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21.
测定110例肝病的抗凝血酶Ⅲ(AT-Ⅲ)活性,62例低于正常(56.4%),均值为60.1±38.2%。50例正常对照为100.0±26.7%。重症肝炎、慢性活动性肝炎及失代偿期肝硬化活性显著下降,均值分别为12.9±13.0%、51.0±34.6%、43.3±29.6%.AT-Ⅲ活性在评价肝脏功能方面较凝血酶原时间敏感,具有一定的实用意义。 相似文献
22.
目的:探讨胰岛素样生长因子-Ⅰ(IGF-Ⅰ)对软骨细胞增殖及白细胞介素-1(IL-1)诱导软骨细胞凋亡的影响,揭示其抗损伤作用机制,为关节软骨损伤治疗提供理论依据。方法:分离培养人胚胎关节软骨细胞,采用四氮甲基唑蓝(MTT)法测定不同含量软骨细胞增殖活性的变化,利用光镜、电镜、DNA电泳及流式细胞仪测定作为凋亡检测指标。结果:IGF-Ⅰ呈剂量依赖式促软骨细胞增殖,当IGF-Ⅰ含量达50μg/L时,促软骨细胞增殖作用达最大值。IL-1组光镜、电镜下可见典型的细胞凋亡形态学改变,琼脂糖凝胶电泳示特征性的DNA梯状条带,IGF-Ⅰ处理组未见明显凋亡征象。流式细胞仪检测发现,IGF-Ⅰ处理后软骨细胞凋亡率显著降低。结论:IGF-Ⅰ能促进软骨细胞增殖,对IL-1诱导的软骨细胞凋亡具有保护作用。 相似文献
23.
This investigation used a derivation of acoustic reflection (AR) technology to make cross-sectional measurements of changes due to aging in the oral and pharyngeal lumina of male and female speakers. The purpose of the study was to establish preliminary normative data for such changes and to obtain acoustic measurements of changes due to aging in the formant frequencies of selected spoken vowels and their long-term average spectra (LTAS) analysis. Thirty-eight young men and women and 38 elderly men and women were involved in the study. The oral and pharyngeal lumina of the participants were measured with AR technology, and their formant frequencies were analyzed using the Kay Elemetrics Computerized Speech Lab. The findings have delineated specific and similar patterns of aging changes in human vocal tract configurations in speakers of both genders. Namely, the oral cavity length and volume of elderly speakers increased significantly compared to their young cohorts. The total vocal tract volume of elderly speakers also showed a significant increment, whereas the total vocal tract length of elderly speakers did not differ significantly from their young cohorts. Elderly speakers of both genders also showed similar patterns of acoustic changes of speech production, that is, consistent lowering of formant frequencies (especially F1) across selected vowel productions. Although new research models are still needed to succinctly account for the speech acoustic changes of the elderly, especially for their specific patterns of human vocal tract dimensional changes, this study has innovatively applied the noninvasive and cost-effective AR technology to monitor age-related human oral and pharyngeal lumina changes that have direct consequences for speech production. 相似文献
24.
目的 探讨疝环充填式无张力修补术治疗腹股沟疝的经验并评价其临床价值.方法 回顾总结2000年1月至2007年6月疝环充填式无张力修补术治疗腹股沟疝262例临床资料,其中伴随高血压、冠心病、糖尿病、慢性呼吸系统疾病、便秘、前列腺肥大等238例,占90.8%.结果 全组均治愈,手术时间平均41分钟,无切口感染,术后4~7天出院,平均住院5天,随访3~64个月,疝复发1例,为0.4%.结论 该方法操作简便,符合腹股沟区生理解剖特点,强调对高龄患者的术前准备,强调严格的无菌操作,强调充填物放置到位和充填后修补到位是避免术后复发的关键. 相似文献
25.
