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Plankeel JF  McMullen B  MacIntyre NR 《Chest》2005,127(1):110-116
STUDY OBJECTIVES: Pulmonary rehabilitation (PR) that includes exercise training can improve exercise tolerance and quality of life for patients with COPD. However, the degree of benefit from PR is variable. We hypothesized that the exercise response to PR varies depending on the initial factors that limit exercise. DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS: We retrospectively analyzed the change in exercise capacity after PR in 290 nonhypoxemic patients with COPD. We classified patients into the following subgroups based on the primary limitation seen on initial exercise testing: (1) ventilatory-limited (VL); (2) cardiovascular-limited (CVL); (3) mixed ventilatory/cardiovascular-limited (VLCVL); and (4) non-cardiopulmonary-limited (NL). We compared outcomes among subgroups. RESULTS: In the entire study population, PR led to increased timed walk distance (30.3%; p < 0.0001) and maximal oxygen consumption (VO2max) [84.8 mL/min; p < 0.0001]. Stepwise multiple regression selected age, ventilatory reserve at peak exercise, and exercise arterial oxygen pressure as individual predictors of improvement in VO2max. VO2max increased in the VL subgroup (30.4 mL/min; p = 0.008), the CVL subgroup (109.0 mL/min; p < 0.0001), the mixed VLCVL subgroup (61.3 mL/min; p < 0.0001), and NL subgroups (110.5 L/min; p < 0.0001). The improvement in VO2max was greater in the CVL subgroup than in the VL subgroup (p < 0.0001). Timed walk distance improved to a similar degree in all subgroups (26 to 36%). CONCLUSIONS: Patients with nonventilatory exercise limitations experience the greatest increase in VO2max after PR. However, even patients with severe ventilatory limitation can improve exercise tolerance with PR.  相似文献   
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AIM: Elderly patients have an increased incidence of ischaemic dilated cardiomyopathy often related to diffuse coronary artery disease. Trimetazidine protects ischaemic myocardium by improving the myocardial energy utilisation during myocardial ischaemia. Aim of the present study was to evaluate the effects of trimetazidine on left ventricular (LV) function in elderly patients with ischaemic heart disease and reduced LV function. METHODS: Forty seven elderly patients (40 males and 7 females, mean age 78+/-3 years) were randomised to receive, in addition to standard therapy, either trimetazidine or placebo and were evaluated by echocardiography at baseline and after 6 months. RESULTS: Trimetazidine and placebo had no effect on either blood pressure or heart rate (SBP 2+/-5 vs 4+/-6 mmHg, DBP -1+/-6 vs 3+/-4 mmHg, HR -3+/-7 vs 5+/-9 bpm, trimetazidine and placebo compared to baseline, respectively). At the end of the study patients randomised to trimetazidine showed a significant greater left ventricular function and smaller left ventricular diastolic and systolic diameters and volume indices compared to patients receiving placebo (LVEF: 34.4+/-2.3% vs 27+/-2.8%, p<0.0001; LVEDD: 58.6+/-1.9 mm vs 64+/-1.7 mm, p<0.0001; LVESD: 44.5+/-1.1 vs 50+/-0.8 mm, p<0.0001). A significant smaller wall motion score index was detected in trimetazidine-treated patients compared to those allocated to placebo (1.24+/-0.12 vs 1.45+/-0.19, p<0.01), the percentage change in LVEF compared to baseline was also significantly greater in trimetazidine-treated patients. Diastolic function significantly improved in the trimetazidine group while it remained unchanged in the placebo group. At follow-up evaluation, patients receiving trimetazidine showed a greater improvement in angina and NYHA class than patients allocated to placebo. Quality of life significantly improved in all patients treated with trimetazidine while remained unchanged in those allocated to placebo. CONCLUSION: In elderly patients with ischaemic cardiomyopathy trimetazidine in addition to standard medical therapy has a beneficial effect on LV systolic and diastolic function, and improves quality of life.  相似文献   
995.
The clinical syndromes of hemophagocytic lymphohistiocytosis (HLH) and macrophage activation syndrome (MAS) are both characterized by dysregulated inflammation with prolonged fever, hepatosplenomegaly, coagulopathy, hematologic cytopenias, and evidence of hemophagocytosis in the bone marrow or liver. While HLH is either inherited or acquired, children with severe rheumatic diseases, most notably systemic juvenile idiopathic arthritis, are at risk for MAS. The phenotypic similarity between HLH and MAS raises the possibility that they share common pathogenetic mechanisms. Familial forms of HLH have been attributed to mutations in the genes encoding perforin (PRF1) and Munc13-4 (UNC13D), among others, and are characterized by defective cytotoxic lymphocyte function. While some patients with systemic JIA have decreased levels of perforin protein expression and natural killer (NK) cell function, mutations of HLH-associated genes in patients with systemic JIA have not been reported. We report the case of an 8-year-old girl with systemic JIA without MAS who was found to have compound heterozygous mutations of UNC13D and reduced NK cell cytotoxic function. This case broadens the range of clinical phenotypes attributable to UNC13D mutations and offers new insights into the etiology and pathogenesis of systemic JIA.  相似文献   
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The Fc receptors on mononuclear cells were investigated by a rosette technique in which human erythrocytes were sensitized with a known number of molecules of anti-Rh antibodies (IgG1 or IgG3). The number of IgG molecules was quantitated by a radiometric antiglobulin test. The present quantitative evaluation reveals that (1) there is a logarithmic relationship between the proportion of rosettes and the amount of erythrocyte-bound immunoglobulin for both types of mononuclear cells, and for both subclasses; (2) similar percentage of rosettes can be obtained with fewer IgG3 than IgG1 molecules (about 1:4); (3) for a given number of erythrocyte-bound immunoglobulins a higher percentage of rosettes is observed with monocytes than with lymphocytes (ratios of about 3:1 for IgG1 and 5:1 for IgG3); (4) the minimum number of IgG3 molecules for adherence is 180-460 for monocytes, 520-1,300 for lymphocytes, whilst for IgG1 the numbers are 1,180-4,300 for monocytes and 3,400-14,200 for lymphocytes; (5) the minimum levels of sensitization by alloantibodies for adherence should be detectable by the antiglobulin test.  相似文献   
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Background

