly associated with an increased risk of prediabetes, and this study set out to gain a better understanding of the optimal body mass index (BMI) range for assessing the risk of prediabetes in the Chinese population.Materials and MethodsThe cohort study included 100,309 Chinese adults who underwent health screening. Participants were divided into six groups based on the cut‐off point for BMI recommended by the World Health Organization (underweight: <18.5 kg/m2, normal‐weight: 18.5–24.9 kg/m2, pre‐obese: 25.0–29.9 kg/m2, obese class I: 30.0–34.9 kg/m2, obese class II: 35.0–39.9 kg/m2, and obese class III ≥40 kg/m2). The association of BMI with prediabetes and the shape of the correlation were modeled using multivariate Cox regression and restricted cubic spline regression, respectively.ResultsIn the multivariate Cox regression model, with normal weight as the control group, underweight people had a lower risk of developing prediabetes, whereas obese and pre‐obese people had a higher risk of prediabetes. Additionally, in the restricted cubic spline model, we found that the association of BMI with prediabetes follows a positive dose–response relationship, but does not conform to the pattern of obesity paradox. Among the general population in China, a BMI of 23.03 kg/m2 might be a potential intervention threshold for prediabetes.ConclusionsThe national cohort study found that the association of BMI with prediabetes follows a positive dose–response relationship, rather than a pattern of obesity paradox. For Chinese people with normal weight, more attention should be paid to glucose metabolism when BMI exceeds 23.03 kg/m2.  相似文献   
992.
目的 探讨护士工作繁荣对教练型领导与职业成长关系的中介效应。方法 采用多阶段分层抽样法,选择河南省7所三级甲等医院的447名护士为研究对象,使用护士职业成长量表、教练型领导感知评价量表(护士他评版)和工作繁荣量表进行调查。结果 护士评估的教练型领导评分为69.61±19.17,工作繁荣评分为49.93±10.12,职业成长评分为49.00±10.07,三者之间互为正相关(均P<0.05)。分层回归分析结果显示,在控制一般资料变量后,教练型领导及工作繁荣能解释职业成长总变异的38.2%。工作繁荣在教练型领导与职业成长之间起中介作用,中介效应占总效应的52.560%。结论 教练型领导有助于提升临床护士工作繁荣水平,进而促进其职业成长,提示护理管理者施展教练型领导以挖掘护士职业发展潜力。  相似文献   
993.
A 63-year-old man with an 8-year history of proteinuria was diagnosed with nephrotic syndrome, and a renal biopsy was performed. Light and electron microscopic analyses showed classic features of idiopathic membranous nephropathy (IMN). However, immunofluorescence tests revealed solitary polyclonal granular IgA deposition along the glomerular capillary walls, rather than IgG, which is often dominant in IMN. The combined use of corticosteroids and calcineurin inhibitor was noticeably effective in reducing proteinuria and improving edema in the current case. Two additional rare cases of IMN with solitary IgA deposition were reviewed, and long-term surveillance is still warranted to characterize its clinicopathological features and outcome.  相似文献   
994.
Glioblastoma multiform (GBM) is a highly aggressive primary brain tumor. Exosomes derived from glioma cells under a hypoxic microenvironment play an important role in tumor biology including metastasis, angiogenesis and chemoresistance. However, the underlying mechanisms remain to be elucidated. In this study, we aimed to explore the role of connexin 43 on exosomal uptake and angiogenesis in glioma under hypoxia. U251 cells were exposed to 3% oxygen to achieve hypoxia, and the expression levels of HIF-1α and Cx43, involved in the colony formation and proliferation of cells were assessed. Exosomes were isolated by differential velocity centrifugation from U251 cells under normoxia and hypoxia (Nor-Exos and Hypo-Exos), respectively. Immunofluorescence staining, along with assays for CCK-8, tube formation and wound healing along with a transwell assay were conducted to profile exosomal uptake, proliferation, tube formation, migration and invasion of HUVECs, respectively. Our results revealed that Hypoxia significantly up-regulated the expression of HIF-1α in U251 cells as well as promoting proliferation and colony number. Hypoxia also increased the level of Cx43 in U251 cells and in the exosomes secreted. The uptake of Dio-stained Hypo-Exos by HUVECs was greater than that of Nor-Exos, and inhibition of Cx43 by 37,43gap27 or lenti-Cx43-shRNA efficiently prevented the uptake of Hypo-Exos by recipient endothelial cells. In addition, the proliferation and total loops of HUVECs were remarkably increased at 24 h, 48 h, and 10 h after Hypo-Exos, respectively. Notably, 37,43gap27, a specific Cx-mimetic peptide blocker of Cx37 and Cx43, efficiently alleviated Hypo-Exos-induced proliferation and tube formation by HUVECs. Finally, 37,43gap27 also significantly attenuated Hypo-Exos-induced migration and invasion of HUVECs. These findings demonstrate that exosomal Cx43 contributes to glioma angiogenesis mediated by Hypo-Exos, and suggests that exosomal Cx43 might serve as a potential therapeutic target for glioblastoma.  相似文献   
995.
