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81.
Powdery mildew is a common and widespread plant disease of considerable agronomic relevance. It is caused by obligate biotrophic fungal pathogens which, in most cases, epiphytically colonize aboveground plant tissues. The disease has been typically studied as a binary interaction of the fungal pathogen with its plant hosts, neglecting, for the most part, the mutual interplay with the wealth of other microorganisms residing in the phyllo- and/or rhizosphere and roots. However, the establishment of powdery mildew disease can be impacted by the presence/absence of host-associated microbiota (epi- and endophytes) and, conversely, plant colonization by powdery mildew fungi might disturb indigenous microbial community structures. In addition, other (foliar) phytopathogens could interact with powdery mildews, and mycoparasites may affect the outcome of plant–powdery mildew interactions. In this review, we discuss the current knowledge regarding the intricate and multifaceted interplay of powdery mildew fungi, host plants and other microorganisms, and outline current gaps in our knowledge, thereby setting the basis for potential future research directions. 相似文献
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Emanuele Bocchieri 《Plant biosystems》2013,147(5-6):325-336
Abstract The results of two years of collection in a small isle in the southern Sardinia are reported, consisting in a floristic list of 116 entities distributed in 96 genera and 41 families. The biological spectrum of this flora puts in evidence a typical Mediterranean environment, characterized by a marked summer dryness. The ratio: number of entities/surface of the studied site has been compared with that of other small southern Sardinian islands, resulting the highest value. This floristic aspect, as well as differences in the biological spectrum, is interpreted as the result of the presence in the area under study of a desultory link with the mainland, in form of a sandy isthmus. This seems important in breaking the biological balance of the small island. 相似文献
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Reavis Zackery W. Mirjankar Nikhil Sarangi Srikant Boyle Stephen H. Kuhn Cynthia M. Matson Wayne R. Babyak Michael A. Matson Samantha A. Siegler Ilene C. Kaddurah‑Daouk Rima Suarez Edward C. Williams Redford B. Grichnik Katherine Stafford‑Smith Mark Georgiades Anastasia 《Metabolomics : Official journal of the Metabolomic Society》2021,17(6):1-13
Metabolomics - Metabolomics applications to the aquaculture research are increasing steadily. The use of standardized proton nuclear magnetic resonance (1H NMR) spectroscopy can provide the... 相似文献
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Valentina Sanghez Maria Teresa Russo Maria Antonietta Ajmone‐Cat Emanuele Cacci Alberto Martire Patrizia Popoli Germana Falcone Flavia Michelini Marco Crescenzi Paolo Degan Luisa Minghetti Margherita Bignami Gemma Calamandrei 《Aging cell》2013,12(4):695-705
The contribution that oxidative damage to DNA and/or RNA makes to the aging process remains undefined. In this study, we used the hMTH1‐Tg mouse model to investigate how oxidative damage to nucleic acids affects aging. hMTH1‐Tg mice express high levels of the hMTH1 hydrolase that degrades 8‐oxodGTP and 8‐oxoGTP and excludes 8‐oxoguanine from both DNA and RNA. Compared to wild‐type animals, hMTH1‐overexpressing mice have significantly lower steady‐state levels of 8‐oxoguanine in both nuclear and mitochondrial DNA of several organs, including the brain. hMTH1 overexpression prevents the age‐dependent accumulation of DNA 8‐oxoguanine that occurs in wild‐type mice. These lower levels of oxidized guanines are associated with increased longevity and hMTH1‐Tg animals live significantly longer than their wild‐type littermates. Neither lipid oxidation nor overall antioxidant status is significantly affected by hMTH1 overexpression. At the cellular level, neurospheres derived from adult hMTH1‐Tg neural progenitor cells display increased proliferative capacity and primary fibroblasts from hMTH1‐Tg embryos do not undergo overt senescence in vitro. The significantly lower levels of oxidized DNA/RNA in transgenic animals are associated with behavioral changes. These mice show reduced anxiety and enhanced investigation of environmental and social cues. Longevity conferred by overexpression of a single nucleotide hydrolase in hMTH1‐Tg animals is an example of lifespan extension associated with healthy aging. It provides a link between aging and oxidative damage to nucleic acids. 相似文献
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Sylvaine You Luca Piali Chantal Kuhn Beat Steiner Virginia Sauvaget Fabrice Valette Martine Clozel Jean-Fran?ois Bach Lucienne Chatenoud 《PloS one》2013,8(10)
In the present study, we investigated the therapeutic potential of a selective S1P1 receptor modulator, ponesimod, to protect and reverse autoimmune diabetes in non-obese diabetic (NOD) mice. Ponesimod was administered orally to NOD mice starting at 6, 10, 13 and 16 weeks of age up to 35 weeks of age or to NOD mice showing recent onset diabetes. Peripheral blood and spleen B and T cell counts were significantly reduced after ponesimod administration. In pancreatic lymph nodes, B lymphocytes were increased and expressed a transitional 1-like phenotype. Chronic oral ponesimod treatment efficiently prevented autoimmune diabetes in 6, 10 and 16 week-old pre-diabetic NOD mice. Treatment withdrawal led to synchronized disease relapse. Ponesimod did not inhibit the differentiation of autoreactive T cells as assessed by adoptive transfer of lymphocytes from treated disease-free NOD mice. In addition, it did not affect the migration, proliferation and activation of transgenic BDC2.5 cells into the target tissue. However, ponesimod inhibited spreading of the T cell responses to islet-specific glucose-6-phosphatase catalytic subunit-related protein (IGRP). Treatment of diabetic NOD mice with ponesimod induced disease remission. However, here again, upon treatment cessation, the disease rapidly recurred. This recurrence was effectively prevented by combination treatment with a CD3 antibody leading to the restoration of self-tolerance. In conclusion, treatment with a selective S1P1 modulator in combination with CD3 antibody represents a promising therapeutic approach for the treatment of autoimmune diabetes. 相似文献