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151.
Brüls T Gyapay G Petit JL Artiguenave F Vico V Qin S Tin-Wollam AM Da Silva C Muselet D Mavel D Pelletier E Levy M Fujiyama A Matsuda F Wilson R Rowen L Hood L Weissenbach J Saurin W Heilig R 《Nature》2001,409(6822):947-948
We report the construction of a tiling path of around 650 clones covering more than 99% of human chromosome 14. Clone overlap information to assemble the map was derived by comparing fully sequenced clones with a database of clone end sequences (sequence tag connector strategy). We selected homogeneously distributed seed points using an auxiliary high-resolution radiation hybrid map comprising 1,895 distinct positions. The high long-range continuity and low redundancy of the tiling path indicates that the sequence tag connector approach compares favourably with alternative mapping strategies. 相似文献
152.
Helena de Souza Santos W. da Silva Sasso 《Cellular and molecular life sciences : CMLS》1973,29(4):473-474
Resumen Es estudiada la ultraestructure y la histochimica de gránulos de secreción de células glandulares mucosas del pié ambulacrario de la estrella de marEchinaster brasiliensis. Estos gránulos secretores tienen una organización distincta comparada con aqueles encuentrados en la estrella del marAsternia stellifera anteriormente estudiada. Así son organizados en forma de circolos concentricos en torno du un eixo.
Acknowledgments. The authors wish to express their thanks to Mrs.Arlene Mayhugh for her valuable technical assistance. This work was, in part, supported by grants from the Fundação de Amparo à Pesquisa do Estado de São Paulo, Brazil.
Pesquisadora-Conferencista do CNPq (TC 308-Proc. 9051/70). 相似文献
Acknowledgments. The authors wish to express their thanks to Mrs.Arlene Mayhugh for her valuable technical assistance. This work was, in part, supported by grants from the Fundação de Amparo à Pesquisa do Estado de São Paulo, Brazil.
Pesquisadora-Conferencista do CNPq (TC 308-Proc. 9051/70). 相似文献
153.
154.
Maria C. da Silva M. F. Gimeno A. L. Gimeno 《Cellular and molecular life sciences : CMLS》1977,33(4):481-483
Summary The electrically induced motility of isolated segments of guinea-pig sciatic nerves is reported. This motility was characterized by waves of tensional variations. The removal of Ca2+ from the suspending solution, the addition of EDTA as well as anoxia, resulted in a decrement of tension accompanied by a prolongued duration of the cycles of mechanical activity.This work was supported by grant 6638, from the Consejo Nacional de Investigaciones Cientificas y Técnicas de la República Argentina (C.O.N.I.C.E.T.). 相似文献
155.
Calcitonin in tissues of thyroidectomized monkey 总被引:1,自引:0,他引:1
K. L. Becker G. Geelhoed W. O'Neill K. G. Monaghan R. H. Snider C. F. Moore O. L. Silva 《Cellular and molecular life sciences : CMLS》1980,36(5):609-610
Summary Immunochemical studies indicate that immunoreactive calcitonin (iCT) is present in many tissues of monkey following thyroidectomy (thx) (e.g. liver, thymus, lung). Extrathyroidal iCT may play a role in calcium metabolism.Supported by the Ella O. Latham Trust, George Washington, NCI Grant RO1CA22137-02, and the Veterans Administration. 相似文献
156.
157.
Regulation of calcium signalling in T lymphocytes by the second messenger cyclic ADP-ribose 总被引:7,自引:0,他引:7
Guse AH da Silva CP Berg I Skapenko AL Weber K Heyer P Hohenegger M Ashamu GA Schulze-Koops H Potter BV Mayr GW 《Nature》1999,398(6722):70-73
Cyclic ADP-ribose (cADPR) is a natural compound that mobilizes calcium ions in several eukaryotic cells. Although it can lead to the release of calcium ions in T lymphocytes, it has not been firmly established as a second messenger in these cells. Here, using high-performance liquid chromatography analysis, we show that stimulation of the T-cell receptor/CD3 (TCR/CD3) complex results in activation of a soluble ADP-ribosyl cyclase and a sustained increase in intracellular levels of cADPR. There is a causal relation between increased cADPR concentrations, sustained calcium signalling and activation of T cells, as shown by inhibition of TCR/CD3-stimulated calcium signalling, cell proliferation and expression of the early- and late-activation markers CD25 and HLA-DR by using cADPR antagonists. The molecular target for cADPR, the type-3 ryanodine receptor/calcium channel, is expressed in T cells. Increased cADPR significantly and specifically stimulates the apparent association of [3H]ryanodine with the type-3 ryanodine receptor, indicating a direct modulatory effect of cADPR on channel opening. Thus we show the presence, causal relation and biological significance of the major constituents of the cADPR/calcium-signalling pathway in human T cells. 相似文献
158.
Nanog safeguards pluripotency and mediates germline development 总被引:3,自引:0,他引:3
Chambers I Silva J Colby D Nichols J Nijmeijer B Robertson M Vrana J Jones K Grotewold L Smith A 《Nature》2007,450(7173):1230-1234