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81.
82.
S Kwon RA Hess D Bunick H Nitta L Janulis Y Osawa JM Bahr 《Canadian Metallurgical Quarterly》1995,53(6):1259-1264
We recently found that cytochrome P450 aromatase (P450arom) is present in germ cells of the mammalian testis and is capable of converting androgens to estrogens in the male reproductive tract. The objective of the present study was to determine whether testicular germ cells and epididymal sperm of an avian species are also capable of synthesizing estrogen. P450arom was localized in the rooster testis and epididymal region by immunocytochemistry, using an antiserum generated against purified human placental cytochrome P450arom. Immunostaining was present in pachytene spermatocytes, round spermatids, elongated spermatids, flagella of late spermatids, and sperm in the epididymal region. A positive reaction was also found in nonciliated cells of the epididymal region. However, the absence of mRNA for P450arom in the epididymal region indicated that the immunoreactive protein present in the epididymal region is not synthesized in this region. The immunoreactive P450arom found in epididymal sperm was shown to be active through use of a 3H2O assay. On the basis of these data, we conclude that rooster testicular germ cells and epididymal sperm are sites for the synthesis of estrogen, a potential regulator or modulator of germinal epithelium in the testis and the epithelium of the epididymal region of the avian species. 相似文献
83.
Although increasing feedback specificity is generally beneficial for immediate performance, it can undermine certain aspects of the learning needed for later, more independent performance. The results of the present transfer experiment demonstrate that the effects of increasing feedback specificity on learning depended on what was to be learned, and these effects were partially mediated through the opportunities to learn how to respond to different task conditions during practice. More specific feedback was beneficial for learning how to respond to good performance and detrimental for learning how to respond to poor performance. The former relationship was partially mediated by feedback specificity's effect on learning opportunities during practice. The results have implications for designing feedback interventions and training to maximize the learning of various aspects of a task. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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A dynamic investigation was done of the immunologic status in 75 patients with purulent surgical lesions of soft tissues. Applied in the complex of therapeutic measures was intracorporeal irradiation of blood with ultraviolet light under control of partial pressure of oxygen and carbon dioxide. The above irradiation was found out to make for a more rapid and marked stabilization of bodily immunologic status. 相似文献
86.
Antisera made against whole cells of Bordetella avium protected turkeys against disease signs of turkey coryza, but antiserum against the dermonecrotic heat-labile toxin (DHLT) did not. Neither antiserum against whole cells nor antiserum against DHLT protected turkeys against colonization of the trachea by B. avium. At least 25 bands in whole cell lysate of B. avium separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) reacted in immunoblots with protective antiserum. These bands occurred at < 40 kDa and > 105.3 kDa. DHLT had an isoelectric point (pI) in the range pH 6.3-6.7. Following SDS-PAGE of isoelectric-focused fractions, two bands were recognized by anti-DHLT with immunoblots of pI 6.3, pI 6.5, and pI 6.7 fractions separated by SDS-PAGE. 相似文献
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Jackson T.J. Engman E.T. Le Vine D. Schmugge T.J. Lang R. Wood E. Teng W. 《Geoscience and Remote Sensing, IEEE Transactions on》1994,32(1):201-206
MACHYDR0'90 was an experiment conducted in Pennsylvania in 1990 to study the synergistic use of remote sensors in multitemporal hydrologic studies. As part of this mission the pushbroom microwave radiometer was flown and used to produce brightness temperature maps. Verification studies and vegetation algorithms for mixed land cover areas are described 相似文献
90.
YT van der Schouw WA van den Beld GA van der Sanden RA Binkhorst FJ Gabre?ls AL Verbeek 《Canadian Metallurgical Quarterly》1993,35(7):608-613
The authors conducted an assessment study of newly developed motor performance items for the diagnosis of myopathy. 17 children who had had muscle biopsy for this diagnosis in the recent past were administered 14 items based on the measurement of static, dynamic and explosive muscle strength and muscle endurance. Individual items did not have perfect discriminative power, but the results were encouraging enough to warrant detailed study with combinations of the items, so that in future fewer children will have to undergo unnecessary muscle biopsies. 相似文献