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81.
82.
K. Wŀodarski S. Mazur M. Jakóbisiak 《Cellular and molecular life sciences : CMLS》1982,38(9):1105-1106
Summary The absolute number of mast cells in regional lymph nodes decreases on the 5th day after stimulation by allogeneic lymphocytes and semisyngeneic leukaemic cells, despite the enlargement of stimulated lymph nodes. It is postulated that the reaction of lymphatic mast cells could be a sensitive test for tissue incompatibility, and probably also for the presence of tumor associated antigens. 相似文献
83.
S. Barrigón J. Tamargo P. D. Garcia de Jalón 《Cellular and molecular life sciences : CMLS》1978,34(6):770-770
Summary Bunaphtide induces a blockade in the3H-norepinephrine uptake and retention in the isolated guinea-pig left atrium. However, this blockade does not seems to be related with the cardiodepressant effect of the drug. 相似文献
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Stockert J. C. Sogo J. M. Díez J. L. Giménez-Martín G. 《Cellular and molecular life sciences : CMLS》1969,25(7):773-774
Resumen Se describe el hallazgo de un bulbo deAllium cepa en el cual los dos nucleolos de cada nÚcleo muestran una clara diferencia de tamaño. El nucleolo menor posee aproximadamente la mitad del diámetro del nucleolo normal. Esta alteración de la morfología nucleolar se correlaciona con la ausencia de satélite en uno de los dos cromosomas normalmente satelizados.
The work reported in this paper was undertaken during the tenure of a Research Training Fellowship awarded by the International Agency for Research on Cancer. 相似文献
The work reported in this paper was undertaken during the tenure of a Research Training Fellowship awarded by the International Agency for Research on Cancer. 相似文献
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Résumé L'effet de la NADH et NAD+ sur la protéolyse de la lacticodéhydrogénase isoenzyme 1 (LDH 1) et isoenzyme 5 (LDH 5) par la trypsine fut étudié. Les résultats montrent que la NAD+ exerce une protection contre la protéolyse de la LDH 1. Mais ni la NADH ni la NAD+ ne protègent contre la protéolyse de la LDH 5. 相似文献
88.
Genetic and developmental basis of evolutionary pelvic reduction in threespine sticklebacks 总被引:1,自引:0,他引:1
Shapiro MD Marks ME Peichel CL Blackman BK Nereng KS Jónsson B Schluter D Kingsley DM 《Nature》2004,428(6984):717-723
Hindlimb loss has evolved repeatedly in many different animals by means of molecular mechanisms that are still unknown. To determine the number and type of genetic changes underlying pelvic reduction in natural populations, we carried out genetic crosses between threespine stickleback fish with complete or missing pelvic structures. Genome-wide linkage mapping shows that pelvic reduction is controlled by one major and four minor chromosome regions. Pitx1 maps to the major chromosome region controlling most of the variation in pelvic size. Pelvic-reduced fish show the same left-right asymmetry seen in Pitx1 knockout mice, but do not show changes in Pitx1 protein sequence. Instead, pelvic-reduced sticklebacks show site-specific regulatory changes in Pitx1 expression, with reduced or absent expression in pelvic and caudal fin precursors. Regulatory mutations in major developmental control genes may provide a mechanism for generating rapid skeletal changes in natural populations, while preserving the essential roles of these genes in other processes. 相似文献
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Abrescia NG Cockburn JJ Grimes JM Sutton GC Diprose JM Butcher SJ Fuller SD San Martín C Burnett RM Stuart DI Bamford DH Bamford JK 《Nature》2004,432(7013):68-74
The structure of the membrane-containing bacteriophage PRD1 has been determined by X-ray crystallography at about 4 A resolution. Here we describe the structure and location of proteins P3, P16, P30 and P31. Different structural proteins seem to have specialist roles in controlling virus assembly. The linearly extended P30 appears to nucleate the formation of the icosahedral facets (composed of trimers of the major capsid protein, P3) and acts as a molecular tape-measure, defining the size of the virus and cementing the facets together. Pentamers of P31 form the vertex base, interlocking with subunits of P3 and interacting with the membrane protein P16. The architectural similarities with adenovirus and one of the largest known virus particles PBCV-1 support the notion that the mechanism of assembly of PRD1 is scaleable and applies across the major viral lineage formed by these viruses. 相似文献