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51.
目的探讨高血压视网膜病变的发病机制及卡托普利防治高血压视网膜病的治疗机制. 方法 应用光镜定量酶组织化学方法对正常京都种大鼠(正常组),自发性高血压大鼠(高血压组)和卡托普利终身用药治疗的自发性高血压大鼠(用药组)的视网膜组织的Ca2+-ATP酶的分布和活性进行定量观察. 结果 Ca2+-ATP酶在正常组大鼠视网膜组织中主要分布在杆锥细胞层内节、外核层和节细胞神经纤维层,上述三层Ca2+-ATP酶活性(U/μm2)分别为0.662±0.014, 0.665±0.018和0.525±0.021,在高血压组大鼠视网膜组织中,各层Ca2+-ATP酶活性下降,三层Ca2+-ATP酶活性分别为0.610±0.017, 0.598±0.014和0.481±0.010;在用药组大鼠视网膜组织中,Ca2+-ATP酶活性较高血压组增强,三层Ca2+-ATP酶活性分别为0.650±0.016, 0.650±0.014, 0.519±0.022.结论 Ca2+-ATP酶活性下降,细胞内液Ca2+浓度增加是高血压视网膜病变的原因之一;卡托普利防治高血压视网膜病的机制与增强Ca2+-ATP酶和降低细胞内Ca2+浓度有关. 相似文献
52.
大鼠第三脑室一氧化氮合酶阳性触液神经元的观察 总被引:1,自引:0,他引:1
应用NADPH-d组织化学方法研究脑室系统的一氧化氮合酶(NOS)阳性触液神经元。结果发现,NOS阳性触液神经元主要见于第三脑室。根据胞体所在位置,第三脑室NOS阳性触液神经元可有3种形式:(1)室管膜内触液神经元;(2)室管膜下或远位触液神经元,其突起伸入第三脑室室管膜上皮之间,这些NOS阳性触液神经元有的来自室旁核或室周核;(3)室管膜上触液神经元,其胞体位于室管膜表面。本文首次报道了第三脑室NOS阳性触液神经元,这种触液神经元的分布类型基本和其他递质触液神经元相类同,并讨论了NOS阳性触液神经元的功能。 相似文献
53.
《Acta odontologica Scandinavica》2013,71(4):269-300
This study was carried out in order to observe the changes in amino-peptidase activity which might occur in the palatal mucosa and gingiva of the rat in the initial phase of healing after tooth extractions. The material consisted of 115 male Sprague-Dawley rats. Amino-peptidase activity was studied at time intervals of 30 min., 1, 2, 4, 8, 16 hours and 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10 days after the extractions. The azocoupling principle was used for the histochemical demonstration of enzyme activity. However, the incubation solution was in gel form. A semipermeable membrane was placed between the tissue sections and the incubation medium in order to prevent enzyme diffusion and dissolving of enzymes into the incubation medium. The substrates used were N-aminoacyl 2-naphthylamines of L-leucine and L-arginine. Histological investigations were carried out simultaneously with the histochemical study. The principal increase in aminopeptidase activity occurred relatively late after the tooth extractions. The most intense staining was observed in 4- to 7-day wounds. During the same period the most active fibroblastic proliferation was observed histologically. The changes were demonstrable using both of the substrates. However, the staining was more intense when N-L-leucyl-2-naphthylamine was used as the substrate. By using N-L-arginyl-2-naphthylamine as the substrate, chloride ions caused a marked increase in staining intensity. It was thus assumed that aminopeptidase B would also be activated during the healing. 相似文献
54.
