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51.
Patients with unstable angina, refractory to intensive medical therapy, are at high risk for developing thrombotic complications, such as recurrent ischemia, myocardial infarction and coronary occlusion during coronary angioplasty. As both platelet aggregation and/or thrombus formation play an important role in this ongoing ischemic process, a monoclonal platelet GPIIb/IIIa receptor antibody (c7E3) or thrombolytic therapy (alteplase) might be able to modify the clinical course and underlying coronary lesion morphology. To evaluate whether alteplase or c7E3 could influence the incidence of complications, we randomized 36 and 60 patients, respectively to alteplase or placebo, or c7E3 or placebo. All patients exhibited dynamic ECG changes and recurrent pain attacks, despite maximal tolerated medical therapy. Patients were randomized in both studies after initial angiography had demonstrated a culprit lesion amenable for angioplasty. After study drug infusion quantitative angiography was repeated and angioplasty performed. Recurrent ischemia during study drug infusion occured in 5, 6, 9 and 16 patients from the alteplase, placebo, c7E3 and placebo group, respectively. Major events defined as death, myocardial infarction or urgent intervention occurred in 7, 3, 1 and 7 patients, respectively. Two patients died: one in the alteplase group and one in the placebo group from the c7E3 study. The first patient due to retroperitoneal hemorrhage, the second as a result of recurrent infarction. Qualitative angiography showed resolution of clots in the c7E3 group only, while the same group of patients showed in 20% an improvement in TIMI flow grade, without deterioration in any patient from this group. Quantitative angiography showed a significant improvement in percentage diameter stenosis in the c7E3 group, which was not observed in all three other groups, although differences between groups were not significant. Alteplase infusion in patients with refractory unstable angina did not change the clinical course, nor the coronary morphology, c7E3 on the other hand, both improved the clinical course and the coronary lesion morphology and rheology in the same category of patients.  相似文献   
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Aims

At present it is unknown what limits the arterial remodeling process during atherosclerotic plaque formation. In healthy arteries remodeling is regulated by the shear stress induced response by the endothelium. As endothelium at the plaque site is assumed to be dysfunctional, we tested the hypothesis that plaque free wall (PFW) determines vascular remodeling during atherosclerotic plaque build-up.

Methods & results

66 human coronary ROIs (38 patients) were studied at baseline and at 3 years follow up applying intravascular ultrasound (IVUS). From the IVUS images the lumen and external elastic membrane contours were delineated to assess wall thickness (WT), vessel area (VA), Plaque Area (PA) and plaque burden (PA/VA*100%). WT < 0.5 mm was defined as normal and determined the arc of the PFW (0–360°). Positive remodeling was defined as relative difference of VA over time >5%. At baseline, IVUS-PFW was inversely related to plaque burden (p < 0.05). Positive remodeling was most frequently observed in ROIs with IVUS-PFW > 180° (i.e. larger than half of the circumference) compared to PFW < 180° (55% vs. 12%, p < 0.05). Accordingly, plaques with IVUS-PFW > 180° at baseline had the largest change in VA (1.1 ± 2.1 vs. −0.4 ± 0.6 mm2, p < 0.05) with an odds ratio of 9.2 to develop positive remodeling.

Conclusions

Our serial IVUS data show that IVUS-PFW is a determinant of vascular remodeling. ROIs with PFW > 180 at baseline had the highest probability to undergo positive remodeling.  相似文献   
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Background

Internet-based guided self-help has been successfully used in the general population, but it is unknown whether this method can be effectively used in outpatient clinics for patients waiting for face-to-face psychotherapy for phobias.

Objective

The aim was to assess the clinical effectiveness of Phobias Under Control, an Internet-based intervention based on exposure therapy with weekly guidance.

Methods

We conducted a randomized controlled trial, recruiting 212 outpatients scheduled to receive face-to-face psychotherapy for any type of phobia at an outpatient clinic. Participants suffering from at least 1 DSM-IV or ICD-10 classified phobia (social phobia, agoraphobia with or without panic disorder, and/or specific phobia as ascertained by a telephone interview at baseline) were randomly allocated to either a 5-week Internet-based guided self-help program based on exposure therapy with weekly student support followed by face-to-face psychotherapy (n=105) or a wait-list control group followed by face-to-face psychotherapy (n=107). Primary outcome was the Fear Questionnaire (FQ). Secondary outcomes were the Beck Anxiety Inventory (BAI) and Center of Epidemiological Studies-Depression scale (CES-D). Assessments took place by telephone at baseline (T0) and on the Internet at posttest (T1, self-assessment at 5 weeks after baseline). Missing data at T1 were imputed.

Results

At posttest, analysis of covariance on the intention-to-treat sample showed significant but small effect sizes between intervention and control groups on the FQ (d=0.35, P=.02), CES-D (d=0.34, P=.03), and a nonsignificant effect size on the BAI (d=0.28. P=.05). Although initial acceptance was good, high nonresponse was observed, with 86 of 212 participants (40.5%) lost to follow-up at T1 and only 14 of 105 (13.3%) intervention participants finishing all 5 weeks.

Conclusions

Phobias Under Control is modestly effective in lowering phobic and depressive symptoms in a relatively short period and may be clinically beneficial when implemented in routine outpatient practice.

Trial Registration

Netherlands Trial Register NTR2233; http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=2233 (Archived by WebCite at http://www.webcitation.org/6O2ioOQSs).  相似文献   
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Objectives. This study reports the 10-year outcome of 856 consecutive patients who underwent attempted coronary angioplasty at the Thoraxcenter during the years 1980 to 1985.

