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811.
812.
Synthesis and some characteristics of [13C]-specially enriched tetragastrin and the related compound
[13C]-enriched tetragastrin and the related compound were synthesized in solution. Conversion of S-[13C]methylated tetragastrin to the enriched tetragastrin gave 10.5 ppm upfield chemical shift of Cepsilon resonance. The potency of the synthetic tetragastrin to stimulate gastric acid secretion was virtually identical with that of pentagastrin (ICI). 相似文献
813.
The N-terminal fragments (residues 1-51 and 1-59) obtained by selective tryptic cleavage of native lac repressor retain the ability to bind DNA. These fragments (headpieces) are monomeric and form complexes which resemble those of tetrameric repressor with non-operator DNA. But, they do not show the high specificity of repressor for operator sequences. The DNA binding has been demonstrated by filter-binding assay as well as in solution using absorption, circular dichroism, and fluorescence measurements. 相似文献
814.
815.
Epstein-Barr virus genome-positive T lymphocytes in a boy with chronic active EBV infection associated with Kawasaki-like disease 总被引:21,自引:0,他引:21
H Kikuta Y Taguchi K Tomizawa K Kojima N Kawamura A Ishizaka Y Sakiyama S Matsumoto S Imai T Kinoshita 《Nature》1988,333(6172):455-457
Epstein-Barr virus (EBV), a ubiquitous human herpesvirus and an aetiological agent of infectious mononucleosis, has a unique tropism for B lymphocytes. Clinical and laboratory features of chronic active EBV infections are chronic or persistent infectious mononucleosis-like symptoms and high antibody titre against early antigens (EA). Kawasaki disease (KD), aetiology unknown, is thought to be self-limited immunologically mediated vasculitis. Clinical features of KD are fever, rash, mucositis, lymphadenopathy and coronary artery damage. We report here a child with chronic active EBV infection accompanied by dilatation of coronary arteries. All the EBV-determined nuclear antigen (EBNA)-positive lymphocytes had exclusively CD4 antigen, as revealed by dual staining immunofluorescence analysis. Southern blot hybridization showed that the purified CD4+ cells harboured EBV genome. 相似文献
816.
D. Galdean D. Petrasincu P. Alangiu S. Ibric N. Voiculetz 《Cellular and molecular life sciences : CMLS》1986,42(5):572-574
Summary The protective effect of Thiola against the genotoxicity, induced by benzo(a)pyrene, in vitro and in vivo, was investigated. By association of Thiola to benzo(a)pyrene a significant decrease of the numerical and structural chromosome aberrations and a reduction of the incidence of c-mitoses has been obtained in human diploid cells, i.e. human embryonic lung fibroblasts of the cell-line ICP-23, and C56Bl/6 mouse bone marrow cells. 相似文献
817.
M. E. Hoffmann D. B. Ciampi N. Duran 《Cellular and molecular life sciences : CMLS》1987,43(2):217-220
Summary A radical anion of 2,3,5,6-tetrahydroxy-2,5-cyclohexadiene-1,4-dione was detected using the EPR technique by complexing with Zn ions. Hydrogen peroxide, superoxide radical anion and hydroxyl radical were also detected in the reaction mixture. Kinetic study and product distribution indicated a probable mixed type one- and two-electron transfer mechanism. A possible relationship between the autooxidation process and the biological activity of substituted quinones was suggested. 相似文献
818.
Regulation of transcription. Flexible interpretation 总被引:1,自引:0,他引:1
819.
Anita Pakrashi P. L. Pakrasi S. N. Kabir 《Cellular and molecular life sciences : CMLS》1979,35(6):843-844
Summary Oral administration of p-coumaric acid to estrogen-primed immature female mice exerts neither estrogenic nor anti-estrogenic activity, but when it is administered to cyclic female mice in single dose at proestrus or in repeated doses, induces alteration in estrus cycle, ovarian and uterine weight and structure.The authors wish to thank Dr S. C. Pakrashi and his associates of Medicinal Chemistry Department for isolating the compound. Thanks are also due for granting Senior Research Fellowship to P.P. and Junior Research Fellowship to S.N.K. respectively. 相似文献
820.
S. Pearson P. B. Nunn N. Joan Abbott 《Cellular and molecular life sciences : CMLS》1979,35(10):1363-1364
Summary The action potential in amphibian sciatic nerve in vitro has been reported to be abolished by the topical application ofLathyrus sativus seed extract. We have confirmed this effect, but find that it is probably caused by the high K+ content of such seed extracts and that organic neurotoxins are not implicated.Acknowledgments. We thank the Wellcome Trust for financial support, Professor M.W. Bradbury for help with the ion determinations and Miss M.B. Burbridge of the Tropical Products Institute, London, for obtaining seed from Bombay, India. 相似文献