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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
941.
Hill D Correa MT Stevens JB 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1994,23(3):73-75
Azostix-reagent-tests(R) strips (Ames, Miles, Inc., Diagnostic Division, Elkhart, IN) were used to measure blood urea nitrogen values in blood samples from 125 dogs and cats at the North Carolina State University, College of Veterinary Medicine. Results of the tests were compared with standard serum urea nitrogen results. Sensitivity, specificity, and negative predictive values were high (86.4, 90.3, and 96.5%, respectively). Positive predictive value was low, 65.5% of the dogs and cats with elevated blood urea nitrogen values were correctly classified as abnormal The test performs well when the prevalence of abnormal values is near 50%. 相似文献
942.
943.
Wuethrich B 《Science (New York, N.Y.)》1994,265(5180):1802-1803
944.
945.
Seedlings of three families of jack pine (Pinus banksiana Lamb.) were subjected to 16 combinations of photoperiod, growth environment (outdoors, greenhouse and biotron) and gibberellin (GA(4/7)) treatment. After 14 months, which included two dormancy induction periods, ovulate flowering was observed. There was a strong positive correlation between flowering and seedling height; female flower production was stimulated by both a declining photoperiod during bud development and GA(4/7) treatment; and there was an interaction between GA(4/7) treatment and family, such that the difference in flowering intensity between a late-flowering and an early-flowering family was eliminated by GA(4/7) treatment. The results suggest that the genetic control over the time of onset of flowering, and GA(4/7)-induction of flowering depend on a common mechanism. 相似文献
946.
947.
Ordered arrays of charged uniform colloidal polystyrene particles in solution form a single-wavelength laser filter that is transparent to other wavelengths. A usable filter was prepared by solidification within an acrylamide-methylene-bisacrylamide gel. The rejection wavelength of the colloidal array filter changes with gel composition. Cryogenic transmission electron microscopy of two gel formulations shows that the colloidal array filter is composed of AAA stacking of close-packed planes. Excellent agreement is found between the layer spacings measured and those predicted from the rejection wavelengths. 相似文献
948.
949.
Sabel BA 《Science (New York, N.Y.)》1993,260(5115):1753-1758
950.