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排序方式: 共有1410条查询结果,搜索用时 15 毫秒
1.
Fibroblastic connective tissue nevus (FCTN) is a benign cutaneous mesenchymal lesion characterized by proliferation of CD34‐positive fibroblastic/myofibroblastic spindle‐shaped cells. We report a case of agminated FCTN on the right lower abdomen of a 1‐year‐old boy.  相似文献   
2.
Abstract  Gastrointestinal stromal tumor (GIST) is a recently described mesenchymal tumor that can develop in any portion of the gastrointestinal tract. The occurrence of a GIST in the urinary tract is rare, but GIST can present as tumor of the urinary tract or invade the urinary tract. This is the first reported case of GIST in the ileal neobladder, which presented as a submucosal tumor. The patient underwent an open exploration and partial resection of the neobladder pouch.  相似文献   
3.
Summary This study was undertaken to elucidate, using the Golgi method, the neuropathological change in the brain of the macular mutant mouse, whose hemizygote (Ml/y) is considered to be a model of Menkes kinky hair disease (MKHD). The hemizygote mice gradually lost weight after 10 days of age and died with emaciation and seizure around day 15. The normal littermate (+/y) was well developed. In the cerebrum, the arborization of pyramidal neurons in the layer V of the Ml/y was the same as that in the +/y on day 10. However, development of arborization in the Ml/y was delayed in comparison with that in the +/y on days 12 and 14. Purkinje cells with several somal sprouts were observed in the cerebellum in both the Ml/y and +/y on day 7. The somal sprouts in the +/y had regressed gradually by day 12, while they were still in the anterior and middle lobes of the Ml/y on day 14. Additionally, the trunks of Ml/y stem dendrites became thicker and a cactus formation was recognized on the branching portion of the dendrites on day 14. Arborization of these abnormal Purkinje cells was distinctly poor compared with that in the +/y. These results suggest that the growth of the neurons is delayed in the Ml/y and simultaneously their cytoskeletal developments are disturbed, especially in the Purkinje cells. There is a close similarity in many respects to the neuropathological change in MKHD.  相似文献   
4.
In order to examine time trends of the prevalences of HBeAg positives among HBV carriers in Japan, we analysed data on HBeAg of HBsAg positive voluntary blood donors (23,560 males, and 8659 females) at the Osaka Red Cross Blood Centre between January 1977 and March 1984. Age-specific prevalences of HBeAg positives decreased year by year for both sexes, especially for those in their teens and twenties. The prevalences of HBeAg positives decreased with age, but at any given age it was lower for the later than for the earlier birth cohorts. Although reasons for the secular declines are unknown, the findings suggest that the prevalence of HBeAg positives among HBV carriers will continue to decrease in Japan. This, together with the immunization programme implemented this year, may lead to a future reduction in the risk of HBV related liver diseases in Japan.  相似文献   
5.
M Yamano  M Tohyama 《Brain research》1987,408(1-2):22-30
We studied the afferent source of L-enkephalin-like immunoreactive (L-ENKLI) fibers in the ventral tegmental nucleus (VT) of Gudden, and efferent and afferent connections of L-ENKLI structures in the dorsal part of the dorsal tegmental nucleus (DDT) of Gudden in the rat, using immunocytochemistry combined with knife-cut and lesion experiments. The VT had a dense plexus of L-ENKLI fibers but no L-ENKLI cells. Destruction of the dorsal premammillary nucleus and medial mammillary nucleus pars medialis, which contained a large group of L-ENKLI neurons, markedly reduced L-ENKLI fibers in the ipsilateral VT, suggesting that most of these fibers originate in these nuclei. The DDT contained a large collection of L-ENKLI neurons together with dense L-ENKLI fibers. Destruction of the DDT caused a contralateral marked reduction of L-ENKLI fibers in the dorsolateral part of the interpeduncular nucleus (DL), suggesting that L-ENKLI neurons in the DDT project contralaterally to the DL. L-ENKLI fibers in the DDT may be of intrinsic origin.  相似文献   
6.
