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21.

Background  

Recent studies have reported the clinical importance of CYP2C19 and ABCB1 polymorphisms in an individualized approach to clopidogrel treatment. The aims of this study were to evaluate the frequencies of CYP2C19 and ABCB1 polymorphisms and to identify the clopidogrel-predicted metabolic phenotypes according to ethnic groups in a sample of individuals representative of a highly admixtured population.  相似文献   
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Two patients with growth hormone (GH) gene deletions were treated with recombinant insulin-like growth factor-I (IGF-I) (80-240 (microg/kg/day) and the effects on bone mass and body composition were compared to administration of GH (0.075 U/kg/day) to 8 patients with idiopathic GH deficiency. Bone mass and body composition were measured by dual photon X-ray absorptiometry (DEXA ) before and 3 and 6 months after treatment with GH or IGF-I. Similar increases in growth velocities were observed after GH and IGF-I treatment. Treatment with GH resulted in prompt and significant reduction in body fat percentage (basal, 3 and 6 months: 22+/-10, 17+/-9, and 16+/-9%) whereas body fat percentage remained unchanged after IGF-I therapy (basal, 3 and 6 months: 49, 52 and 48% in patient 1 and 45, 42 and 43% in patient 2, respectively). Fat percentage remained elevated after 18 months of IGF-I treatment in patients 1 (51%) and 2 (44%), respectively. Lean mass and bone mineral content increased with GH and IGF-I therapies. We conclude that reduction of body fat measured by DEXA, observed after administration of GH but not after IGF-I treatment in these children with GH deficiency, suggests that the GH effect on body fat mass is not mediated by circulating IGF-I.  相似文献   
24.
AIMS: To assess the recanalization effects of post-myocardial infarction (MI) on left ventricular (LV) remodelling and contractility in relation to conservative therapy. METHODS AND RESULTS: Thirty-six patients with occluded infarct-related artery between 12 h and 14 days post-anterior MI were randomized to percutaneous coronary intervention (PCI group) or conservative therapy (no-PCI group). Magnetic resonance imaging was performed at enrollment and after 6 months. The left ventricle was divided into infarct, adjacent, and remote segments. There was no difference in relation to LV volume between groups at the 6 month follow-up. Change in LV ejection fraction was favourable to the PCI group: 5.00% vs. -0.76%, P=0.012. Change in circumferential shortening (Ecc) of the remote segments in the PCI group was significantly better than in the no-PCI group: -1.67+/-6.30% vs. 0.29+/-6.02%, P<0.001. Infarct size and LV mass were similar between groups. CONCLUSIONS: Late recanalization improved LV ejection fraction and myocardial contractility in late follow-up, but did not change the ventricular volumes. Improvement in the left ventricle global and regional contractility may benefit the long-term outcome in post-MI patients with sustained patency of the infarct-related artery.  相似文献   
25.
BACKGROUND: Controversy prevails regarding the existence of a correlation between the severity of coronary artery disease (CAD) and the extent and distribution of obesity. PURPOSE: To assess the correlation between total fat, truncal fat (TF), and lean mass, obtained with dual-energy X-ray absorptiometry (DEXA) and standard anthropomorphic indices (body mass index, waist circumference, waist-to-hip ratio) and to verify whether DEXA indices can predict the extent and severity of CAD. MATERIALS AND METHODS: Fifty-eight patients (19 females) consecutively referred for coronary angiography underwent physical examination and DEXA assessment of body composition. RESULTS: Of the 58 patients enrolled, 22 were overweight and 13 were obese. Significant CAD was found in 39 (67%) patients. DEXA-derived total mass and fat mass enabled us to distinguish overweight from obese patients (P<0.005), whereas just TF mass correlated with the number of diseased vessels after adjusting for body mass index, sex, age, and smoking habit (odds ratio, 8.68; 95% confidence interval: 1.02-74.10). CONCLUSION: TF determined by DEXA is independently related with CAD extension.  相似文献   
26.
BACKGROUND: In recent years several trials demonstrated the efficacy of implantable cardioverter-defibrillator (ICD) therapy for sudden cardiac death prevention and total mortality reduction in particular high-risk groups of patients. The aim of this review was to report the main epidemiological data and the most important clinical characteristics of patients enrolled in the Italian ICD Registry in the years 2001-2003. METHODS: The Italian ICD Registry--official member of the Italian Association of Arrhythmology and Cardiac Pacing (AIAC)--collects 85% of the data concerning the national ICD implantation activity, based on the European Implantable Defibrillator form (EURID). Data are validated for quality of information and uniqueness at the moment of data entry and in successive steps at the time of the annual analysis. RESULTS: The number of ICDs implanted in Italy has been continuing to increase during the last years according to the general trend in European and non-European countries: 2400 in the year 2001, 3934 in the year 2002, and 5318 in the year 2003. The number of ICDs per million of inhabitants in Italy was 42.1 in the year 2001 (+11.8% with respect to 2000), 69.0 in the year 2002 (+63.9% with respect to 2001), and 93.3 in the year 2003 (+35.2% with respect to 2002). The number of implanting centers increased progressively from 273 in the year 2001 to 304 in the year 2002, and 340 in the year 2003. The median age of patients treated with ICD implantation was 67 years in the years 2001-2002, 68 years in the year 2003. The prevalence of male patients was significantly higher (79.3% in 2001, 82.3% in 2002, and 81.4% in 2003). The main indication