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31.
Patients with mechanic ankle instability experience increased tibiotalar and subtalar joint laxity. However, in vivo joint kinematics in functional ankle instability (FAI) patients and lateral ankle sprain (LAS) copers, especially during dynamic activities, are poorly understood. Ten FAI patients, 10 LAS copers, and 10 healthy controls were included in this study. A dual fluoroscopic imaging system was used to analyze the tibiotalar and subtalar joint kinematics during stair descent. Five key poses of stair descent were analyzed. Kinematic data from six degrees of freedom were calculated utilizing a solid modeling software. The range of motion and joint positions in each degree of freedom were compared among the three groups. The tibiotalar joints of FAI patients and LAS copers were significantly more inverted than those of healthy controls during the foot strike (p = 0.016, = 0.264). The subtalar joints of FAI patients were significantly more anteriorly translated (pose 2, p = 0.003, = 0.352; pose 3, p < 0.001, = 0.454; pose 4, p = 0.004, = 0.334), inverted (pose 4, p = 0.027, = 0.234; pose 5,p = 0.034, = 0.221), and externally rotated (pose 4, p = 0.037, = 0.217; pose 5; p = 0.004, = 0.331) than those of healthy controls during the mid‐stance and the heel off. The FAI patients showed excessive tibiotalar inversion and subtalar joint hypermobility during stair descent. Meanwhile, the LAS copers maintained subtalar joint stability, and only showed excessive tibiotalar inversion in foot strike. These data provide insight into the mechanisms behind the development of FAI after initial LAS. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:1860–1867, 2019  相似文献   
32.
Pulmonary hypertension of the newborn (PHN) constitutes a critical condition with severe cardiovascular and neurological consequences. One of its main causes is hypoxia during gestation, and thus, it is a public health concern in populations living above 2500 m. Although some mechanisms are recognized, the pathophysiological facts that lead to PHN are not fully understood, which explains the lack of an effective treatment. Oxidative stress is one of the proposed mechanisms inducing pulmonary vascular dysfunction and PHN. Therefore, we assessed whether melatonin, a potent antioxidant, improves pulmonary vascular function. Twelve newborn sheep were gestated, born, and raised at 3600 meters. At 3 days old, lambs were catheterized and daily cardiovascular measurements were recorded. Lambs were divided into two groups, one received daily vehicle as control and another received daily melatonin (1 mg/kg/d), for 8 days. At 11 days old, lung tissue and small pulmonary arteries (SPA) were collected. Melatonin decreased pulmonary pressure and resistance for the first 3 days of treatment. Further, melatonin significantly improved the vasodilator function of SPA, enhancing the endothelial‐ and muscular‐dependent pathways. This was associated with an enhanced nitric oxide‐dependent and nitric oxide independent vasodilator components and with increased nitric oxide bioavailability in lung tissue. Further, melatonin reduced the pulmonary oxidative stress markers and increased enzymatic and nonenzymatic antioxidant capacity. Finally, these effects were associated with an increase of lumen diameter and a mild decrease in the wall of the pulmonary arteries. These outcomes support the use of melatonin as an adjuvant in the treatment for PHN.  相似文献   
33.
IntroductionCognitive deficits and neuropsychiatric symptoms occur in parkinsonian and cerebellar subtypes of Multiple System Atrophy (MSA-P and MSA-C). These symptoms have been investigated mainly in cross-sectional studies. The present 1-year follow-up study aimed at evaluating the evolution of cognitive and neuropsychiatric profile in patients with MSA-C and MSA-P.MethodsTwenty-nine patients with MSA-P, 21 with MSA-C and 30 healthy subjects (HCs) underwent a neuropsychological battery and questionnaires assessing depression and apathy (T0). After 1 year (T1), patients with MSA-C and MSA-P underwent the same neuropsychological and neuropsychiatric tools employed at T0.ResultsAt T0, MSA-P and MSA-C groups were more depressed and apathetic and performed worse on tests assessing repetition abilities, executive and attentive functions than HCs. MSA-P and MSA-C groups did not differ on cognitive variables and neuropsychiatric scales. At T1, a significant worsening in spatial planning and psychomotor speed in MSA-C group and a significant worsening in memory, spatial planning, repetition abilities and functional autonomy in MSA-P group were found. The prevalence of apathy increased in both subtypes, whereas the prevalence of depression was reduced in MSA-C and relatively consistent in MSA-P.ConclusionsThe finding revealed a wide-ranging worsening of cognitive functions in MSA-P and a significant decline in processing speed in MSA-C. These results underline the relevance of evaluating cognitive and psychiatric features of MSA over the course of the disease in the daily clinical practice.  相似文献   
34.