Summary A case of hemodialysis-associated amyloidosis in a patient who had been on hemodialysis for 10 years is described. Bone lesions were found in the humeral heads, carpal bones, and femoral heads and necks. Specimens obtained from the pathologically fractured left femoral neck revealed amyloid deposits histologically. Immunoperoxidase staining for beta-2 microglobulin was positive in the amyloid at the light-microscopic level. We reconfirmed that bone lesions associated with long-term hemodialysis are manifestations of amyloidosis of beta-2 microglobulin origin. Hemodialysis-associated amyloidosis should be considered in the treatment of long-term hemodialysis patients.  相似文献   
7.
To clarify the mechanism of postischaemic delayed cornu Ammonis (CA)-1 neuronal death, we studied correlations among calpain activation and its subcellular localization, the immunoreactivity of phosphatidylinositol 4,5-bisphosphate (PIP2) and Ca2+ mobilization in the monkey hippocampus by two independent experimental approaches: in vivo transient brain ischaemia and in vitro hypoxia-hypoglycaemia of hippocampal acute slices. The CA-1 sector undergoing 20 min of ischaemia in vivo showed microscopically a small number of neuronal deaths on day 1 and almost global neuronal loss on day 5 after ischaemia. Immediately after ischaemia, CA-1 neurons ultrastructurally showed vacuolation and/or disruption of the lysosomes. Western blotting using antibodies against inactivated or activated μ-calpain demonstrated μ-calpain activation specifically in the CA-1 sector immediately after ischaemia. This finding was confirmed in the perikarya of CA-1 neurons by immunohistochemistry. CA-1 neurons on day 1 showed sustained activation of μ-calpain, and increased immunostaining for inactivated and activated forms of μ- and m-calpains and for PIP2. Activated μ-calpain and PIP2 were found to be localized at the vacuolated lysosomal membrane or endoplasmic reticulum and mitochondrial membrane respectively, by immunoelectron microscopy. Calcium imaging data using hippocampal acute slices showed that hypoxia-hypoglycaemia in vitro provoked intense Ca2+ mobilization with increased PIP2 immunostaining specifically in CA-1 neurons. These data suggest that transient brain ischaemia increases intracellular Ca2+ and PIP2 breakdown, which will activate calpain proteolytic activity. Therefore, we suggest that activated calpain at the lysosomal membrane, with the possible release of biodegrading enzyme, will cause postischaemic CA-1 neuronal death.  相似文献   
8.
The influence of co-solvents on the in-vitro percutaneous penetration of indomethacin from gel systems was studied using a simplex lattice experimental design. Gel formulations were prepared by gelling the vehicle mixture of water, either alcohol or isopropanol and either propylene glycol or PEG 400 with 1% w/w Carbomer 940. Hairless mouse skin was employed as the barrier in a Franz-type diffusion cell. The penetration rates at steady state for seven formulations were fitted to a polynomial equation based on this simple lattice method and a three-dimensional plot was constructed. The formulation having the maximal penetration rate was determined to be the vehicle with a solvent ratio of water: alcohol: propylene glycol equal to 15:33:52, and which possessed a solubility parameter of 15 and a drug solubility of around 10 mg mL?1. When the solubility parameter of the vehicle was > 15, the drug solubility increased. However, the penetration rate decreased with an increasing solubility parameter. For those vehicles with a solubility parameter < 15, both the drug solubility and the penetration rate decreased with a decrease in the solubility parameter. There was shown to be an approximately 20-fold increase in the relative enhancement factor when using both alcohol and isopropanol, but only a threefold increase for both propylene glycol and PEG 400, when compared with water.  相似文献   
9.
The cerebellar Purkinje cells in the hemizygote of the macular mutant mouse contain numerous abnormal mitochondria which show a marked decrease in cytochrome c oxidase activity. Using histochemical methods we studied the activity of other mitochondrial enzymes, such as NADH diaphorase and succinic dehydrogenase, in the cerebellar cortex of this mutant mouse. Such activities were markedly increased in the Purkinje cells, especially in the soma and stem dendrite, from 10 days after birth in the hemizygote as compared with findings in normal littermates. These results were considered to be due to an increased number of abnormal mitochondria.Supported by the Research Grants nos. 2A-5-03 and 3B-1-04 for Nervous and Mental Disorders from the Ministry of Health and Welfare, and by Grant no. 04670492 of the Ministry of Education of Japanese Government  相似文献   
10.
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