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991.
A novel compound for use in magnetic resonance (MR) imaging was created by covalently bonding multiple 19F atom tags to L-DOPA. Tagging L-DOPA permits bypassing the rate-limiting factor in the biosynthesis of dopamine (DA), the conversion of tyrosine into L-DOPA. The next step in the biosynthetic pathway, the removal of the carboxyl group on the molecule by the enzyme L-aromatic acid decarboxylase (AADC), happens rapidly after L-DOPA is taken up into neurons. In order to be useful as a tool in MR imaging, the novel compound and/ or its perfluoro-tagged metabolites must accumulate in vesicles in dopaminergic neurons. We administered L-DOPA with a nine 19F atom tag (250 mg/kg) to mice pups, waited 1.5 or 3 hr, and used high pressure liquid chromatography (HPLC) to examine neural tissue samples for tagged L-DOPA and tagged DA. The isomer of L-DOPA with the tag bonded at the 5 position yielded the highest conversion to tagged DA at 1.5 hr after an i.p. injection. This study provides the first direct evidence that L-DOPA, tagged with nine fluorine atoms, is taken up into mammalian brain dopaminergic neurons where it is converted to perfluro-tagged DA. The use of these tagged compounds may make it feasible to investigate the uptake and conversion of important neurotransmitter in vivo with fluorine imaging.  相似文献   
992.
Human immunodeficiency virus type 2 (HIV-2) is the result of cross-species transmission of simian immunodeficiency virus (SIV) from sooty mangabey monkeys to humans. Primer pairs (intHIV-2/SIV) based on a region of integrase that has considerable homology across HIV-2 and SIV lineages were designed to develop a broadly cross-reactive molecular assay to detect lentivirus infection in primates. The intHIV-2/SIV primers detect HIV-2 and simian viruses SIVcpz, SIVsmm, SIVsyk, SIVagm, and SIVmnd. The primers are also capable of amplifying some HIV-1 strains. Additionally, sequences from the integrase amplicons were of sufficient genetic diversity to permit not only phylogenetic clustering of all simian viruses to their respective lineages but also HIV type and group classification. Thus, the primers described here provide a method to detect primate lentiviruses from diverse species of nonhuman primates, as well as from persons infected with HIV-1 and HIV-2.  相似文献   
993.
OBJECTIVE: Many teen parents and their babies are at a significant disadvantage because of poverty and inadequate parenting skills. We undertook a study aimed at increasing parenting skills and improving attitudes of teen mothers through a structured psychoeducational group model based on the Nurturing Curriculum. METHODS: All adolescent mothers in the Young Parents' Program were offered enrollment in a 12-week group parenting curriculum (intervention group) and were compared with those who declined the intervention but agreed to participate as comparison subjects (comparison group). This study had an intervention-comparison group design with pretest and posttest measures, including the Adult-Adolescent Parenting Inventory (AAPI), the Maternal Self-Report Inventory (MSRI), and the Parenting Daily Hassles Scale (Hassles Scale). RESULTS: There were 91 young mothers in the intervention group compared with 54 in the comparison group. While controlling for mother's age, baby's age, and race, the repeated-measures analyses showed that mothers who participated in the intervention group or attended more group sessions experienced improvements in their mothering role (MSRI) (trend), perception of childbearing experience (MSRI), appropriate developmental expectations of their child (AAPI), empathy for the baby (AAPI), and a reduction in the frequency of hassles in child and family events (Hassles Scale). CONCLUSION: The intervention group showed improvement in parenting skills and life hassles after participation in the intervention curriculum. More interventions are needed to confirm the positive effect of the group-based interventions on parenting and life skills of young mothers that may improve the social, emotional, and cognitive outcomes for the children born to teen parents.  相似文献   
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995.
Two different axonal transport tracers were used in single animals to test the hypothesis that the expansive intermediate gray layer of the cat superior colliculus (stratum griseum intermediale, SGI) is composed of sensorimotor domains. The results show that two sensory pathways, the trigeminotectal and the corticotectal arising from the fourth somatosensory area, commingle in patches across the middle tier of the SGI. Furthermore, the data reveal that tectospinal cells are distributed within these patches. Taken together, these results show a commingling of functionally related afferents and a consistent spatial relationship between these afferents and tectospinal neurons. These relationships indicate that the SGI consists of domains that can be distinguished by their unique combinations of afferent and efferent connections. The ultrastructural characteristics and synaptic relationships of these somatosensory afferent pathways suggest that they have distinct roles within the sensorimotor domain of the SGI. The trigeminotectal terminals are relatively small, contain round vesicles and make asymmetrical synapses on small, presumably distal, dendrites. We submit that these trigeminal terminals bestow the basic receptive field properties upon SGI neurons. In contrast, the somatosensory corticotectal terminals are relatively large, contain round vesicles, make asymmetrical synapses, participate in triads, and are presynaptic to proximal dendrites. We suggest that these cortical terminals bestow integrative abilities on SGI neurons. J. Comp. Neurol. 388:313–326, 1997. © 1997 Wiley-Liss, Inc.  相似文献   
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998.
This study tested the hypothesis that depression, anxiety, and bizarre thought content, as measured by MMPI-2 scales, would show a negative relationship with performance on widely used measures of executive functioning. Subjects were 70 male psychiatric patients who were ostensibly free of any neurologic disease or history of substance abuse. Correlational analyses were performed between age and education-corrected scores on the Controlled Oral Word Association Test (FAS), Design Fluency, and WISC-R Mazes, and scores on MMPI-2 scales D, PT , Anxiety, Fears, Obsessional Thinking, Depression, and Bizarre Mentation. The findings suggest that fluency and maze performance is (1) largely independent of measures of depression (D, DEP) and bizarre mentation (BIZ); (2) mildly associated with a measure of generalized anxiety (ANX); and (3) strongly related to an MMPI-2 measure of fearfulness (FRS).  相似文献   
999.
Objective. Myositis-specific autoantibodies (MSA) define relatively homogenous clinical and immunogenetic patient groups in adults with idiopathic inflammatory myopathies (IIM). This study explores the usefulness of MSA in defining groups of children with myositis. Methods. Sera from 77 children with myositis and other connective tissue diseases were tested for MSA by immunoprecipitation and immunodiffusion. Clinical data were collected and analyzed. Results. The MSA anti-PL-12 (alanyl-transfer RNA synthetase), anti-Jo-1 (histidyl-tRNA synthetase), anti-signal recognition particle, and anti-Mi-2 were each identified in the sera of 12 children with IIM. In these patients, the clinical manifestations, disease courses, and responses to therapy closely resembled those in adults with the same autoantibodies. Conclusion. These observations suggest that the clinical syndromes defined by particular MSA are similar in children and adults with IIM. By defining similar clinical syndromes in children who have MSA, this study provides a basis for future studies of MSA in the idiopathic inflammatory myopathies of childhood, which may be useful in predicting the clinical courses of a subset of these patients and improving their therapy.  相似文献   
1000.
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