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31.
The acidic aqueous solution of imogolite is proposed to be an ideal lyotropic system. No temperature dependence was marked on the two phase boundary concentrations (A and B points) of imogolite solutions as predicted by the theories of Flory and Onsager. A satisfactory quantitative agreement was observed with Onsager's theory. The polydispersity of rod lengths was found to shift the A point towards lower concentrations than expected from theory.  相似文献   
32.
Two cases of papillary type of C cell carcinoma of the thyroid were reported. They showed papillary arrangement with Abrovascular stalk in properly Axed tissues. Histochemically argyrophil reaction was positive in the cytoplasm and amyloid deposited in the stroma. Ultrastructurally secretory granules were found in their cytoplasm. The papillary type is not an artifact but one of the histologic variations of this carcinoma. ACTA PATH. SAP. 29: 653–659, 1979.  相似文献   
33.
A case of acquired immunodeficiency syndrome (AIDS) with preceding aplastic anemia is reported. The patient was a 36 year old female who had been diagnosed as having aplastic anemia 10 years before and thereafter had received multiple transfusions. Human immunodeficiency virus (HIV)-seropositivity was revealed 10 months prior to her death, but no particular clinical signs indicating HIV infection, pre-AIDS or onset of AIDS were recognized before serological diagnosis, although the slow progression of leukopenia was noted along with thrombocytopenia. Her general condition deteriorated during the last 10 months accompanied by an acute decrease In the CD4/CD8 ratio. Autopsy revealed full-blown AIDS: systemic aspergillosis, progressive multifocal leukoencephalopathy, Epstein-Barr virus-related B cell lymphoma arising in the diaphragm and severe lymphocyte depletion in the lymph nodes and spleen. Markedly hypo-plastic bone marrow was considered to be primarily attributable to the aplastic anemia but the affection of AIDS was not excluded. The possible transmission route of HIV and the effect of the preceding aplastic anemia on the infection and clinical course of AIDS are discussed.  相似文献   
34.
CD27 is a T cell activation antigen expressed on a majority of peripheral blood T cells. CD27 is also expressed on a subpopulation of human B cells, and it is reported that CD27+ B cells secrete both IgG and IgM. CD70, a ligand for CD27, is expressed on activated T and B cells, suggesting an interaction between T and B cells via CD27/CD70 ligation. Here, we analyze B cell immunoglobulin synthesis using a CD70 transfectant and present functional data showing that B cells secrete large amounts of IgG and IgM as a result of the CD27/CD70 interaction. A flow cytometric analysis showed that CD27 expression was increased and CD70 was expressed on tonsillar and peripheral blood B cells after activation with Staphylococcus aureus Cowan strain (SAC) plus interleukin (IL-2). In addition, the proliferation of B cells was enhanced mildly by the addition of CD70 transfectant, and its proliferation was blocked by anti-CD70 mAb. More importantly, the CD70 transfectant enhanced IgG and IgM production by purified B cells greatly in the presence of SAC plus IL-2. The enhancement was completely blocked by the addition of either anti-CD70 mAb or anti-CD27 mAb. Strongly suggesting that the interaction of CD27 with its ligand, CD70, on B cells plays an important role in B cell growth and differentiation to produce IgG and IgM.  相似文献   
35.
We report on a 19-month-old girl with a derivative chromosome 9 and a recombinant chromosome 12 resulting from a maternal balanced complex rearrangement involving chromosomes 8, 9, and 12. The karyotype of the phenotypically normal mother was 46,XX,t(8;12) (9;12) (8qter→8p23::12q12→12q15::9q32→9qter;9pter→9q32::12q15→12qter;12pter→12q12::8p23→8pter). The child's karyotype was 46,XX,?9,?12, +der(9) (9pter→9q32::12q15→12qter),+rec(12) (12pter→12q15::9q32→9qter) mat. The child had severe growth retardation, minor anomalies including trigonocephaly, hypertelorism, broad nasal root, apparently low-set and posteriorly angulated ears, triangular face, pectus carinatum, clinodactyly of fifth fingers, and almost normal psychomotor development. To the best of our knowledge, there have been only 3 previous reports of recombination derived from parental complex chromosome rearrangements. In the recombination products, the chromosomes were apparently balanced and the offspring had no clinical abnormalities. The present case exhibited abnormalities and may have a submicroscopic aberration of 12q arising from crossing over during maternal meiotic pairing, although her chromosomes appeared to be balanced. © 1993 Wiley-Liss, Inc.  相似文献   
36.
