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991.
992.
Protective T cell immunity against malaria liver stage after vaccination with live sporozoites under chloroquine treatment 总被引:8,自引:0,他引:8
Belnoue E Costa FT Frankenberg T Vigário AM Voza T Leroy N Rodrigues MM Landau I Snounou G Rénia L 《Journal of immunology (Baltimore, Md. : 1950)》2004,172(4):2487-2495
In this study we present the first systematic analysis of the immunity induced by normal Plasmodium yoelii sporozoites in mice. Immunization with sporozoites, which was conducted under chloroquine treatment to minimize the influence of blood stage parasites, induced a strong protection against a subsequent sporozoite and, to a lesser extent, against infected RBC challenges. The protection induced by this immunization protocol proved to be very effective. Induction of this protective immunity depended on the presence of liver stage parasites, as primaquine treatment concurrent with sporozoite immunization abrogated protection. Protection was not found to be mediated by the Abs elicited against pre-erythrocytic and blood stage parasites, as demonstrated by inhibition assays of sporozoite penetration or development in vitro and in vivo assays of sporozoite infectivity or blood stage parasite development. CD4(+) and CD8(+) T cells were, however, responsible for the protection through the induction of IFN-gamma and NO. 相似文献
993.
994.
Detection and characterization of SNPs useful for identity control and parentage testing in major European dairy breeds 总被引:2,自引:0,他引:2
Werner FA Durstewitz G Habermann FA Thaller G Krämer W Kollers S Buitkamp J Georges M Brem G Mosner J Fries R 《Animal genetics》2004,35(1):44-49
We propose the use of single nucleotide polymorphisms (SNPs) instead of polymorphic microsatellite markers for individual identification and parentage control in cattle. To this end, we present an initial set of 37 SNP markers together with a gender-specific SNP for identity control and parentage testing in the Holstein, Fleckvieh and Braunvieh breeds. To obtain suitable SNPs, a total of 91.13 kb of random genomic DNA was screened yielding 531 SNPs. These, and 43 previously identified SNPs, were subjected to the following selection criteria: (1) the frequency of the minor allele must be larger than 0.1 in at least two of the three examined breeds, and (2) markers should not be linked closely. Allele frequencies were estimated by analysing sequencing traces of pooled DNA or by genotyping individual DNA samples. The selected SNP loci were physically mapped by radiation hybrid mapping or by fluorescence in situ hybridization, and tested against the neutral mutation hypothesis. The presented marker set theoretically allows probabilities of identity less than 10(-13) for individual verification and exclusion powers exceeding 99.99% for parentage testing. 相似文献
995.
996.
In a search for new inhibitors that exploit 5'-6' 'hydrolytic activity' of AdoHcy hydrolase, a new series of haloethyl and dihalocyclopropyl esters 2-3 were designed and their interaction with the enzyme studied. Incubation of the enzyme with 2-3 resulted in time- and concentration-dependent inactivation of AdoHcy hydrolase as well as almost total depletion of its NAD(+) content. Further results indicated that the 'oxidative' but not the 'hydrolytic' activity was involved in the inactivation process. 相似文献
997.
Insecticide resistance: a silent base prediction 总被引:3,自引:0,他引:3
Weill M Berthomieu A Berticat C Lutfalla G Nègre V Pasteur N Philips A Leonetti JP Fort P Raymond M 《Current biology : CB》2004,14(14):R552-R553
998.
Rotavirus mRNAs are capped but not polyadenylated, and viral proteins are translated by the cellular translation machinery. This is accomplished through the action of the viral nonstructural protein NSP3, which specifically binds the 3' consensus sequence of viral mRNAs and interacts with the eukaryotic translation initiation factor eIF4G I. To further our understanding of the role of NSP3 in rotavirus replication, we looked for other cellular proteins capable of interacting with this viral protein. Using the yeast two-hybrid assay, we identified a novel cellular protein-binding partner for rotavirus NSP3. This 110-kDa cellular protein, named RoXaN (rotavirus X protein associated with NSP3), contains a minimum of three regions predicted to be involved in protein-protein or nucleic acid-protein interactions. A tetratricopeptide repeat region, a protein-protein interaction domain most often found in multiprotein complexes, is present in the amino-terminal region. In the carboxy terminus, at least five zinc finger motifs are observed, further suggesting the capacity of RoXaN to bind other proteins or nucleic acids. Between these two regions exists a paxillin leucine-aspartate repeat (LD) motif which is involved in protein-protein interactions. RoXaN is capable of interacting with NSP3 in vivo and during rotavirus infection. Domains of interaction were mapped and correspond to the dimerization domain of NSP3 (amino acids 163 to 237) and the LD domain of RoXaN (amino acids 244 to 341). The interaction between NSP3 and RoXaN does not impair the interaction between NSP3 and eIF4G I, and a ternary complex made of NSP3, RoXaN, and eIF4G I can be detected in rotavirus-infected cells, implicating RoXaN in translation regulation. 相似文献
999.
Baquet G Guinhouya C Dupont G Nourry C Berthoin S 《Journal of strength and conditioning research / National Strength & Conditioning Association》2004,18(4):708-713
The aim of this study was to analyze the effects of a 7-week interval-training program on different aspects of physical fitness in children who were 8-11 years old. Forty-six boys and 54 girls (9.7 +/- 0.8 years) were divided into an experimental group and a control group. The 2 groups performed selected tests from the European physical fitness test battery before and after training. Training consisted of 2 specific 30-minute sessions per week of short high-intensity, intermittent-running aerobic exercises at velocities ranging from 100-130% of maximal aerobic speed. After training, the experimental group demonstrated a significant improvement in the standing broad jump (9.6%, p < 0.001, F = 12.9) and 20-meter shuttle run (5.4%, p < 0.001, F = 14.4), whereas for the control group, no significant changes were observed. It was concluded that a high-intensity, intermittent-running program improved children's aerobic performance and explosive strength. 相似文献
1000.
Damien?BanasEmail author Patrick?Grillas Isabelle?Auby Fran?ois?Lescuyer Eric?Coulet Jean-Claude?Moreteau Bertrand?Millet 《Hydrobiologia》2005,551(1):3-16
High frequency water sampling in the wind-exposed Vaccarès lagoon revealed frequent and rapid changes in suspended solid (SS)
concentrations in the water column. SS concentrations, sometimes higher than 800 mg l−1, were significantly correlated with antecedent wind conditions. Mean wind velocity during the 5–33 h before water sampling
or maximal wind velocity during the previous 8.5–22 h were good predictors of SS concentrations in the water column. Underwater
irradiance at canopy level was modeled (r2 = 0.66, n = 7584) using the SS calculated from the relationship between SS and antecedent mean wind velocity and the surface irradiance
data measured at the weather station close to the study site. On the other hand, we have shown that in this wind-exposed lagoon,
mean underwater irradiance can not be effectively estimated using infrequent measurements of the optical properties of water. 相似文献