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81.
Proprioception plays an integral role in neuromotor control of the knee joint and deficits in knee joint proprioception are well documented in individuals with knee osteoarthritis (OA). However, the functional relevance of these deficits is not clear. This cross-sectional study evaluated the relationship between knee joint proprioception and pain and disability in a large cohort of individuals with knee OA. Two hundred and twenty participants (145 F, 75 M) with symptomatic knee OA were recruited from the community. Five non-weight bearing active tests with ipsilateral limb matching responses were performed at 20 degrees and 40 degrees flexion to measure knee joint position sense. Pain and disability were assessed by self-reported questionnaires and objective measures of balance and gait. Results showed little association between knee joint position sense variables and measures of pain and disability (r values <0.24, most p>0.05). When comparing participants with the worst and best joint position sense, no significant differences in pain and disability could be found (p>0.05). While our study design does not allow causality to be established, these results suggest that deficits in joint position sense may be due to factors other than pain and that deficits are not large enough to impact upon disability.  相似文献   
82.

Background  

Within cluster randomized trials no algorithms exist to generate a full enumeration of a block randomization, balancing for covariates across treatment arms. Furthermore, often for practical reasons multiple blocks are required to fully randomize a study, which may not have been well balanced within blocks.  相似文献   
83.
[目的]探讨头环牵引外固定架治疗颈椎外伤的临床疗效。[方法]从1997年2月~2005年7月共收治129例颈椎外伤性骨折脱位患者。将129例病例随机分成2组,1组70例行头环牵引,其中31例头环牵引加背心带支架保守治疗,39例头环牵引加手术治疗(前路手术18例,后路手术17例,前后路联合手术4例);另1组59例行颅骨牵引,其中13例颅骨牵引加支具保守治疗,46例颅骨牵引加手术治疗(前路手术22例,后路手术20例,前后路联合手术4例)。[结果]随访6~48个月,平均12个月。头环牵引与颅骨牵引对上颈椎骨折脱位的复位作用无明显差异;对下颈椎骨折脱位的复位作用,统计学处理显示头环牵引组要明显好于颅骨牵引组,复位所需时间比颅骨牵引组短,完全复位率高,减压充分,更有利于脊髓功能恢复,治疗后离床时间头环牵引组要短于颅骨牵引组,2组患者治疗前后脊髓功能Frankel分级均有改善。[结论]头环牵引外固定架可改善复位功能,对颈椎的牵引固定作用较颅骨牵引更为坚强稳定,使用安全方便。  相似文献   
84.
腹主动脉球囊阻断技术在骶骨肿瘤切除中的临床评价   总被引:3,自引:0,他引:3  
[目的]探讨应用腹主动脉球囊阻断技术在行骶骨肿瘤切除术中的临床应用价值。[方法]对36例骶骨肿瘤患者切除过程中应用腹主动脉球囊阻断技术(腹主动脉球囊阻断组),复习既往32例骶骨肿瘤应用传统的术前血管栓塞技术切除肿瘤患者(对照组)的临床资料,比较2组手术时间、出血量、并发症发生率、平均住院时间、术后恢复时间及复发率。[结果]腹主动脉球囊阻断组手术时间为(149.19±73.81)min,术中出血量为(826.67±509.11)ml,有2例骶神经损伤,平均住院时间(26.05±7.08)d,术后恢复时间(34.61±8,22)d,半年复发率5.5%,1年复发率11%,2年复发率16%;对照组手术时间为(221.33±45.19)min,出血量为(1652±706.99)ml,有3例骶神经损伤,4例出现局部皮肤缺血性疼痛,1例出现性功能障碍。平均住院时间(37.93±7.63)d,术后恢复时间(46.03±9.67)d,半年复发率18%,1年复发率31%,2年复发率40.6%。两者比较有显著性差异(P<0.05)。[结论]在骶骨肿瘤过程中,采用腹主动脉球囊阻断技术,可以缩短手术时间,减少出血量及并发症,缩短住院天数,术后恢复快,降低了复发率。是一项具有实用价值的临床技术。  相似文献   
85.
