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Mycopathologia - Se estudiaron los resultados comparativos de las reacciones intradérmicas a la Tuberculina, Histoplasmina y Coccidioidina, practicadas simultáneamente a 644 enfermos...  相似文献   
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Summary Our working hypothesis is that the Q-darker human chromosome segments have higher gene densities than the bright regions. Especially prominent in this respect are six hot spots, the short Q-dark regions in 3p, 6p, 11q, 12q, 17q, and 19 (p or q), which have been chosen because their density of mitotic chiasmata is above 5. Chromosomes with gene-rich segments would act as trisomy lethals in very early embryos, whose spontaneous abortions would not be recognized. Containing active genes, the regions would be looped out in interphase and thus be more easily available for mitotic pairing and crossing-over.To test this hypothesis, correlations and partial correlations of the following parameters have been determined: the density of mitotic chiasmata, the number and density of localized genes, the incidence of trisomic abortions, the length of chromosomes, and their Q-brightness. Overall, the correlations and partial correlations agree with, but do not prove, the working hypothesis. Far stronger evidence for our hypothesis comes from the highly significant negative effect of hot spots on trisomic abortions which would act as a kind of trisomy lethal. The gene numbers on the hot-spot chromosomes as compared with the controls, on the other hand, are in the right direction, but the difference is not significant.This is paper No. 2161 from the Genetics Laboratory, University of Wisconsin. It was supported by National Institutes of Health (Washington) grants GM 22881, GM 15422-09, and, to Dr. Hans Ris, GM 04738; by grant IN-35P from the American Cancer Society, and by the U. W. Graduate Research Committee (Grant 101-4403). The photography was done by Mr. Walter Kugler, Jr.  相似文献   
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Isolated hamster intestinal epithelial cells can be separated by velocity sedimentationion on 2–10% Ficoll gradients into three subpopulations of cells which differ in morphology, biochemistry, physiology, and membrane components. These subpopulations are not pure but are enriched in a single cell type to the extent that differences in cell function can be observed. The proliferative crypt cells are separated from the digestive-absorptive villus cells. A third subpopulation with a distinctive morphology is also obtained. Quantitation of DNA recoveries from the gradients indicates that this population constitutes approximately one-third of the epithelial cell population. These carrot-shaped cells are found adjacent to the digestive-absorptive columnar epithelial cells on the villus. The two types of villus cells differ in glycolipid or glycoprotein components of the brush border as shown by lectin binding experiments with the isolated cells. The gradient data also suggest that only one-third of the intestinal epithelial cell population is responsible for most monosaccharide absorption in hamster small intestine.  相似文献   
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Reading disabilities (RD) are the most common neurocognitive disorder, affecting 5% to 17% of children in North America. These children often have comorbid neurodevelopmental/psychiatric disorders, such as attention deficit/hyperactivity disorder (ADHD). The genetics of RD and their overlap with other disorders is incompletely understood. To contribute to this, we performed a genome‐wide association study (GWAS) for word reading. Then, using summary statistics from neurodevelopmental/psychiatric disorders, we computed polygenic risk scores (PRS) and used them to predict reading ability in our samples. This enabled us to test the shared aetiology between RD and other disorders. The GWAS consisted of 5.3 million single nucleotide polymorphisms (SNPs) and two samples; a family‐based sample recruited for reading difficulties in Toronto (n = 624) and a population‐based sample recruited in Philadelphia [Philadelphia Neurodevelopmental Cohort (PNC)] (n = 4430). The Toronto sample SNP‐based analysis identified suggestive SNPs (P ~ 5 × 10?7) in the ARHGAP23 gene, which is implicated in neuronal migration/axon pathfinding. The PNC gene‐based analysis identified significant associations (P < 2.72 × 10?6) for LINC00935 and CCNT1, located in the region of the KANSL2/CCNT1/LINC00935/SNORA2B/SNORA34/MIR4701/ADCY6 genes on chromosome 12q, with near significant SNP‐based analysis. PRS identified significant overlap between word reading and intelligence (R2 = 0.18, P = 7.25 × 10?181), word reading and educational attainment (R2 = 0.07, P = 4.91 × 10?48) and word reading and ADHD (R2 = 0.02, P = 8.70 × 10?6; threshold for significance = 7.14 × 10?3). Overlap was also found between RD and autism spectrum disorder (ASD) as top‐ranked genes were previously implicated in autism by rare and copy number variant analyses. These findings support shared risk between word reading, cognitive measures, educational outcomes and neurodevelopmental disorders, including ASD.  相似文献   
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The ER‐bound kinase/endoribonuclease (RNase), inositol‐requiring enzyme‐1 (IRE1), regulates the phylogenetically most conserved arm of the unfolded protein response (UPR). However, the complex biology and pathology regulated by mammalian IRE1 cannot be fully explained by IRE1’s one known, specific RNA target, X box‐binding protein‐1 (XBP1) or the RNA substrates of IRE1‐dependent RNA degradation (RIDD) activity. Investigating other specific substrates of IRE1 kinase and RNase activities may illuminate how it performs these diverse functions in mammalian cells. We report that macrophage IRE1 plays an unprecedented role in regulating phosphatidylinositide‐derived signaling lipid metabolites and has profound impact on the downstream signaling mediated by the mammalian target of rapamycin (mTOR). This cross‐talk between UPR and mTOR pathways occurs through the unconventional maturation of microRNA (miR) 2137 by IRE1’s RNase activity. Furthermore, phosphatidylinositol (3,4,5) phosphate (PI(3,4,5)P3) 5‐phosphatase‐2 (INPPL1) is a direct target of miR‐2137, which controls PI(3,4,5)P3 levels in macrophages. The modulation of cellular PI(3,4,5)P3/PIP2 ratio and anabolic mTOR signaling by the IRE1‐induced miR‐2137 demonstrates how the ER can provide a critical input into cell growth decisions.  相似文献   
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The role of herbivorous fish in threatening marine forests of temperate seas has been generally overlooked. Only recently, the scientific community has highlighted that high fish herbivory can lead to regime shifts from canopy‐forming algae to less complex turf communities. Here, we present an innovative herbivorous fish deterrent device (DeFish), which can be used for conservation and restoration of marine forests. Compared to most traditional fish exclusion systems, such as cages, the DeFish system does not need regular cleaning and maintenance, making it more cost‐efficient. Resistance of DeFish was tested by installing prototypes at different depths in the French Riviera and in Montenegro: more than 60% of the devices endured several years without maintenance, even if most of them were slightly damaged in the exposed site in Montenegro. The efficacy of DeFish in limiting fish herbivory was tested by an exclusion experiment on Cystoseira amentacea in the French Riviera. In a few months, the number of fish bite marks on the seaweed was decreased, causing a consequent increase in algal length. The device here presented has been conceived for Mediterranean canopy‐forming algae, but the same concept can be applied to other species vulnerable to fish herbivory, such as kelps or seagrasses. In particular, the DeFish design could be improved using more robust and biodegradable materials. Innovative engineering systems, such as DeFish, are expected to become useful tools in the conservation and restoration of marine forests, to complement other practices including active reforestation, herbivore regulation, and regular monitoring of their status.  相似文献   
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Physiology and Molecular Biology of Plants - Transgenic tobacco (N. tabacum cv. Xanthi nc) expressing Capsicum chinense&nbsp;CchGLP gene that encodes an Mn-SOD, constitutively produces hydrogen...  相似文献   
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