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排序方式: 共有677条查询结果,搜索用时 312 毫秒
671.
672.
The amino acid sequence of the myoglobin of the South American Night Monkey, Aotes trivirgatus, is identical to that of the marmoset (Callithrix jacchus [1]) except for residue 21 which is isoleucine in the marmoset, like in all other anthropoids, but valine in Aotes. Analysis of a possible pathway of the evolution of Aotes myoglobin using 18 known primate myoglobin sequences [2–5] supports the classification of the Night Monkey within Anthropoidea and Platyrrhini but it indicates that this species might be more closely related to the marmoset (family Callitrichidae) than to the family Cebidae as a member of which it is commonly classified. 相似文献
673.
674.
E. J. Hunt U. Kuhlmann A. Sheppard T.-K. Qin B. I. P. Barratt L. Harrison P. G. Mason D. Parker R. V. Flanders & J. Goolsby 《Journal of Applied Entomology》2008,132(2):89-123
Europe lags far behind Australia, New Zealand, Canada and the USA in terms of implementing regulatory procedures for the import and release of invertebrate biological control agents (IBCAs). A number of standards, documents and guidelines have been produced over recent years in an attempt to harmonize regulation of IBCA introduction into Europe. Despite these efforts, the number of member countries implementing any form of IBCA regulation remains low, with many industries, biological practitioners and regulators fearing that a regulatory system would render the process of approval for IBCA introduction into a country costly and time consuming. Europe’s priority is therefore to formulate a regulatory system that will be readily approved of and adopted by all member countries. In this paper we review the current regulatory processes operating in Australia, New Zealand, Canada and the USA. There is potential for Europe to benefit from the years of experience that these countries have in IBCA regulation. We therefore propose recommendations based on features of the regulatory processes in each of the four countries that work well and that could be adopted to generate a workable Europe‐wide regulatory system. 相似文献
675.
Alfred J. Lewy Saeeduddin Ahmed Jeanne Latham Jackson Robert L. Sack 《Chronobiology international》1992,9(5):380-392
A physiological dose of orally administered melatonin shifts circadian rhythms in humans according to a phase-response curve (PRC) that is nearly opposite in phase with the PRCs for light exposure: melatonin delays circadian rhythms when administered in the morning and advances them when administered in the afternoon or early evening. The human melatonin PRC provides critical information for using melatonin to treat circadian phase sleep and mood disorders, as well as maladaptation to shift work and transmeridional air travel. The human melatonin PRC also provides the strongest evidence to date for a function of endogenous melatonin and its suppression by light in augmenting entrainment of circadian rhythms by the light-dark cycle. 相似文献
676.
Philippe Nicol Raymond Vienet Gerard Jourdan Cathy Dumas Fatima Abou El Fadil Henri Benech Jean-Marc Grognet Thierry Tarrade Danielle Pansu Monique Descroix-Vagne 《Peptides》1995,16(8)
The C-terminal heptapeptide-amide (C7-sorbin) is the minimal biologically active fragment of sorbin inducing an increase in intestinal hydroelectrolytic absorption. An analogue (D7-sorbin), characterized by the replacement of the ultimate C-terminal amino acid
-alanine-amide by
-alanine-amide, was synthetized. For pharmacokinetic studies, D7-sorbin and C7-sorbin were tritium labeled. After IV injection, clearances were 10.6 and 30.2 ml−1 for D7-sorbin and C7-sorbin, respectively, and MRT were 34 and 18 min. After SC administration, Cmax attained 0.41% and 0.12% of the dose/ml, respectively. The IP route showed a 45-min delay before Cmax and a 100% bioavailability for both peptides. D7-sorbin was principally excreted in urine, as shown by balance study, and in part in intact form, as controlled by mass spectrometry. D7-sorbin induced a significant decrease of the VIP-induced ileal secretion, previously observed with C7-sorbin. The change of
-Ala to
-Ala increased the stability of the synthetic C-terminal peptide of sorbin whereas its biological activity, bioavailability, and route of elimination were unchanged. 相似文献
677.
Masaki Tomonaga 《Primates; journal of primatology》1993,34(2):161-168
During a visual search performance by a chimpanzee (Pan troglodytes), horizontal location (column) of target was sequentially changed across 48-trial blocks. Reaction time was used for measure
of facilitatory and inhibitory effects of the blocked-trial fixation on her search performance. The chimpanzee showed significant
decrease of response time in the later phase of each block in comparison with the condition in which the target location was
changed to another column than before changing. Furthermore, difference in response time before and after changing column
monotonically and linearly increased as a function of distance between columns. In summary, the blocked-trial fixation of
the target location facilitated the chimpanzee's visual-search performance, and that when the pretrial information became
invalid, her performance was clearly disrupted. Pretrial information about target location could “prime” and modify the chimpanzee's
search strategy. 相似文献