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81.
82.
Xiaoyan Tang Sadaaki Hori R. Yoshiyuki Osamura Yutaka Tsutsumi 《Pathology international》1995,45(1):34-44
Extensive immunohistochemical analyses of the hyperplastic human palatine tonsil disclosed variegated B cell phenotypes on the lymphoid cells among the crypt epithelium. The reticular epithelial network was evident by cytokeratin immunostaining. The reticular epithelium near the crypt Iumen was positive for Iysozyme. Secretory component was negative, while HLA-DR was frequently expressed. Intramucosal small Iymphocytes, densely distributed in the Iuminal side, consisted mainly of B cells expressing CD19, CD20, CD21, CD22, CD45R, CD74, DBB42, HLA-DR, HLA-DQ, bcl-2 protein and surface lgM. Some B cells revealed mantle zone phenotypes (surface IgD+, CD5+, CD24+, DBA44+, CD10- -, DNA7- -). Cells of germinocyte phenotype (CD10+, DNA7+) were sparsely seen. A good number of intramucosal lymphoid cells were further labeled for CD11b, a phenotype of so-called B-1 cells. Plasma cells were clustered within the basal half. IgG was their major immunoglobulin class, followed by IgA, IgM and lgD classes. A smaller number of T cells (CD2+, CD3+, CD5+, CD45RO+, TCR αβ+) were identified among the epithelium. CD4+ cells predominated over CD8+ cells. TCR γΔ + cells were rare. Macrophages (CD68+), dendritic histio-cytes (S-100 protein+, CD1+), and natural killer cells (CD16+ or CD57+) were also dispersed. Another unique feature of this lymphoepithelial complex was the existence of HLA-DR intramucosal microvasculature, where lymphocyte recirculation was suggested. Proliferating cell nuclear antigen was detected commonly in the epithelial cells but rarely in the lymphoid cells. Possible lymphoepithelial interactions and morphologic similarities to the thymic medulla are discussed. 相似文献
83.
茶色素治疗糖尿病前后血液流变性和微循环检测分析 总被引:1,自引:0,他引:1
目的:观察茶色素治疗糖尿病前后血液流变微循环的变化。方法:糖尿病人88例,男71例,女17例,年龄32~64岁。口服茶色素2粒(250mg),每日3次,疗程为30天。结果:血液流变学参数、微循环积分值、血生化指标、RIA都有明显改善(P<0.01或P<0.05)。结论:茶色素可以明显改善糖尿病人血液流变性和微循环多项检测指标,值得临床推广应用。 相似文献
84.
Dvorak Abeliovich Esther Maor Nava Bashan Rivka Carmi 《American journal of medical genetics. Part A》1989,32(3):346-349
We report on three patients with duplication of distal 22q. One patient is a de novo carrier of the translocation t(21;22) (p13;q11), the other two are offspring of a translocation carrier t(10;22) (q26;q12). The clinical manifestations of these patients demonstrate the variability of the dup(22q) syndrome. 相似文献
85.
Paloma E Coco R Martínez-Mir A Vilageliu L Balcells S Gonzàlez-Duarte R 《Human mutation》2002,20(6):476-476
Genotype-phenotype correlations highlighted the function of ABCA4 in retinitis pigmentosa (RP),cone-rod dystrophy (CRD) and Stargardt/Fundus Flavimaculatus disease (STGD/FFM). Initial screening of ABCA4 variants showed a correlation between the type of mutation and the severity of the disease. In the present study we have undertaken mutational and haplotype analysis of ABCA4 in three mixed pedigrees segregating different retinal dystrophies. In family I, we have shown cosegregation of different ABCA4 alleles with CRD (homozygosity for L1940P) and three subtypes of STGD/FFM. The first, a mild form, consisting on fundus flavimaculatus-like distribution of flecks, but good visual acuity and absence of dark choroid, was found to cosegregate with alleles R1097C and F553L; the second, a conventional Stargardt phenotype was associated to alleles L1940P/R1097C and the third, displaying severely reduced visual acuity and dark choroid (named FFM), was associated to L1940P/F553L. In family II, segregating STGD and RP phenotypes, while the involvement of ABCA4 in STGD seems clear this is not the case for RP. Finally, in family III, also segregating STGD and RP, ABCA4 fails to explain either phenotype. Our data highlight the wide allelic heterogeneity involving this gene and support the genetic variability (beyond ABCA4) of mixed STGD/RP pedigrees. 相似文献
86.
