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991.
The surface phenotypes of lymphoid cells in the developing embryonic thymus were characterized by using monoclonal antibodies. FT-2 antigen thus defined was predominantly expressed on thymocytes in the earlier embryonic stages in all the inbred mouse strains tested. The immunofluorescence and immunoperoxidase tests indicated that, like FT-1 antigen, the proportion of FT-2+ fetal thymocytes rapidly decreased with increase in gestation time, and these cells disappeared by day 19 of gestation. The treatment of fetal thymocytes with anti-FT-1 plus complement eliminated not only FT-1+, but also FT-2+ cells, whereas the treatment with anti-FT-2 failed to eliminate approximately 40% of FT-1+ cells, suggesting that embryonic thymocytes can be provisionally divided into at least three subpopulations, FT-1+2+, FT-1+2- and FT-1-2-. 相似文献
992.
Ia antigens were shown to be present in the cell almost exclusively as mature alpha beta dimers which split into separate alpha and beta chains after boiling in SDS. In contrast metabolically labelling the cells with [35S]methionine resulted in only free alpha and beta chains being labelled. It is concluded that this widely used type of labelling, although useful for studying intermediate synthesis, should not be used for labelling mature cell surface molecules. 相似文献
993.
Dr. Dr. K. Kayser H. -U. Burkhardt W. Jacob 《Virchows Archiv : an international journal of pathology》1978,380(2):155-162
Summary The advantages of a population-based registry are discussed. It is shown that a registry for gastro-intestinal cancer in a district with expert medical care based upon histo-pathological diagnosis, has the principal advantage that it limits the sites of material collection to a few effective contributors, thus providing highly accurate data. The disadvantage of collecting data by two separate steps should be tolerated. The geographic situation and the organization of the regional registry for gastro-intestinal cancer in North Baden are described and the incidences for these cancers for the years 1971–1975 are given for the population of 2.2 million.Supported by the DFG (SFB 136) 相似文献
994.
D. N. Mayanskii V. I. Shcherbakov Yu. M. Mirokhanov 《Bulletin of experimental biology and medicine》1977,84(5):1644-1646
The system of mononuclear phagocytes of the liver was blocked in male Wistar rats weighing 140–160 g by iron carbonyl (brand R-100 F) with a particle size of 1–1.5 . The blockade was carried out 2 h before partial hepatectomy and also 3 and 18 h after the operation. Injection of the iron compound before the operation and in the early prereplicative period of regeneration led to substantial delay of the peak of the index of labeled nuclei and mitotic index of the hepatocytes accompanied by a general reduction in proliferative power of the hepatocytes. Blockade of the system of mononuclear phagocytes in the period of intensive DNA synthesis by hepatocytes of the regenerating liver was less effective. The facts are evidence of the important role of the Kupffer cells in regulation of reparative regeneration of the liver.Laboratory of Pathophysiology, Department of General Pathology, Institute of Clinical and Experimental Medicine, Siberian Branch, Academy of Medical Sciences of the USSR, Novosibirk. (Presented by Academician of the Academy of Medical Sciences of the USSR V. P. Kaznacheev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 11, pp. 616–618, November, 1977. 相似文献
995.
Mice expressing transgenic T cell receptors (TCR) are used to explore important questions in immunity. However, transgene expression may have unexpected effects. We previously reported a B cell immunodeficiency, comprising decreased B cell numbers and diminished antibody responses, in mice that express a transgenic TCR specific for nicotinic acetylcholine receptor; the mice were generated using cassette vectors designed specifically for transgenic TCR expression [see Kouskoff et al. J. Immunol. Methods 1995. 180: 273-280]. We now show data suggesting that this defect is due to the expression and accumulation of TCR alpha and beta chains inside B cells and induction of an endoplasmic reticulum stress response, causing apoptosis at the pre B-I and later B cell stage. Thus, inappropriate transgene expression can profoundly affect B cells, leading to a previously undescribed mechanism of immunodeficiency. 相似文献
996.
M. Ishizawa K. Matsumoto S. Kukuda H. Okabe K. Hodohara S. Ota 《Virchows Archiv : an international journal of pathology》1995,427(1):105-110
Two cases of anaplastic large cell Ki-1 lymphoma involving bone as the most prominent and initial manifestation are reported. The first patient was a 20-year-old male who had back pain and incomplete paraparesis due to vertebral involvement. The second was a 14-year-old girl, whose first clinical signs were fever of unknown origin and sternal bone pain. Radiologically, skeletal lesions were lytic and destructive. Histopathologically, the tumour cells had pleomorphic bizarre nuclei and abundant basophilic cytoplasm. Immunohistochemically, Ki-1 (CD30) reactivity was strongly positive in both cases. Tumour cells were also CD3, CD4, epithelial membrane antigen and interleukin-2 receptor positive in the first case, and CD10, HLA-DR positive in the second case. The former tumour was considered to be of T-cell lineage and the latter of lymphoid progenitor cell origin. Radiation and chemotherapy were temporarily effective. However, both patients died 14 and 7 months after diagnosis, respectively, due to systemic lymph node involvement. These observations suggest that the prognosis for Ki-1 lymphoma involving bone is poorer than indicated in previous reports. 相似文献
997.
从人膀胱上皮癌细胞株T24的亚克隆株T24-8的无血清培养上清液经55%硫酸铵沉淀,再对无离子水透析,得到了有诱导LAK 细胞活性的粗提品。有此作用的因子称为LAK 细胞诱导因子(LAK-IF)。它的分子量为67KD,等电点为pH3.1~3.5。抗人IL-6单抗不能阻断LAK-IF 的作用。LAK-IF 粗提品经Mono-Q 柱快速蛋白液相层析见3个峰。第2峰蛋白质有LAK-IF 活性。 相似文献
998.
999.
Safarova ER Shram SI Zolotarev YA Myasoedov NF 《Bulletin of experimental biology and medicine》2003,135(3):268-271
We studied the effects of Semax (antiinsulin peptide with neuroprotective effect) on the survival of cultured rat pheochromocytoma cell after oxidative stress induced by short-term incubation with hydrogen peroxide. Studies with fluorescent dyes propidium iodide and Hoechst 33258 showed that cell incubation with hydrogen peroxide led to the formation of damaged cells with characteristic signs of necrosis. Semax dose-dependently reduced the number of cells damaged by oxidative stress. The efficiency of Semax depended on the time of its addition to the culture medium. The results suggest that the neuroprotective effect of Semax in ischemic stroke can be due to its capacity to protect neurons from damage caused by oxidative stress. 相似文献
1000.
Kvacheva ZB Shukanova NA Votyakov VI Lobanok ES Vorobei AV Nikolaeva SN 《Bulletin of experimental biology and medicine》2003,135(4):384-387
Membranotropic amphiphilic chromophore merocyanine 540 sensitized photodynamic inhibition of drug-resistant and sensitive variants of type I herpes simplex virus in cultured Vero cell. Optimal conditions of photodamage to virus particles and infected cells were determined (merocyanine 540 concentration 1 M, illumination dose 32.5-65.0 kJ/m2, exposure at early stages of infection). Infected cells actively bind the photosensitizer, which explains their selective photodamage. 相似文献