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941.
Powerful states and elites frequently manage protected areas with little or no concern for historic land uses, people, or governance practices, justified by ideologies that portray these areas as “pure nature” to be protected from humans. New international participatory platforms, such as the UNESCO Man and Biosphere Program, coupled with strategic active agency, have provided an opportunity for challenging the fortress model of conservation in Israel. We examine the change in Israel’s government ecological policies following its failure in managing the Carmel forests, whereby its bargaining power with the local Druze-Arab minority was significantly reduced, opening a window of opportunity for the Druze to take advantage of new UNESCO rules on local participation to create management institutions for the local forest commons. 相似文献
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Pengxue Li Qiaozhi Yu Xu Gu Chunmiao Xu Shilian Qi Hong Wang Fenglin Zhong Tobias I. Baskin Abidur Rahman Shuang Wu 《Current biology : CB》2018,28(17):2777-2786.e2
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Hugh A. L. Henry Mehdi Abedi Concepción L. Alados Karen H. Beard Lauchlan H. Fraser Anke Jentsch Juergen Kreyling Andrew Kulmatiski Eric G. Lamb Wei Sun Mathew R. Vankoughnett Susanna Venn Christiane Werner Ilka Beil Irmgard Blindow Sven Dahlke Maren Dubbert Alexandra Effinger Heath W. Garris Maite Gartzia Tobias Gebauer Mohammed A. S. Arfin Khan Andrey V. Malyshev John Morgan Charles Nock Janelle P. Paulson Yolanda Pueyo Holly J. Stover Xuechen Yang 《Ecosystems》2018,21(7):1432-1444
Reduced precipitation treatments often are used in field experiments to explore the effects of drought on plant productivity and species composition. However, in seasonally snow-covered regions reduced precipitation also reduces snow cover, which can increase soil frost depth, decrease minimum soil temperatures and increase soil freeze–thaw cycles. Therefore, in addition to the effects of reduced precipitation on plants via drought, freezing damage to overwintering plant tissues at or below the soil surface could further affect plant productivity and relative species abundances during the growing season. We examined the effects of both reduced rainfall (via rain-out shelters) and reduced snow cover (via snow removal) at 13 sites globally (primarily grasslands) within the framework of the International Drought Experiment, a coordinated distributed experiment. Plant cover was estimated at the species level, and aboveground biomass was quantified at the functional group level. Among sites, we observed a negative correlation between the snow removal effect on minimum soil temperature and plant biomass production the next growing season. Three sites exhibited significant rain-out shelter effects on plant productivity, but there was no correlation among sites between the rain-out shelter effect on minimum soil moisture and plant biomass. There was no interaction between snow removal and rain-out shelters for plant biomass, although these two factors only exhibited significant effects simultaneously for a single site. Overall, our results reveal that reduced snowfall, when it decreases minimum soil temperatures, can be an important component of the total effect of reduced precipitation on plant productivity. 相似文献
945.
Immunological and functional characterization of Mycobacterium leprae protein antigens: an overview 总被引:2,自引:0,他引:2
Jelle E.R. Thole Brigitte Wieles Josephine E. Clark-Curtiss Tom H.M. Ottenhoff Tobias F. Rinke de Wit 《Molecular microbiology》1995,18(5):791-800
A major focus of leprosy research in the last 10 years has been the identification and characterization of antigens of Mycobacterium leprae that interact with antibodies and T cells of the host's immune response. Through the combined efforts of many different laboratories, a substantial number of protein antigens have been identified and characterized. In this MicroReview we present an updated list of M. leprae protein antigens, and, with emphasis on recent developments, summarize what is known regarding their functional and immunological features. 相似文献
946.
The effect of the crystal lattice on the side-chain conformation andside-chain dynamics in peptides is investigated by solid-state NMR, using thecyclic decapeptide antamanide as an example. The study takes advantage of the13C assignment of the backbone and side chains based on theresolution-enhanced 2D spin-diffusion spectra by heteronuclear and homonucleardecoupling. The spectra even allow for a stereospecific assignment of the-carbons of the valine residue. It is found that the valine side chaincoexists in two static rotamer conformations which have not been observed byX-ray crystallography. In addition, remarkable effects of the crystal packingon the methyl-group rotation frequency are found from 13Crelaxation measurements. 相似文献
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Tobias Riede Chad M. Eliason Edward H. Miller Franz Goller Julia A. Clarke 《Evolution; international journal of organic evolution》2016,70(8):1734-1746
Most birds vocalize with an open beak, but vocalization with a closed beak into an inflating cavity occurs in territorial or courtship displays in disparate species throughout birds. Closed‐mouth vocalizations generate resonance conditions that favor low‐frequency sounds. By contrast, open‐mouth vocalizations cover a wider frequency range. Here we describe closed‐mouth vocalizations of birds from functional and morphological perspectives and assess the distribution of closed‐mouth vocalizations in birds and related outgroups. Ancestral‐state optimizations of body size and vocal behavior indicate that closed‐mouth vocalizations are unlikely to be ancestral in birds and have evolved independently at least 16 times within Aves, predominantly in large‐bodied lineages. Closed‐mouth vocalizations are rare in the small‐bodied passerines. In light of these results and body size trends in nonavian dinosaurs, we suggest that the capacity for closed‐mouth vocalization was present in at least some extinct nonavian dinosaurs. As in birds, this behavior may have been limited to sexually selected vocal displays, and hence would have co‐occurred with open‐mouthed vocalizations. 相似文献