was syncope (25.5, 29.3, and 32.9% in the years 2001, 2002, and 2003, respectively), followed by palpitations (17.7, 18.5, and 16.4% in the years 2001, 2002, and 2003, respectively), and cardiac arrest (10.0, 13.1, and 16.5% in the years 2001, 2002, and 2003, respectively). The use of ICD in patients considered at risk but without history of sustained ventricular tachycardia had a 3-fold increase during the 3 years, from 6.4% in 2001 to 18.2% in 2003. Ventricular tachycardia was the main arrhythmia in 50.4 to 55.0% of cases, ventricular fibrillation in 13.5 to 18.1%, both in 4.1 to 6.5%. The vast majority of patients presented at the enrolment either a mild or severe reduction in ejection fraction (30 to 50%, < 30%). Amiodarone was administered alone or in combination with antiarrhythmics in 29.7 to 40.0% of patients. Single-chamber ICDs were implanted in the years 2002 and 2003 in 45.7 and 39.2% of patients, dual-chamber ICDs in 34.9 and 32.4%, biventricular ICDs in 19.4 and 28.4%, respectively. CONCLUSIONS: The ICD implantation rate in Italy increased significantly in the period 2001-2003, similarly to the trend in the other western countries and following the publication of controlled studies in the field of primary and secondary prevention of sudden cardiac death. The Italian ICD Registry showed during the last 3 years an important increase in prophylactic ICD utilization. A sophisticated ICD, including dual-chamber pacing or cardiac resynchronization therapy, was chosen in a high percentage of patients.  相似文献   
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28.
STUDY OBJECTIVE: To determine the steady-state, extracellular, and intracellular pulmonary disposition of moxifloxacin (MXF), levofloxacin (LEVO), and azithromycin (AZI) relative to that of the plasma over a 24-h dosing interval. DESIGN: Randomized, multicenter, open-label investigation. PATIENTS: Forty-seven older adults (mean [+/- SD] age, 62 +/- 13 years) undergoing diagnostic bronchoscopy. INTERVENTIONS: Oral administration of MXF, 400 mg, LEVO, 500 mg daily for five doses, or AZI, 500 mg for one dose, then 250 mg daily for four doses. BAL and venipuncture were completed at 4, 8, 12, or 24 h following the administration of the last dose. MEASUREMENTS AND RESULTS: Steady-state MXF, LEVO, and AZI concentrations were determined in the plasma, epithelial lining fluid (ELF), and alveolar macrophages (AMs). The concentrations of all three agents were greatest in the AMs followed by the ELF compared to the plasma. Plasma concentrations were similar to those previously reported with these agents. The mean ELF concentrations at 4, 8, 12, and 24 h were as follows: MXF, 11.7 +/- 11.9, 7.8 +/- 5.1, 10.5 +/- 3.7, and 5.7 +/- 6.3 micro g/mL, respectively; LEVO, 15.2 +/- 4.5, 10.2 +/- 6.7, 6.9 +/- 4.4, and 2.9 +/- 1.7 micro g/mL, respectively; and AZI, 0.6 +/- 0.4, 0.7 +/- 0.4, 0.9 +/- 0.5, and 0.9 +/- 0.7 micro g/mL, respectively. The AM concentrations at 4, 8, 12, and 24 h were as follows: MXF, 47.7 +/- 47.6, 123.3 +/- 126.4, 26.2 +/- 19.4, and 32.8 +/- 16.5 micro g/mL, respectively; LEVO, 28.5 +/- 30.2, 26.1 +/- 15.7, 28.3 +/- 12.6, and 8.2 +/- 6.1 micro g/mL, respectively; and AZI, 71.8 +/- 50.1, 73.8 +/- 75.3, 155.9 +/- 81.3, and 205.2 +/- 256.3 micro g/mL, respectively. CONCLUSIONS: The intrapulmonary concentrations of MXF, LEV, and AZI were superior to those obtained in the plasma. The AM concentrations of all agents studied were more than adequate relative to the minimum concentration required to inhibit 90% of the organism population (MIC(90)) of the common intracellular pathogens (< 1 micro g/mL). These data indicate that attainable extracellular concentrations of AZI are insufficient to reliably eradicate Streptococcus pneumoniae, based on the agent's current minimum inhibitory concentration profile, whereas the mean concentrations of MXF and LEVO in the ELF exceed the MIC(90) of the S pneumoniae population. Moreover, MXF concentrations exceeded the S pneumoniae susceptibility breakpoint (1.0 micro g/mL) at all time points, while 2 of 15 concentrations (13%) failed to maintain LEVO concentrations above the breakpoint (2.0 micro g/mL) throughout the dosing interval.  相似文献   
29.
OBJECTIVES: The purpose of this study was to assess the determinants of mortality in a large group of patients with ischemic cardiomyopathy who are treated medically and the impact of the extent of viable tissue on prognosis. BACKGROUND: Whether the presence of viability drives mortality in patients with ischemic cardiomyopathy who are treated medically and whether the extent of viability is important are issues that are currently unclear. METHODS: Two hundred sixty-one patients with ischemic cardiomyopathy underwent positron emission tomography (PET) for assessment of viability. Prospective follow-up was obtained. RESULTS: Ninety-four patients were revascularized and 167 were not. The cardiac death rate was significantly less in the revascularized patients as compared with medically treated patients (13% vs. 24%, p < 0.05). In the revascularized patients, there was a trend toward better survival in patients with viable myocardium as compared with nonviable myocardium (3.5-year survival, 85% and 75% respectively, p = NS). In the medically treated group, age (hazard ratio [HR] 2.1, 95% confidence interval [CI] 1.2 to 3.7), presence of left bundle branch block (HR 3.4, 95% CI 1.6 to 7.2) and extent of perfusion-metabolism mismatch on PET (HR 1.36, 95% CI 1.1 to 1.6) predicted cardiac death during a median follow-up period of 2.1 years. The risk of cardiac death was not significantly increased when the extent of mismatch was < or =20% (HR 0.97, 95% CI 0.46 to 2.05) but was significantly increased when the extent of mismatch was >20% (HR 3.21, 95% CI 1.38 to 7.49). CONCLUSIONS: Medically treated patients with ischemic cardiomyopathy and large areas of viable myocardium on PET are at high risk for cardiac death.  相似文献   
30.

