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891.
Patellofemoral pain (PFP) is a common condition that occurs more frequently in females. Anatomical, hormonal and neuromuscular factors have been proposed to contribute to the increased incidence of PFP in females, with neuromuscular factors considered to be of particular importance. This cross-sectional study aimed to evaluate differences in the neuromotor control of the knee and hip muscles between genders and to investigate whether clinical measures of hip rotation range and strength were associated with EMG measures of hip and thigh motor control. Twenty-nine (16 female and 13 male) asymptomatic participants completed a visual choice reaction-time stair stepping task. EMG activity was recorded from vastus medialis oblique, vastus lateralis, anterior and posterior gluteus medius muscles. In addition hip rotation range of motion and hip external rotation, abduction and trunk strength were assessed. There were no differences in the timing or peak of EMG activation of the vasti or gluteus medius muscle between genders during the stepping task. There were however significant associations between EMG measures of motor control of the vasti and hip strength in both females and males. These findings are suggestive of a link between hip muscle control and vasti neuromotor control. 相似文献
892.
Ainara Cortés-Avizanda Nuria Selva Martina Carrete José A. Donázar 《Basic and Applied Ecology》2009,10(3):265-272
Carcasses of large herbivores are pulsed resources whose impact on animal communities and ecological processes is poorly understood. In temperate forests, long-lasting ungulate carcasses are a prime resource for many species of birds and mammals during winter. Facultative carrion-eaters also consume live prey, thus potentially leading to unexpected secondary effects on populations of species not directly linked to carcass exploitation. By snow-tracking and direct observations we investigated in Bia?owie?a Forest (E. Poland) whether large ungulate carcasses elicit spatial responses in facultative scavengers and their prey. We found that in the vicinity of carcass sites the probability of the presence of common ravens Corvus corax, jays Garrulus glandarius and red foxes Vulpes vulpes increased significantly. Indeed, large groups of the two bird species were exclusively found in those places. Because of these aggregations, the probability of predator–prey encounters (red foxes and brown hares Lepus europaeus) was significantly higher near carcass sites. Accordingly, the abundance of hares and other live prey such as red squirrels Sciurus vulgaris decreased at their vicinities, probably as a consequence of direct killing and/or predator avoidance. This study provides the first evidence of carrion pulses permeating into apparently distant trophic levels, such as herbivores, via facultative scavengers, thus highlighting some unnoticed but relevant effects of carrion resources on community structure. 相似文献
893.
Reconstruction of the eyelids can range from simple repair to the integration of multiple complex procedures. Knowledge of eyelid anatomy, adequate preoperative planning, and meticulous surgical technique will optimize the anatomical and functional result. The purpose of this article is to review the relevant anatomy for eyelid reconstruction, to simplify defect analysis and preoperative planning, and to provide options for reconstruction of this complex area. 相似文献
894.
Fiona K. Y. Wong Maggie C. Y. Lau Donnabella C. Lacap Jonathan C. Aitchison Donald A. Cowan Stephen B. Pointing 《Microbial ecology》2010,59(4):689-699
The morphology of endolithic colonization in a limestone escarpment and surrounding rocky debris (termed float) at a high-altitude arid site in central Tibet was documented using scanning electron microscopy. Putative lichenized structures and extensive coccoid bacterial colonization were observed. Absolute and relative abundance of rRNA gene signatures using real-time quantitative polymerase chain reaction and phylogenetic analysis of environmental phylotypes were used to characterize community structure across all domains. Escarpment endoliths were dominated by eukaryotic phylotypes suggestive of lichenised associations (a Trebouxia lichen phycobiont and Leptodontidium lichen mycobiont), whereas float endoliths were dominated by bacterial phylotypes, including the cyanobacterium Chroococcidiopsis plus several unidentified beta proteobacteria and crenarchaea. Among a range of abiotic variables tested, ultraviolet (UV) transmittance by rock substrates was the factor best able to explain differences in community structure, with eukaryotic lichen phylotypes more abundant under conditions of greater UV-exposure compared to prokaryotes. Variously pigmented float rocks did not support significantly different communities. Estimates of in situ carbon fixation based upon 14C radio-labelled bicarbonate uptake indicated endolithic productivity of approximately 2.01 g C/m2/year?1, intermediate between estimates for Antarctic and temperate communities. 相似文献
895.
896.
Hong Wei Wang Hyuk Jin Kwon Won Cheol Yim Sung Don Lim Jun-Cheol Moon Byung-Moo Lee Yong Weon Seo Wook Kim Cheol Seong Jang 《Genetica》2010,138(8):843-852
Previously, the wheat non-specific lipid transfer proteins (TaLTP), members of a small multigene family, were reported to
evidence a complex pattern of expression regulation. In order to assess further the expression diversity of the TaLTP genes, we have attempted to evaluate their expression profiles in responses to abiotic stresses, using semi-quantitative
RT-PCR. The expression profiles generated herein revealed that the TaLTP genes in group A evidenced highly similar responses against abiotic stresses, whereas differential expression patterns among
genes in each group were also observed. A total of seven promoters were fused to a GUS reporter gene and the recombinants
were introduced into Arabidopsis, while three promoters evidenced non-detectible GUS activity. The promoters of TaLTP1, TaLTP7, and TaLTP10 included in group A drove strong expressions during plant development with overlapping patterns, in large part, but also
exhibited distinct expression pattern, thereby suggesting subfunctionalization processing over evolutionary time. However,
only trace expression in cotyledons, young emerged leaves, and epidermal cell layers of flower ovaries was driven by the promoter
of TaLTP3 of group B. These results indicate that their distinct physiological functions appear to be accomplished by a subfunctionalization
process involving degenerative mutations in regulatory regions. 相似文献
897.
898.
899.
The Novel Weapons Hypothesis predicts that invasive plants excel in their new ranges because they produce novel metabolites
to which native species possess little resistance. We examined the novelty of the phytochemistry of the Eurasian invader,
Alliaria petiolata, in North America by comparing its phytochemical profile with those of closely related Brassicaceae native to North America.
We examined the profile and/or concentrations of glucosinolates, alliarinoside, flavonoids, cyanide, and trypsin inhibitors
in cauline leaves of field-collected A. petiolata, Arabis laevigata, Cardamine concatenata, C. bulbosa, and C. douglassii. Cyanide and the glucosinolates and flavonoids produced by A. petiolata were detected only in A. petiolata. Trypsin inhibitor activity was highest in A. laevigata, intermediate in the Cardamine species, and lowest in A. petiolata. The phytochemical profile of A. petiolata was distinct from those of four closely related and/or abundant Brassicaceaeous species native to North America, providing
support for the Novel Weapons Hypothesis. 相似文献
900.
Ren Yuan Taishi Nagao Peter D Paré James C Hogg Don D Sin Mark W Elliott Leanna Loy Li Xing Steven E Kalloger John C English John R Mayo Harvey O Coxson 《Respiratory research》2010,11(1):153