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BACKGROUND: Dye-directed sentinel node biopsy (SNB) for breast cancer provides accurate staging with low morbidity, but for tumors distant from the axilla, its use has been questioned. HYPOTHESIS: Can preoperative breast lymphoscintigraphy (BL) applied selectively to medial hemisphere tumors predict a subset of patients who may not require surgical staging of the axilla? DESIGN: Prospective cohort study. SETTING: Tertiary, multidisciplinary breast center. PATIENTS: Thirty-two women with breast tumors located in the medial hemisphere (30) or inframammary crease (2). INTERVENTION: Peritumoral injection of 500 microCi of technetium Tc 99m sulfur colloid and biplanar imaging. Nonpalpable lesions were localized with ultrasound or mammography. At the time of definitive breast surgery, isosulfan blue dye-directed SNB was performed. Axillary dissection was performed when the SN contained a tumor or could not be identified. MAIN OUTCOME MEASURES: Regional nodal basins identified by BL; success rate of SNB. RESULTS: Preoperative BL demonstrated axillary drainage in 28 patients (88%); 2 patients (6%) had isolated internal mammary radionuclide uptake, and 2 patients had no nodal uptake. Dye-directed axillary SNB succeeded in 27 (87%) of 31 patients, including both patients with failed BL. Breast lymphoscintigraphy had predicted isolated internal mammary drainage in 2 of 4 patients whose SNs could not be identified. Metastases were found in 5 patients (16%). CONCLUSIONS: Axillary radionuclide uptake predicts but does not augment dye-directed SN identification. In those few patients with isolated internal mammary drainage, BL may obviate the need for surgical staging of the axilla.  相似文献   
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The steps involved in establishing a comprehensive pharmaceutical service in an operating and recovery room complex is described. Objectives of the operating room pharmaceutical satellite were to: (1) improve control of distribution, storage and charging for all drugs, especially Schedule II controlled substances; (2) reduce inventory costs and loss of revenue; (3) improve compliance with the drug formulary; and (4) establish patient-oriented pharmaceutical services. The pharmacy satellite improved inventory control and patient charging, assured continual access to all drugs and appropriate security for controlled substances, and expanded the pharmacy department's clinical, drug information and research activities.  相似文献   
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The aim of this study was to develop a placebo model for bipolar disorder to help optimize clinical trial designs for studies targeting manic episodes in bipolar disorder. A bipolar disease database was built based on individual longitudinal data collected from over 3,000 patients in 11 clinical trials for 5 approved bipolar drugs. An empirical placebo effect model with an exponential decay process plus a linear progression process was developed to quantify the time course of the Young Mania Rating Scale total score based on only placebo data from the database. In order to describe the dropout pattern during the trials, a parametric survival model was developed and the Weibull distribution was identified to be the best distribution to describe the data. Based on the likelihood ratio test, it was found that patients with higher baseline score, slower disease improvement and more rapid disease progression tended to dropout earlier, and the trial features such as trial starting year and trial site were also significant covariates for dropout. A combination of the placebo effect model and the dropout model was applied to simulate new clinical trials through Monte-Carlo simulation. Both the placebo effect model and dropout model described the observed data reasonably well based on various diagnostic plots. The joint placebo response and dropout models can serve as a tool to simulate the most likely level of placebo response with the expected dropout pattern to help design a new clinical trial.  相似文献   
6.

Background

Severe cerebral venous-sinus thrombosis (CVT) is a rare disease, and its clinical course, imaging correlates, as well as long-term prognosis have not yet been investigated systematically.

Methods

Multicenter retrospective study. Inclusion criteria were CVT, Glasgow coma scale ≤9, and treatment in the intensive care unit. Primary outcome was death or dependency, assessed by a modified Rankin Score (mRS) >2 at last follow-up.

Results

114 patients were included. At last follow-up (median 2.5 years), 38 patients (33.3 %) showed no or minor residual symptoms (mRS = 0 or 1), 12 (10.5 %) had a mild (mRS = 2), 13 (11.4 %) a moderate (mRS = 3), 12 (10.5 %) a severe disability (mRS = 4 or 5), and 39 (34.2 %) had died. In bivariate analysis, predictors of poor outcome were any signs of mass effect on imaging, clinical deterioration after admission, and age. In contrast, clinical symptoms on admission and parenchymal lesions per se, such as edema, infarction, or hemorrhage were not predictive. Multivariate predictors of poor outcome were an increase in National Institutes of Health Stroke Scale ≥3 after admission [odds ratio (OR) 6.7], bilateral motor signs in the further course (OR 9.2), and midline shift (OR 5.1).

