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BACKGROUND AND OBJECTIVES: This study, which was approved by the University's Ethical committee, was conducted to investigate the effectiveness of Combined Low Intensity Laser Therapy/Phototherapy (CLILT) in alleviating the signs and symptoms of Delayed Onset Muscle Soreness (DOMS) over an 11-day period. STUDY DESIGN/MATERIALS AND METHODS: Thirty-six subjects (18 M: 18 F) were randomly allocated, under strictly controlled double-blind conditions, to one of three experimental conditions: Control, Placebo, and CLILT (660-950 nm; 11 J/cm2; pulsed at 73 Hz). DOMS was induced in a standardised fashion in the non-dominant elbow flexors using repeated eccentric contractions until exhaustion was reached. Subjects returned on five consecutive days, and two days during the following week, for treatment according to group, and assessment of outcome variables including range of motion, pain, and tenderness. RESULTS: While analysis of results using repeated measures and one factor ANOVA with post-hoc tests showed significant changes in all variables over time (P < 0.05) as a result of the induction procedure, there were no significant differences observed between groups. CONCLUSIONS: CLILT failed to show any beneficial treatment effect on DOMS, at least at the parameters used here. These results therefore provide no evidence for the claimed biostimulating effects of such therapy.  相似文献   
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Objective.

Antibiotic-sterilised homograft valves stored at 4 °C have been implanted in the subcoronary position in this unit since 1973. This study was undertaken in order to assess the longterm function of these valves.

Methods.

All 249 patients undergoing homograft aortic valve replacement (AVR) at the Wessex Cardiothoracic Centre between April 1973 and December 1994 were studied. Homograft valve sizes ranged from 15 mm to 28 mm internal diameter, 202 (81.1%) varying between 18 mm and 22 mm. The mean patient follow-up was 12.4 years with a total follow-up of 3096 patient-years. There were six early deaths (2.4%).

Results.

On actuarial analysis, survival was 78.5 ± 2.7% (1SE) at 10 years, 65.7 ± 3.3% at 15 years and 55.0 ± 3.9% at 20 years. The freedom from redo AVR was 87.9 ± 2.4% at 10 years, 71.7 ± 3.8% at 15 years and 49.7 ± 5.6% at 20 years. The freedom from structural degeneration was 85.5 ± 2.5% at 10 years, 63.6 ± 4.0% at 15 years and 41.9 ± 6.4% at 20 years. On multivariate analysis the risk of valve failure was significantly higher in younger patients (P < 0.0001) and in those who underwent aortic root tailoring (P = 0.024). The freedom from endocarditis was 98.4 ± 0.9% at 10 years, 96.2 ± 1.6% at 15 years and 95.1 ± 1.9% at 20 years. Of the 249 patients, 218 had an isolated homograft AVR and were not anticoagulated. In this group there were two possible thromboembolic events.

Conclusion.

