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991.
In this paper we report on the process of translating five mental health outcome measures into Spanish and adapting them to Latino culture. The instruments considered are the World Health Organization-Disability Assessment Scale, the Burden Assessment Scale, the Family Burden Scale, Lehman's Quality of Life Interview and the Continuity of Care in Mental Health Services Interview. A systematic process of translation and adaptation of the instruments was followed with the goal of achieving cultural equivalence between the English and Spanish versions of the instruments in five dimensions: semantic, content, technical, construct, and criterion equivalence. In this paper we present data about the semantic, content, and technical equivalence. Various steps were taken to achieve equivalence in these dimensions, including the use of a bilingual committee, a multi-national bilingual committee, back-translation, and focus groups with mental health patients and their relatives.  相似文献   
992.
The X-linked agammaglobulinaemia (XLA) gene locus has previously been mapped to Xq22. Genetic linkage analysis has shown tight linkage between the disease and the DXS178 locus and that DXS3 and DXS94 are the closest proximal and distal flanking markers, respectively, separated by a genetic distance of 10–12 cM. We attempted to construct a physical map of Xq22 using pulsed field gel electrophoresis (PFGE) and rare-cutting restriction enzymes in order to obtain a finite physical value for the distance between DXS3 and DXS94. However, these attempts were hampered by the large number of rare-cutting restriction enzyme sites around the DXS178 locus, indicative of the presence of CpG rich regions of DNA. We were able to construct a physical map of the sites close to DXS178 that suggests the presence of at least three, and perhaps as many as five, CpG islands. These are arranged on either side of DXS178, extending over about 550kb of genomic DNA. Each of these regions must be considered as being associated with a potential candidate gene sequence for the XLA gene and we have initiated a chromosome walk from DXS178 to the nearest of these islands.  相似文献   
993.
Homologous recombination between dispersed repeated sequences is important in shaping eukaryotic genome structure, and such ectopic interactions are affected by repeat size and sequence identity. A transformation-based, gap-repair assay was used to examine the effect of 2% sequence divergence on the efficiency of mitotic double-strand break repair templated by chromosomal sequences in yeast. Because the repaired plasmid could either remain autonomous or integrate into the genome, the effect of sequence divergence on the crossover-noncrossover (CO-NCO) outcome was also examined. Finally, proteins important for regulating the CO-NCO outcome and for enforcing identity requirements during recombination were examined by transforming appropriate mutant strains. Results demonstrate that the basic CO-NCO outcome is regulated by the Rad1-Rad10 endonuclease and the Sgs1 and Srs2 helicases, that sequence divergence impedes CO to a much greater extent than NCO events, that an intact mismatch repair system is required for the discriminating identical and nonidentical repair templates, and that the Sgs1 and Srs2 helicases play additional, antirecombination roles when the interacting sequences are not identical.  相似文献   
994.
An essential component of microtubules, alpha-tubulin is also a multigene family in many species. An orthology-based nomenclature for this gene family has previously been difficult to assign due to incomplete genome builds and the high degree of sequence similarity between members of this family. Using the current genome builds, sequence analysis of human, mouse, and rat alpha-tubulin genes has enabled an updated nomenclature to be generated. This revised nomenclature provides a unified language for the discussion of these genes in mammalian species; it has been approved by the gene nomenclature committees of the three species and is supported by researchers in the field.  相似文献   
995.
Four new 28-nor-oleanane-type triterpene oligoglycosides, camellenodiol 3-O-β-D-galactopyranosyl(1→2)[β-D-xylopyranosyl(1→2)-β-D-galactopyranosyl(1→3)]-β-D-glucuronopyranoside (2), camellenodiol 3-O-4'-O-acetyl-β-D-galactopyranosyl(1→2)[β-D-xylopyranosyl(1→2)-β-D-galactopyranosyl(1→3)]-β-D-glucuronopyranoside (4), camellenodiol 3-O-(β-D-galactopyranosyl(1→2)[β-D-xylopyranosyl(1→2)-β-D-galactopyranosyl(1→3)]-6'-methoxy-β-D- glucuronopyranoside (5), and maragenin II 3-O-(β-D-galactopyranosyl(1→2)[β-D-xylopyranosyl(1→2)-β-D-galactopyranosyl(1→3)]-6'-methoxy-β-D-glucuronopyranoside (6), along with two known compounds, (1 and 3), were isolated from the stem bark of Camellia japonica. Their chemical structures were established mainly by 2D NMR techniques and mass spectrometry. The isolated compounds showed inhibitory effects on NO production in RAW264.7 macrophages.  相似文献   
996.
