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991.
Andreas Zankl Emma?L. Duncan Paul?J. Leo Graeme?R. Clark Evgeny?A. Glazov Marie-Claude Addor Troels Herlin Chong?Ae Kim Bruno?P. Leheup Jim McGill Steven McTaggart Stephen Mittas Anna?L. Mitchell Geert?R. Mortier Stephen?P. Robertson Marie Schroeder Paulien Terhal Matthew?A. Brown 《American journal of human genetics》2014,94(4):643
992.
993.
Predicted insect diversity declines under climate change in an already impoverished region 总被引:1,自引:0,他引:1
Dirk Maes Nicolas Titeux Joaquín Hortal Anny Anselin Kris Decleer Geert De Knijf Violaine Fichefet Miska Luoto 《Journal of Insect Conservation》2010,14(5):485-498
Being ectotherms, insects are predicted to suffer more severely from climate change than warm-blooded animals. We forecast
possible changes in diversity and composition of butterflies, grasshoppers and dragonflies in Belgium under increasingly severe
climate change scenarios for the year 2100. Two species distribution modelling techniques (Generalised Linear Models and Generalised
Additive Models), were combined via a conservative version of the ensemble forecasting strategy to predict present-day and
future species distributions, considering the species as potentially present only if both modelling techniques made such a
prediction. All models applied were fair to good, according to the AUC (area under the curve of the receiver operating characteristic
plot), sensitivity and specificity model performance measures based on model evaluation data. Butterfly and grasshopper diversity
were predicted to decrease significantly in all scenarios and species-rich locations were predicted to move towards higher
altitudes. Dragonfly diversity was predicted to decrease significantly in all scenarios, but dragonfly-rich locations were
predicted to move upwards only in the less severe scenarios. The largest turnover rates were predicted to occur at higher
altitudes for butterflies and grasshoppers, but at intermediate altitudes for dragonflies. Our results highlight the challenge
of building conservation strategies under climate change, because the changes in the sites important for different groups
will not overlap, increasing the area needed for protection. We advocate that possible conservation and policy measures to
mitigate the potentially strong impacts of climate change on insect diversity in Belgium should be much more pro-active and
flexible than is the case presently. 相似文献
994.
V. Stalin Raj Saskia L. Smits Lisette B. Provacia Judith M. A. van den Brand Lidewij Wiersma Werner J. D. Ouwendijk Theo M. Bestebroer Monique I. Spronken Geert van Amerongen Peter J. M. Rottier Ron A. M. Fouchier Berend Jan Bosch Albert D.M.E. Osterhaus Bart L. Haagmans 《Journal of virology》2014,88(3):1834-1838
Middle East respiratory syndrome coronavirus (MERS-CoV) replicates in cells of different species using dipeptidyl peptidase 4 (DPP4) as a functional receptor. Here we show the resistance of ferrets to MERS-CoV infection and inability of ferret DDP4 to bind MERS-CoV. Site-directed mutagenesis of amino acids variable in ferret DPP4 thus revealed the functional human DPP4 virus binding site. Adenosine deaminase (ADA), a DPP4 binding protein, competed for virus binding, acting as a natural antagonist for MERS-CoV infection. 相似文献
995.
Krijn Baptist Trimbos Joyce Broekman Rosemarie Kentie Cees J. M. Musters Geert R. de Snoo 《Journal of Ornithology》2009,150(4):915-920
In the context of population genetic research, a faster and less invasive method of DNA sampling would allow large-scale assessments
of genetic diversity and genetic differentiation with the help of volunteer observers. The aim of this study was to investigate
the usefulness of eggshell membranes as a DNA source for population genetic research, by addressing eggshell membrane DNA
quality, degeneration and cross-contamination. To this end, a comparison was made with blood-derived DNA samples. We have
demonstrated 100% successful DNA extraction from post-hatched Black-tailed Godwit (Limosa limosa) eggshell membranes as well as from blood samples. Using 11 microsatellite loci, DNA amplification success was 99.1% for
eggshell membranes and 97.7% for blood samples. Genetic information within eggshell membrane DNA in comparison to blood DNA
was not affected (F
ST = −0.01735, P = 0.999) by degeneration or possible cross-contamination. Furthermore, neither degeneration nor cross-contamination was apparent
in total genotypic comparison of eggshell membrane DNA and blood sample DNA. Our research clearly illustrates that eggshell
membranes can be used for population genetic research. 相似文献
996.
