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491.
瑞典国家财产委员会拥有骑士岛的所有权与管理权,并计划对该岛上所有的公共空间进行更新和开发,以提高其可达性与吸引力。该项目的核心是找到一种更新和修复岛屿的方法,从而在尊重历史价值的同时满足现代功能需求。对骑士岛南部的改造是岛上公共空间更新的第一部分。设计的关键条件是沿滨水区域创造可以供人步行与停坐的大面积空间,并在保持开放海港氛围的同时,对旧的道路铺装进行管理。设计者设计了一套灵活使用公共空间的综合解决方案,将开放空间与之前的码头一样,沿着水滨的形态进行布局。 相似文献
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Melinda L. Moir Karl E. C. Brennan Jonathan D. Majer John M. Koch Murray J. Fletcher 《Restoration Ecology》2010,18(Z1):136-147
Restoring disturbed lands is essential for conserving biodiversity. In floristically diverse regions, restoring all plant species following anthropogenic disturbance is financially costly and it is unknown if this can be achieved. However, re‐creating faunal habitat may not require reinstating all plant species if there is a high degree of redundancy. Here, we assess whether there is redundancy among a subset of native plant species chosen to restore fauna habitat following a severe disturbance. Additionally, we determine if reestablished plants support similar faunal assemblages as the same plant species in less disturbed forest. We sampled plant‐dwelling Hemiptera from 1,800 plants across 16 species. We found 190 species of Hemiptera, with most plant species in the forest having distinct hemipteran assemblages. Returning these plant species to areas undergoing restoration reinstated 145 hemipteran species, including the dominant species. Recalcitrant plant species (difficult to propagate and reestablish in restored areas) had different hemipteran assemblages from all other species. There was only one plant species that did not have a distinct assemblage and thus was considered redundant. We conclude that there is little redundancy in this study. For plant‐dwelling Hemiptera (with good powers of dispersal) to recolonize restored areas, restoration efforts will need to reinstate at least 13 of the 16 species of host plant of appropriate age and structure. Consequently, to meet the goal of restoring fauna habitat when there is no knowledge of which plant species are redundant, restoration projects should aim to reinstate all plant species present in less disturbed reference areas. 相似文献
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Sulfur pools in the rumen and sulfur flows from the rumen were investigated in two experiments with sheep on a diet containing equal parts of oaten and lucerne chaffs. The diet was fed at two levels, either chopped or pelleted, and with intraruminal DL-methionine supplements. Ruminal fluid volumes and fluid flows to the omasum were measured. None of the treatments influenced ruminal fluid volume. Fluid flow to the omasum, however, was increased by increasing dry matter intake (DMI), and was further enhanced by feeding chaffed hay rather than the same materials ground and pelleted; the DL-methionine supplement had no effect. First approximation of the ruminal sulfur pools and of sulfur flows to the omasum were derived from the concentration of sulfur in true digesta and the ruminal fluid volume or fluid flow. Increasing DMI from 500 to 1000 g/day resulted in larger ruminal pools of total (1096 v. 792 mg), neutral (1016 v. 731 mg) and protein (479 v. 419 mg) sulfur, but the reducible sulfur pools were not affected by the level of DMI. Infusions of DL-methionine increased the ruminal sulfide sulfur pool irrespective of level of DMI. The first approximation of total sulfur flow was increased by 1660 mg/day at the higher level of DMI, due mainly to increases of 710 mg S/day as protein sulfur and 859 mg S/day as non-protein neutral sulfur. Flows of inorganic sulfate and ester sulfate sulfur, although small in comparison with organic sulfur flows, increased with level of DMI. Sulfide sulfur flows were also increased at the higher level of DMI, and were almost doubled by intraruminal infusions of DL-methionine. 相似文献
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The metabolism of dietary and supplemental DL-methionine sulfur in the stomach of sheep was studied in two experiments. In both experiments sheep were fed a 50 : 50 oaten chaff: lucerne chaff ration at two levels of intake, and some animals received intraruminal infusions of DL-methionine. In experiment 2 increasing dry matter intake (DMI) increased first approximations of total, neutral, protein and reducible sulfur flows and also sulfide sulfur flow from the reticulo-rumen. Increased DMI (from 500 to 1000 g/day) also resulted in greater true flows of total (2207 v. 1104 mg/day), neutral (1867 v. 1043 mg/day) and protein (893 v. 482 mg/day) sulfur at the duodenum. Two flow diagrams of sulfur metabolism in the compartments of the ruminant stomach were developed from the data of experiment 2. Fluid flows of sulfur in experiment 1 were used to supplement the data of experiment 2 in developing the balance models. The two models represent the extremes of dietary and supplemental sulfur metabolism in the sheep's stomach under the conditions of experiment 2, and they are discussed in relation to previous research on sulfur metabolism in the stomach. 相似文献