The association between diagnosed acute ST-elevation myocardial infarction (STEMI) and hockey games in the Canadian population is unknown.

Methods

We retrospectively analyzed the association between hockey games of the National Hockey League Montreal Canadiens and daily hospital admissions for acute STEMI at the Montreal Heart Institute, Canada.

Results

Between June 2010 and December 2014, a total of 2199 patients (25.9% women; mean age, 62.6 ± 12.4 years) were admitted for acute STEMI. An increase in STEMI admissions was observed the day after a hockey game of the Montreal Canadiens in the overall population (from 1.3 ± 1.2 to 1.5 ± 1.3), however, this difference was not significant (P = 0.1). The number of STEMI admissions increased significantly from 0.9 ± 1.0 to 1.2 ± 1.0 per day in men (P = 0.04), but not in women (P = 0.7). The association between ice hockey matches and STEMI admission rates was strongest after a victory of the Montreal Canadiens. Accordingly, an increased risk for the occurrence of STEMI was observed in the overall population (hazard ratio [HR], 1.15; 95% confidence interval [CI], 1.0-1.3; P = 0.037) when the Montreal Canadiens won a match. This association was present in men (HR, 1.2; 95% CI, 1.03-1.4; P = 0.02) but not in women (P = 0.87), with a most pronounced effect seen in younger men (younger than 55 years; HR, 1.4; 95% CI, 1.1-1.8; P = 0.009).

Conclusions

Although a weak association between hockey games and hospital admissions for STEMI was found in our overall population, the event of a hockey game significantly increased the risk for STEMI in younger men. Preventive measures targeting behavioural changes could positively affect this risk.  相似文献   
1000.
PURPOSE: We determine the main outcome effects of a 12-month computer-mediated automated interactive voice response (IVR) intervention designed to assist family caregivers managing persons with disruptive behaviors related to Alzheimer's disease (AD). DESIGN AND METHODS: We conducted a randomized controlled study of 100 caregivers, 51 in the usual care control group and 49 in the technology intervention group, who received yearlong access to an IVR-mediated system. The system provided caregiver stress monitoring and counseling information, personal voice-mail linkage to AD experts, a voice-mail telephone support group, and a distraction call for care recipients. We conducted analyses by using a repeated measures approach for longitudinal data and an intention-to-treat analytic approach. Outcomes included the caregiver's appraisal of the bothersome nature of caregiving, anxiety, depression, and mastery at baseline, 6, 12, and 18 months. RESULTS: There was a significant intervention effect as hypothesized for participants with lower mastery at baseline on all three outcomes: bother (p =.04), anxiety (p =.01), and depression (p =.007). Additionally, wives exhibited a significant intervention effect in the reduction of the bothersome nature of caregiving (p =.02). IMPLICATIONS: Wives who exhibited low mastery and high anxiety benefited the most from the automated telecare intervention. Findings suggest that, to optimize outcome effects, similar interventions should be tailored to match the users' characteristics and preferences.  相似文献   
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