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981.
Florencia Luna 《Developing world bioethics》2019,19(2):86-95
“Vulnerability” is a key concept for research ethics and public health ethics. This term can be discussed from either a conceptual or a practical perspective. I previously proposed the metaphor of layers to understand how this concept functions from the conceptual perspective in human research. In this paper I will clarify how my analysis includes other definitions of vulnerability. Then, I will take the practical‐ethical perspective, rejecting the usefulness of taxonomies to analyze vulnerabilities. My proposal specifies two steps and provides a procedural guide to help rank layers. I introduce the notion of cascade vulnerability and outline the dispositional nature of layers of vulnerability to underscore the importance of identifying their stimulus condition. In addition, I identify three kinds of obligations and some strategies to implement them. This strategy outlines the normative force of harmful layers of vulnerability. It offers concrete guidance. It contributes substantial content to the practical sphere but it does not simplify or idealize research subjects, research context or public health challenges. 相似文献
982.
Practitioners of classical biological control of invasive weeds are confronted with a dual expectation: to achieve successful
control of plant invaders and to avoid damage to nontarget plants and adverse indirect effects. In this paper we discuss key
issues that we consider to be crucial for a safe, efficient, and successful classical biological control project, and that
have also caused some recent controversy. These include selection of effective control agents, host specificity of the biological
control agents, implications of the genetic population structure of the target populations, and potential impact on native
food webs. With regard to improving the success rate of biological control of plant invaders, we first emphasize the importance
of a clear a priori definition of success and a more ecosystem-based approach to better document both negative effects of
the invasive plant as well as potential positive and negative effects of introducing biological control agents. Secondly,
pre-release impact assessment could be improved by better focusing on how to reach high densities of the control agents and
by including tolerance to and compensation of herbivory. Thirdly, we advocate a reinforced effort to integrate and combine
biological control in combination with existing or potential management options. Finally, we propose various ecological and
evolutionary hypotheses in the framework of our topic to document that biological control programmes against plant invaders
also offer a great opportunity to gain new insights into basic processes in ecology and evolution. 相似文献
983.
984.
One of the main functions of exploratory behaviour is to gain information about the environment. The adaptive value of such
behaviour should vary with ecological conditions influencing the diversity and stability of resources, as well as with the
costs associated with gathering information. Consequently, predictions can be made about environmental factors influencing
the evolution of exploration. We used comparative methods, combining a field experiment with literature data, to study correlated
evolution between explorative behaviour and ecology among 13 species of Darwin’s finches. Controlling for phylogenetic influences,
we found that exploration (measured as the proportion of individuals responding in the experiment) increased with diet diversity
and the amount of fruit in diet, consistent with theories stating that exploration aimed at finding new food types should
be more beneficial for generalists than for specialists. However, our study is the first to demonstrate a correlation between
neophilia and food diversity. Contrary to our prediction, species with a high percentage of concealed food in their diet were
less explorative. A possible explanation for this novel finding is that in our study system concealed food may be a stable
resource, and species using such resources should be less dependent on the discovery of new food types. 相似文献
985.
By using biofuels bioproductive land is devoted to supply energy. As the bioproductive land area on our planet is confined and actually decreasing, biofuels compete against other demands like the production of food, industrial resources, nature conservation etc. This not only results in higher prices for agricultural and forestry products, but also increases environmental pressures. The aim of this paper is to clarify if and to which extent biofuels might be sustainable by applying modified calculation methods of the ecological footprint. It can be concluded that biofuels can offer huge environmental benefits compared to fossil fuels. Yet, if and to which extent biofuel production is sustainable depends on the amount of land available and, therefore, can only be decided in a regional context. Ecological footprinting can significantly support these regional decision making processes. 相似文献
986.
Erwin Bergmeier Arne Strid 《Botanical journal of the Linnean Society. Linnean Society of London》2014,175(4):607-623
On the basis of extensive field studies throughout Greece and of about 19 500 field and literature records extracted from the Flora Hellenica Database, we provide the first survey of wild plant species of traditional agriculture in Greece (hereafter TA species). For each of the 138 taxa, life form, rareness (on national scale), local abundance (habitat occupancy) and regional restrictedness are given. We infer population trends from the record chronology of the taxa in the Flora Hellenica Database, and we assess the Red List status of the arable plants using IUCN criteria. According to current knowledge, two TA species are presumed Extinct in Greece and seven Critically Endangered. Almost half of the species are threatened, including 46 Vulnerable and 15 Endangered taxa. There is a high proportion of locally distributed taxa among Greek TA species. Distribution patterns show a pronounced south–north gradient, and the unique character of the East Aegean arable flora is revealed. Most arable species are annuals (83%). Perennial herbs, mostly bulbous or tuberous plants (geophytes), account for 17%, and a major proportion of the latter must be considered as threatened at different levels. The chronology of decline of certain TA species is reflected by processes of agricultural intensification and regional urbanization. We suggest conservation measures for the unique arable flora of Greece. To reflect the geographical and ecoregional variation, in situ measures should focus on areas with species‐rich arable fields in all phytogeographical regions of Greece. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 175 , 607–623. 相似文献
987.
