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排序方式: 共有212条查询结果,搜索用时 15 毫秒
1.
Melanoses of the gastrointestinal tract   总被引:4,自引:0,他引:4  
Electronmicroscopy and electron probe energy dispersive X-ray analysis studies have substantially contributed to our understanding of the various gastrointestinal tract melanoses. The nature of the pigment granules which occur in the various melanoses is discussed; their pattern of distribution in melanosis coli, melanosis ilei, melanosis duodeni and melanosis oesophagi is summarized and current knowledge of the aetiology and pathogenesis of these conditions is reviewed. Brief mention is also made of other examples of lipofuscin pigmentation, and a case of haemosiderosis ilei is described.  相似文献   
2.
The aging brain     
A recent interest in aging of the nervous system is related to the remarkable increase in the numbers of elderly persons throughout the world. As a reflection of the added years, pathologies in the older person have also increased. Primary among those which affect the activities and behavior of these people are the dementias, especially Alzheimer's Disease. To focus on such problems, however, requires an understanding of the changes which take place in the normal aging nervous system. This paper reviews some of the accepted criteria for these changes as well as the possible attempts by the nervous system to alter its structure in response to these changes.  相似文献   
3.
The Hermansky-Pudlak Syndrome, a tyrosinase positive form of oculocutaneous albinism, is a triad comprising albinism, a hemorrhagic diathesis and ceroid-lipofuscin storage. A pedigree is presented showing consanguinity with a pattern of pseudodominance.Electroretinography in two isolated Hermansky-Pudlak subjects was distinctly abnormal, showing decreased rod and cone responses (as well as abnormal flicker fusion responses) in one patient, and reduced photopic and scotopic responses in another. The decreased ERG responses are discussed with reference to the known retinal abnormalities in both generalized oculocutaneous albinism and Batten's disease, another ceroidlipofuscin storage disorder.  相似文献   
4.
 目的,探讨葛根素注射液对慢性乙醇中毒小鼠记忆障碍的改善作用及其脑内机制。方法每日给予30%乙醇连续4周造成小鼠慢性乙醇中毒,同时每日ip 20,100 mg·kg-1葛根素注射液治疗4周,用Y-迷宫检测小鼠分辨学习和记忆行为的变化,用紫外分光光度计和荧光分光光度计分别检测脑组织SOD,脂褐素生化指标;用电镜和计算机图像分析仪观测小鼠海马CA3区Gray Ⅰ型突触界面结构参数的变化。结果葛根素注射液100 mg·kg-1可显著改善长期给予乙醇造成的小鼠学习记忆功能障碍;显著提高脑组织SOD的活性,使小鼠脑内脂褐素含量明显下降;同时使海马突触后致密物质(PSD)厚度显著增加,突触间隙宽度显著减小。结论葛根素注射液能改善慢性乙醇中毒引起的小鼠学习记忆功能障碍,该作用可能与其提高脑组织抗氧化能力,改变海马突触界面结构有关。  相似文献   
5.
Neurone damage and eventual loss may underlie the clinical signs of disease in the transmissible spongiform encephalopathies (TSEs). Although neurone death appears to be through apoptosis, the trigger for this form of cell death in the TSEs is not known. Using two different murine scrapie models, hippocampal pyramidal cells were studied through microinjection of fluorescent dye, and synaptic integrity, using p38-immunoreactivity (p38-IR), both visualized using confocal laser scanning microscopy. Intradendritic distensions and dendritic spine loss were found to co-localize to areas of vacuolar and prion protein pathology in the hippocampus of mice infected with ME7 or 87 V scrapie. A significant reduction in p38-IR was found concomitantly in the hippocampus in ME7 scrapie mice. These results indicate that both pre- and post-synaptic sites are altered by scrapie infection; this would disrupt neuronal circuitry and may initiate apoptotic cell death, giving rise to the neurological disturbances manifested in clinical TSE cases.  相似文献   
6.
补肾填精方具有降低老龄鼠脑细胞脂褐素的含量,改善外周血SOD、LPO浓度的作用,有一定的延缓衰老的作用。  相似文献   
7.
淫羊藿有效成分抗氧化作用研究   总被引:40,自引:1,他引:40  
实验结果发现巫山淫羊藿多糖多相脂质体(ESPS)能明显提高老龄动物红细胞及肝组织中SOD的活性,提高老龄小鼠红细胞GSH-Px的活性;能明显降低老龄动物血清及肝组织中LPO的含量,降低老龄小鼠心肌脂褐质的含量。  相似文献   
8.
Phosphoinositide (PI) lipids are intracellular membrane signaling intermediates and effectors produced by localized PI kinase and phosphatase activities. Although many signaling roles of PI kinases have been identified in cultured cell lines, transgenic animal studies have produced unexpected insight into the in vivo functions of specific PI 3- and 5-kinases, but no mammalian PI 4-kinase (PI4K) knockout has previously been reported. Prior studies using cultured cells implicated the PI4K2α isozyme in diverse functions, including receptor signaling, ion channel regulation, endosomal trafficking, and regulated secretion. We now show that despite these important functions, mice lacking PI4K2α kinase activity initially appear normal. However, adult Pi4k2aGT/GT animals develop a progressive neurological disease characterized by tremor, limb weakness, urinary incontinence, and premature mortality. Histological analysis of aged Pi4k2aGT/GT animals revealed lipofuscin-like deposition and gliosis in the cerebellum, and loss of Purkinje cells. Peripheral nerves are essentially normal, but massive axonal degeneration was found in the spinal cord in both ascending and descending tracts. These results reveal a previously undescribed role for aberrant PI signaling in neurological disease that resembles autosomal recessive hereditary spastic paraplegia.  相似文献   
9.
目的:研究急性和慢性特发性中心性浆液性脉络膜视网膜病变眼底自发荧光影像模式及眼底荧光血管造影相关性发现。

方法:观察性研究案例。回顾性分析中心性浆液性脉络膜视网膜病变患者临床数据,眼底荧光血管造影及眼底自发荧光影像,并对其调查结果进行比较。

结果:该研究共纳入17例25眼。确诊为急性中心性浆液性脉络膜视网膜病变5眼,慢性疾病或复发性慢性疾病20眼。急性病例眼底自发荧光影像显示低荧光点与荧光血管造影检测出的荧光渗漏点位置相同。慢性特发性中心性浆液性脉络膜视网膜病变眼底荧光血管造影为视网膜色素上皮弥漫性萎缩区域,可透视荧光。眼底自发荧光影像的低荧光区域的形态和位置与眼底荧光血管造影的高荧光区域相对应,然而眼底荧光血管造影的低荧光区域与眼底自发荧光影像的高荧光区域相对应。在急性病例中,低自发荧光点不能准确指出视网膜色素上皮的渗漏点。

结论:中心性浆液性脉络膜视网膜病变眼底自发荧光影像模式能够描述疾病不同阶段的特征,具有无风险和可再生性,可替代荧光素血管造影术治疗中心性浆液性脉络膜视网膜病变。  相似文献   

10.
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