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141.
Thirty uniformly prepared, disarticulated complete skeletons of adultLoris tardigradus lydekkerianus andNycticebus coucang have been weighed for preliminary study of the weight relations between different major skeletal parts. In these forms, combined relative weight of the precaudal vertebrae, ribs and sternum surpasses the averages for the rest of the skeletal parts. The weight of the skull equals one-fifth of the total skeletal weight inLoris andNycticebus. The weight of the skeletons of the limbs (including the shoulder girdle and the hip bones) contributes less than half of the total skeletal weight in lorises. The bones of the upper limbs are lighter than those of the lower limbs in the 2 series examined.Loris andNycticebus are distinguished by having the proportionately heaviest axial skeleton and skull and the lowest relative weights of the bones of the 4 limbs. The combined relative skeletal weight of the upper and lower limbs ranges between 45.34 and 50.01 inLoris andNycticebus. The relative weight of the skeletons of the hands and feet are almost similar to the corresponding weights in the 2 series.As far as the weights of the different skeletal parts are concerned, there is no relative asymmetry in the 2 series ofLoris andNycticebus examined. 相似文献
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Labelling of the catalytic site of lysozyme 总被引:1,自引:0,他引:1
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Over a 12-month period four patients developed acute renal failure after undergoing radiological investigations using contrast media. Though the incidence of serious complications is low, the possibility of adverse side effects must be weighed against the usefulness of the information provided by these techniques. 相似文献
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Summary In a population of Allium stracheyi
Baker (2n=14) growing in Darjeeling both diploids and polyploids occur. The diploids contain B-chromosomes varying from 2–10 in number. Polyploids are conspicuous by absence of B-chromosomes. These in diploids are found in the pollen mother cells and also in the pollen, and some are provided with subterminal constriction.Diploid individuals when brought from Darjeeling to Calcutta (i. e. from temperate to tropical regions) became polyploid within a month and the B-chromosomes were simultaneously lost. In order to confirm this unexpected result, the transfer experiment has been repeated thrice with fresh collections in each case and selection of diploid bulbs after cytological observation. In all cases the result has been the same. In rare cases one or two B-chromosomes were found in the polyploid cells which might represent intermediate steps of the disappearance.B-chromosomes in diploids possibly help the individual to compete with polyploids by enlarging the adaptive capacity.The sudden polyploidisation by transfer from the mountains to the plains might have been the result of a shock due to the temperature difference. The high temperature may be deleterious for the reproduction of B-chromosomes, and their degeneration products possibly contribute to cytoplasmic changes and the spindle disturbances which effect polyploidisation. 相似文献
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