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排序方式: 共有444条查询结果,搜索用时 15 毫秒
1.
Yasuhiko Tamada Hiromichi Takama Toshihiko Ikeya Takashi Yokochi Hijiri Mori Yoshinari Matsumoto 《The Journal of dermatology》1995,22(12):913-916
Lewis Y (Ley) antigen, a difucosylated tetrasaccharide found on type 2 blood group oligosaccharides of glycolipids and glycoproteins, is thought to be a phenotypic marker predictive of cell differentiation. The distribution of this antigen in human anagen hair follicles was examined by immunohistochemical staining using a monoclonal antibody (AH-6) to Ley. In the bulbar and suprabulbar portion of anagen hair follicles, Ley antigen was detected in the three layers of the inner root sheath. Subsequently, the positive staining became translocated to the innermost layer of the outer root sheath in the middle part of the hair follicles. In the upper portion of the hair follicles, Ley antigen was found in the outer cells of the outer root sheath. These findings suggested that the expression of Ley antigen in the anagen hair follicles was correlated with the processes of keratinization or terminal differentiation. 相似文献
2.
We report a case of ectopic ectodermal structures in the ectocervix of a 51-year-old female. Sebaceous glands and numerous abnormal hair follicles were present in the stroma of an otherwise normal cervix. 相似文献
3.
Polyovular follicles in the ovary of immature mice exposed prenatally to diethylstilbestrol 总被引:2,自引:0,他引:2
Summary Polyovular follicles (PF) occur in the ovary of 30-day-old offspring of ICR/JCL mice given 4 daily subcutaneous injections of 20–2,000 g diethylstilbestrol (DES)/day from days 15 to 18 of gestation. PF containing 2–9 oocytes per follicle in the prenatally DES-exposed mice are increased 33- to 112-fold as compared to controls. In 5- to 25-day-old offspring of mothers given injections of 2,000 g DES/day, PF are observed 17–65 times more frequent than in controls. 相似文献
4.
Chronic exposure to dibromoacetic acid, a water disinfection byproduct, diminishes primordial follicle populations in the rabbit. 总被引:1,自引:0,他引:1
K J Bodensteiner H R Sawyer C L Moeller C M Kane K-Y F Pau G R Klinefelter D N R Veeramachaneni 《Toxicological sciences》2004,80(1):83-91
To determine if dibromoacetic acid (DBA) affects ovarian folliculogenesis, four groups of female Dutch-belted rabbits were exposed daily to 0, 1, 5, or 50 mg DBA/kg body weight in drinking water beginning in utero from gestation day 15 throughout life. Functionality of the endocrine axis was assessed by measuring serum concentrations of gonadotropins following an im injection of 10 microg GnRH at 12 (prepubertal; n = 6/dose group) and 24 (postpubertal; n = 10/dose group) weeks of age. A day after GnRH challenge, number of ovulation sites and ovarian weights were determined at necropsy. Left ovaries were processed for histopathology, serially sectioned at 6 microm, and every twelfth section stained with hematoxylin and eosin was evaluated. All healthy follicles were categorized as primordial, primary, small preantral, large preantral, or small antral follicles. The area of each section evaluated was measured and the number of follicles in each category expressed per mm2 unit area. In prepubertal animals, DBA caused a reduction in number of primordial follicles (p < 0.05) and total healthy follicles (p < 0.05) at 50 mg/kg dose level. In adult animals, there were fewer primordial follicles in both the 5 (p < 0.01) and 50 (p = 0.1) mg/kg dose groups. No profound changes in gonadotropin profiles were observed. Although chronic exposure to DBA did not appear to have an effect on late follicular development or ovulation, DBA did reduce the population of primordial follicles. The long-term health consequences of diminished primordial follicles are unknown, but it is very likely that reproductive senescence would occur earlier. 相似文献
5.
哺乳动物卵巢中含有大量的窦前卵泡,如何开发和利用这一资源,获取大量成熟并具有受精能力的卵母细胞,已成为现今的研究热点。研究窦前卵泡的分离与体外培养不仅可以为女性提供生殖保险,还可以在细胞和分子水平研究卵母细胞的生长发育及凋亡机制,为建立人类卵子库提供实验依据。对相关研究结果进行综述。 相似文献
6.
