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121.
Shender Lisa A. Cody Theresa Ruder Mark Fenton Heather Niedringhaus Kevin D. Blanton Jason Motes Jessy Schmedes Sarah Forys Elizabeth 《EcoHealth》2022,19(2):203-215
EcoHealth - Extreme weather events, particularly heavy rainfall, are occurring at greater frequency with climate change. Although adverse human health effects from heavy rainfall are often... 相似文献
122.
123.
Jackson Oyindamola Quilliam Richard S. Stott Andy Grant Helen Subke Jens-Arne 《Plant and Soil》2019,437(1-2):473-485
Plant and Soil - Root exudation is an important carbon (C) and energy source for soil microorganisms but quantifying its spatial distribution is challenging. We tested whether 14C imaging (analogue... 相似文献
124.
Eun Hye Park Stephen Keeley Cristina Savin James B. Ranck André A. Fenton 《Neuron》2019,101(2):285-293.e5
125.
dm Lovas‐Kiss Marta I. Snchez David M. Wilkinson Neil E. Coughlan Jos A. Alves Andy J. Green 《Ecography》2019,42(5):956-967
Shorebirds (Charadriiformes) undergo rapid migrations with potential for long‐distance dispersal (LDD) of plants. We studied the frequency of endozoochory by shorebirds in different parts of Europe covering a broad latitudinal range and different seasons. We assessed whether plants dispersed conformed to morphological dispersal syndromes. A total of 409 excreta samples (271 faeces and 138 pellets) were collected from redshank Tringa totanus, black‐winged stilt Himantopus himantopus, pied avocet Recurvirostra avosetta, northern lapwing Vanellus vanellus, Eurasian curlew Numenius arquata and black‐tailed godwit Limosa limosa in south‐west Spain, north‐west England, southern Ireland and Iceland in 2005 and 2016, and intact seeds were extracted and identified. Godwits were sampled just before or after migratory movements between England and Iceland. The germinability of seeds was tested. Intact diaspores were recovered from all bird species and study areas, and were present in 13% of samples overall. Thirteen plant families were represented, including Charophyceae and 26 angiosperm taxa. Only four species had an ‘endozoochory syndrome’. Four alien species were recorded. Ellenberg values classified three species as aquatic and 20 as terrestrial. Overall, 89% of seeds were from terrestrial plants, and 11% from aquatic plants. Average seed length was higher in redshank pellets than in their faeces. Six species were germinated, none of which had an endozoochory syndrome. Seeds were recorded during spring and autumn migration. Plant species recorded have broad latitudinal ranges consistent with LDD via shorebirds. Crucially, morphological syndromes do not adequately predict LDD potential, and more empirical work is required to identify which plants are dispersed by shorebirds. Incorporating endozoochory by shorebirds and other migratory waterbirds into plant distribution models would allow us to better understand the natural processes that facilitated colonization of oceanic islands, or to improve predictions of how plants will respond to climate change, or how alien species spread. 相似文献
126.
Ian P. Holmes Richard J. Blunt Olivier E. Lorthioir Stephen M. Blowers Andy Gribble Andrew H. Payne Ian G. Stansfield Martyn Wood Patrick M. Woollard Charlie Reavill Claire M. Howes Fabrizio Micheli Romano Di Fabio Daniele Donati Silvia Terreni Dieter Hamprecht Luca Arista Angela Worby Steve P. Watson 《Bioorganic & medicinal chemistry letters》2010,20(6):2013-2016
The identification of a highly selective D2 partial agonist, D3 antagonist tool molecule which demonstrates high levels of brain exposure and selectivity against an extensive range of dopamine, serotonin, adrenergic, histamine, and muscarinic receptors is described. 相似文献
127.
