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Young S. Moon Basil Ho Yuen Sheila M. Pride Timothy C. Rowe Betty J. Poland Peter F. McComb Victor Gomel 《Molecular reproduction and development》1985,11(3):289-296
Between July 1982 and November 1983, two pregnancies were established using in vitro fertilization and embryo transfer (IVF and ET) procedures with three different schedules to induce follicular maturation. All women were cycling normally and had inoperable or absent fallopian tubes. Of 83 oocytes aspirated from 24 patients (31 cycles), 75% were considered mature and 25% immature by the morphological characteristics of the oocytes and cumulus cells. Oocytes were preincubated for 6–24 hours, and after insemination, 60% cleaved to the two-to-four-cell stage. The superovulation induction schedule employing hMG administered according to the individually adjusted treatment scheme established two pregnancies. This schedule was considered the superior regimen, as it gave the highest proportion of mature oocytes (89%) which cleaved (78%). The pregnancy-attaining follicle showed a high progesterone:estradiol-17β ratio (P4/E2) in its microenvironment of aspirated follicular fluid, culture media of granulosa cells, and oocyte-cumulus complex. Our observations indicate a high P4/E2 ratio in the pregnancy-attaining follicle, and thereby reflect a further parameter in influencing maturation of the oocytes most likely to implant. 相似文献
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δ9-THC, 11-OH-δ9-THC or placebo was administered to casual marihuana smokers in a double-blind, crossover study. δ9-THC and 11-OH-δ9-THC produced marked pharmacologic and psychologic effects (tachycardia, increased symptom score and psychologic high). In contrast to effects produced by many other centrally acting drugs, the acute administration of these cannabinoids was devoid of any significant effect on prolactin secretion as determined by monitoring changes in serum prolactin levels. 相似文献
957.
A scheme for the phage typing of Salmonella hadar 总被引:2,自引:0,他引:2
958.
Melissah Rowe Gábor Árpád Czirják Jan T. Lifjeld Mathieu Giraudeau 《Biological journal of the Linnean Society. Linnean Society of London》2013,109(1):92-100
Numerous antibacterial substances have been identified in the ejaculates of animals and are suggested to protect sperm from bacterial‐induced damage in both the male and female reproductive tracts. Lysozymes, enzymes that exhibit bactericidal activity through their ability to break down bacterial cell walls, are likely to be particularly important for sperm defence as they are part of the constitutive innate immune system and are thus immediately available to protect sperm from bacterial attack. Birds are an ideal model for studies of ejaculate antimicrobial defences because of the dual function of the avian cloaca (i.e. waste excretion and sperm transfer), yet the antibacterial activity of avian ejaculates remains largely unexplored, and data on ejaculate lysozyme levels are only available for the domestic turkey (Meleagris gallopavo). Moreover, ejaculate lysozyme levels have not been reported for any species in the wild; which many argue is necessary to gain a comprehensive understanding of the function and dynamics of immune responses. Here, we show that lysozyme is present in the ejaculate of a wild passerine, the superb fairy‐wren (Malurus cyaneus), and that the concentration of lysozyme in ejaculates varies substantially among males. This variation, however, is not associated with male condition, sperm quality or plumage coloration. Nevertheless, we suggest that lysozyme‐associated antibacterial activity in ejaculates may be the target of natural and sexual selection and that these enzymes are likely to function in defending avian sperm from bacterial‐induced damage. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 109 , 92–100. 相似文献
959.
Effect of n-alcohols and glycerol on the pretransition of dipalmitoylphosphatidylcholine 总被引:2,自引:0,他引:2
We have systematically investigated the effect of short-chain n-alcohols and glycerol on the pretransition of 1,2-dipalmitoylphosphatidylcholine (DPPC) by spectrophotometry. It is found that the n-alcohols and glycerol remove the pretransition above a critical concentration for each ligand. In addition, the short-chain n-alcohols below the critical concentration decrease the pretransition temperature. The longer the aliphatic chain length of the n-alcohol (up to butanol) the greater the decrease in the pretransition temperature, and the lower the concentration necessary to remove the pretransition. However, glycerol differs from the short-chain n-alcohols in that it has no significant effect on either the pretransition or the main transition, but it is also capable of removing the pretransition above a critical concentration. It has previously been shown that alcohols have a biphasic effect on the main transition temperature of phosphatidylcholines (Rowe, E.S. (1983) Biochemistry 22, 3299-3305). At high alcohol concentrations, the main transition is not thermodynamically reversible (Rowe, E.S. (1985) Biochim. Biophys. Acta 813, 321-330). Recently, Simon and McIntosh (Biochim. Biophys. Acta (1984) 773, 169-172) have identified that at high ethanol concentration DPPC exists in the interdigitated phase. The critical ligand concentration at which the pretransition disappears coincides with the induction of main transition hysteresis and the biphasic alcohol effect in the main transition. These three effects appear to correlate with the induction of the interdigitated gel state by alcohols and glycerol. 相似文献
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