目的:观察补体成分在淋巴组织中的表达,探讨不同发育阶段淋巴滤泡中补体激活与免疫球蛋白沉积及滤泡树突状细胞之间的关系。方法:采用免疫组化方法对淋巴组织标本进行IgG、IgM、IgA、C3c、C4c、C1q和C4d标记,同时对其部分标本进行双标染色。结果:淋巴组织次级滤泡的Ⅰ~Ⅳ期的生发中心才出现不同程度的IgG、IgM、IgA、C3c、C4c、C1q、C4d阳性表达;免疫球蛋白与补体成分重叠沉积,并呈不规则网线状包绕在滤泡树突状细胞周围。其中以C4d的阳性表达最强。结论:淋巴滤泡生发中心有大量免疫球蛋白和补体成分围绕滤泡树突状细胞沉积,可能与中心淋巴细胞的发育和选择有关。 相似文献
7.
I. Brüske-Hohlfeld H. Scherb M. Bauchinger E. Schmid H. Fender G. Wolf 《International journal of radiation biology》2013,89(1):111-116
Purpose : Between 1990 and 1991 a leukaemia cluster was observed in children living close to the combined site of a nuclear power plant and a nuclear research facility in Elbmarsch, a region in Lower Saxony (Germany). We aim to investigate the prevalence of presumably radiation-induced chromosomal aberrations in peripheral blood lymphocytes of children in Elbmarsch and children of a control region in order to find out whether there was an uncontrolled release of radioactive material which resulted in a substantial exposure. Materials and methods : The frequency of dicentric and ring chromosomes in lymphocytes of the peripheral blood in 42 children in Elbmarsch and 30 children in Plön was investigated. Children in both groups had been permanent residents of the study area. Results : The mean frequency of dicentric and ring chromosomes in Elbmarsch was 14/32580 cells (=0.430 ×10 -3 ; 95% CI 0.24-0.70 ×10 -3 cells), and in Plön it was 17/24065 cells (=0.706 ×10 -3 ; 95% CI 0.42-1.10 ×10 -3 cells). Conclusions : No difference in the frequency of dicentric and ring chromosomes was observed between children in Elbmarsch living close to a combined site of a nuclear power plant and a nuclear research facility and children living in the control area Plön. The power of the study to detect a threefold or higher increase in the aberration frequency was at least 0.86. 相似文献
8.
9.
Ultrastructural study of M cells from colonic lymphoid nodules obtained by colonoscopic biopsy 总被引:4,自引:0,他引:4
Dr. Yoshinori Fujimura MD Masayo Hosobe MD Tsuyoshi Kihara MD 《Digestive diseases and sciences》1992,37(7):1089-1098
The present study was undertaken to investigate ultrastructurally the epithelium covering lymphoid nodules obtained from colonoscopic biopsies of the human colon and rectum. Colonoscopy using the dye spraying contrast, method was performed in nine patients who showed x-ray evidence of lymphonodular hyperplasia. Fifty-two colonoscopical biopsy specimens, of lymphoid nodules were obtained from the ascending, transverse, and descending colon and rectosigmoid region. All specimens were observed by light and electron microscopy. Light microscopy disclosed large lymphoid follicles protruding into the lumen with a dome-type configuration. These extended to the lamina propria of the mucosa and were associated with a massive lymphoid aggregation extending as far as the muscularis mucosa from the submucosa. The epithelium covering these nodules contained a few goblet cells and many lymphocytes. Observation of the elevated surface at the apex by scanning electron microscopy revealed M cells with sparse microvilli in the dome epithelium surrounded by crypts. Transmission electron microscopy disclosed M cells enfolding many immature or mature lymphocytes and plasmocytes. The M cells had cytoplasmic microvilli (so-called microfolds) on their surfaces, well-developed tubulovesicular systems, and vacuoles in the cytoplasm. The basic structure of the M cells as observed by scanning and transmission electron microscopy was the same as that of M cells in the Peyer's patches of humans and mice. The apical surface of the colonic lymphoid follicles in Crohn's disease patients was associated with erosions observed by scanning electron microscopy. The erosions proved to be the naked surface of the dome after removal of the epithelium and many holes from 2.0 to 6.0 m in diameter were observed on the naked surface. At high magnification, lymphocytes were seen projecting from holes (18%) on the naked surface of the dome. These ultrastructural findings indicate that human colonic lymphoid follicles are very similar to those seen in other species. 相似文献
10.