Serial in vivo MR tracking of magnetically labeled neural spheres transplanted in chronic EAE mice. 总被引:5,自引:0,他引:5
Tamir Ben-Hur Ruud B van Heeswijk Ofira Einstein Michal Aharonowiz Rong Xue Emma E Frost Susumu Mori Benjamin E Reubinoff Jeff W M Bulte 《Magnetic resonance in medicine》2007,57(1):164-171
Neural stem cell (NSC) transplantation has been shown to attenuate the severity of experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). Central to the future success of NSC transplantation in MS is the ability of transplanted cells to migrate from the site of transplantation to relevant foci of disease. Using magnetically labeled mouse neurospheres and human embryonic stem cell (hESC)-derived neurospheres, we applied serial magnetic resonance imaging (MRI) to assess the biodynamics of transplanted cell migration in a chronic mouse EAE model. Magnetic labeling did not affect the in vitro and in vivo characteristics of cells as multipotential precursors. Cell migration occurred along white matter (WM) tracts (especially the corpus callosum (CC), fimbria, and internal capsule), predominantly early in the acute phase of disease, and in an asymmetric manner. The distance of cell migration correlated well with clinical severity of disease and the number of microglia in the WM tracts, supporting the notion that inflammatory signals promote transplanted cell migration. This study shows for the first time that hESC-derived neural precursors also respond to tissue signals in an MS model, similarly to rodent cells. The results are directly relevant for designing and optimizing cell therapies for MS, and achieving a better understanding of in vivo cell dynamics and cell-tissue interactions. 相似文献
26.
观察329块(男193,女136)国人成年跟骨的距关节面形态。其中A型出现率,男为45.08±3.58%,女为41.18±4.22%;B型出现率男为53.89±3.59%,女为58.82±4.22%;C型仅男性出现2例,占1.04±0.73%。成套标本中,距关节面左右对称的,男性90例中有81例,占90.00±3.16%;女性67例中有59例,占88.06±3.96%。经统计学处理,侧别间及性别间均无明显差异。文内结合观察结果提出自己的分型标准及类型,并与以往资料进行了比较。 相似文献
27.
28.
The coronary collateral circulation of goat is very spare, so myocardiac ischemia model of goat can simulate the patient previously with normal coronary circulation and suddenly developing complete occlusion of coronary arteries. In this study 80 Chengdu goats were used, and the branches of their left coronary artery were ligated. Ventricular tachycardia (VT) developed in 23 goats and ventricular fibrillation (VF) in 39 goats. VT and VF both occurred in the early phase of acute myocardial ischemia, and both had 6 min as the median time of onset. In 71 cases data on the weight of myocardiac ischemic area were collected, in which the weight percentage of ischemic area relating to the ventricles of 34 goats with VF was significantly higher than that of 37 goats without VF (35.4 +/- 2.4% vs 19.5 +/- 1.9%). After coronary ligation, 9 cases directly precipitated into VF which could not be defibrillated. In the remaining 62 cases, the weight percentage of ischemic area of 21 cases with VT was higher than that of 41 cases without VT (32.9 +/- 2.8% vs 20.9 +/- 2.1%). The relationships between the incidence of VT or VF and the weight percentage of ischemic area were fitted with logistic curve. The likelihood of occurrence of VT or VF is increased as the weight percentage of ischemia area goes up. 相似文献
29.
本文对44例牙源性脓肿(尖周脓肿24例,牙周脓肿12例,冠周脓肿8例)脓液标本中的产黑色素类杆菌群菌株进行分离、培养、鉴定。其中38例存在产黑菌群,以中间型类杆菌阳性率最高。牙龈类杆菌在牙周脓肿中检出率最高。24例尖周脓肿可分离出6株牙髓类杆菌而其它两种牙源性脓肿则无牙髓类杆菌,推测该菌与牙髓尖周感染的病理过程有关。 相似文献
30.
研究观察年龄对潘库溴铵药代动力学的影响,选择24例施择期整形外科手术的患者,根据年龄分成三组:1组为5例婴幼儿,年龄0.75-2.95岁;2组为13例儿童,年龄4-14岁;3组为6例病人,年龄16-27岁,静注潘库溴铵100ug/kg后用改良蒌光法测定其血浓度,潘库溴铵的体内过程能用二室开放模型完整描述,年龄愈小,分布容积愈大,血浆清除率愈高,潘库溴铵的血药浓度愈低,V1(中央室分布容积),V2(周边室分布容积),Vdss(稳态分布容积),C1(血浆清除率)和AUC(曲线下面积)在三相间有明显差别,1组的T1/2β和MRT明显比2,3组长,但T1/2α和K21在三组间无明显差别。 相似文献