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71.
72.
M Dechamps B R de Saint-Vincent C Evrard M Sassi G Buttin 《Experimental cell research》1974,86(2):269-279
From a variety of independent Chinese hamster cell lines, stable variants resistant to 5 μg/ml of Ara-C were isolated via a single step selection; in contrast to variants selected at lower drug concentrations, the resistant clones appear to be uniformly deficient in Ara-C phosphorylation, an activity previously shown [14] to be carried out in hamster cells by a cytoplasmic dC-kinase (dC-kinase 2). These dC-kinase deficient (dCK?) variants can be selected against because they are unable to divide in a medium containing dT (0.8 mM) and dC (0.01 mM), which supports the growth of wild type dCK+ cells. Plating of dCK? cells in medium supplemented with both nucleosides yields only rare clones of pseudorevertants which escape the thymidine block through a secondary unknown defect; the growth of these clones can be prevented by further addition of dA to the selective medium. As expected from the complementation pattern for the deficient enzyme activities, hybrids between a dCK? hamster line and TK? lines of either mouse or hamster could be isolated in a modified HAT medium (HAT50dC) containing dC and an increased dT concentration. In principle, the same selection can be used to isolate interspecific and intraspecific hybrids between Ara-C resistant variants obtained from a variety of mammalian species and azaguanine resistant lines deficient in HGPRT. The potential interest of this sytem for genetic mapping is discussed. 相似文献
73.
The authors report two cases of optic hypoplasia associated with neurological abnormalities and discuss the anatomical, pathophysiological and genetic aspects of the "Septo-Optic Dysplasia". This syndrome is not a homogeneous condition. Available data suggest that the septo-optic dysplasia occurs as a consequence of an embryofoetopathy and not of a genetically determined failure of development. The genetic counselling is described. 相似文献
74.
Involvement of semenogelin-derived peptides in the antibacterial activity of human seminal plasma 总被引:9,自引:0,他引:9
Bourgeon F Evrard B Brillard-Bourdet M Colleu D Jégou B Pineau C 《Biology of reproduction》2004,70(3):768-774
Mechanisms for protecting spermatozoa, and the testes that produce them, from infection are essential, given the importance of these cells and organs for the fertility of the individual and perpetuation of the species. This is borne out by the publication of numerous papers on this subject over the last 50 years. We extended our work and that of others on the anti-infectious defense system of the male genital tract, using a new strategy for the direct identification of antibacterial molecules in human seminal plasma. We subjected a liquefied seminal plasma cationic fraction to reversed-phase HPLC, monitored microbicidal activity by gel overlay and radial diffusion assays, and identified the proteins and/or peptides present in each active fraction by mass spectrometry. In addition to proteins with known potent microbicidal activity--phospholipase A2, lactoferrin, and lysozyme--we also found that peptides produced by cleavage of semenogelin I, the predominant human semen coagulum protein, had high levels of antibacterial activity. 相似文献
75.
The hormone testosterone (T) is involved in the control of aggressive behavior in male vertebrates. T enhances the frequency and intensity of aggressive behaviors during competitive interactions among males. By promoting high-intensity aggression, T also increases the risk of injury and presumably the perception of painful stimuli. However, perception of painful stimuli during fights could counteract the expression of further aggressive behavior. We therefore hypothesize that one function of T during aggressive interactions is to reduce nociception (pain sensitivity). Here, we experimentally document that T indeed reduces behavioral responsiveness to a thermal painful stimulus in captive male house sparrows (Passer domesticus). Skin nociception was quantified by foot immersion into a hot water bath, a benign thermal stimulus. Males treated with exogenous testosterone left their foot longer in hot water than control birds. Conversely, males in which the physiological actions of testosterone were pharmacologically blocked withdrew their foot faster than control birds. Testosterone might exert its effects on pain sensitivity through conversion into estradiol in the dorsal horn of the spinal cord. Decreased nociception during aggressive encounters may promote the immediate and future willingness of males to engage in high-intensity fights. 相似文献
76.
Evrard DA Zhou P Yi SY Zhou D Smith DL Sullivan KM Hornby GA Schechter LE Andree TH Mewshaw RE 《Bioorganic & medicinal chemistry letters》2005,15(4):911-914
Derivatives of the serotonin reuptake inhibitor 4-(5-fluoro-1H-indol-3-yl)cyclohexylamine, in which serotonin 1A (5-HT(1A)) receptor pharmacophoric elements are incorporated, are reported. Analogs exhibiting affinity for both the serotonin transporter and the 5-HT(1A) receptor are described. Compounds containing 1-(4-indolyl)piperazine and 2-(1H-indol-4-yloxy)ethylamine are promising leads for further SAR studies. 相似文献
77.
Residence rule flexibility and descent groups dynamics shape uniparental genetic diversities in South East Asia
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78.
79.
J Troquet P Hourlay P Evrard J Halleux 《Comptes rendus des séances de la Société de biologie et de ses filiales》1980,174(5):863-866
An accurate representation of the thoracic surface is required to solve the inverse problem of electrocardiography. For the purpose we have searched the second degree surface which fits 55-88 positions distributed around the trunk. Over a group of 17 young men, we have found that the positions always scattered around an ellipsoid the cephalo-caudal limits of which extended far away from the zero potential gradient levels. This discrepancy is discussed and a proposal is formulated. 相似文献
80.
Angela CM Luyf Barbera DC van Schaik Michel de Vries Frank Baas Antoine HC van Kampen Silvia D Olabarriaga 《BMC bioinformatics》2010,11(1):598