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71.
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Andrea E. Glassmire Casey Philbin Lora A. Richards Christopher S. Jeffrey Joshua S. Snook Lee A. Dyer 《Ecology letters》2019,22(2):332-341
Phytochemical traits are a key component of plant defense theory. Chemical ecology has been biased towards studying effects of individual metabolites even though effective plant defenses are comprised of diverse mixtures of metabolites. We tested the phytochemical landscape hypothesis, positing that trophic interactions are contingent upon their spatial location across a phytochemically diverse landscape. Specifically, intraspecific phytochemical changes associated with vertical strata in forests were hypothesised to affect herbivore communities of the neotropical shrub Piper kelleyi Tepe (Piperaceae). Using a field experiment, we found that phytochemical diversity increased with canopy height, and higher levels of phytochemical diversity located near the canopy were characterised by tradeoffs between photoactive and non‐photoactive biosynthetic pathways. For understory plants closer to the ground, phytochemical diversity increased as direct light transmittance decreased, and these plants were characterised by up to 37% reductions in herbivory. Our results suggest that intraspecific phytochemical diversity structures herbivore communities across the landscape, affecting total herbivory. 相似文献
73.
Xing C Sestak AL Kelly JA Nguyen KL Bruner GR Harley JB Gray-McGuire C 《Human genetics》2007,120(5):623-631
Systemic lupus erythematosus (SLE) is a systemic autoimmune disease characterized by both population and phenotypic heterogeneity.
Our group previously identified linkage to SLE at 4p16 in European Americans (EA). In the present study we replicate this
linkage effect in a new cohort of 76 EA families multiplex for SLE by model-free linkage analysis. Using densely spaced microsatellite
markers in the linkage region, we have localized the potential SLE susceptibility gene(s) to be telomeric to the marker D4S2928
by haplotype construction. In addition, marker D4S394 showed marginal evidence of linkage disequilibrium with the putative
disease locus by the transmission disequilibrium test and significant evidence of association using a family-based association
approach as implemented in the program ASSOC. We also performed both two-point and multipoint model-based analyses to characterize
the genetic model of the potential SLE susceptibility gene(s), and the lod scores both maximized under a recessive model with
penetrances of 0.8. Finally, we performed a genome-wide scan of the total 153 EA pedigrees and evaluated the possibility of
interaction between linkage signals at 4p16 and other regions in the genome. Fourteen regions on 11 chromosomes (1q24, 1q42,
2p11, 2q32, 3p14.2, 4p16, 5p15, 7p21, 8p22, 10q22, 12p11, 12q24, 14q12, 19q13) showed evidence of linkage, among which, signals
at 2p11, 12q24 and 19q13 also showed evidence of interaction with that at 4p16. These results provide important additional
information about the SLE linkage effect at 4p16 and offer a unique approach to uncovering susceptibility loci involved in
complex human diseases. 相似文献
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75.
Peinelt C Vig M Koomoa DL Beck A Nadler MJ Koblan-Huberson M Lis A Fleig A Penner R Kinet JP 《Nature cell biology》2006,8(7):771-773
Depletion of intracellular calcium stores activates store-operated calcium entry across the plasma membrane in many cells. STIM1, the putative calcium sensor in the endoplasmic reticulum, and the calcium release-activated calcium (CRAC) modulator CRACM1 (also known as Orai1) in the plasma membrane have recently been shown to be essential for controlling the store-operated CRAC current (I(CRAC)). However, individual overexpression of either protein fails to significantly amplify I(CRAC). Here, we show that STIM1 and CRACM1 interact functionally. Overexpression of both proteins greatly potentiates I(CRAC), suggesting that STIM1 and CRACM1 mutually limit store-operated currents and that CRACM1 may be the long-sought CRAC channel. 相似文献
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77.
The main aim of this work was to assess the multi-task role of ferritin(Ft)in the oxidative metabolism of soybean(Glycine max).Soybean seeds incubated for 24 h yielded 41 ± 5 μg Ft/g fresh weight.The rate of in vitro incorporation of iron(Fe)into Ft was tested by supplementing the reaction medium with physiological Fe chelators.The control rate,observed in the presence of 100 μM Fe,was not significantly different from the values observed in the presence of 100 μM Fe-his.However,it was significantly higher in the presence of 100 μM Fe-citrate(approximately 4.5-fold)or of 100 μM Fe-ATP(approximately 14-fold).Moreover,a substantial decrease in the Trp-dependent fluorescence of the Ft protein was determined during Fe uptake from Fe-citrate,as compared with the control.On the other hand,Ft addition to homogenates from soybean embryonic axes reduced endogenously generated ascorbyl radical,according to its capacity for Fe uptake.The data presented here suggest that Ft could be involved in the generation of free radicals,such as hydroxyl radical,by Fe-catalyzed reactions.Moreover,the scavenging of these radicals by Ft itself could then lead to protein damage.However,Ft could also prevent cellular damage by the uptake of catalytically active Fe. 相似文献
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