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51.
Alcohol dependence is a leading cause of morbidity and mortality in Native Americans, yet biological factors underlying the disorder in this ethnic group remain elusive. This study's aims were to map susceptibility loci for DSM-III-R alcohol dependence and two narrower alcohol-related phenotypes in Mission Indian families. Each participant gave a blood sample and completed an interview using the Semi-Structured Assessment for the Genetics of Alcoholism (SSAGA) that was used to make alcohol dependence diagnoses and the narrower phenotypes of withdrawal, and drinking severity. Genotypes were determined for a panel 791 microsatellite polymorphisms. Analyses of multipoint variance component LOD scores for the dichotomous DSM-III-R phenotype revealed no peak LOD scores that exceeded 2.0 at any chromosome location. Two chromosomes, 4 and 12, had peak LOD scores that exceeded 2 for the alcohol use severity phenotype and three chromosomes 6, 15, 16 were found to have peaks with LOD scores that exceeded 2 for the withdrawal phenotype. Evidence for linkage to chromosomes 4 and 15, and 16 have been reported previously for alcohol related phenotypes whereas no evidence has as yet been reported for chromosomes 6 and 12. Combined linkage and association analysis suggest that alcohol dehydrogenase 1B gene polymorphisms are partially responsible for the linkage result on chromosome 4 in this population. These results corroborate the importance of several chromosomal regions highlighted in prior segregation studies in alcoholism and further identify new regions of the genome that may be unique to either the restricted phenotypes evaluated or this population of Mission Indians.  相似文献   
52.
Journal of Occupational Rehabilitation - Purpose Both personal and work-related factors affect return to work (RTW) after total knee arthroplasty (TKA) and total hip arthroplasty (THA). Little is...  相似文献   
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Advances in Health Sciences Education - When physicians do not estimate their diagnostic accuracy correctly, i.e. show inaccurate diagnostic calibration, diagnostic errors or overtesting can occur....  相似文献   
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The net impact of cytomegalovirus (CMV) DNAemia on overall mortality (OM) and nonrelapse mortality (NRM) following allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains a matter of debate. This was a retrospective, multicenter, noninterventional study finally including 749 patients. CMV DNA monitoring was conducted by real-time polymerase chain reaction (PCR) assays. Clinical outcomes of interest were OM and NRM through day 365 after allo-HSCT. The cumulative incidence of CMV DNAemia in this cohort was 52.6%. A total of 306 out of 382 patients with CMV DNAemia received preemptive antiviral therapy (PET). PET use for CMV DNAemia, but not the occurrence of CMV DNAemia, taken as a qualitative variable, was associated with increased OM and NRM in univariate but not in adjusted models. A subcohort analysis including patients monitored by the COBAS Ampliprep/COBAS Taqman CMV Test showed that OM and NRM were comparable in patients in whom either low or high plasma CMV DNA threshold (<500 vs ≥500 IU/mL) was used for PET initiation. In conclusion, CMV DNAemia was not associated with increased OM and NRM in allo-HSCT recipients. The potential impact of PET use on mortality was not proven but merits further research.  相似文献   
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Archives of Sexual Behavior - Gender variance is a broad term used to describe gender non-conforming behaviors. Past studies have used the parental response to Child Behavior Checklist (CBCL) Item...  相似文献   
59.
