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951.
Andrew Buskell 《Biology & philosophy》2016,31(3):435-446
Morin has written a rich and valuable book. Its main aim is to isolate the factors involved in maintaining behavioural lineages over time, and to understand how these factors might interact. In doing so, it takes issue with the abstract and idealised models and arguments of dual-inheritance theorists, which are alleged in this account to rely on an overly simplistic notion of imitative learning. Morin’s book is full of ethnographic, anthropological, and psychological research, and there is much to commend in it. However, Morin’s arguments against the dual-inheritance theorists are less convincing when put under scrutiny, and his positive picture which includes appeals to ostensive communication, intrinsic appeal and cultural attraction has some difficulties. I argue that when we contrast dual-inheritance theorists and Morin, we find that there may be fewer differences and greater commonalities than Morin’s book might suggest. 相似文献
952.
Torben Greve 《Acta veterinaria Scandinavica》2004,45(Z1):S13
Xenotransplantation of organs from the large domestic species will only be successful if the donor animals have been genetically modified, in particular regarding the α-Gal epitope, certain human complements (CD55 and CD59) and/or H-transferase. This requires, among other things, major embryo-technological efforts, and the rate of success is still far from an acceptable level in the domestic species. It is currently poor, but the progress is very good. In this brief review certain embryo-technological problems will be addressed with the focus on the pig as potential organ donor. In addition, certain views of the Danish ad hoc Committee on Gene Technology on xenotransplantation will be presented in this context as they are supposed to mirror the concern and the views of the issues important for the public and each individual. 相似文献
953.
Molecular tools were used to evaluate the hybrid status of a specimen with intermediate colour pattern between Halichoeres bivittatus and Halichoeres garnoti from Belize. Phylogenetic analyses of the two species, eight Halichoeres species from new and old world lineages and two outgroups showed that the study species are closely related and that H. garnoti is the maternal contributor to the putative hybrid specimen, based on partial mitochondrial COI data. Direct sequencing of
Intron 1 of the nuclear ribosomal protein S7 identified H. bivittatus as sister to H. garnoti with the putative hybrid specimen in an intermediate position, due to heterozygosity at nucleotides alternatively fixed in
the two putative parent species. This is consistent with the hybrid status of the specimen, with parental contributions from
both H. garnoti and H. bivittatus. These results, combined with no evidence of introgression between the two parent species (based on the mtDNA and the single
investigated nuclear marker) and the biogeography and ecology of these species suggests that this is a rare event with minimal
evolutionary implications. 相似文献
954.
Postexercise protein supplementation improves health and muscle soreness during basic military training in Marine recruits. 总被引:1,自引:0,他引:1
Paul J Flakoll Tom Judy Kim Flinn Christopher Carr Scott Flinn 《Journal of applied physiology》2004,96(3):951-956
Elevated postexercise amino acid availability has been demonstrated to enhance muscle protein synthesis acutely, but the long-term impact of postexercise protein supplementation on variables such as health, muscle soreness, and function are unclear. Healthy male US Marine recruits from six platoons (US Marine Corps Base, Parris Island, SC; n = 387; 18.9 +/- 0.1 yr, 74.7 +/- 1.1 kg, 13.8 +/- 0.4% body fat) were randomly assigned to three treatments within each platoon. Nutrients supplemented immediately postexercise during the 54-day basic training were either placebo (0 g carbohydrate, 0 g protein, 0 g fat), control (8, 0, 3), or protein supplement (8, 10, 3). Subjects and observers making measurements and data analysis were blinded to subject groupings. Compared with placebo and control groups, the protein-supplemented group had an average of 33% fewer total medical visits, 28% fewer visits due to bacterial/viral infections, 37% fewer visits due to muscle/joint problems, and 83% fewer visits due to heat exhaustion. Recruits experiencing heat exhaustion had greater body mass, lean, fat, and water losses. Muscle soreness immediately postexercise was reduced by protein supplementation vs. placebo and control groups on both days 34 and 54. Postexercise protein supplementation may not only enhance muscle protein deposition but it also has significant potential to positively impact health, muscle soreness, and tissue hydration during prolonged intense exercise training, suggesting a potential therapeutic approach for the prevention of health problems in severely stressed exercising populations. 相似文献
955.