Wire and arc additive manufacturing (WAAM) is a competitive technique, which enables the fabrication of medium and large metallic components. However, due to the presence of coarse columnar grains in the additively manufactured parts, the resultant mechanical properties will be reduced, which limits the application of WAAM processes in the engineering fields. Grain refinement and improved mechanical properties can be achieved by introducing ultrasonic vibration. Herein, we applied ultrasonic vibration to the WAAM process and investigated the effects of wire feed speed, welding speed, and ultrasonic amplitude on the weld formation and grain size during ultrasonic vibration. Finally, a regression model between the average grain size and wire feed speed, welding speed, and ultrasonic amplitude was established. The results showed that due to the difference in heat input and cladding amount, wire feed speed, welding speed, and ultrasonic amplitude have a significant influence on the weld width and reinforcement. Excessive ultrasonic amplitude could cause the weld to crack during spreading. The average grain size increased with increasing wire feed speed and decreasing welding speed. With increasing ultrasonic amplitude, the average grain size exhibited a trend of decreasing first and then increasing. This would be helpful to manufacture parts of the required grain size in ultrasonic vibration-assisted WAAM fields.  相似文献   
996.
In this paper, we investigate the spin–orbit torque and transport property in a 2D Rashba ferromagnetic electron gas. The longitudinal conductivity can be divided into two parts: the first term is determined by the charge density and is independent of the spin degrees of freedom. The second term depends on the two bands that spin in the opposite directions, and it is directly proportional to spin–orbit torque regardless of the band structure and temperature. This is a general and underlying relation between the transport property and spin–orbit torque. Moreover, we show the impacts of the spin–orbit coupling constant and Fermi energy on transverse conductivity and spin–orbit torque, which is helpful for relevant experiments.  相似文献   
997.
民国时期上海主要中医药团体简介   总被引:1,自引:0,他引:1  
在评价近代上海的中医活动及其影响时,中医团体的地位不容忽视。上海是我国最先创办中医团体的地区。在20世纪前半叶的近50年中,上海的中医团体活动十分活跃,具有创办时间早,组织规模大,团体数量多,活动影响广等特点,其辐射出的作用和影响在近代我国的中医发展史中也扮演着十分重要的角色。  相似文献   
998.
999.
目的 分析血药浓度监测(TDM)优化美罗培南治疗老年脓毒血症的临床疗效。方法 选择2021年1月至2022年2月我院收治的脓毒血症老年患者64例,随机分为对照组31例,观察组33例。对照组接受常规美罗培南治疗,观察组接受TDM优化美罗培南,对比治疗1周后两组病情变化、生化指标、肺功能、实验室指标与不良反应等。结果 治疗1周后,观察组APACHEⅡ评分/SOFA评分低于对照组(P<0.05),观察组肌酐、胆红素、AST、ALT、EVLW、PVPI下降(P<0.05),观察组白细胞、降钙素原、C-反应蛋白水平低于对照组(P<0.05),观察组美罗培南药物谷浓度与峰浓度高于对照组(P<0.05),观察组PK/PD参数最低抑菌浓度(MIC)为1、2、4时血清药物浓度高于MIC的时间(%T>MIC)优于对照组(P<0.05)。结论 65岁以上老年脓毒血症患者,实施TDM优化美罗培南治疗,可降低病情严重水平,调控机体生化指标、炎症指标,提高药物抗菌活性、药物有效浓度,改善患者肺功能,减少药物不良反应,具有临床意义。  相似文献   
1000.
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