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31.
目的:基质金属蛋白酶在急性心肌梗死后的心室重构中起着重要作用,但其调节机制目前尚未明确。实验拟通过动物模型的建立及体外细胞培养,观察急性心肌梗死后单个核细胞表面CD147与心肌成纤维细胞基质金属蛋白酶-9 mRNA表达的关系。 方法:实验于2006—08/2007-06在河北省人民医院临床实验中心完成。实验材料:SD大鼠及SD仔鼠(出生1~3d)购自河北医科大学试验动物中心。实验过程中对动物处置符合动物伦理学标准。实验方法:①将30只大鼠随机分为急性心肌梗死组(n=15)和假手术组(n=15),假手术组只过线不结扎。流式细胞分析法检测大鼠术后24h外周血单个核细胞表面CD147表达。②选择SD仔鼠制备心肌成纤维细胞。将单个核细胞与心肌成纤维细胞以细胞数0.5:1,1:1,2:1混合培养24h后,半定量反转录一聚合酶联反应法检测基质金属蛋白酶-9 mRNA表达。当单核细胞与心肌成纤维细胞2:1混合时,加入CD147单克隆抗体1,2,4μL/L,培养24h后检测基质金属蛋白酶-9 mRNA表达。 结果:①急性心肌梗死后外周血单个核细胞表面CD147表达明显增加。②单个核细胞与心肌成纤维细胞混合培养,随着单个核细胞比例的增加,心肌成纤维细胞基质金属蛋白酶-9 mRNA表达增加。③在单个核细胞与心肌成纤维细胞2:1混合培养体系中,随着加入CD147单克隆抗体浓度的增加,基质金属蛋白酶-9 mRNA生成减少。 结论:急性心肌梗死后单个核细胞表面CD147表达明显增加,对心肌成纤维细胞基质金属蛋白酶-9生成起上游调节作用。  相似文献   
32.
A history of childhood sexual abuse (CSA) is a risk factor for adult emotional distress, including symptoms of depression, anxiety, dissociation, and trauma. However, CSA is likely associated with adult distress indirectly through an impact on mediating variables. In a review of the empirical literature, the authors found support for the roles of shame or self-blame, interpersonal difficulties, and avoidant coping strategies as mediators. In addition, emotional distress appears to mediate links between CSA and other adverse outcomes, such as alcohol abuse and revictimization. The authors conclude with a number of methodological and conceptual recommendations.  相似文献   
33.
目的:人体助行带为一种随身佩带的动力装置,应用遥测肌电技术测定和分析自行研制的人体助行带的生物力学作用机制。方法:实验于2005-12/2006-06在天津体育大学运动生物力学实验室进行。选取天津市天津医院30名受试对象,均对本实验知情同意。按照生物力学的测试要求,首先对受试者进行5次以上行走状态下的遥测肌电测定,然后在同等条件下对受试者佩带助行带实施对照研究。实验采用的助行带为自行研制的,由腰至足以双层弹力带作为动力装置的弹性结构。结果:行走摆动相大腿肌肌电:佩带助行带后肌内侧肌、肌二头肌、半腱肌肌电高于佩带前(P<0.01)。支撑相小腿肌肌电:佩带助行带后胫前肌、腓骨长肌、腓肠肌肌电高于佩带前(P<0.01)。结论:通过弹力带施加于下肢的外部载荷,能够起到增强下肢肌电以及产生助行的生物力学功效。  相似文献   
34.
目的:总结微创经皮钢板置入内固定治疗胫腓骨骨折的技术操作特点,并观察材料及宿主反应。方法:2004-06/2006-10在济宁医学院附属金乡医院对18例胫腓骨骨折患者在微创手术下进行了手术置入内固定材料。男13例,女5例,年龄17~73岁。术后按Johner-Wruhs方法评价测试各大关节功能,分为优、良、中、差。全部病例进行临床随访。术前、术后1周、6周、3个月、半年及1年分别摄X线片与健侧对比测量患肢外观、成角、旋转和短缩情况,并观察材料及宿主反应。结果:①本组病例切口均顺利愈合,术后3~14d出院。②全部获得随访,平均随访时间14个月;骨愈合时间3~10个月。③按Johner-Wruhs方法评价功能,优13例,良4例,中1例,差0例,以优良为满意标准,本组病例总体满意率94.4%。④术后1例出现跛行步态,中度疼痛,骨成角畸形15°,可能因为患者对不锈钢材料有排斥反应造成固定不牢所致。结论:微创经皮钢板置入内固定材料治疗胫腓骨骨折具有手术创伤小、骨折愈合快、功能恢复好的特点;内固定材料未出现特殊材料反应与宿主反应。  相似文献   
35.

