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21.
Renmei Ren Kanhui Yan Yanjie Su Hanjun Qi Bin Liang Wunyong Bao Frans B. M. de Waal 《Primates; journal of primatology》1991,32(3):321-327
Observations were made following 130 spontaneous aggressive incidents in two small breeding groups of captive golden monkeys
(Rhinopithecus roxellanae roxellanae). Participants were observed both during the first 10 min following these incidents and during matched control observations.
An increased contact rate was observed between opponents following the aggressive incident. Post-conflict contacts were characterized
by a number of behavior patterns: open mouth, rapid grooming, embrace, and crouching. Adult males played an important role
as mediator in agonistic disputes among females: males intervened in 93.6% of female fights. It is speculated that this intervention
behavior is related to the species' organization into one-male units. 相似文献
22.
Genetic mapping of a gene causing hypertension in the stroke-prone spontaneously hypertensive rat. 总被引:47,自引:0,他引:47
H J Jacob K Lindpaintner S E Lincoln K Kusumi R K Bunker Y P Mao D Ganten V J Dzau E S Lander 《Cell》1991,67(1):213-224
The stroke-prone spontaneously hypertensive rat (SHRSP) is a well-characterized model for primary hypertension in humans. High blood pressure in SHRSP shows polygenic inheritance, but none of the loci responsible have previously been identified. To locate genes controlling this quantitative trait, we mapped a large collection of DNA polymorphisms in a cross between SHRSP and the normotensive WKY strain. Here we report strong genetic evidence that a gene, Bp1, having a major effect on blood pressure maps to rat chromosome 10 with a LOD score of 5.10 and is closely linked to the rat gene encoding angiotensin-converting enzyme (ACE), an enzyme that plays a major role in blood pressure homeostasis and is an important target of anti-hypertensive drugs. We also find significant, albeit weaker, linkage to a locus, Bp2, on chromosome 18. We discuss the implications of genetic dissection of quantitative disease-related phenotypes in mammals. 相似文献
23.
Jean-Marc Gilli Paolo Mariani Franco Rustichelli Bin Yang Hervé Delacroix 《Molecular Engineering》1992,2(2):177-188
We recently showed that a side-chain industrial co-oligosiloxane presents a quenchable enlarged blue phase behaviour at the cholesteric-isotropic phase transition. In this paper, we present the results of a structural study based on X-ray diffraction, differential scanning calorimetry and optical measurements. In particular, the smectic A organisation is demonstrated in the lower temperature domain, which was hitherto understood as a cholesteric phase. A structural model for this phase is proposed on the basis of the analysis of the anisotropic scattering of stretched fibers. Our results also suggest that the observed glass transition is indeed a rather complex phenomenon, which seems to involve not only the freezing of the main chains, but also smectic correlations at the side-chain level. Moreover, the calorimetric study indicates that, notwithstanding the conservation of the processed film's optical properties, low kinetic reorganisations occur at room temperature. 相似文献
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S Y Yan Z R Mao H Y Yang M A Tu S H Li G P Huang G S Li L Guo G Q Jin R F He 《The International journal of developmental biology》1991,35(4):429-435
The nucleus of a blastula cell from Tilapia (Oreochromis nilotica, family Cichlidae, order Perciformes) was transplanted into an enucleated egg of Loach (Paramisgurnus dabryanus, family Cobitidae, order Cypriniformes). From among 3747 nucleo-cytoplasmic hybrid (NCH) eggs two NCH larval fish (0.05%) were obtained; one died on the 6th day and the other died on the 12th day after the operation. Morphological examinations showed that both NCH larval fish had developed normally with an opened mouth except they could not take food after complete utilization of their egg yolk on the 5th day of development. The possible mechanisms for obtaining such inter-order NCH larval fish are discussed. This is the first report indicating that inter-order NCH larval fish can be obtained in spite of their evolutionary divergence. 相似文献
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27.
Abidin Bin Hamid John E. Smith 《Journal of industrial microbiology & biotechnology》1987,2(3):137-141
Summary Phenobarbital stimulated aflatoxin biosynthesis byAspergillus flavus and this was paralleled by an increase in microsomal NADPH-cytochromeP-450 reductase and cytochromeP-450 activities. Aflatoxin biosynthesis was inhibited by SKF 525-A, metyrapone and cyanide, inhibitors of the cytochromeP-450 monooxygenase system, further suggesting that aflatoxin biosynthesis byA. flavus could be mediated by a cytochromeP-450 monooxygenase enzyme system. 相似文献
28.
CAM植物按其对环境的反应可分为两种类型:即专一CAM植物和兼性CAM植物。前者不易受外界环境的变化而改变其CAM性质;后者的光合型可随季节和水分胁迫等而发生变化,也可因人工诱导作用而使其由C_3型转变为CAM型。 相似文献
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