Acardiac twinning: High resolution three‐dimensional reconstruction of a low resistance case 下载免费PDF全文
997.
Summary The enzyme acetate kinase (EC 2.7.2.1) was purified fromDesulfovibrio vulgaris by a combination of ammonium sulfate precipitation, hydroxyl-apatite and dye-affinity chromatography. An overall-purification factor of 15 was obtained resulting in a specific activity of 24 U/mg protein. The purified enzyme was immobilized on differently derivatized controlled pore glass beads. 相似文献
998.
Coen Van Den Berg Geert J. M. Van Snik Jos G. M. Van Den Boogaart Ferdinand A. Sibbing Jan W. M. Osse 《Journal of morphology》1994,219(1):73-87
The chimaeroid holocephalian fishes are distinguished among extant chondrichthyans by the possession of three pairs of tooth plates, evergrowing and partially hypermineralized, that are not shed and replaced like the teeth of living elasmobranchs. Although derivation of the chimaeroid tooth plate from the fusion of members of a plesiomorphic chondrichthyan tooth family has been proposed, evidence for this hypothesis has been lacking. A new analysis of the development and structure of the tooth plates in Callorhinchus milii (Holocephali, Chimaeriformes) reveals the compound nature of the tooth plates in a chimaeroid fish. Each tooth plate consists of an oral and aboral territory that form independently in the embryo and maintain separate growth surfaces through life. The descending lamina on the aboral surface of the tooth plate demarcates the growth surface of the aboral territory. Comparison with the tooth plates of Chimaera monstrosa indicates that compound tooth plates may be a feature of all chimaeroids in which a descending lamina is present. The tooth plates in these fishes represent the fusion of two members of a reduced tooth family. The condition of the tooth plates in C. milii is plesiomorphic for chimaeroids and is of evolutionary significance in that it provides further evidence to support a lyodont dentition in chimaeroid fishes similar to that found in other chondrichthyans. © 1994 Wiley-Liss, Inc. 相似文献
999.
Vaiva Deltuvaite-Thomas Johan Verbeeck Tomasz Burzykowski Marc Buyse Christophe Tournigand Geert Molenberghs Olivier Thas 《Biometrical journal. Biometrische Zeitschrift》2023,65(2):2100354
The method of generalized pairwise comparisons (GPC) is an extension of the well-known nonparametric Wilcoxon–Mann–Whitney test for comparing two groups of observations. Multiple generalizations of Wilcoxon–Mann–Whitney test and other GPC methods have been proposed over the years to handle censored data. These methods apply different approaches to handling loss of information due to censoring: ignoring noninformative pairwise comparisons due to censoring (Gehan, Harrell, and Buyse); imputation using estimates of the survival distribution (Efron, Péron, and Latta); or inverse probability of censoring weighting (IPCW, Datta and Dong). Based on the GPC statistic, a measure of treatment effect, the “net benefit,” can be defined. It quantifies the difference between the probabilities that a randomly selected individual from one group is doing better than an individual from the other group. This paper aims at evaluating GPC methods for censored data, both in the context of hypothesis testing and estimation, and providing recommendations related to their choice in various situations. The methods that ignore uninformative pairs have comparable power to more complex and computationally demanding methods in situations of low censoring, and are slightly superior for high proportions (>40%) of censoring. If one is interested in estimation of the net benefit, Harrell's c index is an unbiased estimator if the proportional hazards assumption holds. Otherwise, the imputation (Efron or Peron) or IPCW (Datta, Dong) methods provide unbiased estimators in case of proportions of drop-out censoring up to 60%. 相似文献
1000.
Shanshan Li Jessica De La Cruz Steven Hutchens Somshuvra Mukhopadhyay Zachary K. Criss Rohit Aita Oscar Pellon-Cardenas Joseph Hur Patricia Soteropoulos Seema Husain Puneet Dhawan Lieve Verlinden Geert Carmeliet James C. Fleet Noah F. Shroyer Michael P. Verzi Sylvia Christakos 《Molecular and cellular biology》2021,41(1)