目的对医院制剂通鼻消涕颗粒对慢性鼻窦炎鼻黏膜功能是否有调控作用进行临床研究。方法 收集慢性鼻窦炎不伴鼻息肉患者,采用单盲方法随机将患者分为治疗组(通鼻消涕颗粒组)和对照组(克拉霉素片组)。分别给予口服通鼻消涕颗粒和克拉霉素片治疗4周,并对治疗前、治疗2周后、治疗4周后的患者进行糖精试验、鼻部症状VAS评分与鼻内镜Lund Kennedy评分。并采用t检验统计分析。比较服药前、服药后的评分变化。结果 VAS评分提示:治疗组中,治疗2周后、治疗4周后与治疗前相比差异均有统计学意义(P<0.05),对照组在治疗后的各个阶段与治疗前相比均无明显差异(P>0.05)。Lund Kennedy评分提示:治疗组在治疗2周后与治疗前无明显差异,但在治疗4周后有明显改善(P<0.05),对照组则在治疗后各个阶段无明显变化(P>0.05)。糖精试验提示2组在治疗后2周患者糖精清除时间差异无统计学意义(P>0.05),但治疗组在治疗4周后患者糖精清除时间低于对照组(P<0.05)。结论 通鼻消涕颗粒对慢性鼻窦炎的鼻黏膜形态与传输功能有明显改善作用,可以促进鼻黏膜纤毛功能的恢复,并优于克拉霉素片组,且无毒副作用,值得临床上推广应用。  相似文献   
35.
淋巴管作为循环系统的重要组成部分之一,具有调节机体体液稳态,协助免疫监视和肠道脂质吸收等重要作用。淋巴管新生是机体生理和病理过程中维持脉管系统结构和功能正常的重要手段,淋巴管新生调控对于防治肿瘤、心血管等诸多疾病有着潜在的临床转化意义;淋巴回流功能则与关节炎症等疾病发病机制关系密切。在循环系统中,相较于中医药调控血管相关疾病的发病机制已取得很大进展,近年来对于淋巴管的研究则明显相对滞后。本文从中医药作用于淋巴管新生及回流功能角度对这一领域的研究进展作一综述,以期为临床上中医药治疗相关疾病提供新的思路与方法。  相似文献   
36.
This paper investigates the quantized sliding mode control of Markov jump systems with time‐varying delay. A dynamical adjustment law is explored to quantize the system output. By constructing an observer‐based integral sliding surface, a sliding mode controller is designed to take over the dynamical motion of state estimation and ensure the reachability of sliding surface. A new scaling manner is developed to build the bound between the system output and quantized error. With the help of separation strategies for controller synthesis and general transition probabilities and a lower bound theorem for nonlinear integral terms, a new synthesis method to ensure the required stability and meet the required performance is proposed in the form of linear matrix inequalities. The validity of the proposed control method is illustrated by a numerical example.  相似文献   
37.
BackgroundUnequal housing access resulted in more than 150 million homeless people worldwide, with millions more expected to be added every year due to the ongoing climate-related crises. Homeless population has a counterproductive effect on the social, psychological integration efforts by the community and exposure to other severe health-related issues. Geographic Information Systems (GIS) have long been applied in urban planning and policy, housing and homelessness, and health-related research.MethodsWe used the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method to systematically review 24 articles collected from multiple databases (n = 10) that focused on health-related issues among homeless people and used geospatial analysis techniques in their research.ResultsOur findings indicated a geographic clustering of case study locations– 26 out of the 31 case study sites are from the USA and Canada. Studies used spatial analysis techniques to identify hotspots, clusters and patterns of patient location and population distribution. Studies also reported relationships among the location of homeless shelters and substance use, discarded needles, different infectious and non-infectious disease clusters.ConclusionMost studies were restricted in analyzing and visualizing the patterns and disease clusters; however, geospatial analyses techniques are useful and offer diverse techniques for a more sophisticated understanding of the spatial characteristics of the health issues among homeless people. Better integration of GIS in health research among the homeless would help formulate sensible policies to counter health inequities among this vulnerable population group.  相似文献   
38.
