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11.
Intracellular polyamine levels in ejaculated spermatozoa and seminal fluid from rams were determined by fluorescent spectroscopy of their dansyl derivatives. Relationships between the sperm polyamine content and sperm motility of six mature and eight pubescent rams were studied. Samples were collected from both groups once a month from August through October. Mature rams had a greater percentage of motile sperm cells than lambs (94% versus 73% in September and 92% versus 78% in October); higher spermidine content (36 versus 9 pmol/10(8) cells in September and 162 versus 55 pmol/10(8) cells in October); higher spermine content (984 versus 205 pmol/10(8) cells in September and 1,229 versus 414 pmol/10(8) cells in October); and higher total sperm polyamine content (1,021 versus 216 pmol/10(8) cells in September and 2,258 versus 973 pmol/10(8) cells in October). In the lambs, spermidine content increased (55 versus 9 pmol/10(8) cells); spermine content increased (414 versus 205 pmol/10(8) cells); and total sperm polyamine content increased (973 versus 215 pmol/10(8) cells) in October compared to September. Ejaculates with sperm motility higher than 85% had greater spermine (848 versus 234 pmol/10(8) cells in September and 1064 versus 449 pmol/10(8) cells in October), and total sperm polyamine content (882 versus 244 pmol/10(8) cells in September and 2,015 versus 1,008 pmol/10(8) cells in October) than ejaculates with less than 450 pmol total sperm polyamines/10(8) cells was 68% +/- 6% compared to 90% +/- 4% in cells with greater than 450 pmol (average for all ejaculates) total sperm polyamines/10(8) cells. These data suggest a positive relationship between sperm polyamine constant and sperm motility.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Oscillatory motion of the normal cervical spinal cord   总被引:2,自引:0,他引:2  
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Periosteal Ewing sarcoma   总被引:3,自引:0,他引:3  
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In a prospective, randomized study of insemination with donor semen, intracervical insemination by straw was compared with insemination using a cervical cap with an intracervical reservoir. A total of 91 patients completed 486 treatment cycles. There were no significant differences in age, parity, indication for insemination by donor, or method of cycle monitoring between women who became pregnant and those who did not conceive with either insemination method. In 236 standard intracervical insemination cycles, 14 patients became pregnant (5.9% per cycle), whereas 38 patients conceived in 250 cervical cap cycles (15.2% per cycle). Both the crude pregnancy rates and the cumulative pregnancy rates calculated by the Kaplan-Meier life-table method were significantly different (chi(2)-test, P < 0.001, and log-rank test, P < 0.005 respectively). Pregnancy rates in artificial insemination with cryopreserved donor semen may be improved by the use of a cervical cap when compared to cervical insemination by straw. The use of the cervical cap may prolong the exposure of the spermatozoa to the cervical mucus and prevent the backflow of semen into the vagina.   相似文献   
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Dumas  JM; Edde  DJ 《Radiology》1986,160(2):453-456
In a prospective study conducted over a 12-month period, 30 patients underwent double-contrast arthrography of the knee followed by arthroscopic study. An 80% correlation rate was found between results. Arthrography had a higher rate of accuracy (93%) than arthroscopy (84%) and had a 7% false-positive and 0% false-negative rate. A commonly overlooked arthrographic sign--the triple-S or stuck sail sign--was 91% accurate in the prediction of meniscal tears. The complementary nature of the two examinations is discussed.  相似文献   
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A new bone graft substitute made by conversion of the calcium carbonate exoskeleton of reef-building sea coral into hydroxyapatite has recently become clinically available. The normal radiographic appearance of two forms of this material is described. In the immediate postoperative period, the exoskeletal architecture of these implants is readily appreciated. With graft incorporation over the ensuing months, their intrinsic structure is gradually lost in association with poor marginal definition. Evolving radiographic findings reflect the biocompatible nature of these implants, which provides the potential for ingrowth of native bone with preservation of the coralline scaffold, resulting in enhanced biomechanical properties.  相似文献   
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