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971.
972.
T Weiss L Beyer E Hansen R Rost A Wolf 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》1990,40(5):925-929
EEG changes were studied in the case of real movements (wrestlers training) and also in the case of imagination of motor activity (ideomotor training). Statistically significant increases were found of the average frequency of oscillations in the EEG alpha-range and simultaneously typical vegetative changes. Thus, imagination of motor activity may serve as a model for studying the CNS activation processes in connection with the realization of real motor activity. 相似文献
973.
Diego F. Correa Hawthorne L. Beyer Hugh P. Possingham Skye R. Thomas‐Hall Peer M. Schenk 《Global Change Biology Bioenergy》2019,11(8):914-929
Sustainable alternatives to fossil fuels are urgently needed to avoid severe climate impacts and further environmental degradation. Microalgae are one of the most productive crops globally and do not need to compete for arable land or freshwater resources. Hence, they may become a promising, more sustainable cultivation alternative for the large‐scale production of biofuels provided that substantial reductions are achieved in their production costs. In this study, we identify the most suitable areas globally for siting microalgal farms for biodiesel production that maximize profitability and minimize direct competition with food production and direct impacts on biodiversity, based on a spatially explicit multiple‐criteria decision analysis. We further explore the relationships between microalgal production, agricultural value, and biodiversity, and propose several solutions for siting microalgal production farms, based on current and future targets in energy production using integer linear programming. If using seawater for microalgal cultivation, biodiesel production could reach 5.85 × 1011 L/year based on top suitable lands (i.e., between 13% and 16% of total transport energy demands in 2030) without directly competing with food production and areas of high biodiversity value. These areas are particularly abundant in the dry coasts of North and East Africa, the Middle East, and western South America. This is the first global analysis that incorporates economic and environmental feasibility for microalgal production sites. Our results can guide the selection of best locations for biofuel production using microalgae while minimizing conflicts with food production and biodiversity conservation. 相似文献
974.
975.
976.
Vaginal-cervical mechanostimulation (VS) suppresses vocalization and withdrawal responses to noxious stimulation. To determine whether the inhibitory neurotransmitter, glycine, contributes to the action of VS, strychnine, a specific glycine receptor antagonist was administered perispinally via intrathecal catheter in dosages of 1,5,25 and 100 micrograms. Prior to strychnine administration, VS (400 g force) elevated thresholds to elicit vocalization in response to graded intensities of tail shock, and blocked vocalization elicited by stimulation of a skin area, previously sensitized by intradermal injection of a 20% yeast solution. After strychnine administration the analgesic effects of VS were significantly attenuated. These findings suggest that the analgesic action of VS is partially mediated by glycine at the spinal level. 相似文献
977.
978.
Jakob Beyer Samir Jabari Tilman T. Rau Winfried Neuhuber Axel Brehmer 《Histochemistry and cell biology》2013,140(2):157-167
The submucous layers of human small and large intestines contain at least two separate neuron populations. Besides morphological features, they differ in their immunoreactivities for calretinin (CALR) and somatostatin (SOM), respectively. In this study, submucosal wholemounts of 23 patients or body donors (including all segments of small intestine and colon) were immunohistochemically quadruple stained for CALR and SOM as well as for substance P (SP) and choline acetyltransferase (ChAT). We found that all SOM-positive neurons co-stained for ChAT and the majority for SP [between 50 % in the small intestinal external submucosal plexus (ESP) and 75 % in the colonic ESP]. In contrast, a majority of CALR-neurons contained ChAT (between 77 % in the small intestinal ESP and 92 % in the large intestinal ESP) whereas less than 4 % of CALR-neurons were co-immunoreactive for SP. Another set of wholemounts was co-stained for peripherin, a marker enabling morphological analysis. Where identifiable, both SOM alone- and SOM/SP-neurons displayed a uniaxonal (supposed pseudouniaxonal) morphology. We suggest that the chemical code of SOM-immunoreactive, human submucosal neurons may be “ChAT+/SOM+/SP±”. In additional sections double stained for SOM and SP, we regularly found double-labelled nerve fibres only in the mucosa. In contrast, around submucosal arteries mostly SOM alone- fibres were found and the muscularis propria contained numerous SP-alone fibres. We conclude that the main target of submucosal SOM(/SP)-neurons may be the mucosa. Due to their morpho-chemical similarity to human myenteric type II neurons, we further suggest that one function of human submucosal SOM-neurons may be a primary afferent one. 相似文献
979.
980.
Soils of the Admiralty Bay region at King George Island, maritime Antarctic are described and analysed for invertebrates
and microorganisms. Results showed a great variety of soils: cambisols, umbrisols, regosols, podzols, leptosols, gleysols
and relic ornithogenic soils were found. Surface layers, especially of cambisols, umbrisols and podzols, showed a diverse
fauna, governed by nematodes, collemboles and mites. The bacterial flora is analysed for total counts and biomass distribution
in different layers using epifluorescence microscopy. Influences of soil organic matter can be described by different patterns
of mean bacterial cell volumes related to soil cover and depth distributions.
Received: 21 February 1997 / Accepted: 28 April 1997 相似文献