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921.
G R Azzali 《Experientia》1977,33(12):1638-1639
The histochemical and ultrastructural changes produced by zeranol treatment on the endometrium and the gonadotropic FSH cells of the adenohypophysis have been investigated in mice at the prepuberal and virginal stages. Modifications similar to those induced by estrogen treatment were observed. It is concluded that both estrogens and zeranol share the same activity on the tissues examined. 相似文献
922.
Summary The red anthraquinone derivative isolated from several Drechslera and Curvularia species has been identified as cynodontin (1,4,5,8-tetrahydroxy-2-methylanthraquinone), and not as 1,4,5,8-tetrahydroxy-2,6-dimethylanthraquinone as reported earlier. Both pigments showed similar physico-chemical properties. A good distinction could be obtained by gas-liquid chromatography. 相似文献
923.
924.
Summary Cells produced in the crypts of newborn pig ileum migrate onto villi during development. There is little or no corresponding loss of cells from villus tips during the first week of postnatal life. Villus growth during this period is largely responsible for the slow rate of cellular renewal seen to take place. 相似文献
925.
J H Saurat E Gluckman L Didierjean 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1977,285(4):355-356
By means of indirect immunofluorescence with human sera it has been demonstrated that cytoplasmic components of the basal cell layer showed antigenic differences as compared to the upper cell layers. Moreover there were differences whether the cells were involved in a mucous, a parakeratinized or an orthokeratinized differentiation. 相似文献
926.
G. Signorini S. Bucci-Innocenti M. Ragghianti F. Giorgi 《Cellular and molecular life sciences : CMLS》1979,35(10):1384-1386
Summary The hematic yolk precursor — vitellogenin — has been identified immunochemically in the serum of estrogenized females of the newtTriturus cristatus by employing an antiserum prepared against yolk proteins. 相似文献
927.
928.
HLA-restricted T-cell recognition of Epstein-Barr virus-infected B cells 总被引:23,自引:0,他引:23
In mice the cytotoxic T-cell response to several types of virus is influenced by genes within the major histocompatibility complex; in particular, genetic control is exercised at the effector cell level through a requirement that virus-specific cytotoxic T cells recognise viral antigens in association with H-2K and H=2D region gene products on the surface of infected cells. In man the restriction which the analogous HLA-A, -B and -C-region gene products might place on virus-specific T-cell function is still in dispute. The earliest and most controversial evidence concerns the Epstein-Barr virus (EBV), a B lymphotropic agent which causes infectious mononucleosis (IM) and which induces an unusually vigorous T-cell response; cytotoxic T cells from IM patients' blood were shown to be EBV-specific yet, in contrast to mouse systems, apparently free of any obvious HLA restriction. Since then T-cell recognition of EBV-infected B cells has assumed particular significance as a model system for the study of cytotoxic T-cell function in man. This report describes the results of a new approach clearly indicating that HLA-A and -B region products do indeed have a role in this system. 相似文献
929.
H. E. Gray S. E. Wenzel W. G. Luttge S. F. Zornetzer 《Cellular and molecular life sciences : CMLS》1979,35(8):1126-1127
Summary An apparently transient elevation of basal morning (08.00 h) plasma corticosterone levels in male mice was found 48 h after bilateral electrolytic lesions of the brainstem locus coeruleus complex but was not observed 6 weeks after lesioning.Supported by Alfred P. Sloan Foundation research fellowships awarded to W.G. Luttge and S.F. Zornetzer. 相似文献
930.
Riassunto Vengono riportati i dati relativi allo sviluppo in funzione dell'età, della reatività immunologica primaria nel topo con nanismo ereditario preipofisario e nel corrispondente fratello normale. Mentre in quest'ultimo si è notato un graduale incremento della reattività immunitaria di tipo primario soprattutto a partire dalla fine del periodo di allattamento, nel topo nano la reattività immunitaria primaria è rimasta costante nel tempo su bassi livelli anche dopo lo svezzamento. Alla luce dei dati sperimentali riportati viene ipotizzata l'esistenza di un controllo ipofisario della reattività immunitaria primaria. 相似文献