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91.
92.
随着临床试验数量的增加,系统评价越来越多地被用于分析总结跨学科的科研结果。Meta分析作为一种综合证据的常用方法,能提供总结大量证据的简捷途径,但meta分析不可能适合全部多相性的临床研究,为此,就要用一种定性的方法替代它。总体印象法(Global Impression Method,GIM)作为系统评价中综合多相性临床随机对照试验(Randomized Controlled Trial,RCT)结果的常用方法,作者对其研究现状进行了总结。结果提示,使用总体印象法和最佳证据合成简化版判定森林图的结果与Meta分析的结果存在中等以上程度的内在及交互一致,因此,研究者可用GIM总结RCT结果。经过正常程序以后,在决定证据的精确强度时,个别研究的质量也被考虑,因此,GIM值得在针灸研究中应用。  相似文献   
93.
A multicenter, open-label study was performed to evaluate the safety, anti-hepatitis B virus (anti-HBV) activity, and pharmacokinetics of emtricitabine therapy administered once daily for 8 weeks to patients infected with HBV. Clinical and virologic evaluations were completed at the baseline; at 7, 14, 28, 42, and 56 days during treatment; and at 24, 48, and 28 days posttreatment. Forty-nine patients were enrolled in five dose cohorts (doses of 25, 50, 100, 200, and 300 mg, all of which were administered once daily [q.d.]). Peak plasma emtricitabine concentrations occurred within 1.5 h following dosing. Plasma emtricitabine concentrations (maximum concentrations of drug in plasma and areas under the concentration-time curves) increased nearly dose proportionally over the 25- to 300-mg dose range, with relatively small intersubject variabilities. The plasma half-life of emtricitabine ranged from 6 to 9 h. HBV DNA levels were measured by the Digene HBV Hybrid Capture II assay. Viral suppression (reduction in log(10) serum HBV DNA levels) occurred in all dose cohorts. All doses demonstrated potent and rapid antiviral activities, with a trend toward a greater suppression with daily doses of 100 mg or greater. At 2 months, the median change in the serum HBV DNA level from the baseline level ranged from -1.7 log(10) for the 25-mg dose administered q.d. to -3.3 log(10) for the 300 mg dose administered q.d. Emtricitabine was well tolerated over the 2-month dosing period. These results support further clinical development of emtricitabine for the treatment of chronic hepatitis B infection.  相似文献   
94.

Background

Though secondary data analyses of large datasets may reduce logistical and financial barriers required to perform significant and innovative work, such research requires specialized skills in data handling and statistical techniques as well as thorough and detailed knowledge of the data sources being used.

Objectives

To provide an overview of several common types of secondary data, focusing on strengths, weaknesses and examples of how these data may be used for health services research.

Results

Secondary data comprise a broad and heterogeneous category. This review covers several large categories of such data with examples of their use and discussions about their strengths and weaknesses. Sources include administrative data, claims-based datasets, electronic health records health surveys, patient or disease or both registries, quality improvement initiatives, as well as data from existing trials. Linkages of different types of data may expand the scope of questions answerable using secondary data analysis. Specific strengths and weaknesses of each type of dataset are discussed along with examples from the recent urologic literature.

Conclusions

Choice of the appropriate data source should be tailored to the specific research question as well as the research resources and expertise available. Appropriate decisions about which data to use are the foundation for valid, high-impact research using secondary data.  相似文献   
95.
目的:在心肌缺血再灌注损伤中,炎症细胞因子参与其过程的多个环节。实验拟验证白细胞介素1、白细胞介素8因子在此过程中的动态变化,并分析其与药物干预的关系。方法:实验于2005-10/2006-11在新乡医学院形态学实验室完成。①实验分组:选择健康Wistar成年大鼠70只,按随机数字表法分为3组:对照组(n=10)、模型组(n=30)和药物组(n=30)。后两组又分为缺血0.5h,再灌注2,4,8,12,24h6个时相点,每个时相点5只。对照组只设12h一个时相点作为总体对照。②实验方法:大鼠麻醉后,药物组在右股静脉注入甲泼尼龙(30mg/kg),对照组及模型组注入生理盐水(0.75mg/kg)。采用夹闭左冠状动脉前降支建立大鼠心肌缺血再灌注损伤模型。对照组只开胸不夹闭。③实验评估:在各时相点观察各组大鼠缺血再灌注后的心肌细胞改变;血清学检测白细胞介素1、白细胞介素8因子的动态表达。结果:①模型组缺血再灌注12h炎细胞浸润最显著,药物组炎细胞呈散在浸润。②模型组和药物组白细胞介素1、白细胞介素8因子质量浓度明显高于对照组[缺血再灌注8h为例,白细胞介素1分别为(99.21±14.37),(85.77±11.31),(21.87±10.32)ng/L;白细胞介素8分别为(794.85±24.07),(536.95±19.72),(103.94±11.59)ng/L,P<0.05],峰值分别在缺血再灌注4,8h;同时相点药物组白细胞介素1、白细胞介素8因子质量浓度明显低于模型组(P<0.05)。结论:白细胞介素1和白细胞介素8因子在心肌缺血再灌注损伤的炎症反应中发挥着重要作用;甲泼尼龙对缺血再灌注损伤心肌有保护作用。  相似文献   
96.
目的:利用微持续与微间隔时间技术,设计了两组相关的实验,对亮度知觉效应和视觉加工方式进行探讨。方法:实验于2006-06在中南民族大学物理楼脑认知实验室进行,所有受试者为年龄20~25岁的大学本科生,视力(含矫正视力)正常,均为右利手。①实验1:被试为10名(男5名,女5名),要求被试分别对n屏依次呈现的亮块的明度和n 1屏依次呈现的亮块的明度进行比较(n≤17)。②实验2:被试为28名(男13名,女15名),实验涉及两个刺激物,先呈现的刺激物由左右两个大小相同、亮度不同的亮块a和b组成,后呈现的刺激物把a和b的位置进行对调,当这两个刺激物依次显示时,要求被试报告左右两边的明度是否存在差异,存在何种差异。结果:①实验1∶1≤n≤3时,100%的被试报告,n 1屏的明度大于n屏的亮度,即n 1>n;4≤n≤10时,70%~90%的被试报告n 1>n;n>10时,50%~70%的被试报告n 1>n;随着n值的增加明度差异也在减小,大约在n=17时达到稳定,n屏和n 1屏的明度区别将很难被看出。②实验2:在L(a)b a,随着a和b的亮度差异减小,左右两边呈现的明度越相似;同样当L(a)相似文献   
97.
Purpose: Post-stroke hemiparesis may manifest as asymmetric gait, poor balance, and inefficient movement patterns. We investigated improvements in lower-limb muscle activation and function during Wii-based Movement Therapy (WMT), a rehabilitation program specifically targeting upper-limb motor-function.

