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41.
Journal of Digital Imaging - Although medical imaging is frequently used to diagnose diseases, in complex diagnostic situations, specialists typically need to look at different modalities of image... 相似文献
42.
人原发性肝细胞癌核基质蛋白的研究 总被引:6,自引:2,他引:4
目的比较正常肝与原发性肝细胞癌(HCC)核基质蛋白的异同,观察是否有HCC特异性核基质蛋白的存在。方法用双向电泳方法比较了3例正常肝和8例HCC核基质蛋白成分。结果正常肝和HCC的核基质蛋白组成极为相似,但在HCC中发现至少有4个HCC的特异性核基质蛋白。其中以分子量为62000、等电点为5.3的蛋白最具代表性,它存在于所研究的8例HCC中。其余3个HCC特异性蛋白亦存在于大多数HCC中。3例正常肝组织中未见有这4个HCC特异性核基质蛋白。结论HCC确实有HCC特异性核基质蛋白的存在,它的发现可能会为HCC的发生、发展、发病机理的研究提供一个新途径。 相似文献
43.
Xu PT Schmechel D Qiu HL Herbstreith M Rothrock-Christian T Eyster M Roses AD Gilbert JR 《Neurobiology of disease》1999,6(1):63-75
Mice transgenic for human APOE2, E3, and E4 alleles express native 34-kDa human apoE and two sialylated apoE isoproteins with approximate molecular weights of 37 kDa (apoEs) and 39 kDa (apoEs2) in brain. These multiple apoE/apoEs/apoEs2 band patterns on Western blot are also observed in human brain, but are not seen in wild-type mouse brain. Both the 37-kDa apoEs and 39-kDa apoEs2 are coprecipitated with native 34-kDa apoE by antibody to human apoE. Neuraminidase digestion eliminates the 37- and 39-kDa forms and results in a downward shift in the bands to the position of the 34-kDa native form. These sialylated apoE isoproteins are found preferentially associated with neurons and contribute significantly (50-60%) to the total neuronal apoE in neuronal cultures from transgenic mice, while only 5-10% of total apoE is sialylated in cultures enriched in glial cells. In situ hybridization and immunocytochemistry demonstrate apoE mRNA and apoE immunoreactivity are predominantly located in cell soma of neurons, not in neuronal processes. 相似文献
44.
目的观察和研究敏感期内、末不同时限单眼斜视(monocularstrabismus,MS)和单眼剥夺(monoculardeprivation,MD)幼猫视皮质、外侧膝状体的脑源性神经营养因子(brainderivedneurotrophicfactor,BDNF)的可塑性变化。从形态学、分子神经生物学角度探讨不同时限MS和MD幼猫视 相似文献
45.
Evidence for an essential role of reactive oxygen species in the genesis of late preconditioning against myocardial stunning in conscious pigs. 总被引:13,自引:1,他引:12 下载免费PDF全文
J Z Sun X L Tang S W Park Y Qiu J F Turrens R Bolli 《The Journal of clinical investigation》1996,97(2):562-576
Conscious pigs underwent a sequence of 10 2-min coronary occlusions, each separated by 2 min of reperfusion, for three consecutive days (days 1, 2, and 3). On day 1, pigs received an i.v. infusion of a combination of antioxidants (superoxide dismutase, catalase, and N-2 mercaptopropionyl glycine; group II, n = 9), nisoldipine (group III, n = 6), or vehicle (group I [controls], n = 9). In the control group, systolic wall thickening (WTh) in the ischemic-reperfused region on day 1 remained significantly depressed for 4 h after the 10th reperfusion, indicating myocardial "stunning." On days 2 and 3, however, the recovery of WTh improved markedly, so that the total deficit of WTh decreased by 53% on day 2 and 56% on day 3 compared with day 1 (P < 0.01), indicating the development of a powerful cardioprotective response (late preconditioning against stunning). In the anti-oxidant-treated group, the total deficit of WTh on day 1 was 54% less