的 了解血流感染肺炎克雷伯菌中CRISPR-Cas系统的分布特征并分析其与毒力基因和耐药的关系。方法 收集非重复血流感染肺炎克雷伯菌248株,使用Vitek2-Compact全自动微生物分析系统进行菌株鉴定及药物敏感性分析,PCR检测CRISPR-Cas系统3个相关基因(CRISPR1、CRISPR2和cas1)、筛查6种常见高毒力荚膜血清型(K1、K2、K5、 K20、K54和K57)、12种毒力基因及检测13种耐药基因,用χ2检验比较携带有CRISPR-Cas系统菌株与不携带CRISPR-Cas系统菌株毒力及耐药差异。结果 CRISPR-Cas系统的检出率为29.8%(74/248);K1型是携带CRISPR-Cas系统肺炎克雷伯菌的主要荚膜血清型,占 28.4%(21/74);除kpn基因外,携带CRISPR-Cas系统菌株的毒力基因检出率均大于不携带CRISPR-Cas系统菌株,其中7种差异有统计学意义;除对氨苄西林耐药率达100%外,携带有CRISPR-Cas系统菌株的其他抗菌药物耐药率均小于不携带有CRISPR-Cas系统菌株,其中13种差异有统计学意义;携带CRISPR-Cas系统菌株的耐药基因阳性率小于不携带CRISPR-Cas系统的菌株,且blaKPC、blaSHV、qnrS基因差异有统计学意义。结论 高毒力荚膜血清型肺炎克雷伯菌中主要为K1型携带CRISPR-Cas系统,携带CRISPR-Cas系统的肺炎克雷伯菌相对于不携带CRISPR-Cas系统菌株的毒力基因阳性率高,耐药率低,耐药基因的阳性率低。CRISPR-Cas系统可能能降低耐药基因在肺炎克雷伯菌中的水平传播,尤其是在K1型肺炎克雷伯菌。  相似文献   
39.
A developmental validation was performed to demonstrate reliability, reproducibility and robustness of the ANDE System with the FlexPlex assay, including an integrated Expert System, across a number of laboratories and buccal sample variations. Previously, the related DNAscan™/ANDE 4C Rapid DNA System using the PowerPlex®16 assay and integrated Expert System Software received NDIS approval in March 2016. The enhanced ANDE instrument, referred to as ANDE 6C, and the accompanying 6-dye, 27-locus STR assay, referred to as FlexPlex, have been developed to be compatible with all widely used global loci, including the expanded set of the CODIS core 20 loci.Six forensic and research laboratories participated in the FlexPlex Rapid DNA developmental validation experiments, testing a total of 2045 swabs, including those obtained from 1387 unique individuals. The goal of this extensive and comprehensive validation was to thoroughly evaluate and document the ANDE System and its internal Expert System to reliably genotype reference buccal swab samples in a manner compliant with the FBI’s Quality Assurance Standards and the NDIS Operational Procedures.The ANDE System, including automated Expert System analysis, generated reproducible and concordant results for buccal swabs when testing various instruments at different laboratories by a number of different operators. When testing a number of non-human DNAs, including oral bacteria, the ANDE System and FlexPlex assay demonstrated limited cross-reactivity. Potential PCR inhibitors were evaluated as part of the validation and no inhibition was detected. Reproducible and concordant profiles were generated from buccal swab samples collected with a limit of detection appropriate for buccal swab collections from arrestees. The precision and resolution of the System met industry standards for detection of microvariants and single base resolution.The integrated Expert System appropriately demonstrated the ability to correctly pass or fail profiles for CODIS upload without human review. During this comprehensive developmental validation, the ANDE System successfully interpreted over 2000 samples tested with over 99.99% concordant alleles. The data package described herein led to the ANDE System with the FlexPlex assay receiving NDIS approval in June 2018.  相似文献   
40.
Deep brain stimulation (DBS) in psychiatric illnesses has been clinically tested over the past 20 years. The clinical application of DBS to the superolateral branch of the medial forebrain bundle in treatment‐resistant depressed patients—one of several targets under investigation—has shown to be promising in a number of uncontrolled open label trials. However, there are remain numerous questions that need to be investigated to understand and optimize the clinical use of DBS in depression, including, for example, the relationship between the symptoms, the biological substrates/projections and the stimulation itself. In the context of precision and customized medicine, the current paper focuses on clinical and experimental research of medial forebrain bundle DBS in depression or in animal models of depression, demonstrating how clinical and scientific progress can work in tandem to test the therapeutic value and investigate the mechanisms of this experimental treatment. As one of the hypotheses is that depression engenders changes in the reward and motivational networks, the review looks at how stimulation of the medial forebrain bundle impacts the dopaminergic system.  相似文献   
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