Conclusion

The outcome of severe CVT is almost equally divided between severe impairment or death and survival with no or only mild handicap. Specifically, space-occupying mass effect and associated neurologic deterioration seem to determine a poor outcome. Therefore, early detection and treatment of mass effect should be the focus of critical care.
  相似文献   
7.
Objectives. To measure the pressure profiles at different positions of the urethral circumference simultaneously.Methods. Twenty-two women with symptoms of genuine stress incontinence underwent urogynecologic assessment and multichannel urethral pressure profilometry (UPP) at rest with a specially designed 8-channel urethral catheter with radial openings.Results. The distribution pattern of maximum urethral closure pressure (MUCP) and functional urethral length (FUL) values were significantly different (P = 0.004 and P = 0.0004, respectively). Most of the highest MUCP values per patient were found between channels 2 and 4 (P = 0.015); most of the greatest FUL values per patient were found between channels 3 and 4 (P = 0.15).Conclusions. The data of our study substantiate asymmetric radial pressure distribution within the urethra and underline the necessity of cautious interpretation of results of conventional single-channel UPP, which might vary because of transducer orientation.  相似文献   
8.
OBJECTIVE: Standard lung donor criteria have been established on opinions and individual experiences rather than on existing evidence. Since the scarcity of donor organs is one of the major limitations to lung transplantation, extension of donor lung criteria might considerably increase the donor pool. This study therefore evaluates the outcome, achieved with the use of extended donors versus standard donors and aims to redefine lung donor criteria. METHODS: We performed a retrospective analysis of 98 consecutive primary lung transplantations from 94 donors from 1/2001 to 12/2002. Donors were classified as extended if they fulfilled at least one criteria: age >55 years, PaO(2) at FiO(2)/PEEP 5 <300mmHg, tobacco history >20 pack years, inhalative drug abuse, presence of infiltration on chest X-ray or purulent secretions at bronchoscopy. Recipients were stratified in two groups according to whether they received a 'standard' or 'extended' organ. Postoperative complications, extubation time, ICU and hospital stay and survival were compared. RESULTS: Twenty-three (24.5%) donors were extended. Twenty-six recipients (26.55%) received organs from extended donors. Differences in intubation times (12+/-2 days standard vs. 14+/-5 days extended, P=0.70), ICU stay (16+/-2 days standard vs. 18+/-5 days extended, P=0.74) and hospital stay (38+/-4 days standard vs. 40+/-6 days extended, P=0.71) were not statistically significant. Postoperative bleeding rates were comparable (n=14 standard vs. n=3 extended) as well as bronchial anastomotic complications (n=7 standard vs. n=3 extended). Three months survival was 88.89% in the standard group vs. 92.31% in the extended group. One year survival is comparable as well with 81.94 vs. 84.62%, respectively. CONCLUSIONS: The use of lung donors who fail to meet standard criteria does not impair short and medium term results compared to standard lung donors. The impact on long term development of BOS has yet to be evaluated. The strict application of standard lung donor criteria excludes a considerable number of lungs potentially suitable for transplantation, thus liberalisation of donor criteria might help to overcome donor shortage.  相似文献   
9.
The risks of thromboembolism following operative treatment of ankle fractures are deep vein thrombosis (DVT) and pulmonary embolism (PE). These are potentially life-threatening complications. Many orthopedic surgeons fail to appreciate the potential complications of thromboembolic events because of their rare and delayed occurrence in foot and ankle operations. The purpose of this report is to describe the potential for DVT and PE following ankle operations. We present three cases in which patients who underwent operative treatment of ankle fractures subsequently developed PE. We also review the literature on the prevalence of thrombosis, risk factors, methods of prophylaxis, and use of prophylaxis in surgical procedures of the lower extremity.  相似文献   
10.
RATIONALE AND OBJECTIVES: To optimize the intraluminal signal intensity of a nitinol stent by performing contrast-enhanced three-dimensional magnetic resonance angiography (CE-MRA) with varying flip angles (FAs). METHODS: Contrast-enhanced magnetic resonance angiography at 1.5 T and FAs of 30 degrees, 100 degrees, and 150 degrees was performed on five sheep with 10 iliac nitinol stents (Memotherm-FLEXX). Maximum-intensity projections (MIPs) and composite images of MIPs were performed and compared. RESULTS: Reconstructed MIPs at an FA of 150 degrees showed a slightly disturbed lumen visibility inside the stent accompanied by low-grade lumen visibility outside the stent and vice versa for an FA of 30 degrees. Composite images of a 30 degrees MIP added to a 150 degrees MIP resulted in improved image quality compared with the standard MIP of a single FA. CONCLUSIONS: Signal loss due to radiofrequency shielding inside nitinol stents imaged by CE-MRA can be reduced by applying high FAs. Composite MIP images allow simultaneous visualization of the lumen inside as well as outside the stent.  相似文献   
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