Background

Breast cancer (BC) represents one of the leading causes of cancer related deaths worldwide. New tools for diagnostic staging and therapeutic monitoring are needed to improve individualized therapies and improve clinical outcome. The analyses of circulating tumour cells may provide important prognostic information in the clinical setting.

Materials and methods

Circulating tumour cells (CTC) of 63 BC patients were isolated from peripheral blood (PB) through immunomagnetic separation. Subsequently, RT-PCR or mPCR for the genes ga733.2, muc-1, c-erbB2, mgb-1, spdef and c-erbB2 were performed. Subsequently, expression data were correlated with the tumour stages. Fourteen healthy individuals served as controls.

Results

Significant correlations with tumour stages were found in single gene analyses of ga733.2, muc-1 and in multi-gene analyses of ga733.2/muc-1/mgb1/spdef. Furthermore, a significant correlation of Ca 15-3 and all studied genes was also observed.

Conclusion

Herein, we demonstrated a positive correlation of a gene signature consisting of ga733.2, muc-1, mgb1 and spdef and advanced stages of BC. Moreover, all studied genes and gene patterns revealed a significant correlation with Ca 15-3 positive cases.  相似文献   
36.
37.
Clerodendrum umbellatum Poir (Verbenaceae) is traditionally used in Cameroon for the treatment of many diseases including intestinal helminthiasis. This study was undertaken to assess the in vivo antischistosomal activity of its leaves aqueous extract on a Schistosoma mansoni mice model and to determine the most effective dose of this extract. Mice showing a patent infection of S. mansoni were daily treated with C. umbellatum leaves aqueous extract at the doses of 40, 80 or 160 mg/kg body weight for 14 days. Seven days after administration of the extract, schistosomicidal activity was evaluated on the liver and spleen weights, faecal eggs releasing, liver egg count and worm burden. Treatment using C. umbellatum leaves aqueous extract resulted in an important reduction in faecal egg output by 75.49 % and 85.14 % for 80 mg/kg and 160 mg/kg of the extract respectively. These reduction rates did not differ significantly from the 100 % obtained in the group of infected mice treated with 100 mg/kg of praziquantel. C. umbellatum leaves aqueous extract was lethal to S. mansoni worm. A 100 % reduction rate was recorded in the group of infected mice treated with 160 mg/kg of the extract, as well as in praziquantel-treated mice. An amelioration of the hepatosplenomegaly was noticed in both the extract-treated mice and the praziquantel-treated mice. From these results, we can conclude that C. umbellatum leaves aqueous extract demonstrated schistosomicidal properties in S. mansoni model at doses of at least 80 mg/kg body weight.  相似文献   
38.
A universal model of the lumbar back muscles in the upright position.   总被引:2,自引:0,他引:2  
N Bogduk  J E Macintosh  M J Pearcy 《Spine》1992,17(8):897-913
A model of the lumbar back muscles was constructed incorporating 49 fascicles of the lumbar erector spinae and multifidus. The attachment sites and sizes of fascicles were based on previous anatomic studies, and the fascicles were modeled on radiographs of nine normal volunteers in the upright position. Calculations revealed that the thoracic fibers of the lumbar erector spinae contribute 50% of the total extensor moment exerted on L4 and L5; multifidus contributes some 20%; and the remainder is exerted by the lumbar fibers of erector spinae. At upper lumbar levels, the thoracic fibers of the lumbar erector spinae contribute between 70% and 86% of the total extensor moment. In the upright posture, the lumbar back muscles exert a net posterior shear force on segments L1 to L4, but exert an anterior shear force on L5. Collectively, all the back muscles exert large compression forces on all segments. A force coefficient of 46 Ncm-2 was determined to apply for the back muscles. These results have a bearing on the appreciation of the effects on the back muscles of surgery and physiotherapy.  相似文献   
39.
商陆多糖Ⅰ(PAP-I),0.3~3μg·ml-1和小鼠脾细胞培养3~5d可显著增强其杀伤P815肿瘤细胞活性及IL-2(250~500IU·ml-1)诱导的LAK细胞活性,最适浓度为1μg·ml-1。PAP-I及IL-2和脾细胞培养的上清液对P815肿瘤细胞无细胞毒作用,但能增强脾细胞及LAK细胞杀瘤活性。PAP-I,5,10及50mg·kg-1,ip可增强脾细胞杀伤P815和L929细胞的活性及IL-2诱导的LAK细胞活性。  相似文献   
40.
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