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31.
Cryptomeria japonica pollinosis is one of the most serious allergic diseases in Japan; this is a social problem because C. japonica is the most important Japanese forestry species. In order to reduce the amount of pollen dispersed, breeding programs using trees with male-sterile genes have been implemented. High-density linkage maps with stable ordering of markers facilitate the localization of male-sterile genes and the construction of partial linkage maps around them in order to develop markers for use in marker-assisted selection. In this study, a high-density linkage map for C. japonica with 2560 markers was constructed. The observed map length was 1266.2 cM and the mean distance between adjacent markers was 0.49 cM. Using information from this high-density map, we newly located two male-sterile genes (ms3 and ms4) on the first and fourth linkage groups, respectively, and constructed partial linkage maps around these loci. We also constructed new partial linkage maps around the ms1 and ms2 loci using additional SNP markers. The closest markers to the ms1, ms2, ms3, and ms4 male-sterile loci were estSNP04188 (1.8 cM), estSNP00695 (7.0 cM), gSNP05415 (3.1 cM), and estSNP01408 (7.0 cM) respectively. These results allowed us to develop SNP markers tightly linked to the male sterile genes for use in MAS; this will accelerate the future isolation of these genes by map-based cloning approaches.  相似文献   
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BackgroundAlthough several computer-aided computed tomography (CT) analysis methods have been reported to objectively assess the disease severity and progression of idiopathic pulmonary fibrosis (IPF), it is unclear which method is most practical. A universal severity classification system has not yet been adopted for IPF.ObjectiveThe purpose of this study was to test the correlation between quantitative-CT indices and lung physiology variables and to determine the ability of such indices to predict disease severity in IPF.MethodsA total of 27 IPF patients showing radiological UIP pattern on high-resolution (HR) CT were retrospectively enrolled. Staging of IPF was performed according to two classification systems: the Japanese and GAP (gender, age, and physiology) staging systems. CT images were assessed using a commercially available CT imaging analysis workstation, and the whole-lung mean CT value (MCT), the normally attenuated lung volume as defined from −950 HU to −701 Hounsfield unit (NL), the volume of the whole lung (WL), and the percentage of NL to WL (NL%), were calculated.ResultsCT indices (MCT, WL, and NL) closely correlated with lung physiology variables. Among them, NL strongly correlated with forced vital capacity (FVC) (r = 0.92, P <0.0001). NL% showed a large area under the receiver operating characteristic curve for detecting patients in the moderate or advanced stages of IPF. Multivariable logistic regression analyses showed that NL% is significantly more useful than the percentages of predicted FVC and predicted diffusing capacity of the lungs for carbon monoxide (Japanese stage II/III/IV [odds ratio, 0.73; 95% confidence intervals (CI), 0.48 to 0.92; P < 0.01]; III/IV [odds ratio. 0.80; 95% CI 0.59 to 0.96; P < 0.01]; GAP stage II/III [odds ratio, 0.79; 95% CI, 0.56 to 0.97; P < 0.05]).ConclusionThe measurement of NL% by threshold-based volumetric CT analysis may help improve IPF staging.  相似文献   
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Prey evolve antipredator strategies against multiple enemies in nature. We examined how a prey species adopts different predation avoidance tactics against pursuit or sit‐and‐wait predators. As prey, we used three strains of Tribolium beetles artificially selected for short (short strain) or long (long strain) duration of death feigning, and a stock culture (base population). Death feigning is known to be effective for evading a jumping spider in the case of the long strains, while the present study showed that the long‐strain beetles used freezing against a sit‐and‐wait type predator, Amphibolus venator, in this study. The short‐ strain beetles were more easily oriented toward predators. The time to predation was also shorter in the short strains compared to the long strains. The results showed that, as prey, the short strains displayed the same behavior, escaping, against both types of predators. Traditionally, death feigning has been thought to be the last resort in a series of antipredator avoidance behaviors. However, our results showed that freezing and death feigning were not parts of a series of behaviors, but independent strategies against different predators, at least for long‐strain beetles. We also examined the relationship between a predator''s starvation level and its predatory behavior. In addition, the orientation behavior toward and predation rate on the prey were observed to determine how often the predatory insect attacked the beetles.  相似文献   
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We compared the relaxant effect of original pituitary adenylate cyclase-activating peptide (PACAP)1-27 with that of a newly developed, synthetic PACAP1-27 analogue, [Arg15,20,21 Leu17]-PACAP-Gly-Lys-Arg-NH2, in human bronchi in vitro (n=4-5 in each group). Using precontraction by carbachol (0.1 microM), cumulative administration of PACAP1-27 and salbutamol caused concentration-dependent smooth muscle relaxation with similar potencies and maximum relaxant effects. Non-cumulative administration of the PACAP1-27 analogue and the original PACAP1-27 caused concentration-dependent relaxation with a similar maximum relaxant effect and potency as well. However, the onset and offset of action was markedly slower for the PACAP1-27 analogue than for the original PACAP1-27 (>90% versus <10% of peak relaxation remaining 5 h after administration). Peptidase inhibition by captopril (10 microM) and phosphoramidon (1 microM) significantly increased the maximum relaxant effect and duration of action of PACAP1-27 but not of the PACAP1-27 analogue, during the 3 h of observation in the human bronchi. We conclude that [Arg15,20,21 Leu17]-PACAP-Gly-Lys-Arg-NH2 produces significant concentration-dependent and sustained bronchial smooth muscle relaxation in vitro. The sustained relaxant effect is due, at least in part, to the synthetic PACAP1-27 analogue being less susceptible to cleavage by peptidases than the original peptide PACAP1-27.  相似文献   
39.
Various types of stress, such as disruption of calcium homeostasis, inhibition of protein glycosylation and reduction of disulfide bonds, result in accumulation of misfolded proteins in the endoplasmic reticulum (ER). The initial cellular response involves removal of such proteins by the ER, but excessive and/or long-term stress results in apoptosis. In this study, we used a randomized ribozyme library and ER stress-mediated apoptosis (tunicamycin-induced apoptosis) in SK-N-SH human neuroblastoma cells as a selective phenotype to identify factors involved in this process. We identified a double-stranded RNA-dependent protein kinase (PKR) as one of the participants in this process. The level of nuclear PKR was elevated, but the level of cytoplasmic PKR barely changed in tunicamycin-treated SK-N-SH cells. Furthermore, tunicamycin also raised levels of phosphorylated PKR in the nucleus. We also detected the accumulation of phosphorylated PKR in the nuclei of autopsied brain tissues in Alzheimer's disease. Thus, PKR might play a role in ER stress-induced apoptosis and in Alzheimer's disease.  相似文献   
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We determined the complete nucleotide sequences of the mitochondrial genomes for the three currently recognized species of ocean sunfish: Mola mola, Masturus lanceolatus, and Ranzania laevis (Tetraodontiformes: Molidae). Each genome contained the 37 genes as found in teleosts, with the typical gene order in teleosts. Bayesian, maximum-likelihood, and maximum-parsimony analyses were conducted with the data set comprising concatenated nucleotide sequences from 36 genes (excluding the ND6 gene) of three molids and four outgroups (three tetraodontiforms plus a caproid). The resultant trees supported monophyly of the Molidae and its intrarelationships ((Mola, Masturus), Ranzania), which were congruent with previous morphology-based hypotheses.  相似文献   
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