Low bone mineral density (BMD) has been determined as an independent factor of osteoporosis. The purpose of this study was to assess physical activity's effect on BMD in college-aged women. Bone density measurements were obtained. A survey was administered to assess past and recent physical activity levels. Logistic regression revealed high school sports participation and lean tissue were significant predictors of femoral BMD, whereas present physical activity and lean tissue were significant predictors of spinal BMD. Women in the present study who did not participate in high school sports were 7 times more likely to have low BMD than were those who participated. This study revealed a protective effect of past and present physical activity on BMD in college-aged women. Children and young adults should be encouraged to participate in physical activity because it helps reduce their risk factors for osteoporosis later in life.  相似文献   
997.
It was not known if Cannabichromene (CBC), which is a major constituent of drug types of Cannabis, has anti-inflammatory properties as do other cannabinoids. CBC was tested in vivo using the rat paw edema test and in vitro using the erythrocyte membrane stabilization assay. CBC was as effective as phenylbutazone (PBZ) at equivalent doses. Since CBC is less toxic than PBZ, larger doses may be given to produce a greater therapeutic effect.  相似文献   
998.
H(2)O(2) is a reactive oxygen species that has drawn much interest because of its role as a second messenger in receptor-mediated signaling. Mammalian 2-Cys peroxiredoxins have been shown to eliminate efficiently the H(2)O(2) generated in response to receptor stimulation. 2-Cys peroxiredoxins are members of a novel peroxidase family that catalyze the H(2)O(2) reduction reaction in the presence of thioredoxin, thioredoxin reductase and NADPH. Several lines of evidence suggest that 2-Cys peroxiredoxins have dual roles as regulators of the H(2)O(2) signal and as defenders of oxidative stress. In particular, 2-Cys peroxiredoxin appears to provide selective, specific and localized control of receptor-mediated signal transduction. Thus, the therapeutic potential of 2-Cys peroxiredoxins is clear for diseases, such as cancer and cardiovascular diseases, that involve reactive oxygen species.  相似文献   
999.
Cellular metabolism of dopamine (DA) generates H2O2, which is further reduced to hydroxyl radicals in the presence of iron. Cellular damage inflicted by DA-derived hydroxyl radicals is thought to contribute to Parkinson's disease. We have previously developed procedures for detecting proteins that contain H2O2-sensitive cysteine (or selenocysteine) residues. Using these procedures, we identified ERP72 and ERP60, two members of the protein disulfide isomerase family, creatine kinase, glyceraldehyde-3-phosphate dehydrogenase, phospholipase C-gamma1, and thioredoxin reductase as the targets of DA-derived H2O2. Experiments with purified enzymes identified the essential Cys residues of creatine kinase and glyceraldehyde-3-phosphate dehydrogenase, that are specifically oxidized by H2O2. Although the identified proteins represent only a fraction of the targets of DA-derived H2O2, functional impairment of these proteins has previously been associated with cell death. The oxidation of proteins that contain reactive Cys residues by DA-derived H2O2 is therefore proposed both to be largely responsible for DA-induced apoptosis in neuronal cells and to play an important role in the pathogenesis of Parkinson's disease.  相似文献   
1000.
Details of the general DNA sequence organization in the dinoflagellate Crypthecodinium cohnii have been obtained by using hydroxylapatite binding experiments, S1 nuclease digestion .and electron microscopy of reassociated DNA. It has been found that roughly half of the genome is made up of unique sequences interspersed with repeated sequence elements with a period of approximately 600 nucleotides. This class represents roughly 95% of the total number of interspersed unique elements in the genome. The remaining 5% are uninterrupted by repeated sequences for at least 4000 nucleotide pairs. The interspersed repeated elements are narrowly distributed in length with 80% under 300 nucleotide pairs in length. About half of the repeated DNA (20-30% of the genome) is not interspersed among unique sequences. The close spacing of the short repeats interspersed throughout much of the genome is consistent with the occurrence of the huge network structures observed in the electron microscope for low Cot reassociation of moderately long fragments. An unusual class of heteroduplexes was detected in the electron microscope which is believed to derive from the reassociation of repeated sequences from different families which are frequently found adjacent to one another in different locations in the genome. The occurrence of this novel arrangement of repeated sequences may reflect the unusual organization of the dinoflagellate nucleus. However, in most respects the sequence arrangement in this unicellular alga is very typical of higher plants and animals.  相似文献   
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