Nicola Bryson-Morrison Andy Beer Aly Gaspard Soumah Tetsuro Matsuzawa Tatyana Humle 《American journal of primatology》2020,82(3):e23102
Agricultural expansion encroaches on tropical forests and primates in such landscapes frequently incorporate crops into their diet. Understanding the nutritional drivers behind crop-foraging can help inform conservation efforts to improve human-primate coexistence. This study builds on existing knowledge of primate diets in anthropogenic landscapes by estimating the macronutrient content of 24 wild and 11 cultivated foods (90.5% of food intake) consumed by chimpanzees (Pan troglodytes verus) at Bossou, Guinea, West Africa. We also compared the macronutrient composition of Bossou crops to published macronutrient measures of crops from Bulindi, Uganda, East Africa. The composition of wild fruits, leaves, and pith were consistent with previous reports for primate diets. Cultivated fruits were higher in carbohydrates and lower in insoluble fiber than wild fruits, while wild fruits were higher in protein. Macronutrient content of cultivated pith fell within the ranges of consumed wild pith. Oil palm food parts were relatively rich in carbohydrates, protein, lipids, and/or fermentable fiber, adding support for the nutritional importance of the oil palm for West African chimpanzees. We found no differences in the composition of cultivated fruits between Bossou and Bulindi, suggesting that macronutrient content alone does not explain differences in crop selection. Our results build on the current understanding of chimpanzee feeding ecology within forest-agricultural mosaics and provide additional support for the assumption that crops offer primates energetic benefits over wild foods. 相似文献
128.
Staron RS Kraemer WJ Hikida RS Fry AC Murray JD Campos GE 《Histochemistry and cell biology》1999,111(2):117-123
The limb and trunk muscles of adult rats express four myosin heavy chain (MHC) isoforms, one slow (MHCI) and three fast (MHCIIa,
MHCIId, and MHCIIb). The distribution of these isoforms correlates with fiber types delineated using myofibrillar actomyosin
adenosine triphosphatase (mATPase) histochemistry. For example, type I fibers express MHCI and fiber types IIA, IID, and IIB
express MHCIIa, MHCIId, and MHCIIb, respectively. Fibers containing only one MHC isoform have been termed ”pure” fibers. Recent
evidence suggests that a population of ”hybrid” fibers exist in rat skeletal muscle which contain two MHC isoforms. The purpose
of the present investigation was to document the entire range of histochemically defined ”pure” and ”hybrid” fiber types in
untreated muscles of the young adult Fisher 344 rat hindlimb. The selected hindlimb muscles (soleus, tibialis anterior, extensor
digitorum longus, and gastrocnemius muscles) were removed from 12 male rats and analyzed for muscle fiber type distribution,
cross-sectional area, and MHC content. Care was taken to delineate eight fiber types (I, IC, IIC, IIA, IIAD, IID, IIDB, and
IIB) using refined histochemical techniques. Hybrid fibers were found to make up a considerable portion of the muscles examined
(a range of 8.8–17.8% of the total). The deep red portion of the gastrocnemius muscle contained the largest number of hybrid
fibers, most of which were the fast types IIAD (8.5±2.8%) and IIDB (5.2±2.3%). In conclusion, hybrid fibers make up a considerable
portion of normal rat limb musculature and are an important population that should not be ignored.
Accepted: 15 October 1998 相似文献
129.
130.
Bcl-2 family proteins regulate mitochondrial reactive oxygen production and protect against oxidative stress 总被引:6,自引:0,他引:6
Bcl-2 family proteins protect against a variety of forms of cell death, including acute oxidative stress. Previous studies have shown that overexpression of the antiapoptotic protein Bcl-2 increases cellular redox capacity. Here we report that cell lines transfected with Bcl-2 paradoxically exhibit increased rates of mitochondrial H(2)O(2) generation. Using isolated mitochondria, we determined that increased H(2)O(2) release results from the oxidation of reduced nicotinamide adenine dinucleotide-linked substrates. Antiapoptotic Bcl-2 family proteins Bcl-xL and Mcl-1 also increase mitochondrial H(2)O(2) release when overexpressed. Chronic exposure of cells to low levels of the mitochondrial uncoupler carbonyl cyanide 4-(triflouromethoxy)phenylhydrazone reduced the rate of H(2)O(2) production by Bcl-xL overexpressing cells, resulting in a decreased ability to remove exogenous H(2)O(2) and enhanced cell death under conditions of acute oxidative stress. Our results indicate that chronic and mild elevations in H(2)O(2) release from Bcl-2, Bcl-xL, and Mcl-1 overexpressing mitochondria lead to enhanced cellular antioxidant defense and protection against death caused by acute oxidative stress. 相似文献