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41.
人脑外伤后皮层核因子-κB的表达 总被引:5,自引:0,他引:5
目的 探讨核因子-κB(nuclear factor—κB,NF—κB)在人创伤性脑损伤(traumatic brain injury,TBI)后挫伤皮层中的表达情况,包括表达位置、表达强度和表达时相。方法 挫伤区皮层的标本来自24例TBI患者,取样时间为伤后5h-5d,利用凝胶电泳迁移分析法(electrophoretic mobility shift assay,EMSA)和免疫组化技术测定NF—κB的活性和表达强度。结果 在人TBI后的挫伤区皮层中,NF—κB表达明显上调,表达高峰为伤后48—72h,NF—κBP65主要在血管内皮细胞和神经胶质细胞中表达,NF—κBP50主要在神经胶质细胞和少量神经元中表达,NF—κBP65的表达强度高于NF—κBP50。结论 NF—κB在人TBI后的挫伤区皮层中表达上调,提示其可能在TBI后的病理生理过程中起着重要作用。 相似文献
42.
Q. Peng J. Moan Jahn M. Nesland Jan F. Evensen M. Kongshaug C. Rimington 《Lasers in medical science》1990,5(4):399-409
Observations on time-dependent localization of tetra(3-hydroxyphenyl)porphin (3-THPP) in human malignant melanoma transplanted to athymic nude mice from 1 to 120 h after intraperitoneal (i.p.) 10 mg kg–1 b.w. administration were made by means of fluorescence microscopy. Fluorescence was found on the membrane of the melanoma cells and in the cytoplasm with a peak fluorescence intensity at 24 h post-injection of 3-THPP. The growth of the tumour cells was obviously inhibited at an early stage after PCT. Morphological changes of the tumour at various intervals after treatment by PCT with 3-THPP were also observed. Diffuse degeneration of the tumour cells with swelling of mitochondria and endoplasmic reticulum, heterochromatin aggregation and margination, etc., and subsequently diffuse necrosis with little or no the background of tumorous vascular response were found at an early stage after PCT. On the other hand, it was also observed that the necrosis of the melanoma areas was caused as a consequence of tumorous vascular injury at a later stage after PCT. Thus, two tumoricidal processes caused by PCT with 3-THPP were seen: a direct phototoxic action on tumour cells at an early stage after PCT and an indirect effect secondary to tumorous vascular injury at a later period after PCT. 相似文献
43.
Jean-Marie Danion Marie-Agathe Zimmermann Dominique Willard-Schroeder Danielle Grangé Marie Welsch Jean-Louis Imbs Léonard Singer 《Psychopharmacology》1990,102(3):422-424
The effects of scopolamine, an anticholinergic drug, of trimipramine, a tricyclic antidepressant with both anticholinergic and sedative properties, of diazepam and a placebo, on explicit memory and repetition priming were assessed using a free-recall task and a word-stem completion task. Forty-eight healthy volunteers took part in this double-blind study. Diazepam provoked a dissociation between free recall, which was profoundly impaired, and word completion, which was spared. No significant changes in memory performances were observed in the scopolamine group; however, a significant correlation between explicit and implicit memory performances was observed in this group. At the low dose used, the effects of trimipramine on memory were mild. The results suggest that the cholinergic system is involved in the priming effect. 相似文献
44.
Tape stripping of human stratum corneum yields cell layers that originate from various depths because of furrows in the skin 总被引:2,自引:0,他引:2
R. G. van der Molen F. Spies J. M. van ‘t Noordende E. Boelsma A. M. Mommaas H. K. Koerten 《Archives of dermatological research》1997,289(9):514-518
Received: 21 November 1996 相似文献
45.
d-宁烯、丹参及姜黄素衍生物对ras基因产物膜结合和细胞间隙信息传导的影响 总被引:3,自引:0,他引:3
目的旨在寻找新型抗肿瘤药物,进一步研究d-宁烯、丹参及姜黄素衍生物的抗肿瘤机理。采用分子生物学方法及划痕标记染料示踪技术,研究了4种人实体瘤起源的细胞系的细胞间隙信息传导(GJIC)、H-ras癌基因表达以及ras癌基因产物(P21ras蛋白)表达状态,并观察了4种天然产物对它们的影响。结果表明,细胞内染料传输功能的丧失与ras基因突变率呈正相关;单萜化合物d-宁烯和酚类化合物丹参衍生物的抗肿瘤作用可能与抑制P21ras蛋白膜结合和增强细胞间隙信息传导功能有关。提示Ras癌基因产物P21ras蛋白膜结合的抑制与细胞间隙信息传导功能的增强有直接关系。 相似文献
46.
Z. Lackovi M. Jakup
evi A. Bunarevi I. Damjanov M. Relja I. Kostovi 《Brain research》1988,443(1-2):199-203
The content of serotonin (5-HT), 5-hydroxyindoleacetic acid (5-HIAA) and norepinephrine (NE) was analysed in 71 human spinal cords obtained post-mortem. The highest content of 5-HT, 5-HIAA and NE was found in the lumbar enlargement of the spinal cord. 5-HT and 5-HIAA content increased from fetal to adult spinal cord whereas the content of NE decreased. Characteristic segmental distribution of measured monoamines was present in adult spinal cord only. In two patients spinal cord lesion led to the reduction in spinal cord content of 5-HT, 5-HIAA and NE and loss of characteristic segmental distribution of these substances. These results are in general agreement with observations on spinal cord of different animal species. 相似文献
47.
48.
凋亡相关基因突变与人类疾病 总被引:4,自引:2,他引:2
细胞凋亡 (又称细胞程序性死亡 )过程由多种不同基因产物的协同作用来完成。其中某些凋亡基因的突变 ,已被认定为人类疾病的病因或相关因素。作者综述了当前对凋亡基因突变所致人类疾病的认识 ,以及将凋亡的基础研究成果应用到临床疾病诊治的情况 相似文献
49.
We correlated MRI features with histopathological findings in an HIV-positive patient with vacuolar myelopathy. On MRI symmetrical
nonenhancing high-signal areas in the posterior columns on T2-weighted images result from extensive vacuolation visible on
histological sections.
Received: 18 November 1997 Accepted: 23 March 1997 相似文献
50.
人乳头瘤病毒感染的多灶性的临床分析 总被引:10,自引:0,他引:10
对176例外阴尖锐湿疣患者的子宫颈进行检测,以诊断是否同时伴有人乳头状瘤病毒(HPV)感染。结果:肉眼观察诊断宫颈HPV感染23例(13%),阴道镜诊断146例(83%),宫颈活检病理诊断112例(64%),其中合并宫颈上皮内瘤变(CIN)1 ̄2级32例(18%)。结果提示:(1)外阴尖锐湿疣患者子宫颈伴有HPV感染和/或亚临床感染相当常见。(2)借助阴道镜取宫颈活检是诊断宫颈HPV感染的常用方法 相似文献