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991.
992.
PurposeThe American Board of Medical Genetics and Genomics (ABMGG) certifying examinations (CEs) are designed to assess relevant basic knowledge, clinical knowledge, and diagnostic skills of board-eligible candidates in primary specialty areas. The ABMGG in-training examinations (ITEs) provide formative feedback regarding knowledge and learning over time and assess readiness to attempt board certification. This study addresses the validity of the ABMGG ITE by evaluating its relationship with performance on CE utilizing established psychometric approaches.MethodsStatistical analysis included bivariate Pearson correlation coefficients and linear regression to evaluate the strength of associations between ITE scores and CE scores. Logistic regression was used to assess the association between ITE scores and the probability of passing each CE.ResultsLogistic regression results indicated that ITE scores accounted for 22% to 44% of the variability in CE outcomes. Across 3 certification cycles, for every 1-point increase in ITE scores, the odds ratio for earning a passing score increased by a factor of 1.12 to 1.20 for the general CE, 1.14 to 1.25 for the clinical CE, and 1.12 to 1.20 for the laboratory CEs.ConclusionThe findings show a positive correlation between performance on the ITE examination and performance on and passing the ABMGG CE.  相似文献   
993.
Aim  Clinical trials have demonstrated the efficacy of the tetravalent human papillomavirus (HPV) vaccination in the prevention of cervical cancer and genital warts associated with HPV types 6, 11, 16 and 18. We used an empirically calibrated Markov cohort model of the natural history of HPV to assess the cost-effectiveness of the vaccine administered to 12-year-old girls alongside existing cervical screening programmes in Germany. Subjects and methods  The model estimated cervical cancer (CC), cervical intraepithelial neoplasia (CIN) and genital wart lifetime risks and total lifetime health care costs, life years gained and quality-adjusted life years (QALY) gained. The analysis was conducted from the perspective of the German health care payer. Results  In the base case (considering a lifetime duration of protection and 100% efficacy) it was estimated that 2,835 cervical cancer cases and 679 deaths could be prevented among a cohort of 400,000, at an incremental cost per QALY gained of 10,530 €. A total of 120 girls needed to be vaccinated to prevent 1 case of CC. Cost-effectiveness is sensitive to a duration of protection of less than 20 years and to the discount rate for costs and benefits. Conclusion  A policy of vaccinating adolescent girls has been recommended by the German Standing Committee on Vaccinations. This study has demonstrated that such a policy is cost-effective based on thresholds of cost-effectiveness that apply in Germany.  相似文献   
994.
995.
996.
Apathy and the processing of novelty in schizophrenia   总被引:1,自引:0,他引:1  
Apathy is a common negative symptom in schizophrenia that has been associated with poor medication compliance and treatment outcome. Recent studies in neurological patients have observed an association between apathy and reduced attention to novel stimuli. We evaluated whether patients with schizophrenia demonstrate a similar relationship. Participants included 20 patients with schizophrenia and 20 healthy comparison subjects matched for age, sex, handedness, and parental education. A self-paced visual novelty task was presented which assessed the duration that participants looked at frequent standard stimuli, infrequent target stimuli, and novel stimuli. Attention to novelty was defined as the duration of viewing novel relative to standard stimuli. Apathy was assessed with the Marin Apathy Evaluation Scale. Results revealed significantly greater self- and informant-reported apathy, slower reaction time to target stimuli, and longer viewing times to the stimuli, but not reduced attention to the novel stimuli, in the patient group. Although greater self-report of apathy was associated with longer viewing times for all stimuli in the patient group, this was accounted for by depressed mood. The present findings indicate that schizophrenia is associated with slowed information processing, but do not support the hypothesis that apathy in schizophrenia is associated with abnormal processing of novelty.  相似文献   
997.
Several observational studies have demonstrated that serum levels of minerals and parathyroid hormone (PTH) have U- or J-shaped associations with mortality in maintenance hemodialysis patients, but the relationship between serum alkaline phosphatase (AlkPhos) and risk for all-cause or cardiovascular death is unknown. In this study, a 3-yr cohort of 73,960 hemodialysis patients in DaVita outpatient dialysis were studied, and the hazard ratios for all-cause and cardiovascular death were higher across 20-U/L increments of AlkPhos, including within the various strata of intact PTH and serum aspartate aminotransferase. In the fully adjusted model, which accounted for demographics, comorbidity, surrogates of malnutrition and inflammation, minerals, PTH, and aspartate aminotransferase, AlkPhos > or =120 U/L was associated with a hazard ratio for death of 1.25 (95% confidence interval 1.21 to 1.29; P < 0.001). This association remained among diverse subgroups of hemodialysis patients, including those positive for hepatitis C antibody. A rise in AlkPhos by 10 U/L during the first 6 mo was incrementally associated with increased risk for death during the subsequent 2.5 yr. In summary, high levels of serum AlkPhos, especially >120 U/L, are associated with mortality among hemodialysis patients. Prospective controlled trials will be necessary to test whether serum AlkPhos measurements could be used to improve the management of renal osteodystrophy.  相似文献   
998.