Background. Coronary balloon angioplasty was first performed in 1977, and this procedure was introduced into clinical practice at the Thoraxcenter in 1980. Although advances have been made, extending our knowledge of the long-term outcome in terms of survival and major cardiac events remains of interest and a valuable guide in the treatment of patients with coronary artery disease.

Methods. Details of survival, cardiac events, symptoms and medication were retrospectively obtained from the Dutch civil registry, medical records or by letter or telephone or from the patient's physician and entered into a dedicated data base. Patient survival curves were constructed, and factors influencing survival and cardiac events were identified.

Results. The procedural clinical success rate was 82%. Follow-up information was obtained in 837 patients (97.8%). Six hundred forty-one patients (77%) were alive, of whom 334 (53%) were symptom free, and 254 (40%) were taking no antianginal medication. The overall 5- and 10-year survival rates were 90% (95% confidence interval [CI] 87.6% to 92.4%) and 78% (95% CI 75.0% to 81.0%), respectively, and the respective freedom from significant cardiac events (death, myocardial infarction, coronary artery bypass surgery and repeat angioplasty) was 57% (95% CI 53.4% to 60.6%) and 36% (95% CI 32.4% to 39.6%). Factors that were found to adversely influence 10-year survival were age ≥60 years (≥60 years [67%], 50 to 59 years [82%], <50 years [88%]), multivessel disease (multivessel disease [69%], single-vessel disease [82%]), impaired left ventricular function (ejection fraction <50% [57%], ≥50% [80%]) and a history of previous myocardial infarction (previous myocardial infarction [72%], no previous infarction [83%]). These factors were also found to be independent predictors of death during the follow-up period by a multivariate stepwise logistic regression analysis. Other factors tested, with no influence on survival, were gender, procedural success and stability of angina at the time of intervention.

Conclusion. The long-term prognosis of patients after coronary angioplasty is good, particularly in those <60 years old with single-vessel disease and normal left ventricular function. The majority of patients are likely to experience a further cardiac event in the 10 years after their first angioplasty procedure.  相似文献   

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OBJECTIVE: This study was designed to determine whether antisense oligodeoxynucleotides (ODN) directed against the nuclear proto-oncogene c-myc could inhibit restenosis when given by local delivery immediately after coronary stent implantation. BACKGROUND: Failure of conventional pharmacologic therapies to reduce the incidence of coronary restenosis after percutaneous revascularization techniques has prompted interest in the use of agents that target intracellular central regulatory mechanisms. METHODS: Eighty-five patients were randomly assigned to receive either 10 mg of phosphorothioate-modified 15-mer antisense ODN or saline vehicle by intracoronary local delivery after coronary stent implantation. The primary end point was percent neointimal volume obstruction measured by computerized analysis of electrocardiogram-gated intravascular ultrasound (IVUS) at six-month follow-up. Secondary end points included clinical outcome and quantitative coronary angiography analysis. RESULTS: Analysis of follow-up IVUS data was performed on 77 patients. In-stent volume obstruction was similar between groups (44 +/- 16% and 46 +/- 14%, placebo vs. ODN; p = 0.57; 95% confidence interval: -1.13 to 0.85). Minimum luminal diameter increased from 0.84 +/- 0.36 and 0.90 +/- 0.45 (p = 0.55) to 2.70 +/- 0.37 and 2.80 +/- 0.37 (p = 0.28) after stent implantation, which decreased to 1.50 +/- 0.61 and 1.50 +/- 0.53 (p = 0.98) by six months, yielding similar loss indexes (placebo vs. ODN, respectively). There were no differences in angiographic restenosis rates (38.5 and 34.2%; p = 0.81; placebo vs. ODN) or clinical outcome. CONCLUSIONS: Treatment with 10 mg of phosphorothioate-modified ODN directed against c-myc does not reduce neointimal volume obstruction or the angiographic restenosis rate in this patient population.  相似文献   
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OBJECTIVES: This study was designed to prospectively evaluate the diagnostic performance of multislice spiral computed tomography (MSCT) coronary angiography for the detection of significant lesions in all segments of the coronary tree potentially suitable for revascularization. BACKGROUND: Noninvasive MSCT coronary angiography is a promising coronary imaging technique. METHODS: Sixteen-row MSCT coronary angiography was performed in 128 patients (89% men, mean age 58.9 +/- 11.7 years) in sinus rhythm with stable angina pectoris scheduled for conventional coronary angiography. Sixty percent (77 of 128) of patients received pre-scan oral beta-blockers, resulting in a mean heart rate of 57.7 +/- 7.7 beats/min. The diagnostic performance of MSCT for detection of significant lesions (> or =50% diameter reduction) was compared with that of quantitative coronary angiography (QCA). RESULTS: The sensitivity of MSCT for detection of significant lesions was 92% (216 of 234, 95% confidence interval [CI]: 88 to 95). Specificity was 95% (1,092 of 1,150, 95% CI: 93 to 96), positive predictive value 79% (216 of 274, 95% CI: 73 to 88), and negative predictive value 98% (1,092 of 1,110, 95% CI: 97 to 99). Two > or =50% lesions were missed because of motion artifacts and two because of severe coronary calcifications. The rest (78%, 14 of 18) were detected but incorrectly classified as <50% obstructions. All patients with and 86% (18 of 21) of patients without significant lesions on QCA were correctly classified by MSCT. All patients with significant left main disease or total occlusions were correctly identified on MSCT. CONCLUSIONS: Sixteen-row MSCT coronary angiography permits reliable detection of significant obstructive coronary artery disease in patients with stable angina in sinus rhythm.  相似文献   
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