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61.
BACKGROUND: Cardioversion of atrial fibrillation (AF) carries the risk of thromboembolic complications and, therefore, anticoagulation therapy is routinely administered before and after this procedure. In patients with permanent AF who undergo implantation of cardioverter-defibrillator (ICD), anticoagulants are usually withdrawn during the perioperative period. However, in some patients sinus rhythm may be restored during defibrillation threshold (DFT) testing which potentially may increase the risk of thromboembolic complications. AIM: To assess the frequency of sinus rhythm restoration during ICD implantation in patients with permanent AF and the rate of both thromboembolic events and local bleeding complications which may occur due to temporary withdrawal of anticoagulation therapy and its re-initiation early after the procedure. METHODS: Permanent AF was present in 23 (12%) of 193 patients selected for ICD implantation. All patients received prolonged oral anticoagulation according to the generally accepted standards. Anticoagulation therapy was stopped few days before the procedure and replaced by low molecular weight heparin which was administered up to 24 hours before ICD implantation and re-initiated 12-24 hours afterwards. RESULTS: During DFT testing sinus rhythm was restored in 5 (21.7%) patients with AF. Clinical and DFT characteristics were similar in those who were converted to sinus rhythm and those who remained in AF. No thromboembolic events were noted in either group. Local haematoma at the site of ICD implantation occurred in two (8%) patients. CONCLUSIONS: Sinus rhythm was restored in 21.7% of patients with permanent AF who underwent ICD implantation. Temporary withdrawal of anticoagulation therapy did not increase the risk of thromboembolic complications, however, its early re-initiation after implantation resulted in an increase in local bleeding complication rate.  相似文献   
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OBJECTIVES: The goal of this study was to determine if a low-dose combination of the angiotensin-converting enzyme inhibitor perindopril (Per) and the diuretic indapamide (Ind) reduces central (thoracic aorta, carotid artery) as well as brachial systolic blood pressure (SBP) more than the beta-blocker atenolol and to determine the hemodynamic factors influencing independently brachial and central SBP: pulse wave velocity (PWV) and pattern of wave reflections. BACKGROUND: In high cardiovascular risk populations, angiotensin blockade improves survival without affecting brachial SBP and diastolic blood pressure (DBP). Whether central SBP, which is physiologically lower than brachial SBP, is significantly reduced has never been investigated. METHODS: This study was a double-blind randomized trial for one year in patients with essential hypertension. RESULTS: For a similar DBP reduction, Per/Ind decreased SBP significantly more than atenolol, with a more pronounced reduction for central than for brachial SBP. After one year, the difference between brachial and central SBP was maintained by Per/Ind (8.28 +/- 1.53 mm Hg) and significantly attenuated by atenolol (0.29 +/- 1.61 mm Hg). Under atenolol, the principal factor modulating SBP reduction was mean blood pressure. Under Per/Ind, this parameter played a minor role, and the central SBP reduction implied a major role for disturbed PWV and wave reflections. CONCLUSIONS: Under Per/Ind, but not atenolol, normalization of brachial SBP is achieved with a significantly greater reduction of central SBP. This hemodynamic profile reflects changes of wave reflections issued from distal arterial and arteriolar territory, where Per/Ind, but not atenolol, is known to improve vessel wall structure.  相似文献   
64.
The aim of the study was to develop simple algorithm for non-invasive estimating probability of the presence of CAD to optimize indications for cardiac catheterization. A prospective collection of clinical, electrocardiography (ECG), exercise electrocardiography (EE), dobutamine stress echocardiography (SE) and catheterization data was performed. All patients (n = 551, 65% male) complaining of chest pain, without prior history of myocardial infarction undergone EE (regarded as positive on the basis of > or = 1 mm ST-depression) SE (ischemia was defined as new or worsening wall motion abnormalities using a 16-segment model) and coronary angiography (CA): CAD was defined as > or = 50% narrowing of at least one major vessel. Two algorithms were developed with the use of probability analysis by computer program which employs Bayes' theory. They incorporated pretest variables: (age, gender, chest pain classification according to Diamond), ECG and results of one or two non-invasive test: EE and (or) SE. The studied population was divided into 3 groups on the basis of pretest likelihood of CAD: 1. low (< 10%), 2. intermediate (10-70%, in man divided into intermediate--low.: 10-29% and intermediate--high: 30-70%) and 3. high (> 70%). RESULTS: The prevalence of CAD in studied population was 61%. The sensitivity of the algorithm is 96% and specificity was 44%. Sensitivity and specificity of EE and SE was respectively: 93%, 21% and 85%, 69%). CONCLUSIONS: 1. An algorithm derived in our study is simple and may be useful in decision making that relates to CA. 2. We showed that when the likelihood of CAD is high on the basis of initial evaluation, diagnostic non-invasive testing is not indicated before CA, when the probability is intermediate or low, implementation of first choice test should be different in women (SE) and men (EE).  相似文献   
65.

Objectives

The authors sought to compare outcomes of patients with myocardial infarction and cardiogenic shock (CS) treated with percutaneous coronary intervention (PCI) with or without intra-aortic balloon pump (IABP) support according to final epicardial flow in the infarct-related artery.

Background

A routine use of IABP is contraindicated in patients with myocardial infarction and CS. There are no data regarding the subpopulation of patients who may benefit from such support besides patients with mechanical complications of myocardial infarction.

