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A zoological expedition was made from March to June, 1975, in Northeastern Yunnan at Southeast of Yangtze River (27°30′—28°40′ N., 103°15′—104°25′E.). 450 specimens of birds were collected. Orders and families treated in this paper are listed below:  相似文献   

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The temperature coefficient of the action of β-rays from radium upon the egg of Nereis lies between 1.1 and 1.2. This is of a magnitude characteristic of photochemical reactions.  相似文献   

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ReviseddiagnoaisCraniumcompressedanteroposteriorlyandhighvertical1y.Superiortuskslargeandstraight,nolowerincisors'Ridge-platesprogressiveIymulti-plyingfromsixtoelevenintheintermediateteeth,fromninetofifteenandhaIfilltheposteriormolars.Thereisamediancleftoritsvestigesintheanteriorridge-platesoftheprimitivespecies.Conesrapidlysubdividingbybinaryorternary.fissionintomultipleconelets(8-l2).Ridge-plateselevatingfrombrachyodonttosubhypsodont.Cementdevelopingintheval1eys.RemarksSarwar(l977)propose…  相似文献   

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Contrast sensitivity function(CSF or Tcs)of the visual system is generally regarded to be linearlyrelated to the product of optic MTF of the eye,Te,and MTF of the retina-brain system Trb,  相似文献   

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There seems to be no reasonable doubt that the lungs in a newborn expand progressively during the first few days of life. Some degree of atelectasis seems to be perfectly normal. This is indicated by a number of roentgenographic studies (including those here reported); by the reported findings of pathologists; by the fact that in experimental animals the lungs inflated very unevenly; and by the fact that aeration of only a portion of the lung is needed for complete oxygenation of the blood. The relation of atelectasis to neonatal death is not entirely clear and is probably not always the same. The infant may die from other causes before the lungs are fully expanded. Atelectasis may develop secondarily to other debilitating conditions. The frequent coincidence of prematurity and extensive atelectasis is impressive. It may be that the lungs are so incompletely formed that they cannot expand. On the other hand, atelectasis and massive collapse in the adult is a serious condition and there seems to be no good reason to suppose that this cannot also occur in infants and be serious per se.The air pressures found necessary to expand the lungs in rabbit fetuses were found to be about ten times what adult humans use in quiet respiration and were of about the same magnitude as the pressures found necessary to expand the lungs of stillborn humans. An attempt to produce atelectasis in newborn rabbits by chilling was most inconclusive. Atelectasis did develop in three of 15 animals used in the experiment, but the relation to chilling was not at all clear.  相似文献   

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《生理学报》1999,51(4):2
本工作研究了去细胞外钙对取自9天来亨鸡胚的培养肌管磷脂酰肌醇水解的影响。80 mmol/L K  相似文献   

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