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991.
Isometric and isokinetic torque curves at the knee joint   总被引:1,自引:0,他引:1  
Isometric and isokinetic torques of bilateral quadriceps and hamstrings were measured with Isokinetic Rehabilitation and Testing System (Model No. Cybex 340) on 40 normal untrained subjects, 20 males and 20 females, ranging between the ages of 23 and 35 years. The mean peak isometric and isokinetic torque values of both muscle groups showed no significant differences between dominant (right) and nondominant (left) limbs in both sexes; however there were significant differences between the male and the female. As the angular velocity increased, the peak torque significantly decreased, and the point of peak torque output occurred significantly later in the range of motion for quadriceps and hamstrings (p less than 0.01). There were no significant changes in the hamstrings to quadriceps (H/Q) ratios as the angular velocity increased. However, there were significant differences of mean H/Q ratio between male and female (p less than 0.01). Height had significant positive correlation with peak isometric and isokinetic torques for both quadriceps and hamstrings (p less than 0.01). Weight was found to correlate significantly with peak isometric and isokinetic torques (p less than 0.01). The mean isometric torques were significantly higher than the mean isokinetic torques for any joint angles in both sexes (p less than .01).  相似文献   
992.
To determine the content of thyroglobulin in oxyphilic cells of the thyroid, which have been considered as non-thyroglobulin producing cells, the degree of stainability of the various oxyphilic cells for thyroglobulin was compared with that of non-oxyphilic follicular cells in either same or different lesion. A total of 13 oxyphilic lesions, including three follicular adenomas containing oxyphilic cell nodules, four pure oxyphilic cell adenomas, and six Hashimoto's thyroiditis were compared with 16 of non-oxyphilic lesions such as, seven follicular adenomas, four chronic lymphocytic thyroiditis, and five Graves' disease. Many oxyphilic cells stained positively for thyroglobulin regardless of their morphologic variation, but less intensely than the usual follicular cells in follicular adenomas, chronic lymphocytic thyroiditis, and Graves' disease. The stainability of oxyphilic cells for thyroglogulin did not show any significant correlation with morphologic features, whereas in follicular adenomas, the non-oxyphilic follicular cells forming microfollicles stained less strongly for thyroglobulin than the same cells lining large mature follicles in a reproducible way. With above findings, we concluded that oxyphilic cells maintain the functional activity in terms of thyroglobulin synthesis, although the content of the thyroglobulin is less than that of non-oxyphilic colloid forming follicular cells.  相似文献   
993.
实验以膈肌肌电图(EMGdi)及膈肌诱发电位为指标,观察辅助酶Q10对兔膈肌作用,发现:(1)复制膈肌疲劳(DIF)后静脉注射CoQ10mg/kg,对DIF有治疗作用,(2)提前1静脉注射CoQ1010mg/kg预处理,对电致作膈肌有保护作用。  相似文献   
994.
995.
4-1BB (CDw 137), a member of the tumor necrosis factor receptor (TNFR) superfamily, is a costimulatory receptor primarily expressed on activated T cells. It has been shown that the administration of agonistic anti-4-1BB monoclonal antibody (mAb) enhances tumor immunity and allogenic immune responses. Paradoxically, we found that the administration of anti-4-1BB mAb reduced the incidence and severity of inflammatory bowel disease. In this study, we investigated the effects of anti-4-1BB mAb in a murine intestinal inflammation model, which induced by the hapten reagent, 2,4,6-trinitrobenzene sulfonic acid (TNBS) and mimics immunologic characteristics of human Crohn's disease (CD). Colitis was induced by rectal administration of 2mg of TNBS in 35% ethanol using a vinyl catheter positioned 4cm from the anus. All mice were sacrificed 3 and 10 days after the TNBS administration. The disease activity index (DAI), histological changes of the colon and production of cytokines (IL-2, IL-4, IL-10 and IFN-gamma) were evaluated. The surface molecules of T cells in peripheral blood, spleen and mesenteric lymph nodes were analyzed by flow cytometry. When mice were treated with anti-4-1BB mAb, improvement in both wasting and histopathologic signs of colonic inflammation was observed. The increase a number of splenic CD4(+)CD25(+) T cells and decreased synthesis of the Th1 cytokine IL-2 also occurred. Interestingly, increased production of Th1 cytokine IFN-gamma and proportion of CD8(+) T cells were observed in mice treated with anti-4-1BB mAb in comparison to the colitic mice. These studies show, for the first time, that agonistic anti-4-1BB mAb can improve experimental colitis by reduction of IL-2 and augmentation of CD4(+)CD25(+) regulatory T cells. TNBS colitis is Th1-mediated and has similar histologic features and distribution of inflammation to CD. This study suggests that anti-4-1BB mAb therapy could be effective in the treatment of patients with CD.  相似文献   
996.