Mukaisho K Kurumi Y Sugihara H Naka S Kamitani S Tsubosa Y Moritani S Endo Y Hanasawa K Morikawa S Inubushi T Hattori T Tani T 《Digestive diseases and sciences》2002,47(11):2441-2445
We report on a case of metastatic adenocarcinoma of liver that was removed and examined histochemically after microwave coagulation therapy (MCT). The patient was a 65-year-old woman who had a metastatic tumor in the liver (S3) after high anterior resection due to a rectal adenocarcinoma and received MCT against the tumor. One month after MCT, multiple metastatic tumors were detected by abdominal computed tomography (CT) scan. As it was difficult to control them by MCT alone, we performed lateral segmentectomy. To assess the effects of microwave ablation on cellular viability of metastatic tumor, we used enzyme histochemistry for acid phosphatase (AcP), which is positive in macrophages infiltrating in the tumor. In a part of the ablated area of resected liver, there was remaining neoplastic tissue of which the morphology was maintained in H&E staining. This was found to be microwave-fixed non-viable tissue because no enzyme activity of AcP was detected in the infiltrating macrophages. This case report suggests that enzyme histochemistry was useful to assess the effect of MCT, enabling us to distinguish fixed cells from viable cells. 相似文献
55.
J. Garcia-Armengol Ph.D. J. Hinojosa Ph.D. S. Lledo Ph.D. J. V. Roig Ph.D. E. Garcia-Granero Ph.D. B. Martinez M.D. 《Diseases of the colon and rectum》1998,41(7):846-853
PURPOSE: This study was undertaken to investigate the morphologic and functional changes with time in the mucosa of the ileoanal pouch. METHODS: A morphologic study by histopathologic analysis, mucosal morphometry, and mucin histochemistry and a functional study by analysis of transmucosal potential difference were performed in 27 patients with an ileoanal J-pouch after restorative proctocolectomy for ulcerative colitis. In 19 patients with a normal ileoanal pouch, two prospective follow-up analyses were performed after median functional pouch times of 14 and 39 months. We also evaluated eight patients with the diagnosis of pouchitis (median follow-up, 52.5 months). RESULTS: In the normal ileoanal pouch group, some degree of chronic and acute inflammatory infiltration was identified in 100 percent and 63.2 percent of cases, respectively, with no significant differences being observed between the two follow-up analyses. The mean villous atrophy index at the first and second follow-up was 0.54 and 0.52, respectively, significantly lower (P<0.001; an indication of a greater degree of villous atrophy) than the value obtained from the control group with a healthy terminal ileum (0.77). The group of patients with pouchitis exhibited statistically significant differences in the degree of acute and chronic inflammatory infiltration, the extent of ulceration, the crypt depth, and the villous atrophy index, compared with patients without pouchitis. In the normal ileoanal pouch group, the median percentage of sulfomucin with each degree of atrophy (1=mild; 2=moderate; and 3=severe) was 2.6, 4.5, and 20.9 percent, respectively. In patients with pouchitis, the median percentage of sulfomucin was 5.9 percent. The mean transmucosal potential difference at the first follow-up (–25.3 mV) was significantly lower (P=0.001) than at the second (–30.4 mV). Significant differences were apparent with respect to both the normal ileum (–8.9 mV) and the normal rectum (–40.2 mV). CONCLUSION: These results suggest that the ileal pouch behaves as a neorectum, with different degrees of colonic metaplasia from a morphologic and a functional perspective.Read at the meeting of The American Society of Colon and Rectal Surgeons, Philadelphia, Pennsylvania, June 22 to 26, 1997. Dr. Garcia-Granero is an International Scholarship recipient. 相似文献
56.
Microscopic observation of chemical modification in sections using scanning acoustic microscopy
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Katsutoshi Miura Yuki Egawa Toshiaki Moriki Hiroyuki Mineta Hidekazu Harada Satoshi Baba Seiji Yamamoto 《Pathology international》2015,65(7):355-366
A scanning acoustic microscope (SAM) calculates the speed of sound (SOS) through tissues and plots the data on the screen to form images. Hard tissues result in greater SOS; based on these differences in tissue properties regarding SOS, SAM can provide data on tissue elasticity. The present study evaluated whether tissue modifications, such as formalin fixation, periodic acid‐Schiff (PAS) reactions and protein degradation, changed the acoustic properties of the tissues and whether SAM could be a useful tool for following chemical changes in sections. The fixation process was observable by the increased SOS. During the PAS reaction, the glycosylation of tissues was characterized by an increased SOS. Mucous or glycogen distribution was visualized and was found to be statistically comparable among lesions and states. Protease digestion by pepsin led to a decreased SOS. Tissue sensitivity to proteases varied due to the stage, cause and duration of inflammation or ageing. Changes in acoustic properties were more sensitive than those in optical histology. SAM facilitates the visualisation of the time course or distribution of chemical modifications in tissue sections, thus aiding their comparison among tissues. SAM may be an effective tool for studying changes such as protein cross‐linkage, tissue repair and ageing. 相似文献
57.