Many children who neutralize phonemic contrasts in production exhibit diminished perception of the same contrasts. It is usually difficult to determine whether the perception deficit caused the production error, or vice versa; however, the direction of causation has implications for treatment planning. This study examines perception-production relationships in the phenomenon of neutralization in strong position, where children neutralize only in perceptually salient contexts. To test a hypothesis that this phenomenon arises from a child-specific pattern of perceptual sensitivity, a non-word discrimination task was administered to a 4-year-old boy with neutralization in strong position in production. Contrary to the perceptual hypothesis, his discrimination accuracy was greatest for contrasts in initial/strong position, where his production errors occurred. Independent of position, however, his perception of a phonemic contrast he neutralized was decreased relative to other contrasts. This case is argued to constitute evidence that a primary production deficit can cause decreased perceptual ability.  相似文献   
999.
While communicating hydrocephalus (CH) is often characterized by increased pulsatile flow of cerebrospinal fluid (CSF) in the cerebral aqueduct, a clear-cut explanation for this phenomenon is lacking. Increased pulsatility of the entire cerebral vasculature including the cortical capillaries has been suggested as a causative mechanism. To test this theory, we used two-photon microscopy to measure flow pulsatility in neocortical capillaries 40 to 500 μm below the pial surface in adult rats with CH at 5 to 7 days (acute, n=8) and 3 to 5 weeks (chronic, n=5) after induction compared with intact controls (n=9). Averaging over all cortical depths, no increase in capillary pulsatility occurred in acute (pulsatility index (PI): 0.15±0.06) or chronic (0.14±0.05) CH animals compared with controls (0.18±0.07; P=0.07). More specifically, PI increased significantly with cortical depth in controls (r=0.35, P<0.001), but no such increase occurred in acute (r=0.06, P=0.3) or chronic (r=0.05, P=0.5) CH. Pulsatile CSF aqueductal flow, in contrast, was elevated 10- to 500-fold compared with controls. We conclude that even in the presence of markedly elevated pulsatile CSF flow in the aqueduct, there is no concurrent increase in microvascular pulsatile flow.  相似文献   
1000.
Estrogen therapy used in combination with selective serotonin reuptake inhibitor (SSRI) treatment improves SSRI efficacy for the treatment of mood disorders. Desensitization of serotonin 1A (5-HT(1A)) receptors, which takes one to two weeks to develop in animals, is necessary for SSRI therapeutic efficacy. Estradiol modifies 5-HT(1A) receptor signaling and induces a partial desensitization in the paraventricular nucleus (PVN) of the rat within two days, but the mechanisms underlying this effect are currently unknown. The purpose of this study was to identify the estrogen receptor necessary for estradiol-induced 5-HT(1A) receptor desensitization. We previously showed that estrogen receptor β is not necessary for 5-HT(1A) receptor desensitization and that selective activation of estrogen receptor GPR30 mimics the effects of estradiol in rat PVN. Here, we used a recombinant adenovirus containing GPR30 siRNAs to decrease GPR30 expression in the PVN. Reduction of GPR30 prevented estradiol-induced desensitization of 5-HT(1A) receptor as measured by hormonal responses to the selective 5-HT(1A) receptor agonist, (+)8-OH-DPAT. To determine the possible mechanisms underlying these effects, we investigated protein and mRNA levels of 5-HT(1A) receptor signaling components including 5-HT(1A) receptor, Gαz, and RGSz1. We found that two days of estradiol increased protein and mRNA expression of RGSz1, and decreased 5-HT(1A) receptor protein but increased 5-HT(1A) mRNA; GPR30 knockdown prevented the estradiol-induced changes in 5-HT(1A) receptor protein in the PVN. Taken together, these data demonstrate that GPR30 is necessary for estradiol-induced changes in the 5-HT(1A) receptor signaling pathway and desensitization of 5-HT(1A) receptor signaling.  相似文献   
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