The distribution of carcinoembryonic antigen (CEA) in human gastric adenocarcinoma cell lines (HPE-GAC-3 cells and HPE-GAC-2 cells) was determined immunohistochemically by indirect peroxidase-labeled antibody method at the light and electron microscopic levels. In GAC-3 cells that proliferated as non-adherent single cells, CEA was located in the perinuclear spaces, the endoplasmic reticulum, Golgi apparatus, vesicles, multivesicular body (MVB) and entire plasma membrane. Membrane CEA was shown to be internalized into MVB in GAC-3 cells. In GAC-2 cells that form an acinus, CEA was predominantly present along the microvilli of the lumina) surface and in glycocalyceal bodies, the vesicles which bud from the microvilli into the lumen. These results suggest that in poorly differentiated cancer cells CEA is transported over the entire cell surface, retained on the membrane and accumulated Into the cell by way of the MVB, but in well differentiated cancer cells the newly synthesized CEA is rapidly and predominantly transported to the luminal surface and rapidly released from the membrane into the lumen by way of the glycocalyceal body.  相似文献   
37.
To determine the role of free radical mechanisms in the pathogenesis of amyotrophic lateral sclerosis (ALS), cerebrospinal fluid concentrations of oxidized nitric oxide (NO) products (nitrite and nitrate) and reduced and oxidized forms of glutathione (GSH and GSSG, respectively) were compared between patients with the sporadic form of ALS (SALS) and controls. In the SALS patients, the nitrate levels were significantly higher (by 73%) in contrast to remarkably lower GSSG/GSH ratio, approximately 3-fold, compared to controls. These results suggest that NO production or oxidation is activated in SALS patients, leading to a decrease in superoxide radicals to oxidize GSH. The subsequent generation of a highly reactive anion, peroxynitrite, may play a causal role in the pathogenesis of SALS.  相似文献   
38.
Sheep anti-type IV collagen serum was intravenously administered to male mice of the BALB/c, C3H and ddY strains, and their kidneys were morphologically studied monthly for 10 months thereafter. By immunofluorescence, the sheep IgG was seen to have immediately become conjugated to the glomeruli, mainly in a mesangial pattern. Successively, autologous mouse C3 and IgG appeared with the same type of distribution. Within 3 to 4 months after the start of the experiment, mouse IgA also appeared in the mesangium, especially in ddY mice. The intensity and frequency of mesangial IgA deposition and the serum IgA level increased with time in this strain. BALB/c and C3H mice also showed the same tendency of mesangial IgA deposition, although to a lesser degree. In summary, it was concluded that mesangial IgA deposition was due to non-immunological local trapping, on the basis of the results obtained by ELISA analysis of the sera and renal eluate. Although the ddY mouse is known to show spontaneous mesangial IgA deposition associated with a high serum IgA level with aging, these characteristics were much accelerated and intensified by this antiserum treatment. The relation of this observation to the pathogenesis of human IgA nephritis is discussed.  相似文献   
39.
Focal glomerulonephritis was induced in rats, by a single intravenous injection of anti-Thy-1.1 antibody (ATS). One hour after the administration, the glomeruli of affected rats developed necrotic changes of the mesangial cells while after two hours, mesangiolytic changes appeared. From six days onwards, focal segmental mesangial proliferation which persisted until 30 days, occurred. This is thought to be the first report of experimental nephritis induced by pure anti-mesangial antibody.  相似文献   
40.
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