Methods: Electromyography (EMG) was recorded bilaterally from tibialis anterior (TA) in 20 stroke patients during a 14-day WMT program. EMG amplitude and burst duration were analyzed during stereotypical movement sequences of WMT activities. Functional movement ability was assessed pre- and post-therapy including 6-min walk test (6MWT), stair-climbing speed, and Wolf Motor Function Test timed-tasks.

Results: TA EMG burst duration during Wii-golf increased by 30% on the more-affected side (p?=?0.04) and decreased by 28% on the less-affected side. Patients who did not step during Wii-tennis had a 16% decrease in more-affected TA burst sum (p?=?0.047) resulting in more symmetrical activation ratio at late-therapy, with the ratio changing from 3.24?±?2.25 to 0.99?±?0.11 (p?=?0.047). Six-minute walk and stair-climbing speed improved (p?=?0.005 and 0.03, respectively), as did upper-limb movement (p?≤?0.001).

Conclusion: This study provides physiological evidence for lower-limb improvements with WMT. Different patterns of muscle activation changes were evident across the WMT activities. Despite the relatively good pre-therapy lower-limb function, muscle activation and symmetry improved significantly with upper-limb WMT.
  • Implications for rehabilitation
  • WMT is an upper-limb neurorehabilitation program that also improves lower-limb motor-function.

  • We report a shift towards more symmetrical muscle activation of tibialis anterior on the more- and less-affected sides that were reflected in increased distance walked during the 6MWT.

  • The use of standing during therapy not only improves lower-limb function but also permits larger and more powerful upper-limb movements.

  • Targeted upper-limb rehabilitation can also significantly improve mobility and balance, whether dynamic or static, that should reduce the risk of falls post-stroke.

  相似文献   
98.
Chronic pain is a common problem requiring a multidisciplinary approach. Nursing can offer diverse therapies complementary to the medical-surgical approach. Guidelines for practice and challenges for research are outlined for selected nonpharmacological chronic pain therapies. This article discusses the placebo effect, which is common to all therapies. Placebos can therapeutically empower patients to stimulate their psychophysiologic self-regulation abilities. Effects, theories, ethics, and therapeutic methods of stimulating the placebo effect are explored.  相似文献   
99.
100.

Background

There is limited evidence supporting the use of local treatment (LT) for prostate cancer (PCa) patients with clinically pelvic lymph node-positive (cN1) disease.

Objective

To examine the efficacy of any form of LT ± androgen deprivation therapy (ADT) in treating these individuals.

Design, setting, and participants

Using the National Cancer Database (2003–2011), we retrospectively identified 2967 individuals who received LT ± ADT versus ADT alone for cN1 PCa. Only radical prostatectomy (RP) and radiation therapy (RT) were considered as definitive LT.

Intervention

LT ± ADT versus ADT alone.

Outcome measurements and statistical analysis

Instrumental variable analyses (IVA) were performed using a two-stage residual inclusion approach to compare overall mortality (OM)-free survival between patients who received LT ± ADT versus ADT alone. The same methodology was used to further compare OM-free survival between patients who received RP ± ADT versus RT ± ADT.

Results and limitations

Overall, 1987 (67%) and 980 (33%) patients received LT ± ADT and ADT alone, respectively. In the LT ± ADT group, 751 (37.8%) and 1236 (62.2%) patients received RP ± ADT and RT ± ADT, respectively. In IVA, LT ± ADT was associated with a significant OM-free survival benefit (hazard ratio = 0.31, 95% confidence interval [CI] = 0.13–0.74, p = 0.007), when compared with ADT alone. At 5 yr, OM-free survival was 78.8% (95% CI: 74.1–83.9%) versus 49.2% (95% CI: 33.9–71.4%) in the LT ± ADT versus ADT alone groups. When comparing RP ± ADT versus RT ± ADT, IVA showed no significant difference in OM-free survival between the two treatment modalities (hazard ratio = 0.54, 95% CI = 0.19–1.52, p = 0.2). Despite the use of an IVA, our study may be limited by residual unmeasured confounding.

Conclusions

Our findings show that PCa patients with clinically pelvic lymph node-positive disease may benefit from any form of LT ± ADT over ADT alone. While not necessarily curative by itself, the use of RP or RT could be the first step in a multi-modality approach aiming at providing the best cancer control outcomes for these individuals.

Patients summary

We examined the role of local treatment for clinically pelvic lymph node-positive prostate cancer. We found that the delivery of radical prostatectomy or radiation therapy may be associated with an overall mortality-free survival benefit compared with androgen deprivation therapy alone.  相似文献   
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