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51.
52.
Mark R. Ibberson John P. Copier Elena Llop Cristina Navarrete Adrian V. S. Hill J. Kennedy Cruickshank A. K. L. So 《Immunogenetics》1997,47(2):124-130
Interactions involving the T-cell receptor (TCR) and major histocompatibility complex (MHC) are fundamental to the generation
of a specific immune response. The study of interpopulation differences in TCR genes may identify those genes which are subject to selection, and also provides useful information for future genetic studies
in these populations. In this study we present analysis of five TCRAV polymorphisms, for V5S1, V6S1, V8S1, V17S1, and V21S1 loci in five human populations by single-strand conformational polymorphism (SSCP) analysis. Caucasian, Chinese, Gambian,
AfroCaribbean, and South American Indians (Mapuches) showed marked interpopulation variation for both the silent (V5S1, V17S1, and V21S1) and coding (V6S1 and V8S1) polymorphisms. In general the alleles were conserved in the different populations, but new, additional variants were found
for V5S1 and V17S1 in Gambians and Caucasians. V6S1 overall showed the highest nucleotide diversity, and V6S1 genotype distributions were skewed away from expected values in Chinese and Mapuches. Analysis of allelic associations showed
a general lack of linkage disequilibrium between the loci, which was reflected by the absence of strong population-specific
haplotypes.
Received: 22 April 1997 / Revised: 9 July 1997 相似文献
53.
Ana F. Navarrete Simon M. Reader Sally E. Street Andrew Whalen Kevin N. Laland 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2016,371(1690)
In birds and primates, the frequency of behavioural innovation has been shown to covary with absolute and relative brain size, leading to the suggestion that large brains allow animals to innovate, and/or that selection for innovativeness, together with social learning, may have driven brain enlargement. We examined the relationship between primate brain size and both technical (i.e. tool using) and non-technical innovation, deploying a combination of phylogenetically informed regression and exploratory causal graph analyses. Regression analyses revealed that absolute and relative brain size correlated positively with technical innovation, and exhibited consistently weaker, but still positive, relationships with non-technical innovation. These findings mirror similar results in birds. Our exploratory causal graph analyses suggested that technical innovation shares strong direct relationships with brain size, body size, social learning rate and social group size, whereas non-technical innovation did not exhibit a direct relationship with brain size. Nonetheless, non-technical innovation was linked to brain size indirectly via diet and life-history variables. Our findings support ‘technical intelligence’ hypotheses in linking technical innovation to encephalization in the restricted set of primate lineages where technical innovation has been reported. Our findings also provide support for a broad co-evolving complex of brain, behaviour, life-history, social and dietary variables, providing secondary support for social and ecological intelligence hypotheses. The ability to gain access to difficult-to-extract, but potentially nutrient-rich, resources through tool use may have conferred on some primates adaptive advantages, leading to selection for brain circuitry that underlies technical proficiency. 相似文献
54.
Rhizobacterial Community Structures Associated with Native Plants Grown in Chilean Extreme Environments 总被引:1,自引:0,他引:1
55.
Changes in butterfly distributions and species assemblages on a Neotropical mountain range in response to global warming and anthropogenic land use 下载免费PDF全文
56.
57.
Heme Biosynthetic Pathway is Functionally Linked to Adipogenesis via Mitochondrial Respiratory Activity 下载免费PDF全文
58.
Simm A Nass N Bartling B Hofmann B Silber RE Navarrete Santos A 《Biological chemistry》2008,389(3):257-265
Life span in individual humans is very heterogeneous.Thus, the ageing rate, measured as the decline of functional capacity and stress resistance, is different in every individual. There have been attempts made to analyse this individual age, the so-called biological age, in comparison to chronological age. Biomarkers of ageing should help to characterise this biological age and, as age is a major risk factor in many degenerative diseases,could be subsequently used to identify individuals at high risk of developing age-associated diseases or disabilities.Markers based on oxidative stress, protein glycation,inflammation, cellular senescence and hormonal deregulation are discussed. 相似文献
59.
Palomar AR Larios BN De Sánchez VC Pérez LM López Fde L Flores G Gómez-Villalobos Mde J 《Neurochemical research》2011,36(3):399-405
Dopamine transporter (DAT) is a membrane protein that it is a marker for dopaminergic neurons. In the present work, throught
Western blot and autoradiographic studies with a selective ligand for DAT ([3H] WIN-35428) and noradrenaline transporter (NET) ([3H] Nisoxetine), we search the expression and distribution of DAT in comparison with NET, in cardiac tissue of guinea pig in
order to support the presence of dopaminergic nerve cells into the heart. Expression of DAT, and NET were evidenced by a bands
of 75 and 54 kDa, respectively in the heart. Binding for DAT and NET were found in the four cardiac chambers. However, DAT
show heterogeneous distribution with binding in right atria and in both ventricles, whereas NET show homogenous distribution
in the four cardiac chambers. The results show the expression of DAT in cardiac tissues with a different distribution compared
with NET, being an evidence for the presence of dopaminergic nerve cells into the heart. 相似文献