Cornus officinalis is a small deciduous tree with significant medicinal values. To explore the ecological effects on phenotypic, cytological and biochemical diversity of medicinal plants, we estimated the loganin content, C-values and fruit and seed phenotypic traits of 80 C. officinalis germplasms collected from across three genuine producing areas of China and Madison, USA. Our results showed that most fruit and seed phenotypic traits of C. officinalis germplasms from Madison, USA were significantly larger than those from China, but the loganin contents and 2C values of germplasms from China (0.9% and 5.92 pg) were significantly higher than those from Madison (0.6% and 5.29 pg) (P < 0.01). These data highlight the fact that there was a tight association between temperature, precipitation and loganin content in C. officinalis. Based on the above results, we found that C. officinalis had a tendency to decline in genome size (GS) and loganin content during the long period of adaptation and evolution with new ecological variables. We are able to presume that the ecological variable is the key factor in determining phenotypic diversity, GS and active ingredient of medicinal plants. 相似文献
988.
下辽河平原景观格局脆弱性及空间关联格局 总被引:13,自引:0,他引:13
以东北三省开发强度最大的辽河中下游地区——下辽河平原为研究对象,根据景观格局脆弱性的概念及内涵,通过景观敏感度指数和景观适应度指数构建景观格局脆弱度指数,并借助地统计学和空间自相关模型分析的理论方法,对下辽河平原景观格局脆弱度的空间分布特征、变异规律以及空间关联格局进行探讨,结果表明:①1989—2010年下辽河平原景观格局脆弱度总体上呈递减趋势;②1989—2010年研究区景观格局脆弱度Moran's I表现为一定程度的正相关,且相关程度略微呈下降趋势;③1989—2010年研究区景观格局脆弱度局部空间自相关和显著性水平均发生了明显的变化;④研究区各时期景观格局脆弱度的空间相关性是受结构性因素和非结构性因素共同影响,C0所占的比例在3a期间有逐步上升趋势,表明非结构性因素对景观格局脆弱度演变的影响程度不断加深,但是结构性因素(地形地貌、水文、土壤植被类型等)仍然对本区景观格局脆弱度的空间分布起决定性作用。 相似文献
989.
《Comptes rendus biologies》2014,337(7-8):480-486
A distinctive new species of ground burrowing tarantula from Western Ghats endemic genus Thrigmopoeus is described from Kerala State, India. Thrigmopoeus psychedelicus sp. nov. differs from putative species of the genus in the adults being black overall with a metallic blue lustre on the carapace and abdomen. Females of Thrigmopoeus psychedelicus sp. nov. exhibit polychromatism. Juveniles and sub-adults are paler with vibrant maroon colouration on its abdomen whereas adult females are much darker and lack vibrant colouration as sub-adults. 相似文献
990.
《Journal for Nature Conservation》2014,22(6):497-503
Although there is high potential for conservation of species outside protected areas, it is often neglected in researches and conservation programs. Protected species are legally protected even outside the protected areas and can be flagships for conservation in these areas, but their conservation aspects in these areas are poorly studied. We studied conservation aspects of a poorly known species, Yellow Monitor (Varanus flavescens), which is protected in most of its range countries, outside the protected areas in the Far-western lowlands of Nepal. We studied people's relationship, attitudes and threats to the species through questionnaire survey with adults and children in Parasan Village Development Committee of Kanchanpur District. We found that most of the adults were unaware about the protected status and importance of the species, and both adults as well as children killed the species. The study revealed that most of the killing occurred in agricultural land and children were more responsible for the killing than the adults. We found that monsoon vacation in schools increased the threat to the species. Our study revealed that fear from the species was the main reason and use of the species as food, medicine and hide were other reasons for killing of the species by adults. Low awareness was the major reason behind the killing by children as most of the killing was not related to any good reasons. We estimated that 87 individuals of the species could have been killed in the area in that year. Based on available evidences, we recommend further studies to predict the vulnerability of the species. Our study suggests that raising awareness among locals about its legal status and importance is the simple and efficient measure for the conservation of the species as well as for conserving other protected species outside the protected areas. 相似文献