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941.
Full-face masks, worn by skilled actors in the Noh tradition, can induce a variety of perceived expressions with changes in head orientation. Out-of-plane rotation of the head changes the two-dimensional image characteristics of the face which viewers may misinterpret as non-rigid changes due to muscle action. Three experiments with Japanese and British viewers explored this effect. Experiment 1 confirmed a systematic relationship between vertical angle of view of a Noh mask and judged affect. A forward tilted mask was more often judged happy, and one backward tilted more often judged sad. This effect was moderated by culture. Japanese viewers ascribed happiness to the mask at greater degrees of backward tilt with a reversal towards sadness at extreme forward angles. Cropping the facial image of chin and upper head contour reduced the forward-tilt reversal. Finally, the relationship between head tilt and affect was replicated with a laser-scanned human face image, but with no cultural effect. Vertical orientation of the head changes the apparent disposition of facial features and viewers respond systematically to these changes. Culture moderates this effect, and we discuss how perceptual strategies for ascribing expression to familiar and unfamiliar images may account for the differences.  相似文献   
942.
943.
The molecular cloning of a cDNA coding for human gastric lipase and its expression in yeast is described. A lipase present in human gastric aspirates was purified and its N-terminal amino-acid sequence was determined. This was found to be homologous with the N-terminal sequence of rat lingual lipase. A cDNA library was constructed from mRNA isolated from human stomach tissue and probed with cloned rat lingual lipase DNA. One clone, pGL17, consisting of approximately 1450 base-pairs, contained the entire coding sequence for a human gastric lipase. The amino-acid sequence from the isolated protein and the DNA sequence obtained from the cloned gene indicated that human gastric lipase consists of a 379 amino acid polypeptide with an unglycosylated Mr of 43,162. Human gastric lipase and rat lingual lipase amino-acid sequences were closely homologous but were unrelated to porcine pancreatic lipase apart from a 6 amino-acid sequence around the essential Ser-152 of porcine pancreatic lipase. A yeast expression plasmid containing the phosphoglycerate kinase promoter and terminator sequences together with the human gastric lipase gene was constructed. Yeast transformed with this vector synthesised the lipolytically active enzyme.  相似文献   
944.
The emerald ash borer (EAB) (Agrilus planipennis Fairmaire) (Coleoptera; Buprestidae), is an invasive wood-boring beetle native to northeast Asia. This species was first detected in Michigan USA in 2002, and is a significant threat to native and ornamental ash tree species (Fraxinus spp.) throughout North America. We characterized seven polymorphic microsatellite markers for EAB and used these to investigate EAB population structure in the early invasive populations within North America and in comparison with Asia. We found 2–9 alleles per microsatellite locus, no evidence of linkage disequilibrium, and no association with known coding sequences, suggesting that these markers are suitable for population genetic analysis. Microsatellite population genetic structure was examined in 48 EAB populations sampled between 2003 and 2008 from five regions, three in the introduced range, Michigan (US) and Ontario and Quebec (Canada) and two Asian regions, China and South Korea, where EAB is native. We found significant genetic variation geographically but not temporally in EAB populations. Bayesian clustering analyses of individual microsatellite genotypes showed strong clustering among multiple North American populations and populations in both China and South Korea. Finally, allelic richness and expected heterozygosity were higher in the native range of EAB, but there was no difference in observed heterozygosity, suggesting a significant loss of alleles upon introduction but no significant change in the distribution of alleles within and among individuals.  相似文献   
945.
Parasites profoundly influence the lives of their hosts, yet the dynamics of host–parasite interactions are poorly understood – especially in reptiles. We examined the ecological correlates of parasitism by ixodid ticks in an assemblage of 10 snake species in tropical Australia. In total, we recorded 3803 ticks on 1841 individual snakes of six species (no ticks were found on the other species). Molecular analyses confirmed the tropical reptile tick (Amblyomma fimbriatum: Ixodidae) to be the most common snake tick at our study site, with inter‐ and intraspecific variation in tick prevalence and intensity. Tick attachment sites were random on most snake species, but both male and female ticks congregated on the heads of the colubrid snake Boiga irregularis and the python Simalia amethistina. In these same species, tick loads were higher on snakes captured in woodland than in rainforest. Females of two python species (Aspidites melanocephalus and S. amethistina) had higher tick loads than did males. In B. irregularis, individuals captured in the dry season had higher tick loads than those captured in the wet season. In most parasitized snake species, larger individuals had greater tick loads. Data from snake recaptures confirmed individual tick burdens frequently varied, with little correlation between tick loads on the same snake at successive captures (except for B. irregularis). Finally, tick intensity was not correlated with (and thus, presumably did not influence) the body condition of any snake species in our study. Use of specific types of refuge sites may strongly influence tick loads on snakes in this system.  相似文献   
946.
