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971.
结合天津师范大学影视艺术学院的实际情况,阐述了影视艺术课程辅助教学系统在辅助教学方面及学生能力培养方面的重要作用。 相似文献
972.
Myb DNA binding inhibited by phosphorylation at a site deleted during oncogenic activation 总被引:65,自引:0,他引:65
The c-Myb nuclear oncoprotein is phosphorylated in vitro and in vivo at an N-terminal site near its DNA-binding domain by casein kinase II (CK-II) or a CK-II-like activity. This in vitro phosphorylation reversibly inhibits the sequence-specific binding of c-Myb to DNA. The site of this phosphorylation is deleted in nearly all oncogenically activated Myb proteins, resulting in DNA-binding that is independent of CK-II. Because CK-II activity is modulated by growth factors, loss of the site could uncouple c-Myb from its normal physiological regulator. 相似文献
973.
A parallel algorithm for real-time computation of optical flow 总被引:2,自引:0,他引:2
The precise management of two-dimensional field of velocities from time-varying two-dimensional images is impossible in general. It is, however, possible to compute suitable 'optical flows' that are qualitatively similar to the velocity field in most cases. We describe a simple, parallel algorithm that computes an optical flow from sequences of real images, which is consistent with human psychophysics and suggests plausible physiological models. In particular, our algorithm runs on a Connection Machine supercomputer in close-to-real time. It shows several of the same 'illusions' that are perceived by humans. A natural physiological implementation of the model is consistent with data from cortical areas V1 and MT. 相似文献
974.
Live Tetrahymena cells bound 3H-diazepam specifically, as demonstrated by autoradiographic evidence of displacement of about 25% of labeled diazepam in the presence of a 1000-fold amount of cold diazepam. The 3H-diazepam bound to membrane preparations isolated from untreated (control) cells was not displaced by cold diazepam, whereas cells involved in primary interaction (imprinting) with diazepam showed amplification and specificity of diazepam binding in both in vivo (cell suspension) and in vitro (pellicle) systems, as well as displacement of bound label in the presence of 1000-fold cold diazepam. It appears that diazepam induced imprinting and, consequently, also the formation of specific receptors in Tetrahymena. 相似文献
975.
976.
Summary In isolated guinea-pig atria, the-adrenolytic isomerd(–)INPEA provoked a stronger prolongation of the refractory period (rp) than did the inactivel(+) isomer. The-adrenolytic drug MJ 1999 prolonged likewise the rp, although it caused no unspecific effect, i.e. an inhibition of contractile force. These observations lead to the conclusion that not only the unspecific local anaesthetic but also the specific-adrenolytic effect is of importance for the prolongation of rp. 相似文献
977.
O. Öztürkcan G. de Saint Blanquat R. Derache 《Cellular and molecular life sciences : CMLS》1973,29(7):811-812
Summary Effects of ether, nembutal or urethane anaesthesia on gastric secretion and mucosal blood flow (MBF) are studied in the Rat; these 3 anaesthetics alter neither volume nor total acidity of juice, but free acidity and proteolytic activity are more importance after ether anaesthesia; MBF is highest in nembutal anaesthetized rats; therefore nembutal is the best anaesthetic for studies of digestive physiology or pharmacology. 相似文献
978.
Deamino1-phenylalanine2-arginine8-vasopressin: A peptide with highly selective antidiuretic activity
E. Stürmer R. L. Huguenin R. A. Boissonnas B. Berde 《Cellular and molecular life sciences : CMLS》1965,21(10):583-585
Zusammenfassung Deamino1-Phenylalanin2-Arginin8-Vasopressin, dessen Synthese und pharmakologische Haupteigenschaften beschrieben werden, zeichnet sich durch eine hohe antidiuretische Wirkung aus. Dieser Effekt ist demjenigen des menschlichen antidiuretischen Hormons qualitativ ähnlich, jedoch wesentlich selektiver. 相似文献
979.
980.