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141.
目的 观察腹腔镜胆囊切除术 (LaparoscopicCholecystectomy ,L .C)后钛夹在腹腔内异位。方法 前瞻性对2 0 0 2年 1~ 5月间 6 0例L .C病人进行追踪观察临床表现 ,采用B超、腹部X线检查等方法 ,观察钛夹位置的变化与肝外胆管的关系。结果 6 0例L .C后病人中 5例钛夹发生位置改变。结论 ①钛夹在体内 ,对胆道无压迫、无胆漏 ;②观察钛夹异位 ,以采用B超为最简单、经济的方法。 相似文献
142.
滑环是螺旋CT最基本的部件之一,承担着扫描架中固定与旋转部件之间的供电、接地及信息传递等功能,并介绍了滑环的基本结构、故障检修及维护. 相似文献
143.
目的研究超顺磁性氧化铁(superparamgnetic iron oxides,SPIOs)标记神经干细胞及其生物学特性.方法:神经干细胞培养、传代和诱导分化;Resovist(一种SPIOs)标记神经干细胞。制备磁标记神经干细胞;利用免疫细胞化学、透射电镜和Prussian blue染色等方法对磁标记神经干细胞生物学特性进行研究。结果:在原代及传代细胞中有Nestin阳性细胞即神经干细胞.血清诱导下,神经干细胞可分化为GFAP、NF200阳性细胞.Resovist与神经干细胞共同孵育后,透射电镜及Prussian blue染色显示胞浆中含有铁颗粒,Resovist也可以随细胞的分裂增殖而传到子代细胞中。随Resovist浓度的增高(5.6μg/ml-11.2μg/ml),Resovist对神经干细胞存活、分化能力的影响无显著性差异(P〉0.05).当Resovist的浓度大于22.4μg/ml时。Resovist影响其存活和分化(P〈0.05)。结论:本实验利用Resovist作为磁标记探针,对神经干细胞进行成功磁标记,为进一步利用核磁共振(MRI)对神经干细胞活体追踪奠定实验基础。 相似文献
144.
145.
Emiri Tejima Bing-Qiao Zhao Kiyoshi Tsuji Anna Rosell Klaus van Leyen R Gilberto Gonzalez Joan Montaner Xiaoying Wang Eng H Lo 《Journal of cerebral blood flow and metabolism》2007,27(3):460-468
We tested the hypothesis that astrocytic matrix metalloproteinase-9 (MMP-9) mediates hemorrhagic brain edema. In a clinical case of hemorrhagic stroke, MMP-9 co-localized with astrocytes and neurons in peri-hematoma areas. In a mouse model where blood was injected into striatum, MMP-9 was colocalized with astrocytes surrounding the hemorrhagic lesion. Because MMP-9 is present in blood as well as brain, we compared four groups of wild type (WT) and MMP-9 knockout (KO) mice: WT blood injected into WT brain, KO blood into KO brain, WT blood into KO brain, and KO blood into WT brain. Gel zymography showed that MMP-9 was elevated in WT hemorrhagic brain tissue but absent from KO hemorrhagic brain tissue. Edematous water content was elevated when WT blood was injected into WT brain. However, edema was ameliorated when MMP-9 was absent in either blood or brain or both. To further assess the mechanisms involved in astrocytic induction of MMP-9, we next examined primary mouse astrocyte cultures. Exposure to hemoglobin rapidly upregulated MMP-9 in conditioned media within 1 to 24 h. Hemoglobin-induced MMP-9 was reduced by the free radical scavenger U83836E. Taken together, these data suggest that although there are large amounts of MMP-9 in blood, hemoglobin-induced oxidative stress can trigger MMP-9 in astrocytes and these parenchymal sources of matrix degradation may also be an important factor in the pathogenesis of hemorrhagic brain edema. 相似文献
146.
Hongning Zhao Xiaoming Wang Junqiang Zhang Deben Yang Xiaoqiong Zhao Xin Liu Hui Huang Jianxiu Hu 《中国神经再生研究》2007,2(11):675-677
BACKGROUND: The examination of sympathetic skin response is an important index for assessing the autonomic nerve function, and patients with myasthenia gravis are always accompanied by dysautonomia. Therefore, it will be important to know whether sympathetic skin response can be used as the index for the clinical evaluation of myasthenia gravis.
OBJECTIVE: To investigate the diagnostic value of sympathetic skin response in the damage of autonomic nerve function of patients with myasthenia gravis.
DESIGN: A case-controlled comparative observation.
SETTING: Department of Neurology and Room of Nerve Electromyogram, the Affiliated Hospital of North Sichuan Medical College.