BackgroundThere is increasing interest in reconstruction of diabetes-associated Charcot foot arthropathy with the goal of improving quality of life.MethodsTwenty-four patients who completed the Short Musculoskeletal Function Assessment (SMFA) at baseline and one year following Charcot foot reconstruction were contacted and asked to complete the survey at five years following surgery.ResultsFourteen of the 24 patients completed the SMFA preoperatively, one year following surgery and five years postoperatively. Two patients underwent below knee amputation in the interim. Improvement was noted in all domains measured by the SMFA, with a statistically significant improvement in difficulty with daily activities at five years.ConclusionCorrection of non-plantigrade Charcot foot arthropathy results in clinically meaningful improvement in health-related quality of life at both one and five years postoperatively, including independence with daily activities. The improvement is maintained when reevaluated at five years. This supports the modern paradigm shift towards reconstruction of this deformity. Level of Evidence: III  相似文献   
947.
The Lombard effect describes the automatic and involuntary increase in vocal intensity that speakers exhibit in a noisy environment. Previous studies of the Lombard effect have typically focused on the relationship between speaking and hearing. Automatic and involuntary increases in motor output have also been noted in studies of finger force production, an effect attributed to mechanisms of sensory attenuation. The present study tested the hypothesis that sensory attenuation mechanisms also underlie expression of the Lombard effect. Participants vocalized phonemes in time with a metronome, while auditory and visual feedback of their performance were manipulated or removed during the course of the trial. We demonstrate that providing a visual reference to calibrate somatosensory-based judgments of current vocal intensity resulted in reduced expression of the Lombard effect. Our results suggest that sensory attenuation effects typically seen in fingertip force production play an important role in the control of speech volume.  相似文献   
948.
Murine mammary carcinoma cells (line 67) were grown in unfed cultures for up to 9 days. In cultures (day 2-3) in which cells were proliferatively active and in day 3-5 (transition) cells, a large fraction of nuclear DNA was retained on polycarbonate filters when assayed by the alkaline filter elution technique. In contrast, the fraction of DNA retained on filters was significantly reduced for nonproliferating (Q, quiescent) cells from unfed 7-9 day cultures. The increase in endogenous DNA breaks followed both the decrease in proliferative state and clonogenicity in these cells. When day 7 Q cells were refed these endogenous DNA breaks were removed with a half-time of about 2.5 h. When the cells were exposed to X-irradiation and the integrity of their nuclear DNA measured by the alkaline filter elution assay, as much as a 2-fold greater frequency of radiation-induced DNA breaks was produced in Q versus P cells. DNA breaks were also removed from irradiated Q cells at a rate which was 0.23 that observed in P cells. We suggest that the depressed capacity for DNA damage removal in Q cells is responsible for their greater radiosensitivity, and the impaired DNA damage repair is probably due to a reduced level of energy sources in these unfed Q cell cultures.  相似文献   
949.
Genome-wide association studies (GWAS) have transformed our understanding of the genetics of complex traits such as autoimmune diseases, but how risk variants contribute to pathogenesis remains largely unknown. Identifying genetic variants that affect gene expression (expression quantitative trait loci, or eQTLs) is crucial to addressing this. eQTLs vary between tissues and following in vitro cellular activation, but have not been examined in the context of human inflammatory diseases. We performed eQTL mapping in five primary immune cell types from patients with active inflammatory bowel disease (n = 91), anti-neutrophil cytoplasmic antibody-associated vasculitis (n = 46) and healthy controls (n = 43), revealing eQTLs present only in the context of active inflammatory disease. Moreover, we show that following treatment a proportion of these eQTLs disappear. Through joint analysis of expression data from multiple cell types, we reveal that previous estimates of eQTL immune cell-type specificity are likely to have been exaggerated. Finally, by analysing gene expression data from multiple cell types, we find eQTLs not previously identified by database mining at 34 inflammatory bowel disease-associated loci. In summary, this parallel eQTL analysis in multiple leucocyte subsets from patients with active disease provides new insights into the genetic basis of immune-mediated diseases.  相似文献   
950.
A novel microperifusion system with capabilities for continuous, real-time, potentiometric monitoring of extracellular hydrogen ion concentration has been used to define the response of HeLa cells to abrupt changes in extracellular energy sources or introduction of an inhibitor of glycolysis. Glycolytic inhibition, induced by removal of glucose or introduction of iodoacetate, each led to a rapid, continuous decrease in acid release. The response to iodoacetate took longer than removal of glucose, perhaps due to the time required for binding and activation. Once inhibition began, however, the rate of change was greater than following glucose removal. Conversely, recovery time following iodoacetate inhibition was much slower than with glucose removal. Unlike the response to short-term glucose depletion, a second pulse of iodoacetate resulted in a faster response followed by an even longer recovery time. The response to switching between glucose and glutamine began almost without evident delay. The response patterns revealed that HeLa cells prefer glutamine to glucose, but, in the presence of both energy sources, some glucose continues to be used. In summary, these results indicate that continuous, real-time monitoring of the kinetics of hydrogen-ion release can be used to gain new insights into the dynamics of cellular response to perturbations of extracellular energy sources. © 1994 Wiley-Liss, Inc.  相似文献   
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