As well as the established haemodynamic benefits, this study has shown that homograft AVR with antibiotic-sterilised 4 °C stored homograft valves implanted in the subcoronary position, offers good long-term results.  相似文献   
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CONTEXT: Although chest pain is widely considered a key symptom in the diagnosis of myocardial infarction (MI), not all patients with MI present with chest pain. The extent to which this phenomenon occurs is largely unknown. OBJECTIVES: To determine the frequency with which patients with MI present without chest pain and to examine their subsequent management and outcome. DESIGN: Prospective observational study. SETTING AND PATIENTS: A total of 434,877 patients with confirmed MI enrolled June 1994 to March 1998 in the National Registry of Myocardial Infarction 2, which includes 1674 hospitals in the United States. MAIN OUTCOME MEASURES: Prevalence of presentation without chest pain; clinical characteristics, treatment, and mortality among MI patients without chest pain vs those with chest pain. RESULTS: Of all patients diagnosed as having MI, 142,445 (33%) did not have chest pain on presentation to the hospital. This group of MI patients was, on average, 7 years older than those with chest pain (74.2 vs 66.9 years), with a higher proportion of women (49.0% vs 38.0%) and patients with diabetes mellitus (32.6% vs 25. 4%) or prior heart failure (26.4% vs 12.3%). Also, MI patients without chest pain had a longer delay before hospital presentation (mean, 7.9 vs 5.3 hours), were less likely to be diagnosed as having confirmed MI at the time of admission (22.2% vs 50.3%), and were less likely to receive thrombolysis or primary angioplasty (25.3% vs 74.0%), aspirin (60.4% vs 84.5%), beta-blockers (28.0% vs 48.0%), or heparin (53.4% vs 83.2%). Myocardial infarction patients without chest pain had a 23.3% in-hospital mortality rate compared with 9.3% among patients with chest pain (adjusted odds ratio for mortality, 2. 21 [95% confidence interval, 2.17-2.26]). CONCLUSIONS: Our results suggest that patients without chest pain on presentation represent a large segment of the MI population and are at increased risk for delays in seeking medical attention, less aggressive treatments, and in-hospital mortality. JAMA. 2000;283:3223-3229  相似文献   
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IntroductionAlthough homosexuality is a subject often addressed by the media, little is said about homosexuality in adolescents who are particularly affected by the question of sexual orientation. This work aims to study the mental health of adolescents who report being exclusively attracted to members of the same sex. We explore the evidence for an association between homosexuality and depression, suicide attempts, and consulting a psychiatrist or a psychologist.MethodsWe used data from the cross-sectional study “Adolescent Portraits – A Multicenter Epidemiological Survey in Schools in 2013” (CHU Fondation Vallée, Inserm CESP U1018). Data were gathered through the use of an anonymous, self-administered questionnaire (348 questions) given to students between the “4e” and “terminale school” years (comparable to the 8th and 12th grade in the U.S. education system) in three contrasting French geographical areas. The risk of depression was measured using the Adolescent Depression Rating Scale (ADRS).ResultsThe results reflect the survey responses provided by 15,235 young people. Of these, 1.5 % reported only being attracted to members of the same sex (homosexual group). This group contained twice as many girls as boys. Students who did not report sexual attraction, who reported bisexual attraction, or who did not answer the question were excluded from the results (830 students). In the homosexual group, 24 % presented with depression versus 11.5 % of those attracted exclusively to members of the opposite sex (heterosexual group). There is also a significant difference between sexes: 13.2 % of boys in the homosexual group were depressed compared to 29.3 % of girls in the same group; 6.7 % of boys in the heterosexual group reported being depressed versus 16.1 % of girls in the same group. In the heterosexual group, 10.7 % of respondents reported having already made at least one suicide attempt versus 20.7 % of those in the homosexual group. There was a difference according to sex, since 6.3 % of boys in the heterosexual group had a history of attempted suicide versus 14.9 % of girls in the same group. This gap disappeared completely within the homosexual group, as 21.4 % of boys and 20.4 % of girls had already made at least one suicide attempt at the time of the survey. Depressed adolescents in the homosexual group also reported a higher number of previous suicide attempts than those in the heterosexual group (46.9 % versus 31.6 %). In terms of sex, 25.3 % of depressed boys in the heterosexual group made at least one suicide attempt versus 34.1 % of girls. In the homosexual group, 44.4 % of depressed boys reported having made at least one suicide attempt versus 47.5 % of depressed girls. Adolescents in the homosexual group were significantly more likely to report having consulted a psychiatrist or psychologist than those in the heterosexual group (14.6 % versus 6.5 %), regardless of sex (16.7 % versus 4.7 % for boys; 13.5 % versus 8.2 % for girls). This difference was also found among depressed subjects (26.0 % in the homosexual group versus 15.4 % in the heterosexual group). Sexual activity (having already had sex) was higher in the homosexual group than in the heterosexual group (53.7 % versus 37.5 %), and this difference remained significant after adjusting for age. Fifty percent of the sexually active homosexual respondents reported having engaged in sexual activity of a homosexual nature versus 0.7 % of sexually active heterosexual respondents. In the homosexual group, mental suffering appeared to be more severe among sexually active subjects, in terms of dark thoughts (64 % versus 46 %) and a prior history of attempted suicide (29.3 % versus 10 %), but not in terms of depression (27.9 % versus 18.9 %; NS).ConclusionYoung people who reported being exclusively attracted to members of the same sex presented a higher level of mental distress compared to those who reported being attracted to members of the opposite sex. This was especially the case for boys. These findings led to the identification of risk and protective factors that can inform the development of appropriate preventive measures.  相似文献   
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Porokeratosis ptychotropica is an unusual variant of porokeratosis characterized by papules and plaques located on the buttocks and gluteal cleft and showing multiple coronoid lamellae on histology. In this case report, we present the longitudinal clinical course of porokeratosis ptychotropica in a pediatric patient with individual red-brown hyperkeratotic lesions that enlarged and became confluent prior to surgical intervention. We also discuss the etiology of porokeratosis ptychotropica and review current as well as future treatment options for the disease.  相似文献   
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