Background

Subclinical inflammation mediated in part by interleukin (IL)-1β participates in peripheral insulin resistance and impaired pancreatic insulin secretion.

Objectives

The authors tested the hypothesis that the IL-1β inhibitor canakinumab reduces incident diabetes.

Methods

The authors randomized 10,061 patients with prior myocardial infarction and high-sensitivity C-reactive protein (hsCRP) ≥2 mg/l to placebo or canakinumab at doses of 50 mg, 150 mg, or 300 mg subcutaneously once every 3 months. The authors tested the effects of canakinumab on major cardiovascular events in patients with and without diabetes at baseline, and evaluated as a pre-specified analysis whether canakinumab would reduce the risk of adjudicated cases of new-onset type 2 diabetes among those with protocol-defined pre-diabetes at trial entry. The authors also evaluated the effect of canakinumab on fasting plasma glucose and glycosylated hemoglobin (HbA1c) in patients with and without established diabetes.

Results

Of the participants, 4,057 (40.3%) had baseline diabetes, 4,960 (49.3%) had pre-diabetes, and 1,044 (10.4%) had normal glucose levels. Among those without diabetes, increasing tertiles of hsCRP at baseline associated with an increased risk of developing diabetes during the median follow-up period of 3.7 years (incidence rates 3.2, 4.1, and 4.4 per 100 person-years; p = 0.003). Canakinumab 150 mg as compared with placebo had similar magnitude effects on major cardiovascular event rates among those with diabetes (hazard ratio [HR]: 0.85; 95% confidence interval [CI]: 0.70 to 1.03), pre-diabetes (HR: 0.86; 95% CI: 0.70 to 1.06), and normoglycemia (HR: 0.81; 95% CI: 0.49 to 1.35). Despite large reductions in hsCRP and IL-6, canakinumab did not reduce the incidence of new-onset diabetes, with rates per 100 person-years in the placebo, 50 mg, 150 mg, and 300 mg canakinumab groups of 4.2, 4.2, 4.4, and 4.1, respectively (log-rank p = 0.84). The HR comparing all canakinumab doses to placebo was 1.02 (95% CI: 0.87 to 1.19; p = 0.82). Canakinumab reduced HbA1c during the first 6 to 9 months of treatment, but no consistent long-term benefits on HbA1c or fasting plasma glucose were observed.

Conclusions

Although IL-1β inhibition with canakinumab had similar effects on major cardiovascular events among those with and without diabetes, treatment over a median period of 3.7 years did not reduce incident diabetes. (Canakinumab Anti-inflammatory Thrombosis Outcomes Study [CANTOS]; NCT01327846)  相似文献   
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