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21.
A. V. Filatov S. A. Prokof'ev V. V. Shcherbukhin 《Bulletin of experimental biology and medicine》1992,114(5):1656-1659
Institute of Immunology, Ministry of Health of Russian. (Presented by Academician of the Russian Academy of Medical Sciences R. V. Petrov.) Translated from Byulleten Éksperimental'noi Biologii i Meditsiny, Vol. 114, No. 11, pp. 506–508, November, 1992. 相似文献
22.
A quantitative immunocytochemical study of large granular lymphocytes (LGLs) in the normal cervix and in human papillomavirus (HPV) associated disease was performed using a panel of monoclonal antibodies which included those for LGL surface markers CD56, CD16, and CD57. Only CD56-positive cells were found within the ectocervical epithelium and these cells increased in number in cervical intraepithelial neoplasia (CIN) in comparison with normal cervix. Examination of serial sections and double labelling suggests that these cells are CD3+, CD8+, CD56+, CD16+. The observed increase in number of this subset was not associated specifically with HPV infection but was related to CIN. Lymphocytes expressing all three LGL markers were found in the stroma and CD16(+)-positive cells clustered around endocervical glands with occasional cells extending into the endocervical epithelium. These results indicate that a small subset of LGLs which express T-cell markers is increased in number in CIN. Cells expressing classical NK markers are restricted to the stroma and are not found within the ectocervical epithelium. 相似文献
23.
IgM allotype heterozygous F1 mice were independently suppressed for Igh6a or Igh6b to
evaluate the contribution of B-1 and B-2 cells to natural serum IgM levels and Ab responses.
B-2 B cells expressing IgM of the suppressed allotype were evident in the spleens of
suppressed mice 4 to 6 weeks after cessation of the suppression regimen, whereas B-1 B
cells of the suppressed allotype were undetectable for up to 9 months. Although serum IgM
of the suppressed allotype was initially depleted in mice suppressed for either allotype, by
7 months of age, there were detectable levels of IgM of the suppressed allotype in the
serum; however, the levels were significantly below that found in nonsuppressed mice.
When mice were immunized with either the T-independent or T-dependent form of
phosphorylcholine, those suppressed for either allotype, and consequently depleted of B-1
B cells of that allotype, did not respond with phosphorylcholine-specific IgM of the
suppressed allotype. In contrast, when mice were immunized with α1-3 dextran, the Igh6a
allotype-suppressed mice were able to produce dextran-specific IgM of that allotype. These
results show that allotype-bearing B-1 cells of both allotypes can be effectively suppressed
by this suppression protocol and this produces long-lasting effects on B-1 cell levels and
serum IgM of the suppressed allotype. These observations reflect the derivation of the
majority of B-1 cells from fetal-neonatal precursors, which cannot be replaced by newly
emerging B-2 cells of adult origin. Their ablation by antibody treatment results in
permanent alterations to the adult B-cell repertoire. 相似文献
24.
利用胸导管引流治疗哮喘病的机会,研究了PHA在rIL-2诱导胸导管淋巴细胞成为LAK细胞中的作用。结果表明:PHA和rIL-2共同诱导TDL2周,细胞数量扩增约34倍。同时明显促进了DL的~3H-TdR和~3H-Leucine的参入,较对照组有明显差异(P<0.01)。其中rIL-2 100~1000U/ml和PHA组作用最佳,但PHA和rIL-2的协同作用持续时间短,第6d即开始下降,而且PHA参与诱导的TDL-LAK细胞的杀伤活性有所下降。 相似文献
25.
简述了淋巴细胞亚群微核检测方法、淋巴细胞亚群自发微核率和影响因素,以及关于电脑射效应的研究现状,为微核法用于辐射生物剂的未来发展提供了有益信息。 相似文献
26.
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28.
Effects of zymosan-activated plasma and phorbol myristate acetate on isolated, perfused rabbit lungs
The effects of complement activation on pulmonary vascular permeability are disputed. In rabbit lungs perfused with autologous blood, zymosan activated plasma (ZAP) induced a moderate increase in pulmonary vascular resistance (PVR), but did not detectably change the vascular permeability within 2 h. The stronger neutrophil granulocyte (PMN) activator, phorbol myristate acetate (PMA), usually gave larger PVR increases and also increased pulmonary vascular permeability. Lungs from neutropenic animals, similarly perfused and given PMA, showed unchanged PVR reactions but had no apparent increase in vascular permeability. Lungs perfused with cell-free medium and given PMA displayed modest PVR increases, and no measurable permeability change. The lung preparatory procedure itself markedly influenced leukocyte circulation. Exsanguination of lung donors decreased the concentration of circulating PMN significantly, and they virtually disappeared from the perfusate within minutes after start of lung perfusion. PMN-mediated effects must therefore have been caused by cells already sequestered in the lungs. We conclude that ZAP does not induce an increased pulmonary vascular permeability in isolated, perfused rabbit lungs, in contrast to PMA. The permeability effects of PMA appear to be PMN dependent. 相似文献
29.
C De Simone A Misefari V Covelli A B Maffione S Antonaci E Jirillo 《Journal of clinical laboratory analysis》1989,3(6):345-349
The effects of substance P (SP) on Salmonella minnesota R345 (Rb) binding to human peripheral blood lymphocytes (PBL) were evaluated. Two parameters of bacterial cytoadherence were considered, namely the binding lymphocytes (BL) and the number of bound-bacteria/lymphocyte (BB). The results showed that SP inhibits both BL and BB in a significant manner. Furthermore, distribution of Salmonella binding to CD4+ and CD8+ lymphocytes was studied following SP pretreatment of lymphoid cells. This neuropeptide is able to hamper the bacterial cytoadherence to both T-cell subpopulations and, in particular, the inhibitory effect on the T-suppressor/cytotoxic subset was more pronounced. These findings are discussed in terms of SP intervention in the mechanism of host protection against invading microorganisms. 相似文献
30.
Stuart Sherman MD Nancy S. Nieland MD David H. Van Thiel MD 《Digestive diseases and sciences》1988,33(3):368-374
Summary An unusual case of a woman with primary biliary cirrhosis and cutaneous sarcoidosis is described. The factors that allow a specific diagnosis of each condition are presented and the literature pertaining to such complex and unusual cases is presented.This work was supported in part by a grant from the Gastroenterology Medical Research Foundation of Southwestern Pennsylvania. 相似文献