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991.
992.
Incubation of blowfly salivary gland homogenates with 30 microM [gamma-32P]ATP resulted in a rapid, Mg2+-dependent, synthesis of [32P]polyphosphoinositides and [32P]phosphatidic acid. 5-Methyltryptamine, in the presence of 10 microM guanosine 5'-(3-O-thio)trisphosphate, reduced the net accumulation of 32P label into phosphatidylinositol-4,5-P2 and phosphatidylinositol-4-P by 35 and 20%, respectively. 5-Methyltryptamine did not affect synthesis of [32P]phosphatidic acid. Phosphorylation of polyphosphoinositides was not affected by 5-methyltryptamine. In membranes labeled in vitro with [gamma-32P]ATP, 5-methyltryptamine stimulated a rapid breakdown of the [32P]polyphosphoinositides. These results indicate that in blowfly salivary gland homogenates, hormone stimulates breakdown of the newly synthesized polyphosphoinositides. In the presence of hormone, the rate of polyphosphoinositide synthesis does not compensate for the rate of polyphosphoinositide degradation. 相似文献
993.
994.
Herpesvirus neutralization: the role of complement 总被引:5,自引:0,他引:5
995.
Intraperitoneal injection of phencyclidine before intravenous injection of [3H] Quinuclidinyl benzilate (QNE, 1.6 μg/kg) significantly increased the amount of radioactivity found in the brains of female C57BL/6J mice one hour after the 3H-QNB administration. This effect was found in hypothalamus, cortex, hippocampus and striatum and was decreased by pretreatment of the animal with atropine. The magnitude of the enhancement varied as a function of dose but did not change across the time span studied. These data are in contrast to our findings and those of others of inhibition of the specific binding of 3H-QNB to muscarinic cholinergic receptors by PCP . When atropine or PCP was administered and the tissue later analyzed , no effects of the drugs were observed on 3H-QNB binding. The reasons for the differences remain a matter of speculation. 相似文献
996.
Edouard E. Galyov Michael W. Wood Roland Rosqvist Paul B. Mullan Patricia R. Watson Samantha Hedges & Tim S. Wallis 《Molecular microbiology》1997,25(5):903-912
Enteritis induced by non-typhoid pathogenic Salmonella is characterized by fluid secretion and inflammatory responses in the infected ileum. The inflammatory response provoked by Salmonella initially consists largely of a neutrophil (PMN) migration into the intestinal mucosa and the gut lumen. The interactions between Salmonella and intestinal epithelial cells are known to play an essential role in inducing the inflammatory response. Upon interaction with epithelial cells salmonellae are able to elicit transepithelial signalling to neutrophils. This signalling is recognized as a key virulence feature underlying Salmonella -induced enteritis. However, the nature and mechanism of such signalling has not been clarified to date. Here, we characterize SopB, a novel secreted effector protein of Salmonella dublin , and present data implying that SopB is translocated into eukaryotic cells via a sip -dependent pathway to promote fluid secretion and inflammatory responses in the infected ileum. 相似文献
997.
Gillian Borland Rebecca J. Bird Timothy M. Palmer Stephen J. Yarwood 《The Journal of biological chemistry》2009,284(26):17391-17403
998.
The facilities available to disabled people living in Scotland were studied by visiting and interviewing a group of 50 paraplegics living in Glasgow and the surrounding counties. The degree of unemployment in the group (74%) was far greater than has been reported in other surveys, and no quadriplegic was in remunerative employment. Though the general unemployment level in the area is high services to help the disabled gain employment were only partially utilized.Liaison between social workers was not always successful. Some paraplegics were visited at home by both a medical social worker and a local authority social worker, while others were not supported by either. There was no apparent attempt by local authorities to identify the disabled, as is required in England under Section 1 of the Chronically Sick and Disabled Persons Act, 1970. Several paraplegics lacked facilities which are covered by Section 2 of the Act. The exclusion of Scotland from Sections 1 and 2 of the Chronically Sick and Disabled Persons Act may widen the differences between the two countries as the Scottish legislation is less specific. 相似文献
999.
1000.
Jane L. DeGabriel Ben D. Moore Annika M. Felton Jörg U. Ganzhorn Caroline Stolter Ian R. Wallis Christopher N. Johnson William J. Foley 《Oikos》2014,123(3):298-308
A central goal of nutritional ecology is to understand how variation in food quality limits the persistence of wild animal populations. Habitat suitability for browsing mammals is strongly affected by concentrations of nutrients and plant secondary metabolites (PSMs), but our understanding of this is based mostly on short‐term experiments of diet selection involving captive animals. In the wild, browsers forage in biologically, chemically and spatially‐complex environments, and foraging decisions in response to varying food quality will be correspondingly complicated. We have identified four steps that must be achieved in order to translate our understanding from laboratory experiments to populations of mammalian browsers: 1) knowing what foods and how much of these wild browsers eat, as well as what they avoid eating; 2) knowing the relevant aspects of plant nutritional and defensive chemistry to measure in a given system and how to measure them; 3) understanding the spatial distribution of nutrients and PSMs in plant communities, the costs they impose on foraging and the effects on animals’ distributions; and 4) having appropriate statistical tools to analyse the data. We discuss prospects for each of these prerequisites for extending laboratory studies of nutritional quality, and review recent developments that may offer solutions for field studies. We also provide a synthesis of how to use this nutritional knowledge to link food quality to population regulation in wild mammals and describe examples that have successfully achieved this aim. 相似文献