We recently described the cloning of a fifth member of the 5-hydroxytryptamine (5-HT)1 (serotonin1) receptor class that inhibits adenylyl cyclase, namely the human 5-HT1F receptor (Adham et al. 1993 a). In the present study we have examined in greater detail the functional coupling of the 5-HT1F receptor in two different cell lines, NIH-3T3 and LM(tk) fibroblasts (receptor densities of 1.7 and 4.4 pmol/mg protein, respectively). The maximal inhibitory response elicited by 5-HT was significantly greater in NIH-3T3 as compared to LM(tk) cells, whereas the EC50 values were comparable.To investigate the relationship between receptor occupancy and inhibition of cAMP accumulation mediated by 5-HT1F receptors in NIH-3T3 cells (and hence the degree of receptor reserve), we used the irreversible receptor antagonist N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ). The half-maximal response required only about 10% receptor occupancy, consistent with a receptor reserve of 90% (88±2.1%, n = 4) for 5-HT-induced inhibition of FSCA. Despite the presence of such a high degree of receptor reserve, a range of intrinsic activities was displayed by structurally diverse classes of compounds. For example, sumatriptan and lysergol were as efficacious as 5-HT itself and thus acted as full agonists, whereas metergoline and 1-NP behaved as partial agonists and as shown previously (Adham et al. 1993a), methiothepin was a silent antagonist (Kb = 438 nM).We have also investigated activation of additional signal transduction pathways by the 5-HT1F receptor and found that the responses differ in the two cell lines with respect to stimulation of phospholipase C. For example, in NIH-3T3 cells no elevation of inositol phosphates (IP) of [Ca2+]i was observed even at very high agonist concentrations (100 M). In contrast, in LM(tk) cells concentrations of 5-HT as low as 10 nM induced stimulation of IP and a rapid increase of [Ca2+]i. The 5-HT1F receptor failed to alter arachidonic acid release in either cell line.The maximal increase in IP accumulation in LM(tk) cells was modest, averaging about 100% above basal. The increases of IP and [Ca2+]i required 5-HT concentrations less than one order of magnitude greater than those inhibiting FSCA (EC50 = 17, 55 and 8 nM, respectively), and both responses were blocked by 100 M methiothepin. All three responses (cAMP, IP, and [Ca2+]i) were sensitive to pertussis toxin pre-treatment, suggesting the involvement of Gi/Go protein(s) in these signal transduction pathways. [Ca2+]i was also elevated by sumatriptan, which may provide a mechanism by which this drug causes constriction of the vasculature. In conclusion, these data indicate that the human 5-HT1F receptor can couple to multiple effectors, and that this coupling is cell-type dependent.Abbreviations FSCA forskolin-stimulated cAMP accumulation - [Ca2+] intracellular free calcium concentration - AA arachidonic acid - EEDQ N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline - CHO chinese hamster ovary cell - LM(tk) mouse fibroblast cell - Bmax maximal binding site density - Ki apparent dissociation constant obtained from competition binding studies - G protein guanine nucleotide-binding protein - HBS HEPES-buffered saline - IP inositol phosphates - IP3 inositol 1,4,5 trisphosphate - PLC phospholipase C - Kb antagonist dissociation constant - Kd equilibrium dissociation constant - N-1F-6 stable NIH-3T3 cells expressing the cloned 5-HT1F receptor - L-1F-3 stable LM(tk) cells expressing the cloned 5-HT1F receptor - PTX pertussis toxin - BSA bovine serum albumin - METH methiothepin - SUMA sumatriptan - 5-MeO-DMT 5-methoxy-N,N-dimethyltryptamine - 1-NP 1-(1-napthyl)piperazine - 5-CT 5-carboxyamidotryptamine Correspondence to: N. Adham at the above address  相似文献   
60.
Three different domains of behavioral action of ethanol (ETOH) were examined in a battery of seven inbred strains and in the selectively bred Long-Sleep (LS) and Short-Sleep (SS) mice. Sedative effects were examined with the loss of the righting reflex test at 3.8 g/kg. The variation among inbred strains was only half the size of the difference between LS and SS mice which were selectively bred for extremes in this phenotype; such a result is expected for phenotypes controlled polygenically. Blood ETOH levels at waking from the narcosis also showed a range of differences among the inbred strains that was less than the LS/SS difference. Ataxia was measured with the grid test, and the inbred strains fell into two groups, resembling the highly ataxic LS line, and the less ataxic SS line. Biphasic effects of ETOH on locomotor activity were strongly genotype dependent. Variation in degree of activation/disinhibition produced by doses up to 1.5 g/kg (IP) ranged from no activation, in the C57BL/6Abg strain, to a stimulation effect in the MOLD/RkAbg strain which was larger than that seen for SS mice. The patterns of strain differences for both ataxia and activation were highly different from the duration of loss of righting reflex measure, suggesting multiple independent genetically based sensitivities to ETOH.  相似文献   
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