目的通过原核表达获得大量脂肪新蛋白质My027,并在体外初步研究其生物活性。方法RT-PCR法扩增出My027片段,插入原核表达载体pGEX-4T-2,构建质粒pGEX-My027。转化BL-21菌,IPTG低温诱导表达融合蛋白,经亲和层析法获得融合蛋白,利用SDS-PAGE、Western印迹及质谱进行鉴定。在还原性谷胱甘肽存在的条件下,将纯化得到的融合蛋白作用于乙二醛酶Ⅰ的底物甲基乙二醛,通过分光光度法检测产物乳酸谷胱甘肽的生成。结果融合蛋白以水溶形式分泌于大肠埃希菌BL-21胞浆中,纯化后的目的蛋白SDS-PAGE、Western印迹及质谱证实高效表达,氨基酸序列正确。结论人脂肪细胞新蛋白质My027在pGEX-4T-2原核表达载体中可获高效表达,所纯化蛋白具有类似于乙二醛酶Ⅰ的作用。  相似文献   
997.
Fu AL  Li Q  Dong ZH  Huang SJ  Wang YX  Sun MJ 《Neuroscience letters》2004,368(3):258-262
Much evidence indicates that the memory and cognitive deficits of patients with Alzheimer's disease are closely associated with dysfunction of central cholinergic system. The degree of reduction of choline acetyltransferase activity in cerebral cholinergic neurons is significantly correlated with the severity of dementia or cognitive impairments observed in Alzheimer's disease. Therefore, Alzheimer's disease may be slowed by supplementation of exogenous choline acetyltransferase. Here we show that choline acetyltransferase mediated by TAT protein transduction domain passes through the blood-brain barrier and enters the neurons in mice, increasing choline acetyltransferase and neurotransmitter acetylcholine contents. The recombination TAT-choline acetyltransferase fusion protein injected intravenously improves the memory and cognitive dysfunction in Alzheimer's disease model mice induced by amyloid-beta peptide. Our results imply a novel and potentially effective way for Alzheimer's disease therapy.  相似文献   
998.
目的:构建最近克隆的人era基因的定点突变体。方法:利用数据库对era的结构特点进行分析,在此基础上用改良的重叠延伸法分别构建人EraN端和C端的定点突变体。结果:获得了分别针对人EraN端TGP结合结构域(位于29-36氨基酸残基)和C端具有RNA结合活性的 KH结构域(位于297-340氨基酸残基)的定点突变体。结论:人era定点突变体的构建为进一步的功能研究奠定了基础。  相似文献   
999.
目的:探索出晚期糖尿病肾病患者在血液透析过程中,如何减少并发症,提高对并发症的疗效,延长存活寿命,提高生活质量.方法:除应用一般性碳酸盐透析外,采用不同透析技术,重点对充血性心力衰竭、心包炎、高血压、低血压、贫血以及胰岛素的使用提出了特殊治疗方案.结果:经采取不同透析技术,提高了对并发症的疗效,提高了病人生活质量,降低了死亡率.结论:对晚期糖尿病肾病患者,尽量做到早透析,透析个体化,根据病情采取不同治疗方案,这是减少并发症提高存活率的关键.  相似文献   
1000.
艾滋病的致病因子为人免疫缺陷病毒。该病毒的蛋白酶在病毒复制和成熟中具有决定性的意义。由于目前国内外尚未获得艾滋病病毒蛋白酶高效表达的重组子及简便的活性检测系统,限制了它的研究与应用。本文将用PCR技术修饰的HIVPr基因克隆入原核高效表达载体pTTQ18的EcoRⅠ和HindⅢ酶切位点之间,并用豆芽核酸酶将EcoRⅠ的粘端削平,构建了读框正确的表达载体,IPTG诱导表明,该重组子在大肠杆菌中获得了高表达,激光扫描结果表明:重组的HIVPr占细菌总蛋白8.9%以上。  相似文献   
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