《Ultrastructural pathology》2013,37(3):411-418
Histochemical and ultrastructural studies were carried out in four gastric carcinoids, two of which were associated with atrophic gastritis and pernicious anemia. All tumors showed intense argyrophilia and vesicular granules resembling those of endocrine enterochromaffinlike (ECL) cells in normal human gastric mucosa. Tumor cells were found to be unreactive to all the 18 available antiserums to gut hormones, including gastrin, somatostatin, glucagon, and pancreatic polypeptide. The tumors were interpreted as ECL cell argyrophil carcinoids with various degrees of differentiation and atypia. 相似文献
58.
《Ultrastructural pathology》2013,37(5):366-372
AbstractThe GlcNAc-1-phosphotransferase catalyzes the first step in the formation of mannose 6-phosphate (M6P) residues on lysosomal acid hydrolases that is essential for the efficient transport of newly synthesized lysosomal enzymes to lysosomes and the maintenance of lysosomal functions. Mutations in the GlcNAc-1-phosphotransferase cause the lysosomal storage disease mucolipidosis type II (MLII), resulting in mistargeting and hypersecretion of multiple lysosomal hydrolases and subsequent lysosomal accumulation of nondegraded material in several tissues. To describe cell-type specificity, compositional differences, and subcellular distribution of the stored material we performed an in-depth ultrastructural analysis of lysosomal storage in brain and retina of MLII knock-in mice using electron microscopy. Massive vacuoles filled with heterogeneous storage material have been found in the soma, swollen axons, and dendrites of Purkinje, and granular cells in 9-month-old MLII mice. In addition, non-neuronal cells, such as microglial, astroglial, and endothelial cells, exhibit storage material. Fucose-specific lectin histochemistry demonstrated the accumulation of fucose-containing oligosaccharides, indicating that targeting of the lysosomal α-fucosidase is strongly impaired in all cerebellar cell types. The data suggest that the accumulation of storage material might affect neuronal function and survival in a direct cell-autonomous manner, as well as indirectly by disturbed metabolic homeostasis between glial and neuronal cells or by cerebrovascular complications. 相似文献
59.
《Connective tissue research》2013,54(3-4):319-331
Confluent bovine fetal tendon fibroblasts maintained in a chemically defined medium incorporated L-[6-3H]fucose and L-[5-3H]proline in a linear manner into non-diffusible macromolecules for up to 48 hrs. Equilibrium CsCl density gradient centrifugation indicated that [3H]fucose-labelled macromolecules released into the medium were predominantly glycoproteins. The [3H]fucose-labelled glycoproteins in the culture medium were analyzed by sodium dodecyl sulfate/polyacrylamide gel electrophoresis. This technique demonstrated the presence of a number of high mol. wt. fucosylated components, the most notable of which was a glycoprotein of apparent mol. wt. 150,000. Immunological procedures allowed the tentative identification of four glycoproteins including fibronectin which was found in the cell medium and in extracts of the cell layer. Two of the glycoproteins (mol. wts. 150,000 and 270,000) released into the incubation medium were shown to be related to the microfibrillar components of elastic tissue. One or more of the newly synthesized [3H]fucose labelled molecules was shown to be immunologically related to a glycoprotein (mol. wt. 60,000) extracted from bovine Achilles tendon. These studies represent the first demonstration of the synthesis of microfibril-related and tendon glycoprotein-related macromolecules by tendon fibroblasts in culture. 相似文献
60.