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991.
The authors confirmed the presence of endocrine cells for the first time in a normal breast as well as in a non cancerous lesion of the breast. One hundred and eighty eight blocks of normal breast tissues in 44 cases and 74 blocks of non cancerous lesions in 35 cases were examined. Argyrophil cells were found in one block from a normal breast and in one block from a phyllodes tumor. Argyrophil cells in the normal breast showed positive reaction to anti-endocrine granule constituent (EGC) antibody with immunohistochemical method. Argyrophil cells found in the phyllodes tumor gave positive reaction to both anti EGC and anti-serotonin antibodies. The present study is thought to be the first report in the literature of serotonin-positive cells in a non-cancerous breast lesion, a phyllodes tumor. Acta Pathol Jpn 41: 874-878, 1991.  相似文献   
992.
Antigenic competition is known to be a widespread phenomenon when using crude extracts of antigens (e.g., Escherichia coli cytoplasmic proteins) for immunization. This non-specific form of immune suppression can be partially overcome by passive immunization with antibodies against dominant antigens (which are the suppressive molecules) before injection of the antigenic mixture. Blocking these immunodominant antigens or antigenic determinants by a passively administered antibody permits antibody responses against hitherto weakly or non-immunogenic molecules.  相似文献   
993.
Adrenal chromaffin cells, obtained from a therapeutically aborted human fetus of about 11 weeks gestation, were cultured for 3 weeks in vitro and then transplanted to the striatum of rats. Transplanted cells became established through strands of tissue growing into the host striatum. No signs of inflammation or rejection were observed up to the time of sacrifice one month post-transplantation. Histofluorescence examination of the implanted areas showed many clusters of cells having an intensely positive catecholamine fluorescence with some of the cells developing conspicuous processes. This study, showing survival of cultured human adrenal chromaffin cells transplanted into rat brain tissue, might indicate the feasibility of using cultured human material for future human neuronal transplantation studies as a therapeutic measure.  相似文献   
994.
A case of papillary-cystic variant of acinic-cell adenocarcinoma is described. The cytologic findings differed significantly from the classic features of this tumor with smears showing large monolayer sheets and small papillary groups, no acinic structures or naked tumor cell nuclei, sparse cell dissociation and many vacuolated cells. © 1994 Wiley-Liss, Inc.  相似文献   
995.
Primed and unprimed lymphocytes are usually classified as separate subsets of cells, based on phenotypic and functional distinctions. In the case of CD4+ T lymphocytes, primed cells are thought to proliferate more vigorously, quickly and easily, and to release a different profile of cytokines, than their naive equivalent. However, most of these data were obtained from studies in which populations of lymphocytes were compared before and after antigenic stimulation, and therefore did not distinguish between the effects resulting from the clonal expansion of specific precursor cells within such populations and those due to cell differentiation per se. We have investigated the contribution of precursor cell frequency to some of the functional changes observed in populations of CD4+ T cells following antigenic stimulation, using approaches in which antigen-specific precursor frequencies are high in both primary and secondary stimulations: mixed leukocyte reaction responses and cells from αβ T cell receptor transgenic mice. Our data suggest that when equivalent numbers of antigen-specific naive and previously primed CD4+ responder T cells are compared, there is no difference in their potency to proliferate but only the previously activated subset can generate cytokines such as interferon-γ.  相似文献   
996.
We have previously reported that gamma delta T cells play important roles in protection during the early stage of infection with Listeria monocytogenes in mice. To generalize the protective roles of gamma delta T cells in listerial infection to different species, we examined the appearance of gamma delta T cells during infection with L. monocytogenes in Fisher F344 rats. The numbers of bacteria in the peritoneal cavity and liver increased to a maximum level on day 3 and then decreased to an undetectable level by day 10 after an intraperitoneal infection with a sublethal dose (1 x 10(8)) of viable L. monocytogenes in rats. CD3+ alpha beta- T cells in the peritoneal cavity and liver began to increase on day 3, reached a maximum level on day 6, and thereafter decreased gradually by day 10 after infection. Northern blot analysis confirmed that the CD3+ alpha beta- T cells expressed TCR delta and gamma gene messages. In vivo treatment with anti-TCR alpha beta mAb, which suppressed most of the alpha beta T cells in the periphery and impaired resistance during the late stage of listerial infection, did not affect the host defense by day 6 after infection. A significantly increased number of gamma delta T cells was detected in the peritoneal cavity of the TCR alpha beta-suppressed rats on day 6 after infection. These results suggest that the early appearing gamma delta T cells may contribute to the host defense at a relatively early stage during listeriosis in rats.  相似文献   
997.
The association of Ig allotypes with celiac disease was analyzed in a sample of 95 Italian patients typed for HLA polymorphisms. No significant association was found for any Gm, A2m, or Km specificity when the overall sample was considered. However, significant different sex ratios were shown by patients' fnb positive and fnb negative genotypes, with a relative risk of 10.7 for this haplotype in males, suggesting that sex and Gm influence the penetrance of the HLA-linked genes. The significance of this finding is strengthened by the recent report that H-2 and Ig allotypes intervene in the genetic control of murine immune response to A-gliadin (M.F. Kagnoff, Nature 296:158, 1982).  相似文献   
998.
Purification of P-selectin (CD62P) from human platelets   总被引:1,自引:0,他引:1  
Summary A method is described for immunoaffinity purification of P-selectin from outdated human platelets.  相似文献   
999.
A patient with von Hippel Lindau disease, bilateral symmetric renal cell carcinoma and pulmonary metastases treated with immunotherapy is the subject of this study. A left kidney and tumour mass were removed and the tumour cells used to make an autologous tumour/bacille Calmette–Guérin (BCG) vaccine as part of the treatment protocol. The patient's pulmonary nodules responded, but the remaining renal nodule subsequently grew. Samples of both tumours were obtained allowing for an internally controlled evaluation of the histological and immunohistologic differences between a responding and non-responding tumour nodule after therapy. The immunotherapy protocol is designed to promote a T cell response to autologous tumour. Cellular infiltrates were demonstrated in both responding and non-responding nodules compared with the pretreatment tumour specimen, but the responding nodule contained proportionately more T cells as well as markedly increased numbers of plasma cells and granulocytes. This suggested that several arms of the immune system may have been operative in the responding nodule.  相似文献   
1000.
CD16, the type III receptor for IgG, is expressed on neutrophils, natural killer cells, and some T lymphocytes, mast cells, and activated monocytes but not on cells of the B-lymphocyte lineage including plasma cells. It is also produced in a soluble form found in serum. We analyzed sera from 165 multiple-myeloma patients, 29 patients with monoclonal gammopathies of unknown significance, and 20 normal disease-free donors. We found that the level of soluble CD16 was significantly decreased in sera from patients with multiple myeloma compared to sera from healthy and monoclonal gammopathies of unknown significance donors (P=0.0001). In addition, a stage-dependent decrease in soluble CD16 was observed, with a highly significant difference (P=0.004) between stage I and stage II+III myeloma patients. The correlation between the myeloma stage and the serum level of soluble CD16, which is related to the host response, was found to be more sensitive than that of 2-microglobulin, which reflects the tumor burden. The concomitant evaluation of the serum levels of these two markers allows better staging and therefore has a more precise prognostic value.  相似文献   
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