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61.
Objective To investgate the effects of TGF β 3 on rat hepatic fibrosis. Methods The TGF β 3 cDNA was cloned into rAAV2 vector. Rats were randomly divided into four groups: normal control group, model group, negative control group and TGF β 3 group. Hepatic fibrosis was induced by hypodermic injection of 40% CCI4. Recombinant AAV2-TGF β 3 viral particles were injected via the vena caudalis one week before CCh treatment. Rats were executed 8 weeks after CCI4 treatment, global histological change was observed after HE staining, the distribution of the collagen fibers was observed after masson staining, his-tochemistry was done to observe the expression of collagen Ⅰ; The positive area rate of the collagen fibers and the average optical rate of collagen Ⅰ were quantified. Results HE staining indicated that collagen fibers were reduced in the TGF β 3 group. Masson staining shown that the collagen fibers were distributed around the blood vessel, in the portal area and disse space. Compared to the model group (13.2%±2.2%) and negative control group (12.3%±1.5%), the collagen fibers in liver tissues of TGF β3 group (7.7% ± 1.5%) were significantly decreased (q = 9.456, P < 0.01; q = 8.217, P < 0.01). Histochemistry indicated that the collagen fibers of liver tissues of TGF 15 3 group (0.185±0.033) were significantly higher than those in the model group (0.252±0.042) and the negative control group (0.230±0.029), (q = 6.228, P < 0.01; q = 4.346, P < 0.01). Conclusion TGF β 3 alleviates the damage to hepatic cell and the level offibrosis in CCI4 treated rats and inhibits the expression of collagen Ⅰ. 相似文献
62.
本文采用1:3病例对照研究方法,对甾体避孕药的使用与血栓栓塞性疾病(急性心肌梗塞、脑栓塞、脑血栓形成和深静脉血栓形成)间的关联进行多因素分析。结果提示在我国广泛应用的甾体避孕药(主要为国产Ⅰ号避孕药)并不增加血栓栓塞性疾病的危险性。用药和停药时间的长短与血栓栓塞性疾病的发生无关,并与高血压病之间亦不存在协同作用。 相似文献
63.
<正> 患者男性,52岁,突发上腹痛6 h来诊。疼痛呈持续性,无放射痛,无呕吐、腹泻、黄疸。既往有胃溃疡病史。查体:神清,T37.8℃,痛苦面容,平卧位,巩膜皮肤无黄染,心肺(-),上腹部压痛,轻度肌卫,无反跳痛,肝浊音界存在,移动性浊音(-),肠鸣音减弱。化验:WBC12.0×10~9/L、中性0.87。腹 相似文献
64.
目的:探讨局部应用白细胞介素-12(IL-12)对于小鼠皮下肿瘤的治疗作用.方法:小鼠右侧腹部皮下注射2x105 个Panc-02细胞建立皮下肿瘤模型.皮下肿瘤被检测24d,通过测量的皮下肿瘤的两个直径以计算出肿瘤大小(mm2).分为IL-12治疗组和对照组,每组6只小鼠.从第3~7天,IL-2治疗组,每天在肿瘤周围注射0.1 μg IL-12,对照组同时同部注射同量平衡盐水.结果:与对照组相比,IL-12治疗组从第7天开始Panc-02肿瘤的生长出现受到抑制.第10天,IL-12治疗组[(13.8±8.7) mm2]与对照组[(36.4±8.5) mm2],(P<0.05)之间的差异有统计学意义(P<0.05).第24天,两组之间的差异更加明显[(66.5±50.4) mm2 VS (264.4±46.4 )mm2, P<0.01].结论:肿瘤周围注射IL-12明显抑制Panc-02皮下肿瘤的生长,为应用于临床肿瘤治疗提供可能性. 相似文献
65.
QIN Jian LIU Hong-jian DENG Wei WU Guo-zhen CHEN Shu-qing JING Ming-hua 《中国生物医学工程学报(英文版)》2005,14(3):114-119
Based on the fuzzy characteristic of the pulse state and syndromes differentiation thinking mode of TCM, an information fusing recognition method of pulse states based on SFNN (Stochastic Fuzzy Neural Network) is presented in this paper. With the learning ability in parameters and structure, SFNN fuses the measurement information of three pulse-state sensors distributed in Cun, Guan, and Chi location of body for the pulse state recognition. The experimental results show that the percentage of correct recognition with new method is higher than that by single-data recognition one, with fewer off-line train numbers. 相似文献
66.
67.
本文将对呼吸机以下两种常见故障进行简要分析:①呼吸机在抢救病人过程中出现自动切断电源②呼吸机气道口湿度报警。 相似文献
68.
Elizabeth R Seaquist Wei Chen Luke E Benedict Kamil Ugurbil Jae-Hwan Kwag Xiao-Hong Zhu Charles A Nelson 《Journal of cerebral blood flow and metabolism》2007,27(1):154-160
Functional magnetic resonance imaging (fMRI) based on blood oxygen level-dependent (BOLD) contrast has become an invaluable tool in the assessment of in vivo neuronal activation. Quantification of the BOLD response is determined by the hemodynamic and metabolic changes that occur in response to brain stimulation. However, these changes may vary by changes in insulin, a hormone known to be vasoactive in some tissues. To determine if insulin has an effect on fMRI, we measured the BOLD response to a visual stimulus in five normal volunteers in which insulin was first suppressed and then brought to a high physiological concentration. In addition, we also examined the effect of insulin on activation of the visual cortex as measured by the visual-evoked potential (VEP). We found that the BOLD response measured in the presence of insulin (serum insulin=236+/-29 pmol/L) was significantly lower (P<0.001) than that measured in its absence (serum insulin=8+/-2 pmol/L). Insulin was without effect on P100 amplitude or latency acquired in the presence or absence of insulin in 28 subjects using the same stimulus as that used for the fMRI experiments. Our observations suggest that insulin may have effects on cerebral blood flow and/or metabolism that affect the BOLD signal that are independent of its effects on neuronal activation identified by event related potentials (ERP). These findings highlight the complexity that must be considered when interpreting differences in fMRI responses between groups of subjects that differ in insulin concentration and/or insulin sensitivity. 相似文献
69.
笔者通过对270例患者进行尿动力学检查,认为环境、病人的配合程度、检查体位、导管的型号、膀胱灌注情况及护士操作技术、服务态度对尿动力学检查有一定的影响。针对影响因素采取护理措施:积极创造良好的检查环境,加强对患者的宣教与沟通,正确放置体位和选择导管、冲洗液的速度,操作护士熟练的技术和人性化服务,是获得准确检查结果的关键。 相似文献
70.