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QTL for resistance to Salmonella carrier state confirmed in both experimental and commercial chicken lines 总被引:1,自引:0,他引:1
F. Calenge F. Lecerf J. Demars K. Feve F. Vignoles F. Pitel A. Vignal P. Velge N. Sellier C. Beaumont 《Animal genetics》2009,40(5):590-597
The ability of chickens to carry Salmonella without displaying disease symptoms is responsible for Salmonella propagation in poultry stocks and for subsequent human contamination through the consumption of contaminated eggs or meat. The selection of animals more resistant to carrier state might be a way to decrease the propagation of Salmonella in poultry stocks and its transmission to humans. Five QTL controlling variation for resistance to carrier state in a chicken F2 progeny derived from the White Leghorn inbred lines N and 61 had been previously identified using a selective genotyping approach. Here, a second analysis on the whole progeny was performed, which led to the confirmation of two QTL on chromosomes 2 and 16. To assess the utility of these genomic regions for selection in commercial lines, we tested them together with other QTL identified in an [N×61 ] × N backcross progeny and with the candidate genes SLC11A1 and TLR4 . We used a commercial line divergently selected for either low or high carrier-state resistance both in young chicks and in adult hens. In divergent chick lines, one QTL on chromosome 1 and one in the SLC11A1 region were significantly associated with carrier-state resistance variations; in divergent adult lines, one QTL located in the major histocompatibility complex on chromosome 16 and one in the SLC11A1 region were involved in these variations. Genetic studies conducted on experimental lines can therefore be of potential interest for marker-assisted selection in commercial lines. 相似文献
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95.
There is a need for safe medications that can effectively support recovery by treating symptoms of protracted abstinence that may precipitate relapse in alcoholics, e.g. craving and disturbances in sleep and mood. This proof-of-concept study reports on the effectiveness of gabapentin 1200 mg for attenuating these symptoms in a non-treatment-seeking sample of cue-reactive, alcohol-dependent individuals. Subjects were 33 paid volunteers with current Diagnostic and Statistical Manual of Mental Disorders-IV alcohol dependence and a strength of craving rating 1 SD or greater for alcohol than water cues. Subjects were randomly assigned to gabapentin or placebo for 1 week and then participated in a within-subjects trial where each was exposed to standardized sets of pleasant, neutral and unpleasant visual stimuli followed by alcohol or water cues. Gabapentin was associated with significantly greater reductions than placebo on several measures of subjective craving for alcohol as well as for affectively evoked craving. Gabapentin was also associated with significant improvement on several measures of sleep quality. Side effects were minimal, and gabapentin effects were not found to resemble any major classes of abused drugs. Results suggest that gabapentin may be effective for treating the protracted abstinence phase in alcohol dependence and that a randomized clinical trial would be an appropriate next step. The study also suggests the value of cue-reactivity studies as proof-of-concept screens for potential antirelapse drugs. 相似文献
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Individual specialisation can lead to the exploitation of different trophic and habitat resources and the production of morphological
variability within a population. Although the ecological causes of this phenomenon are relatively well known, its consequences
on individual fitness are less recognised. We have investigated the extent of individual specialisation in resource use and
trophic morphology and its fitness consequences through a combination of tagging–recapture, stable isotope analyses and telemetry.
The European eel (Anguilla anguilla) was the model species as it displays significant variability in head shape. Independent to their body length, individuals
with broader heads displayed a significantly higher trophic position (δ15N) than individuals with narrower heads. This corresponded with a significantly higher proportion of prey fish in their diet
compared with invertebrates and was associated with the use of a habitat niche located further from the river bank. The European
eel therefore provides a rare empirical example of individual specialisation in resource use and trophic morphology in a natural
population occurring at a very small spatial scale. Individuals with intermediate head morphology displayed lower body condition
(a proxy of fitness) than individuals with extreme head morphology (i.e. narrower and broader headed individuals), demonstrating
the existence of disruptive selection associated with individual specialisation. 相似文献
98.
Sadeyen JR Trotereau J Velge P Marly J Beaumont C Barrow PA Bumstead N Lalmanach AC 《Microbes and infection / Institut Pasteur》2004,6(14):1278-1286
Asymptomatic Salmonella enterica serovar Enteritidis carrier state in poultry has serious consequences on food safety and public health due to the risks of food poisoning following consumption of contaminated products. An understanding the mechanisms of persistence of Salmonella in the digestive tract of chicken can be achieved by a better knowledge of the defects in the control of infection in susceptible versus resistant animals. The gene expression of innate immune response factors including anti-microbial molecules, inflammatory and anti-infectious cytokines was studied in the caecal lymphoid tissue associated with the carrier state. Expression levels of these genes were assessed by real-time PCR and were compared in two inbred lines of chickens differing in resistance to the carrier state following oral inoculation of S. enterica serovar Enteritidis at 1 week of age. No correlation was observed between resistance/susceptibility to caecal carrier state and level of interleukin (IL)-1beta, IL-8, IL-18, inducible NO synthase (iNOS) and natural resistance associated macrophage protein 1 (NRAMP1). A high baseline level of defensin gene expression was recorded in young animals from the susceptible line. In contrast, a significantly low expression of interferon-gamma (IFN-gamma) gene was observed in these susceptible infected animals in comparison to resistant ones and healthy counterparts. IFN-gamma expression level represents a valuable indication of immunodeficiency associated with persistence of Salmonella in the chicken digestive tract, and IFN-gamma thus represents a factor to consider in the development of prophylactic measures for the reduction of Salmonella carrier state. 相似文献
99.
Laure Frésard Sophie Leroux Bertrand Servin David Gourichon Patrice Dehais Magali San Cristobal Nathalie Marsaud Florence Vignoles Bertrand Bed'hom Jean-Luc Coville Farhad Hormozdiari Catherine Beaumont Tatiana Zerjal Alain Vignal Mireille Morisson Sandrine Lagarrigue Frédérique Pitel 《Nucleic acids research》2014,42(6):3768-3782
100.
Thanh-Son Tran Agnès Narcy Bernard Carré Irène Gabriel Nicole Rideau Hélène Gilbert Olivier Demeure Bertrand Bed’Hom Céline Chantry-Darmon Marie-Yvonne Boscher Denis Bastianelli Nadine Sellier Marie Chabault Fanny Calenge Elisabeth Le Bihan-Duval Catherine Beaumont Sandrine Mignon-Grasteau 《遗传、选种与进化》2014,46(1):25