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41.
In this essay we provide an interdisciplinary approach to the problem of the evolution of human cognition and suggest the theoretical framework of genetic system theory (GST) for organizing the relevant content of several disciplines. This bio-social-cultural theory is based on the assumption that organisms are dynamic systems which interact with one another and their environment and are themselves composed of dynamic internal relations at several levels. Special emphasis will be placed upon these internal cellular and molecular mechanisms underlying the physiological mechanisms of learning and memory. The human individual organism is emphasized because in its experiential activity over time it is the site of integration for social, and cultural stimuli and because of its unique properties among living things. The primary disciplines for our discussion are drawn from the biological, social, and humanistic sciences and several concrete examples are given from each science. 相似文献
42.
二十一世纪以来都市圈快速扩张对区域社会-生态系统的可持续发展构成威胁,基于动态演进视角的区域社会-生态系统运行机制解析备受关注。本文以南京都市圈为例,从区域和城市两个尺度,基于适应性循环理论与PSR框架解析2000-2019年近二十年来都市圈社会-生态系统的交互适应循环阶段,以及每个阶段系统的差异化应激响应机制。研究表明南京都市圈社会-生态系统整体经历了3个适应循环周期,现处于新一轮的适应性循环阶段,系统适应性呈上升趋势,但社会子系统和生态子系统尚未取得协调。都市圈内各城市的社会-生态系统演进类型有所不同,可分为稳定增长型、波动增长型、不均衡发展型和生态危机型四类。未来需要采取差异化的社会-生态系统治理策略,确保都市圈整体优化发展。 相似文献
43.
目的 构建符合广东省医疗卫生现状和特点的医师多点执业实施基本框架。方法 采用Delphi法对备选指标进行3轮专家咨询。结果 预调查和2轮咨询专家积极性系数分别为100%、96.67%、100%;专家的权威系数为0.70;正式两轮咨询一级指标权重权重比例接近,P<0.005 ;正式两轮咨询专家一致性系数分别为0.161、0.191。结合专家对指标评价总分的排序和各指标重要性、可操作性变异系数,最终筛选25个指标。结论 从公立医院的角度,构建了一个较为科学、合理的医师多点执业实施框架。 相似文献
44.
A scientific basis for restoring fish spawning habitat in the St. Clair and Detroit Rivers of the Laurentian Great Lakes 下载免费PDF全文
Edward F. Roseman Gregory Kennedy James C. Boase Jaquelyn M. Craig David H. Bennion Jennifer Read Lynn Vaccaro Justin Chiotti Richard Drouin Rosanne Ellison 《Restoration Ecology》2015,23(2):149-156
Loss of functional habitat in riverine systems is a global fisheries issue. Few studies, however, describe the decision‐making approach taken to abate loss of fish spawning habitat. Numerous habitat restoration efforts are underway and documentation of successful restoration techniques for spawning habitat of desirable fish species in large rivers connecting the Laurentian Great Lakes are reported here. In 2003, to compensate for the loss of fish spawning habitat in the St. Clair and Detroit Rivers that connect the Great Lakes Huron and Erie, an international partnership of state, federal, and academic scientists began restoring fish spawning habitat in both of these rivers. Using an adaptive management approach, we created 1,100 m2 of productive fish spawning habitat near Belle Isle in the Detroit River in 2004; 3,300 m2 of fish spawning habitat near Fighting Island in the Detroit River in 2008; and 4,000 m2 of fish spawning habitat in the Middle Channel of the St. Clair River in 2012. Here, we describe the adaptive‐feedback management approach that we used to guide our decision making during all phases of spawning habitat restoration, including problem identification, team building, hypothesis development, strategy development, prioritization of physical and biological imperatives, project implementation, habitat construction, monitoring of fish use of the constructed spawning habitats, and communication of research results. Numerous scientific and economic lessons learned from 10 years of planning, building, and assessing fish use of these three fish spawning habitat restoration projects are summarized in this article. 相似文献
45.
Charmantier A Buoro M Gimenez O Weimerskirch H 《Journal of evolutionary biology》2011,24(7):1487-1496
Natal dispersal is a key life history trait for the evolution and adaptation of wild populations. Although its evolution has repeatedly been related to the social and environmental context faced by individuals, parent-offspring regressions have also highlighted a possible heritable component. In this study, we explore heritability of natal dispersal, at the scale of the sub-Antarctic Possession Island, for a large-scale foraging seabird, the Wandering albatross Diomedea exulans, exploiting a pedigree spanning over four decades and a maximum of four generations. The comparison of three different methods shows that heritability on the liability scale can vary drastically depending on the type of model (heritability from 6% to 86%), with a notable underestimation by restricted maximum likelihood animal models (6%) compared to Bayesian animal models (36%). In all cases, however, our results point to significant additive genetic variance in the individual propensity to disperse, after controlling for substantial effects of sex and natal colony. These results reveal promising evolutionary potential for short-scale natal dispersal, which could play a critical role for the long-term persistence of this species on the long run. 相似文献
46.