than in the control group (P < 0.01). On day 2, the total deficit of WTh was 85% greater than that observed on day 1 and similar to that observed on day 1 in the control group. On day 3, the total deficit of WTh was 58% less than that noted on day 2 (P < 0.01). In the nisoldipine-treated group, the total deficit of WTh on day 1 was 53% less than that noted in controls (P < 0.01). On days 2 and 3, the total deficit of WTh was similar to the corresponding values in the control group. These results demonstrate that: (a) in the conscious pig, antioxidant therapy completely blocks the development of late preconditioning against stunning, indicating that the production of reactive oxygen species (ROS) on day 1 is the mechanism whereby ischemia induces the protective response observed on day 2; (b) antioxidant therapy markedly attenuates myocardial stunning on day 1, indicating that ROS play an important pathogenetic role in postischemic dysfunction in the porcine heart despite the lack of xanthine oxidase; (c) although the administration of a calcium-channel antagonist (nisoldipine) is as effective as antioxidant therapy in attenuating myocardial stunning on day 1, it has no effect on late preconditioning on day 2, indicating that the ability of antioxidants to block late preconditioning is not a nonspecific result of the mitigation of postischemic dysfunction on day 1. Generation of ROS during reperfusion is generally viewed as a deleterious process. Our finding that ROS contribute to the genesis of myocardial stunning but, at the same time, trigger the development of late preconditioning against stunning supports a complex pathophysiological paradigm, in which ROS play an immediate injurious role (as mediators of stunning) followed by a useful function (as mediators of subsequent preconditioning). 相似文献
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48.
目的:介绍枕下-颞下联合入路切除颞骨良性肿瘤的方法及体会。方法:对3例颞枕骨化纤维瘤、颞骨纤维异常增殖症、颞骨血管瘤的巨大颞骨良性肿瘤,均采用枕下-颞下联合入路(倒钩形切口)。辅以显微外科技术进行手术摘除肿瘤。结果:3例均基本完整切除肿瘤,无颅内外感染、脑脊液漏、迷路及颅神经损伤等并发症,经术后随访1.5年~2年未发现肿瘤复发。结论:采用枕下-颞下联合入路切除颞枕骨良性肿瘤可获理想的暴露,最大范围切除肿瘤,可避免损伤毗邻的颅神经、血管以及内耳结构,值得推广。 相似文献
49.
Nm23 protein expression was analyzed by immunohistochemical staining using formalin-fixed, paraffin-embedded sections from 39 cases with osteosarcomas and compared with the histologic findings and early metastasis for the purpose of detecting nm23 expression in osteosarcoma and elucidating the clinical significance of its expression. Immunoreactivity of nm23 protein was detected in 48.7% of the total cases. There was no statistical difference between nm23 expression and early metastasis, but there was a trend for cases with nm23 expression to progress to early metastasis within 1 year after operation. The role of nm23 as a tumor metastasis suppressor in osteosarcomas appeared less prominent. 相似文献
50.
静脉注射硝酸甘油诱导大鼠脑膜核因子-κB表达增强 总被引:4,自引:0,他引:4
目的观察偏头痛大鼠模型不同时相脑膜核因子-κB(NF-κB)的表达特征.方法采用静脉注射硝酸甘油(GTN)法建立大鼠偏头痛模型,应用免疫组织化学法观察对照组、GTN iv 后0.5,1.0, 1.5, 2.0, 4.0 h组脑膜NF-κB阳性染色细胞的分布,采用Western印迹法观察相应时间点脑膜核NF-κB的蛋白表达量.结果 GTN iv后0.5 h即出现大鼠脑膜NF-κB核阳性反应和核NF-κB蛋白表达量增高,1.5 h核NF-κB蛋白表达量达高峰,然后逐渐回落,至4 h接近正常水平.结论 GTN iv后早期脑膜呈时限性核NF-κB蛋白表达增强,提示NF-κB蛋白表达增强可能与偏头痛有关. 相似文献