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131.
132.
AIM:To investigate the effect of high concentration of chlorine gas(Cl2) exposure on lung haemodynamic and respiratory function in intact and isolated perfused rabbit lungs (IPLs). METHODS:8 intact and 10 IPLs were exposed to Cl2 at high concentration(50×10-4)for 20 min, as measured group, 8 additional intact and 9 IPLs, which were similarly treated but not exposed to Cl2, served as controls. The changes of lung weigh of IPL(△W)、pressure of pulmonary artery(Pa)and venous pressure(Pv)、airway pressure and tidal volume(TV) were continuously measured and recorded simultaneously. RESULTS: In IPL group: While the perfusing blood flow was kept constant (133.3 mL/min), and Pv did not change, following the exposure, the Pa increased slightly, then the lung weight were increased significantly and the TV decreased . Hematocrit of perfusate of EIPL and parameters of lung water increased also. In intact group: Pa increased slightly, respiratory rate accelerated immediately, and TV decreased. CONCLUSION:Although mean Pa increased continuously and slightly in both intact and IPL group following the exposure to high concentration of Cl2, the primary cause of edema was most likely to alter pulmonary capillary permeability. The respiratory rate accelerated and TV decreased due to exposure to Cl2 enhanced hypoxia of intact rabbits. 相似文献
133.
通过对 1 2根承受集中荷载作用下破坏后补好的矩形截面钢筋混凝土约束梁斜向贴 CFRP抗剪加固试验结果的分析 ,提出了 CFRP有效应变的概念 ,得出了随角度变化 CFRP抗剪承载力计算公式 相似文献
134.
探讨了在框剪结构中剪力墙的厚度、数量及长度的确定,从剪力墙的平面、竖向布置方面,阐述了剪力墙的布置。 相似文献
135.
徐红霞 《中南林业科技大学学报(自然科学版)》2004,24(6):36-41
信用是现代市场经济的基石,市场经济就是信用经济的理念获得广泛认同.当前我国社会的信用危机已成为制约我国市场经济深入发展的重要因素.信用权是一种独立的人格权,通过民法典构建完整的信用权制度,有助于完善社会信用体系并促进我国市场经济的健康发展.我国应在未来民法典上确立信用权的独立人格权地位并给予直接保护,不断完善信用权制度. 相似文献
136.
Paul Christou 《Euphytica》1993,74(3):165-185
Summary The absence of variety-independent gene transfer methods for major agronomic species has, until now, limited the usefulness of recombinant DNA techniques to crop improvement programs. Until recently, only Solanaceous crops could be used to study fundamental and applied problems in plant sciences. During the past five years rapid advances in cell biology, in combination with the development of novel gene transfer methodology allowed utilization of the tools of plant molecular biology in conventional breeding programs. Cereal and leguminous species were considered to be recalcitrant to genetic manipulation. As a result of the development of direct DNA transfer methodology into organized tissue, we are now in a position to introduce any foreign gene into almost all of the major cereals and legumes. This can be achieved efficiently, often in a variety-independent fashion. The object of this review is to provide a comprehensive account of the state of the art in gene transfer for the cultivated leguminous crops. Important oilseed and feed species primarily in industrialized countries, as well as minor but equally important species for sustaining growth populations in developing countries will be examined. Advantages of the various gene transfer methods that were shown to be useful for specific crops, as well as limitations and problems associated with each crop and gene transfer method will be discussed. Data from field trials of transgenic legumes, where available, will be presented. 相似文献
137.
Gisela Bugge 《Plant Breeding》1987,98(2):149-155
Components of seed yield were estimated for each set of 100 plants derived from six varieties of Lolium perenne. Significant differences between the varieties were found for all components of seed yield, but the range was broader within each variety. An indirect selection of seed yield using the character seeds per spike produced a selection response similar to that obtained by direct selection on high seed yield per plant. A direct and indirect selection of characters estimated in small, drilled plots of topcross off-springs (F1) was less successful than the selection based on the single plants. Spearman rank correlation coefficients between the single plants and their offsprings did not show significant agreement for seed yield. But altogether the results indicated that the increase of seed yield/area was about 6 % when 10 % of the best plants were selected. 相似文献
138.
Summary Starting with two heterogeneous F2 populations, each based on 20 cross combinations, different selection procedures were applied for four consecutive selection cycles. Three of the selection procedures involved seed yield per plant (SYP): (i) direct selection for SYP (DSY); (ii) indexselection for SYP (ISY) with plant length, the ratio of the vegetative top to plant length, end of grain filling and duration of the generative stage as auxiliary characters and finally; (iii) independent culling levels selection (ICL) for the index described above and crude protein content. For ICL-selection the attention is focussed on SYP in this paper.For all three selection procedures, predicted and realized responses were calculated and expressed as percentage of a corresponding non-selected population. The intensities of selection differed over selection methods and generations, mostly due to practical constraints.As far as predicted responses are concerned, ISY-selection seemed to be slightly superior to DSY-selection and DSY-selection to ICL-selection. This order may partly be due to differences in selection intensity. However, none of the predictions was very accurate, but the predictions of ICL-selection seemed to be the most accurate. This has been ascribed also to the relative mild selection intensity applied in ICL-selection. It is concluded that a decision in favour of a complicated selection procedure like index selection based on predicted responses only cannot be defended. As far as realized responses are concerned, DSY-selection seems to be slightly superior to the other two selection procedures, as it is the only procedure that resulted in a more or less stable positive response to selection.The auxiliary characters, especially plant length, showed a marked correlated response to all three selection procedures. In case of direct selection for SYP this seemed paradoxical with the inefficiency of index selection, but, it may reflect the differences in the genuine genotypic correlations and the estimated genotypic correlations. 相似文献
139.
140.
The prefabricated pile,driven in soft clay,can squeeze the soil laterally in a certain scope around the pile,and the void ratio is reduced significantly;consequently,the shear bearing capacity is raised.But the soil parameter,which is used to estimate the capacity of pile,is reduced according to the soil state before the pile was driven.Then,a certain difference appears when the pile is working.The calculation result usually is partial to conservative.This paper analyzes the squeezing mechanism of the pile using the theory of cylindrical cavities expansion.And a formula,which is used to estimate the increment of shear bearing capacity of soil around the pile when excess pore water pressure from pile driving distributes completely,is presented based on the unique relation between the shear bearing capacity and the density of the soil.This formula can be used to estimate the final ultimate-bearing capacity of the pile.The calculated results by the proposed formula are in good agreement with those of the site measurement. 相似文献