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91.
Laparoscopic sperm recovery from the pouch of Douglas and tubal fimbriae was performed in 64 infertile couples. Spermatozoa were recovered from 16/35 couples investigated after AIH, and from 13/29 couples post coitum. The method of insemination had no effect on the result, which was positive in 45.3% of all couples, although AIH did result in significantly larger numbers of peritoneal spermatozoa. The number of peritoneal spermatozoa did not show any direct correlation with the number inseminated, but there were reductions along the tract of 5.83 (+/- 1.4 s.d.) orders of magnitude for total sperm count, and 5.52 (+/- 1.21 s.d.) for the number of motile spermatozoa. Only sperm motility had a significant influence on the success of sperm transport; spermatozoa were recovered from patients with sperm densities as low as 3.0 and 3.5 x 10(6)/ml, but with 56 and 44% motile spermatozoa. No influence of cycle day within the range +/- 4 days of ovulation on sperm transport was found. In 45 couples, routine semen analyses were apparently completely normal, but the incidence of sperm recovery was still only 49% (22/45), suggesting that a failure of sperm transport may have been a significant causative factor in their infertility.  相似文献   
92.
Pulsed NMR techniques have been applied to the study of the relaxation parameters characterizing 23Na within frog striated muscle. Experiments were performed at 3°C, 22–24°C and 39°C at a Larmor frequency of 15.7 MHz; at 22–24°C, measurements were obtained both at 15.7 MHz and at 7.85 MHz.As previously reported, only a single spine-lattice relaxation time (T1) was observed, but both slow (T2)I and fast (T2)II components of the spin-spin relaxation time were measured. The effect of temperature (θ) upon (1/T1) was qualitatively similar to that reported for 23Na in free solution; (θ) did not significantly affect (1/T2) over the range of temperatures studied. (1/T2)I, and to a lesser degreee, (1/T1) exhibited a modest inverse dependence of doubtful significance on the Larmor frequency.The data are examined within the framework of a simple specific model; a conservative values in assumed for the quadrupolar coupling constant characterizing immobilized intracellular Na+. Within this framework, the results suggest that the fraction of bound ions whose molecular tumbling is severely restricted does not exceed some few percent of the total sodium population.  相似文献   
93.
Genetic map of Saccharomyces cerevisiae, edition 9.   总被引:89,自引:4,他引:85       下载免费PDF全文
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On the occasion of the XIIIth International Symposium on Spermatology held from 9 to 13 May 2018 in Stockholm (Sweden), participants (guest speakers and audience) collectively felt the need to make a public statement on the general issue of male reproductive health. Our intention is to raise awareness of what we believe is a neglected area of research despite alarming situations around the world. The disclosure strategy desired by the co-authors is to bring it to the attention of the greatest number partly by considering co-publication in the various periodicals dealing with Reproductive Biology and Andrology. BaCA’s editorial office accepted this mission and found it natural that our periodical, the official journal of the French Andrology Society (SALF), should carry this message.  相似文献   
96.
Through use of tetrad, random spore, trisomic, and mitotic analysis procedures a large number of genes, including 48 new genetic markers, were studied for their locations on the genetic maps of the yeast Saccharomyces cerevisiae. Eighteen new centromere linked genes were discovered and all but one was located on various ones of the 16 previously-established chromosomes. Five fragments of linked genes were also assigned to chromosomes; four were located on known chromosomes while the fifth determined one arm of a new chromosome. The experiments indicate that seventeen is likely to be the haploid chromosome number in this yeast. Most chromosomes have been established by genetic means to be metacentric and their genetic lengths vary from 5 cM to approximately 400 cM. Functionally-related sets of genes generally were found to be dispersed over the genome.  相似文献   
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The mating reaction in Saccharomycopsis lipolytica is shown to be bipolar through the analysis of whole meiotic tetrads. Genetic evidence is provided that alkane metabolism proceeds through a fatty acid or a fatty acid intermediate since several mutants unable to grow on n-tetradecane were also unable to utilize palmitic acid.  相似文献   
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