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71.
The Chinese National Twin Registry (CNTR) currently includes data from 61 566 twin pair from 11 provinces or cities in China. Of these, 31 705, 15 060 and 13 531 pairs are monozygotic, same‐sex dizygotic and opposite‐sex dizygotic pairs, respectively, determined by opposite sex or intrapair similarity. Since its establishment in 2001, the CNTR has provided an important resource for analysing genetic and environmental influences on chronic diseases especially cardiovascular diseases. Recently, the CNTR has focused on collecting biologic specimens from disease‐concordant or disease‐discordant twin pairs or from twin pairs reared apart. More than 8000 pairs of these twins have been registered, and blood samples have been collected from more than 1500 pairs. In this review, we summarize the main findings from univariate and multivariate genetic effects analyses, gene–environment interaction studies, omics studies exploring DNA methylation and metabolomic markers associated with phenotypes. There remains further scope for CNTR research and data mining. The plan for future development of the CNTR is described. The CNTR welcomes worldwide collaboration.  相似文献   
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Background

Although it is known that women do not participate in trials as frequently as men, there are limited recent data examining how women recruitment has changed over time.

Methods

We conducted MEDLINE search using a validated strategy for randomized trials published in New England Journal of Medicine, Lancet, and Journal of the American Medical Association between 1986 and 2015, and included trials evaluating pharmacologic or nonpharmacologic therapies. We abstracted data on demographics, intervention type, clinical indication, and trial design characteristics, and examined their relationships with women enrollment.

Results

In total, 598 trials met inclusion criteria. Women enrollment increased significantly over time (21% between 1986 and 1990 to 33% between 2011 and 2015; Pfor trend < 0.001) and did not differ by journal or funding source. Women enrollment varied with clinical indication, comprising 37% for non–coronary artery disease vascular trials, 30% for coronary artery disease trials, 28% for heart failure trials, and 28% for arrhythmia trials (P < 0.001), which were all significantly lower than the expected proportion in disease populations (P < 0.001). Women enrollment varied with trial type (31%, 29%, and 26% for pharmacologic, device, and procedural trials, respectively; P = 0.001). These findings were corroborated using multivariable analysis. We found significant positive correlations between women enrolled, and mean age and total number of participants. Fewer women were enrolled in trials reporting statistically significant results than those who did not (P = 0.001).

Conclusions

Although enrollment of women has increased over time, it remains lower than the relative proportion in the disease population. Future studies should elucidate the reasons for persistent under-representation of women in clinical trials.  相似文献   
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目的 了解江苏地区精神专科医院临床女护士主观幸福感的现状及影响因素,为提高精神专科医院的管理水平提供参考依据。方法 采用中文版的“总体幸福感量表”和自制的“一般情况调查表”对江苏省不同地区的6所精神专科医院1260名女护士进行调查。 结果 被调查对象主观幸福感前18项总分为(67.89±14.09)分,处于中等幸福感49~72分之间,但显著低于全国女性常模(71.00±18.00)分,两者比较,t =-2.768,差异有统计学意义(P<0.01);经回归分析,其主要影响因素有对职业伤害的担心程度、家庭的支持程度、收入状况、医院支持系统的满意度,差异均有统计学意义(P<0.01或P<0.05)。结论 江苏地区的精神科女护士主观幸福感总体处于中等水平但显著低于全国女性常模,提高其主观幸福感可以从减少精神科护士的职业伤害、关注家庭方面影响、建立合理的薪酬体系和高效的医院支持系统4个方面努力。  相似文献   
78.

BACKGROUND CONTEXT

Lumbar spinal stenosis (LSS) can impair blood flow to the spinal nerves giving rise to neurogenic claudication and limited walking ability. Reducing lumbar lordosis can increases the volume of the spinal canal and reduce neuroischemia. We developed a prototype LSS belt aimed at reducing lumbar lordosis while walking.

PURPOSE

The aim of this study was to assess the short-term effectiveness of a prototype LSS belt compared to a lumbar support in improving walking ability in patients with degenerative LSS.

STUDY DESIGN

This was a two-arm, double-blinded (participant and assessor) randomized controlled trial.

PATIENT SAMPLE

We recruited 104 participants aged 50 years or older with neurogenic claudication, imaging confirmed degenerative LSS, and limited walking ability.

OUTCOME MEASURES

The primary measure was walking distance measured by the self-paced walking test (SPWT) and the primary outcome was the difference in proportions among participants in both groups who achieved at least a 30% improvement in walking distance from baseline using relative risk with 95% confidence intervals.

METHODS

Within 1 week of a baseline SPWT, participants randomized to the prototype LSS belt group (n=52) and those randomized to the lumbar support group (n=52) performed a SPWT that was conducted by a blinded assessor. The Arthritis Society funded this study ($365,000 CAN) with salary support for principal investigator funded by the Canadian Chiropractic Research Foundation ($500,000 CAN for 5 years).

RESULTS

Both groups showed significant improvement in walking distance, but there was no significant difference between groups. The mean group difference in walking distance was ?74 m (95% CI: ?282.8 to 134.8, p=.49). In total, 62% of participants wearing the prototype LSS belt and 82% of participants wearing the lumbar support achieved at least 30% improvement in walking distance (relative risk, 0.7; 95% CI: 0.5–1.3, p=.43).

CONCLUSIONS

A prototype LSS belt demonstrated significant improvement in walking ability in degenerative LSS but was no better than a lumbar support.  相似文献   
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Hepatic myelopathy is a complication seen in patients with chronic liver failure with physiologic or iatrogenic portosystemic shunting. The main symptom is progressive lower limb dyskinesia. The role of the brain motor control center in hepatic myelopathy is unknown. This study aimed to investigate the gray matter changes in patients with hepatic myelopathy secondary to transjugular intrahepatic portosystemic shunt and to examine their clinical relevance. This was a cross-sectional study. Twenty-three liver failure patients with hepatic myelopathy(hepatic myelopathy group), 23 liver failure patients without hepatic myelopathy(non-hepatic myelopathy group) after transjugular intrahepatic portosystemic shunt, and 23 demographically matched healthy volunteers were enrolled from March 2014 to November 2016 at Xijing Hospital, Air Force Military Medical University(Fourth Military Medical University), China. High-resolution magnetization-prepared rapid gradient-echo brain imaging was acquired. Group differences in regional gray matter were assessed using voxel-based morphometry analysis. The relationship between aberrant gray matter and motor characteristics was investigated. Results demonstrated that compared with the non-hepatic myelopathy group, gray matter volume abnormalities were asymmetric, with decreased volume in the left insula(P = 0.003), left thalamus(P = 0.029), left superior frontal gyrus(P = 0.006), and right middle cingulate cortex(P = 0.021), and increased volume in the right caudate nucleus(P = 0.017), corrected with open-source software. The volume of the right caudate nucleus in the hepatic myelopathy group negatively correlated with the lower limb clinical rating of the Fugl-Meyer Assessment(r = –0.53, P = 0.01). Compared with healthy controls, patients with and without hepatic myelopathy exhibited overall increased gray matter volume in both thalami, and decreased gray matter volume in both putamen, as well as in the globus pallidus, cerebellum, and vermis. The gray matter abnormalities we found predominantly involved motor-related regions, and may be associated with motor dysfunction. An enlarged right caudate nucleus might help to predict weak lower limb motor performance in patients with preclinical hepatic myelopathy after transjugular intrahepatic portosystemic shunt. This study was approved by the Ethics Committee of Xijing Hospital, Air Force Military Medical University(Fourth Military Medical University), China(approval No. 20140227-6) on February 27, 2014.  相似文献   
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