Foraging theory has typically been concerned with the acquisition of a single resource even though organisms from mammals to protozoa are capable of balancing their requirements for multiple resources. Existing theory concerning multiple nutrients from multiple foods does not predict the sequence of food selection. We constructed an optimisation model of the simplest case of two foods containing differing amounts of two nutrients. We begin with the well-supported assumption that reproductive value declines with the distance from target nutrient intake. We show that nutrient space divides into two distinct areas where the animal should exclusively consume one food or the other. The organism thus initially concentrates on one food type until the border between the areas is reached and then moves as closely as possible along the border to approach the target. This strategy is commonly observed in a range of organisms, suggesting that the assumed fitness function is common. 相似文献
47.
It is widely assumed that terrestrial food webs are built on a nitrogen-limited base and consequently herbivores must compensate through selection of high-protein foods and efficient nitrogen retention. Like many folivorous primates, gorillas' diet selection supports this assumption, as they apparently prefer protein-rich foods. Our study of mountain gorillas (Gorilla beringei) in Uganda revealed that, in some periods, carbohydrate-rich fruits displace a large portion of protein-rich leaves in their diet. We show that non-protein energy (NPE) intake was invariant throughout the year, whereas protein intake was substantially higher when leaves were the major portion of the diet. This pattern of macronutrient intake suggests that gorillas prioritize NPE and, to achieve this when leaves are the major dietary item, they over-eat protein. The concentrations of protein consumed in relation to energy when leaves were the major portion of the diet were close to the maximum recommended for humans and similar to high-protein human weight-loss diets. By contrast, the concentrations of protein in relation to energy when gorillas ate fruit-dominated diets were similar to those recommended for humans. Our results question the generality of nitrogen limitation in terrestrial herbivores and provide a fascinating contrast with human macronutrient intake. 相似文献
48.
Two novel metal-organic hybrid coordination polymers {[Cu(bpo)(chdc)(H2O)](H2O)0.5}n (1) and [Pb(chdc)(H2O)]n (2) have been synthesized under different conditions and structurally characterized by single-crystal X-ray diffraction technique, where H2chdc refers to a flexible 1,4-cyclohexanedicarboxylic acid ligand and bpo is 2,5-bis(4-pyridyl)-1,3,4-oxadiazole. Complex 1 has a two-dimensional (2-D) grid-like [11.28 × 13.63 Å2] framework in which the CuII centers are extended via bidentate bridging ligands bpo and e,e-trans-chdc along two directions, exhibiting large porous cavities. Coordination polymer 2 represents the first PbII complex of H2chdc in which the larger PbII centers are connected by e,a-cis-chdc anions to afford a 2-D close-knit structure. 相似文献
49.
Restructuring and Health in Canadian Coastal Communities 总被引:1,自引:0,他引:1
A.?Holly?DolanEmail author Martin?Taylor Barbara?Neis Rosemary?Ommer John?Eyles David?Schneider Bill?Montevecchi 《EcoHealth》2005,2(3):195-208
Environmental and socioeconomic restructuring has had profound consequences for coastal communities in Canada. The decline of traditional resource-based industries—fisheries, forestry, and mining—and the emergence of new economic activities, such as tourism and aquaculture, compounded by concurrent shifts in social programs, have affected the health of environments, communities, and people. Drawing on research conducted as part of the interdisciplinary major collaborative research initiative Coasts Under Stress, we examined the implications of interactive restructuring for the health of people and communities on Canada’s east and west coasts. The research is guided by a socioecological framework that identifies the pathways from interactive restructuring through health determinants to health risks and health outcomes. The utility of the proposed framework is exemplified by a specific place-based example in Prince Rupert, British Columbia, and a case-based example from coastal communities in Newfoundland and Labrador. A focus on interactive restructuring draws our attention to the many challenges associated with promoting health in a context of rapid and often accelerating environmental and institutional change that is relevant to other areas and contexts. 相似文献
50.
Self-assembly reaction of Cd(ClO4)2 · 6H2O with Norfloxacin (H-Norf) affords a novel 2D rectangular grid framework [Cd(Norf)(ClO4)(H2O)] (1) with strong blue luminescent emission (λem=425 nm), while Norf− acts as a tetradentate bridging linker to connect three Cd centers and ClO4 − completes Cd center octahedron coordination geometry. The compound 1 has crystallographic data of triclinic, space group , a=9.4577(1) Å, b=9.5012(2) Å, c=12.2805(1) Å, V=3624.4(3) Å3, Z=2. 相似文献