C S Lee E Meeusen K Gogolin-Ewens M R Brandon 《American journal of reproductive immunology (New York, N.Y. : 1989)》1992,28(2):90-96
PROBLEM: Previous studies have revealed the presence of a unique population of CD45R+ granulated cells in the sheep uterine epithelium. In the present study, dramatic changes in this cell population and in the nongranulated lymphocytes in the uterine and endometrial glandular epithelium of non-cycling, cycling, pregnant, and postparturient sheep are described. In noncycling and cycling sheep, the granules in the granulated intraepithelial cells were small. From days 55 to 134 of pregnancy, the granules in these cells were large, and there was a significant increase (P < 0.01) in the proportion of this cell population in the uterine epithelium but not in the endometrial glandular epithelium located in the deeper region of the stroma. The number of these cells declined dramatically (P < 0.01) from 2 to 15 days after parturition. Both the tissue distribution and the time of activation of these cells suggests they are different from the granulated lymphocytes described in placentae of mice and man. CONCLUSIONS: It is concluded that this unique population of granulated cells is derived from lymphocytes, and that these cells become metabolically active from mid- to late-pregnancy and may play a physiological role during pregnancy or birth. In contrast, the number of nongranulated intraepithelial lymphocytes were suppressed throughout pregnancy and they probably do not play a role in pregnancy. 相似文献
87.
Mitchell A. Watsky Kim Cooper James L. Rae 《Pflügers Archiv : European journal of physiology》1991,419(5):454-459
Voltage-gated, tetrodotoxin(TTX)-blockable sodium channels are found in most excitable cells and are the primary contributors to action potentials generated by many of these cells. To date, there has only been one report of a non-cultured vertebrate epithelial cell type containing TTX-blockable Na+ channels: rabbit non-pigmented ciliary body epithelial cells [Cilluffo MC et al. (1991) Invest Opthalmol Vis Sci 32:1619–1629], and three reports of cultured epithelial cells containing TTX-blockable Na+ channels: rabbit non-pigmented and pigmented ciliary body epithelium [Ciluffo MC et al. (1991) Invest Opthalmol Vis Sci 32:1619–1629; Fain GL, Farahbakhsh (1989) J Physiol (Lond) 417:83–103] and human lens epithelium [Cooper K et al. (1990) J Membr Biol 117:285–298]. We report here the presence of sodium currents in two different non-cultured, freshly dissociated transporting epithelial cell types: the rabbit corneal endothelium and the frog lens epithelium. We also report the occurrence of sodium currents in six additional cultured ocular epithelial cell types from three different species. These currents have a current/voltage (I/V) relationship consistent with traditional voltage-gated Na+ currents, are quinidine- and TTX-blockable (of the low-affinity TTX-sensitive type), and disappear following bath substitution of Na+ with Cs+ or K+. 相似文献
88.
虹膜组织力学特性及瞳孔阻滞力定量研究的方法学探索 总被引:6,自引:0,他引:6
目的:寻找一种能对虹膜本构关系以及原发性闭角型青光眼瞳孔阻滞力进行定量研究的方法,为闭角型青光眼的早期诊断及治疗方法的选择和治疗效果的评价提供一种定量标准.方法:根据瞳孔阻滞产生机制,设计瞳孔阻滞力仿真方法;依据力学原理和自定义的虹膜面应变、面积模量等建立虹膜的本构关系.结果:设计了一种不破坏虹膜正常功能和形态学结构,对虹膜组织力学特性及瞳孔阻滞力进行定量研究的方法. 相似文献
89.
Nils Koppang 《American journal of medical genetics. Part A》1992,42(4):599-604
The etiology of the juvenile type of the human ceroid-lipofuscinosis (JCL) is unknown, in spite of the fact that the first report of this disease was given more than 160 years ago. The necessity of good animal models for scientific progress in chronic metabolic diseases in humans is obvious. The inbred strain of English setter with ceroid-lipofuscinosis (CCL) seems to be a perfect model for human JCL. Dogs with CCL and organs for research purposes are available from Dr. Koppang's experimental kennel in Norway. 相似文献
90.
Jörns J Mangold U Neumann U Van Damme EJ Peumans WJ Pfüller U Schumacher U 《Anatomy and embryology》2003,207(1):85-94
Cellular interactions within the immune system are in part mediated via the carbohydrate-rich coat of the cell membrane, the glycocalyx, of which the terminal carbohydrate residues are of particular functional importance. Thus, these carbohydrate residues from thymus, bursa of Fabricius, spleen and bone marrow of 2- and 30-day-old chickens were investigated by lectin histochemistry. In the thymus, mannose as well as N-acetyl-glucosamine (glcNAc)-specific lectins labelled macrophages, epithelial reticulum cells and lymphocytes within the cortex. In the bursa of Fabricius, the brush border of the lining epithelium, the macrophages and the endothelium were labelled by mannose-specific lectins. The follicle-associated epithelium was labelled by a broad spectrum of lectins. Epithelial cells that separated the cortex from the medulla and large mononuclear cells in the cortex were only being labelled by N-acetyl-galactosamine (galNAc)-specific and glcNAc-specific lectins, respectively. In the spleen, lymphocytes of the peri-ellipsoid lymphocyte sheaths and macrophages of the red pulp were labelled by lectins of nearly all sugar specificities. In general, glycotopes of these organs were more intensively labelled in the 2-day-old chicken than in the 30-day-old chicken, indicating changes in glycotope expression during post-hatching development. Thus, cells of the avian immune system are as rich and diverse in their lectin binding sites as their mammalian counterparts, indicating that similar carbohydrate lectin interactions between cells and matrices take place in birds as well. 相似文献