目的探讨危重病患者是否存在高胰岛素血症、胰岛素抵抗(IR)及与肿瘤坏死因子(TNF-α)、白细胞介素-6(IL-6)的关系.方法测定危重病患者123例和对照组30例的空腹血糖(FBG)、空腹胰岛素(FINS)、TNF-α、IL-6的水平,并计算胰岛素敏感性指数(IAI),以评估危重病患者IR的严重程度,并分析各参数之间的相关性.结果危重病组与对照组的IAi分别为-1.95±0.38和-1.5±0.29,两者差异显著(P<0.01).危重病按病因分组后各组IAI相比无显著差异(P>0.05).IAI与危重病严重程度、TNF-α及IL-6的直线回归分析,直线关系r分别为0.86,-0.89,-0.87,差异有显著性(P<0.01).结论危重病患者存在高胰岛素血症及IR.IR的程度与危重病程度、TNF-α、IL-6的水平有显著相关性.危重病患者的IR与TNF-α的升高有关,提示IAI可作为危重病患者病情严重程度的预测指标.  相似文献   
86.
This paper considers the immediate post‐traumatic reactions of rescue personnel who were exposed to the Hilton Hotel bombing in Sinai. The entire rescue personnel (n = 26) were assessed and separated into two groups on the basis of previous exposure to the same type of trauma. The results suggest that among rescue personnel, those with previous exposure had a lower level of post‐traumatic symptoms than those who were being exposed for the first time. This supports the hypothesis that previous exposure to the same type of trauma has an immunizing effect for subsequent same type of traumatic event among rescue personnel. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
87.
It has become increasingly apparent that resident fish can develop resistance to chemicals in their environment, thus compromising their usefulness as sentinels of site-specific pollution. By using a stream system whose resident fish appear to have developed pollutant resistance (Brammell et al., Mar Environ Res 58:251–255, 2005), we tested the hypothesis that the pollutant-inducible biomarker, cytochrome P4501A (CYP1A), as measured in field-caged juvenile rainbow trout (Oncorhynchus mykiss), would reflect relative pollution differences between reference and polychlorinated biphenyl (PCB)-contaminated sites. Trout were caged in the Town Branch/Mud River system (Logan County, KY), a stream system undergoing remediation for PCBs. Fish were held in remediated (Town Branch), unremeditated (Mud River), and reference sites for 2 weeks during spring 2002. At the end of this period, gill and hepatic CYP1A expression were measured. To evaluate the relative PCB exposure of caged trout and provide a reference point against which to calibrate CYP1A response, PCB levels were quantified in sediments from each site. Hepatic CYP1A expression in caged trout clearly detected the presence of PCBs in the Town Branch/Mud River stream system. Sediment PCB levels and hepatic CYP1A expression in caged trout produced identical pollution rankings for the study sites. Gill CYP1A expression, although suggestive of site differences, was not statistically different among sites. Unlike resident fish, which failed to show site differences in hepatic CYP1A expression in this waterway (Brammell et al. 2005), caged fish proved to be a sensitive discriminator of relative PCB contamination in this system. In summary, we determined that CYP1A expression in caged fish reflected relative in situ pollutant exposure. The exposure paradigm confirmed that 2 weeks was a sufficient caging period for evaluating CYP1A response in this species at these temperatures (13–19°C). In addition, these studies demonstrate that tissue-specific CYP1A expression can provide insights into likely routes of exposure. We conclude that CYP1A expression in caged trout is a reliable and inexpensive first-pass determination of relative environmental pollutant exposure and bioavailability in aqueous systems.  相似文献   
88.
外科手术对心肌缺血的血运重建是目前治疗心肌缺血性疾病的重要手段之一。术中准确判断心肌缺血范围及程度和严密监测心脏停跳后心肌细胞损伤是否加重,对于血运重建的准确性,更好地实施心肌保护及对手术疗效的评估和术后处理方案的拟定有着重要意义。因此,如何在术中判断心肌缺血的损伤程度和范围具有极为重要的实验研究意义与临床现实意义。光学相干层析成像作为一种新颖的成像技术,能对活体组织内部微小结构进行实时、在体、高分辨率断层成像。  相似文献   
89.
Pradeep J Nathan  Andrew H Kemp  Ben J Harrison 《Neuropsychopharmacology》2003,28(7):1383; author reply 1384-1383; author reply 1385
  相似文献   
90.
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