PARTICIPANTS: Thirty outpatients or inpatients with myasthenia gravis were selected from the Department of Neurology, the Affiliated Hospital of North Sichuan Medical College from May 2006 to May 2007, including 9 males and 21 females, aged 8–72 years with a mean age of (28±5) years old. They were all accorded with the diagnostic standards of myasthenia gravis, accompanied by different severity of autonomic nerve symptoms, including poor skin nutrition, sweating of hands and feet, pyknocardia, persistent hypotension, abdominal pain, constipation, etc. They all had not taken any drug affecting the autonomic nerve function before the examination. Informed consents were obtained from all the patients. Meanwhile, 30 healthy physical examinees were enrolled as the normal control group, including 10 males and 20 females, aged 10–75 years with a mean age of (31±5) years old. Approval was obtained from the hospital ethic committee.
METHODS: After admission, the patients were examined with sympathetic skin response using DANTEC keypoint 2.0 electromyography evoked potential apparatus (Danmark). The changes of the latency and wave amplitude of sympathetic skin response were observed. The subjects in the normal control group were examined with the same methods at physical examination. Abnormality was judged by the disappearance of wave form, latency longer than that in the normal control group by Mean±2.5SD, or wave amplitude lower than the average value in the normal control group by 50%.
MAIN OUTCOME MEASURES: The results of the latency and wave amplitude of sympathetic skin response were compared between the patients with myasthenia gravis and normal controls.
RESULTS: All the 30 patients with myasthenia gravis and 30 healthy physical examinees were involved in the final analysis of results. There were no significant differences between the left and right upper and lower limbs in both the myasthenia gravis group and normal control group (P > 0.05). In the myasthenia gravis group, the abnormal rate of sympathetic skin response was 37% (11/30), the latency was prolonged and the wave amplitude was decreased as compared with those in the normal control group, and there were significant differences (P < 0.01).
CONCLUSION: Sympathetic skin response can be used as an electrophysiological index for judging the damages of autonomic nerve function in patients with myasthenia gravis. 相似文献
147.
转化生长因子β对人颈椎关节突关节软骨细胞基质金属蛋白酶13基因表达的调节作用及意义 总被引:1,自引:1,他引:0
目的 探讨转化生长因子β(TGF-β)对人的颈椎关节突关节透明软骨细胞基质金属蛋白酶13(MMP-13)基因表达的作用,旨在阐明颈椎退行性变的相关发生机理。方法 应用逆转录方法PCR及实时荧光定量方法,检测不同浓度TGF-β作用传代培养人的透明软骨细胞MMP-13mRNA的含量。另外3种不同浓度分别与10ng/ml IL-1β组成联合作用组,共计6个实验组及1个正常对照组。结果 正常对照组中透明软骨细胞仅见MMP-13mRNA扩增产物,实验组TGF-β1、10和100ng/ml作用12h后,MMP-13mRNA表达逐渐增强;而联合作用组中,随着TGF-β1浓度的升高,MMP-13mRNA表达逐渐降低,并且各组之间存在明显的差异(P〈0.05)。结论 TGF-β可按剂量依赖方式调节颈椎关节突关节软骨细胞MMP-13mRNA的表达。 相似文献
148.
Diana Bell Yi-Jue Zhao Pulivarthi H. Rao Randal S. Weber Adel K. El-Naggar 《Head and neck pathology》2007,1(2):165-168
We present an adenoid cystic carcinoma of the base of tongue in a 48-year-old male with a restricted chromosomal alteration
by cytogenetic and spectral karyotypic analysis (SKY). SKY and G-banding analyses identified the t(6;14)(q25;q13) as the sole
structural aberration in all metaphases analyzed. This finding supports a critical role for this event in the development
of this tumor. The implications of chromosome 6q translocation in this case and in previously reported adenoid cystic carcinomas
are highlighted and discussed. 相似文献
149.
肠道T细胞淋巴瘤临床分析 总被引:1,自引:0,他引:1
本文总结报告了3例肠道T细胞淋巴瘤(intestinal T-cell lymphoma,ITCL)的诊治资料,并结合文献复习,发现IT—CL多见于中年男性,以腹痛、血便、发热、体质量下降为主要症状,治疗效果差,预后不良。病理改变以肠道溃疡形成为特点,溃疡形态呈多形性、多灶性、不规则,镜下瘤细胞明显异型、弥漫性浸润,中至大细胞多见。肿瘤细胞呈T细胞表型。ITCL临床少见,缺乏特异性临床表现,极易误诊。故临床医师应重视对ITCL临床病理特征、免疫表型和基因型的研究,注意识别,促其早期诊治。 相似文献
150.