Dominik Karch Keun-Sun Kim Katarzyna Wochner Heike Philippi Joachim Pietz Hartmut Dickhaus 《Journal of biomechanics》2010,43(9):1844-1848
In motion capture applications using electromagnetic tracking systems the process of anatomical calibration associates the technical frames of sensors attached to the skin with the human anatomy. Joint centers and axes are determined relative to these frames. A change of orientation of the sensor relative to the skin renders this calibration faulty. This sensitivity regarding sensor displacement can turn out to be a serious problem with movement recordings of several minutes duration. We propose the “dislocation distance” as a novel method to quantify sensor displacement and to detect gradual and sudden changes of sensor orientation. Furthermore a method to define a so called fixed technical frame is proposed as a robust reference frame which can adapt to a new sensor orientation on the skin. The proposed methods are applied to quantify the effects of sensor displacement of 120 upper and lower limb movement recordings of newborns revealing the need for a method to compensate for sensor displacement. The reliability of the fixed technical frame is quantified and it is shown that trend and dispersion of the dislocation distance can be significantly reduced. A working example illustrates the consequences of sensor displacement on derived angle time series and how they are avoided using the fixed technical frame. 相似文献
956.
957.
958.
Gerald Busch 《Bioenergy Research》2012,5(3):584-605
Based on regional stakeholder preferences and planning guidelines as allocation criteria for SRC, this study aims at providing
a transparent approach to evaluate multiple environmental effects and the regional significance of SRC systems. Using the
example of two poplar SRC-systems (4-year rotation, 9-year rotation) the potential effects on ground water supply, wind erosion,
and biodiversity aspects are evaluated in comparison to arable land for two selected municipalities in the district of Uelzen,
Germany. Building on fuzzy membership functions and simple fuzzy-logic rules, the qualitative multi-criteria assessment is
transparent and easily to adapt. This approach is transferable to other regions and spatial levels, since it derives from
commonly available data and scientific evidence. Results show that implementation of SRC could provide multiple beneficial
environmental effects, especially in areas with low landscape heterogeneity. The tools provided allow for a multi-criteria
evaluation of environmental effects, and reveal the sensitivity to distinct allocation patterns. Physiographical conditions
of the study area implicate a preference for mini-SRC systems. This is supported by smaller decline of annual deep percolation
water compared to maxi-SRC. On average, decline in groundwater recharge of mini-SRC (92mm a−1) is comparable to irrigated arable land (80mm a−1), which is common practice in the study area. Currently, the utilization of beneficial environmental SRC effects is quite
limited, since only 3 % of arable land is suitable for SRC implementation regarding farmers’ preferences for SRC allocation.
Allocation preferences could however change substantially with increasing incentives for SRC, e.g., due to regional bioenergy
schemes or “Greening” initiatives within the European Common Agricultural Policy, which is to be reformed by 2013. 相似文献
959.
Paul Bangirana Peter Allebeck Michael J Boivin Chandy C John Connie Page Anna Ehnvall Seggane Musisi 《BMC neurology》2011,11(1):96
Background
Infection with severe malaria in African children is associated with not only a high mortality but also a high risk of cognitive deficits. There is evidence that interventions done a few years after the illness are effective but nothing is known about those done immediately after the illness. We designed a study in which children who had suffered from severe malaria three months earlier were enrolled into a cognitive intervention program and assessed for the immediate benefit in cognitive, academic and behavioral outcomes. 相似文献960.
To gain insight into the molecular mechanism of odorant receptors (ORs) in Drosophila species, we developed a Quantitative Structure Activity Relationship (QSAR) model that predicts experimentally measured electrophysiological activities between 24 D. melanogaster ORs and 108 odorants. Although the model is limited by the tested odorants,analyzing the model allowed dissection of specific topological and chemical properties necessary for an odorant to elicit excitatory or inhibitory receptor response. Linear odorants with five to eight nonhydrogen atoms at the main chain and hydrogen‐bond acceptor and/or hydrogen‐bond donor at its ends were found to stimulate strong excitatory response. A comparative sequence analysis of 90 ORs in 15 orthologous groups identified 15 putative specificity‐determining residues (SDRs) and 15 globally conserved residues that we postulate as functionally key residues. Mapping to a model of secondary structure resulted in 14 out of 30 key residues locating to the transmembrane (TM) domains. Twelve residues, including six SDRs and six conserved residues, are located at the extracellular halves of the TM domains. Combining the evidence from the QSAR modeling and the comparative sequence analysis, we hypothesize that the Drosophila ORs accept odorants into a binding pocket located on the extracellular halves of its TM domains. The QSAR modeling suggests that the binding pocket is around 15 Å in depth and about 6 Å in width. Twelve mainly polar or charged key residues, both SDRs and conserved, are located inthis pocket and postulated to distinguish docked odorants via primarily geometry fitting and hydrogen‐bond interaction. Proteins 2010. © 2009 Wiley‐Liss, Inc. 相似文献