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911.
K. Silberbauer H. Sinzinger Maya Winter W. Feigl F. Ring 《Cellular and molecular life sciences : CMLS》1978,34(11):1471-1472
Summary Morphological control of Moncada's bioassay for prostacyclin (PG I2) activity measurement shows that the activity depends not only on endothelium, but in important amounts on subendothelial tissue too. Therefore, it can be concluded that platelet thrombus formation after endothelial cell injury does not depend only on the PG I2-producing ability of the tissue. 相似文献
912.
913.
914.
Summary I.v. botulinum toxin after 60–90 min abolished the dose-response relationship between pentagastrin and gastric acid secretion in anesthetized rats and guinea-pigs. The toxin reduced but did not abolish the acid stimulatory effect of histamine. As expected, the acid response to vagal stimulation was abolished and that to methacholine in rats was unaltered by the toxin.Acknowledgment. We are grateful to the generosity of Dr Edward J. Schantz, Food Research Institute, University of Wisconsin, for the botulinum toxin used. — This research was supported by NIH grant 1 RO1 AM 17125, The Secretion of Pepsin. 相似文献
915.
The human B cell-specific alloantigen which is closely linked genetically to HLA contains two non-covalently associated, sialogycoprotein subunits of molecular weight (MW) 29,000 (p29), and 34,000 (p34). Although p29 and p34 have different amino-terminal sequences, their tyrosine peptide maps indicate considerable similarity in other portions of their polypeptide chains. Thus the genes for their proteins may have evolved by duplication of a common ancestral gene. Another lymphocyte cell surface protein of MW 16,000 (p16) has also been characterised. Both p16 and p44 (the heavy chain of HLA-A,B antigens) have been compared with p29 and p34. 相似文献
916.
917.
918.
Radioimmune, radiobinding and HPLC analysis of 2-5A and related oligonucleotides from intact cells 总被引:33,自引:0,他引:33
M Knight P J Cayley R H Silverman D H Wreschner C S Gilbert R E Brown I M Kerr 《Nature》1980,288(5787):189-192
The enzyme (2-5A synthetase) which synthesizes ppp(A2'p)nA where n=2 to 4 (collectively referred to as 2-5A) is widely distributed in a variety of cells and tissues in amounts which increase response to interferon and vary with growth and hormone status. 2-5A activates a nuclease which inhibits protein synthesis. The non-phosphorylated 'core' of 2-5A ((A2'p)nA, n=2 to 4) can inhibit DNA synthesis and cell growth. Here we describe convenient and sensitive radioimmune (RI) and radiobinding (RB) assays for core and 2-5A. In combination with more satisfactory high performance liquid chromatography (HPCL) methods using reverse-phase C18 columns, these assays have been used to detect core and 2-5A in crude extracts from interferon-treated cells. The novel 2-5A synthetase products NAD2'p5' A2'p5'A and A5'p45'A2'p5'A2'p5'A (ref. 13), which can also be detected using the RB assay, were not found in significant amounts. The natural occurrence of core has not been described previously. 相似文献
919.
920.
Three variable-gene pools common to IgM, IgG and IgA immunoglobulins 总被引:12,自引:0,他引:12