Methods

Prospective nationwide registry data of patients with myocardial infarction and CS treated with PCI between 2003 and 2014 were analyzed. Patients were initially stratified into 2 groups according to final infarct-related artery Thrombolysis In Myocardial Infarction (TIMI) flow grade after PCI: those with successful primary PCI (TIMI flow grades 2 or 3) and those with unsuccessful primary PCI (TIMI flow grades 0 or 1). Outcomes of patients with or without IABP treatment in each group were analyzed and compared.

Results

In the unsuccessful PCI group, patients in whom IABP was applied had lower in-hospital, 30-day, and 12-month mortality. IABP support in this group of patients was an independent predictor of lower 30-day mortality (hazard ratio [HR]: 0.72; 95% confidence interval [CI]: 0.59 to 0.89; p = 0.002). Conversely, in patients with successful PCI, IABP was an independent predictor of higher 30-day mortality (HR: 1.18; 95% CI: 1.08 to 1.30; p = 0.0004).

Conclusions

IABP is associated with a lower risk of 30-day mortality in patients with myocardial infarction complicated by CS, in whom primary PCI was unsuccessful.  相似文献   
66.
BACKGROUND: The coexistence of peripheral artery disease (PAD) and multilevel atherosclerosis increases death and stroke rates in patients with coronary artery disease (CAD). Due to many comorbidities these patients are often treated conservatively without revascularisation. AIM: To investigate whether complex percutaneous cardiovascular interventions for CAD and PAD may improve prognosis and long-term outcome in this group of patients. METHODS: We studied consecutive patients treated for symptomatic CAD who also had chronic PAD. The primary cause of hospital admission for all our patients was non-ST elevation acute coronary syndrome (NSTE ACS). All percutaneous peripheral interventions were performed during one hospital stay (index hospitalisation). Major adverse cardio- and cerebrovascular events (MACCE) during follow-up were defined as follows: death (cardiac and non-cardiac), myocardial infarction (MI), urgent revascularisation (surgical or repeat PCI, peripheral percutaneous intervention), stroke/TIA or amputation. RESULTS: We performed 109 interventions in 78 consecutive patients with chronic peripheral artery stenoses and occlusions. The average age was 61.5+/-8.6 years and the majority were males (80%). Preinterventional angiography showed occlusions that involved the common iliac artery in 28 (36%) patients, the external iliac artery in 16 (21%) patients, internal iliac artery in 2 (3%) patients, and superficial femoral artery in 63 (81%) patients. Stenting was performed in half of the patients with a mean stent length of 69.6+/-50.3 mm. An average number of 1.24+/-0.55 stents was used for each lesion. During a mean follow-up of 18 months (range 4 to 42), there were 4 deaths, 3 MIs, 13 repeated percutaneous peripheral interventions due to restenosis in previously treated peripheral lesions, two urgent coronary interventions, two ischaemic strokes, two TIAs and one amputation. The combined follow--up MACCE end-point occurred in 32% of patients. CONCLUSIONS: Patients with concomitant CAD and PAD could safely undergo percutaneous cardiovascular and peripheral interventions. Multilevel intervention is associated with a promising long-term follow-up.  相似文献   
67.
This study examined left ventricular (LV) filling properties and exercise hemodynamics noninvasively before and after an exercise training program in patients with chronic heart failure (HF). Although exercise training did not improve LV filling properties in patients with advanced HF, LV filling properties determined the hemodynamic benefit attainable from exercise in this patient group.  相似文献   
68.
69.
70.

Purpose

The prenatal assessment of lung volume is becoming increasingly important in determining survival in both preterm infants and newborns affected by pulmonary hypoplasia. This study aimed to examine the lung volumes in the human fetus at varying gestational ages.

Materials and methods

Using anatomical, hydrostatic (water displacement according to Archimedes’ patent) and statistical methods (one-way ANOVA test for paired data and post-hoc Bonferroni test, Kolmogorov–Smirnov test, Levene’s test, Student’s t test, regression analysis), volumes of the right and left lungs were measured in 67 human fetuses of both sexes (35 males, 32 females) aged 16–25 weeks, derived from spontaneous abortions and stillbirths.

Results

No male–female differences concerning the right and left pulmonary volumes were found. The mean volume of the right lung increased from 1.43 ± 0.25 to 8.45 ± 2.66 cm3, according to the cubic function y = –1.592 + 0.0007 × age3 ± 0.851 (R 2 = 0.84). The volumetric growth of the left lung, from 1.24 ± 0.22 to 6.78 ± 3.03 cm3, followed the cubic model y = –1.110 + 0.0005 × age3 ± 0.794 (R 2 = 0.78). The total pulmonary volume increased from 2.67 ± 0.47 to 15.22 ± 5.58 cm3, in accordance with the cubic model y = –2.729 + 0.0012 × age3 ± 1.598 (R 2 = 0.83). The mean volumes of the right and left lungs accounted for 54.9 ± 2.0 and 45.1 ± 2.0 %, respectively, of the total lung volume.

Conclusions

No sex differences are found between the lung volumes in the fetus. The growth of fetal lung volume follows a three-degree polynomial function. Throughout the analyzed period the two lungs grow proportionately to each other, with the volumetric predominance of the right lung. The lung volumes in the fetus are of great relevance in the evaluation of the normal pulmonary growth and the diagnosis of pulmonary hypoplasia.  相似文献   
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