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101.
Influences of extreme weather,climate and pesticide use on invertebrates in cereal fields over 42 years
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Julie A. Ewald Christopher J. Wheatley Nicholas J. Aebischer Stephen J. Moreby Simon J. Duffield Humphrey Q. P. Crick Michael B. Morecroft 《Global Change Biology》2015,21(11):3931-3950
Cereal fields are central to balancing food production and environmental health in the face of climate change. Within them, invertebrates provide key ecosystem services. Using 42 years of monitoring data collected in southern England, we investigated the sensitivity and resilience of invertebrates in cereal fields to extreme weather events and examined the effect of long‐term changes in temperature, rainfall and pesticide use on invertebrate abundance. Of the 26 invertebrate groups examined, eleven proved sensitive to extreme weather events. Average abundance increased in hot/dry years and decreased in cold/wet years for Araneae, Cicadellidae, adult Heteroptera, Thysanoptera, Braconidae, Enicmus and Lathridiidae. The average abundance of Delphacidae, Cryptophagidae and Mycetophilidae increased in both hot/dry and cold/wet years relative to other years. The abundance of all 10 groups usually returned to their long‐term trend within a year after the extreme event. For five of them, sensitivity to cold/wet events was lowest (translating into higher abundances) at locations with a westerly aspect. Some long‐term trends in invertebrate abundance correlated with temperature and rainfall, indicating that climate change may affect them. However, pesticide use was more important in explaining the trends, suggesting that reduced pesticide use would mitigate the effects of climate change. 相似文献
102.
Maan S Maan NS Pullinger G Nomikou K Morecroft E Guimera M Belaganahalli MN Mertens PP 《Journal of virology》2012,86(10):5971-5972
Bluetongue virus is the type species of the genus Orbivirus in the family Reoviridae. We report the first complete genome sequence of an isolate (IND2004/01) of bluetongue virus serotype 10 (BTV-10) from Andhra Pradesh, India. This isolate, which is stored in the Orbivirus Reference Collection (ORC) at IAH Pirbright, shows >99% nucleotide identity in all 10 genome segments with a vaccine strain of BTV-10 from the United States. 相似文献
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104.
The Stomach, Helicobacter pylori, and Acid Secretion 总被引:1,自引:0,他引:1
105.
Dorsey DA Mascó DH Dikranian K Hyrc K Masciotra L Faddis B Soriano M Gru AA Goldberg MP de Erausquin GA 《Apoptosis : an international journal on programmed cell death》2006,11(4):535-544
Developing neuronal populations undergo significant attrition by natural cell death. Dopaminergic neurons in the substantia
nigra pars compacta undergo apoptosis during synaptogenesis. Following this time window, destruction of the anatomic target
of dopaminergic neurons results in dopaminergic cell death but the morphology is no longer apoptotic. We describe ultrastructural
changes that appear unique to dying embryonic dopaminergic neurons. In primary cultures of mesencephalon, death of dopaminergic
neurons is triggered by activation of glutamate receptors sensitive to alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic
acid (AMPA), and differs ultrastructurally from both neuronal apoptosis or typical excitotoxicity. AMPA causes morphological
changes selectively in dopaminergic neurons, without affecting other neurons in the same culture dishes. Two hours after the
onset of treatment swelling of Golgi complexes is apparent. At 3 h, dopaminergic neurons display loss of membrane asymmetry
(coinciding with commitment to die), as well as nuclear membrane invagination, irregular aggregation of chromatin, and mitochondrial
swelling. Nuclear changes continue to worsen until loss of cytoplasmic structures and cell death begins to occur after 12 h.
These changes are different from those described in neurons undergoing either apoptosis or excitotoxic death, but are similar
to ultrastructural changes observed in spontaneous death of dopaminergic neurons in the natural mutant weaver mouse. 相似文献
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Substance abuse and dependence is the most common psychiatric problem. Alcohol is the most commonly abused substance and most people who abuse other substance(s) abuse alcohol at the same time. Accumulating evidence suggests that neurophysiological and pathological effects of ethanol are mediated to a considerable extent via the glutamatergic system. Ethanol disrupts glutamatergic neurotransmission by inhibiting the response of the N-methyl-D-aspartate (NMDA) receptor and by promoting neuronal toxicity through upregulation of the NMDA receptor density. Therefore, short-term/acute ethanol treatment results in a blockade of NMDA receptor-mediated neurotransmission and apoptotic cell death by inhibiting the trophic effect mediated by the NMDA receptor whereas chronic ethanol treatment and withdrawal results in an enhanced toxic response toward glutamate. The neurobiology of human alcoholism such as ethanol intoxication, dependence, withdrawal seizures, delirium tremens, Wernicke-Korsakoff syndrome, and fetal alcohol syndrome can be better understood as a spectrum of consequences of ethanol's effect on the NMDA glutamatergic system. 相似文献
109.
Toshifumi Noguchi MD PhD Naoto Yamada Miyuki Sadamatsu Nobumasa Kato 《Journal of biomedical science》1998,5(3):221-225
We assayed the diurnal concentrations of growth hormone (GH) and prolactin (PRL) in 6 healthy male volunteers to evaluate the self-similar features in the time series of each hormone on the basis of fractal theory and to determine the fractal dimension as an index of the complexity of the diurnal variation. In addition, we assessed the effects of a 6-hour delay in the sleep period on the complexity of the diurnal variaton of these hormones. There was a statistically significant fractal feature in the serum levels of GH both under the nocturnal-sleep and delayed-sleep conditions in all subjects. The time series of the serum PRL concentrations also showed a statistically significant fractal feature under the nocturnal-sleep and delayed-sleep conditions in all subjects. The fractal dimensions of the patterns of the GH or PRL levels were 1.879 and 1.929 or 1.754 and 1.785 under the nocturnal-sleep and delayed-sleep conditions, respectively. Two-way ANOVA revealed no significant difference in the fractal dimension between the two sleep conditions but did reveal a significant difference between the fractal dimensions of the GH and PRL levels. These results showed (1) that delayed sleep had no significant effect on the complexity of the diurnal pattern of these hormones, and (2) that the diurnal pattern of the GH levels was more complex than that of the PRL levels. 相似文献
110.