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41.
A relative deficit in antioxidant reserve may contribute in cardiac failure   总被引:3,自引:0,他引:3  
Antioxidant enzyme activities, including superoxide dismutase, glutathione peroxidase and catalase, are known to be altered under various physiological and pathophysiological conditions. There is a significant increase in some of these activities in the myocardium during stable hyperfunctional heart hypertrophy subsequent to pressure overload, as well as after exercise training in rats. Hearts with increased antioxidant capacity have been reported to be more resistant to in vivo and in vitro oxidative stress. On the other hand, cardiomyopathy and heart failure under a variety of conditions are accompanied by increased free radicals and lipid peroxidation. These data lead to the hypothesis that maintained or improved function during compensated heart hypertrophy may be supported by an increased antioxidant capacity, and a relative deficit in this 'antioxidant reserve' may contribute in the decompensated state.  相似文献   
42.
Patients with primary sclerosing cholangitis (PSC) have frequent episodes of cholangitis with potential for high mortality while waiting for liver transplantation. However, data on wait‐list mortality specific to liver disease etiology are limited. Using United Network for Organ Sharing (UNOS) database (2002–2013), of 81 592 listed patients, 11 284 (13.8%) died while waiting for transplant. Primary biliary cirrhosis (PBC) patients (N = 3491) compared to PSC (N = 4905) differed with age (56 vs. 47 years), female gender (88% vs. 33%), black race (6% vs. 13%), and BMI (25 vs. 27), P < 0.0001 for all. A total of 993 (11.8%) patients died while waiting for the transplant list. Using competing risk analysis controlling for baseline recipient factors and accounting for receipt of liver transplantation (LT), PBC compared to patients with PSC had higher overall and 3‐month wait‐list mortality (21.6% vs. 12.7% and 5.0% vs. 2.9%, respectively, Gray's test P < 0.001), [1.25 (1.07–1.47)]. Repeat analysis including all etiologies showed higher wait‐list mortality for PBC compared to most etiologies, except for patients listed for diagnosis of alcoholic liver disease (ALD) + hepatitis C virus (HCV). Patients with PBC have high mortality while waiting for liver transplantation. These novel findings suggest that patients with PBC listed for LT may be considered for model for end‐stage disease (MELD) exception points.  相似文献   
43.
44.

Introduction

Distant metastases to liver and lung are not uncommon in colorectal cancer. Resection of metastases is accepted widely as the standard of care. However, there is no firm evidence base for this. This questionnaire survey was carried out to assess the current practice preferences of cardiothoracic surgeons in Great Britain and Ireland.

Methods

An online questionnaire survey was emailed to cardiothoracic surgeons in Great Britain and Ireland. The survey was live for 12 weeks. Responses were collated with SurveyMonkey®.

Results

Overall, there were 75 respondents. The majority (83%) indicated thoracic surgery as a specialist interest. Almost all (99%) used thoracic computed tomography (CT) for staging; 70% added liver CT and 51% added pelvic CT. Fluorodeoxyglucose positron emission tomography was used by 86%. The most frequent indication for pulmonary resection (97%) was solitary lung metastasis without extrathoracic disease. Video assisted thoracoscopic surgery (VATS) was used by 85%. In addition, thoracotomy was used by 96%. A third (33%) used radiofrequency ablation. Synchronous liver and lung resection was contraindicated for 83% of respondents. Over three-quarters (77%) thought that scientific equipoise exists presently for lung resection for colorectal lung metastases but only 21% supported a moratorium on this type of surgery until further evidence becomes available.

Conclusions

The results confirm that the majority of respondents use conventional cross-sectional imaging and either VATS or formal thoracotomy for resection. The results emphasise the continuing need for formal randomised trials to provide evidence of any survival benefit from pulmonary metastasectomy for colorectal lung metastases.  相似文献   
45.
46.
BACKGROUND AND PURPOSE: The treatment options available for managing bladder calculi include transurethral cystolithotripsy, open cystolithotomy, and shockwave lithotripsy. For larger calculi, transurethral treatment can be time consuming, and the manipulation has the potential to cause urethral injury. Percutaneous suprapubic cystolithotripsy represents another treatment option for bladder calculi which is effective and minimally invasive. PATIENTS AND METHODS: Fifteen patients had bladder calculi treated with percutaneous cystolithotripsy over a 3-year period. The mean stone size was 39 mm (range 10-64 mm). Stones were single in seven patients and multiple in eight patients. The indications for cystolithotripsy were stone size >3 cm, multiple stones >1 cm, and inability to perform transurethral cystolithotripsy because of patient anatomy. Percutaneous suprapubic cystolithotripsy was done through either a 30F or a 36F cystotomy tract. Fragmentation and removal was performed with a 26F rigid nephroscope and the pneumatic Swiss Lithoclast. Suprapubic and urethral catheters were placed postoperatively in all patients. RESULTS: Each patient was cleared of the stone burden with a single procedure, and there were no major complications. The mean duration of suprapubic catheterization was 2.6 (range 1-5) days. CONCLUSION: Percutaneous suprapubic cystolithotripsy is an effective and safe technique for treating large bladder calculi. It is minimally invasive, avoids urethral injury, and, in combination with the pneumatic Swiss Lithoclast, can be used to fragment and remove large and hard bladder calculi.  相似文献   
47.
Mark AK  高立  杨敏洁 《放射学实践》2006,21(12):1292-1295
青年学者常常在完成资料收集和分析之后对获得的结果充满了激情。然而,在开始写作论文时,这种热情常常锐减。事实也如此,国家级学术会议的论文数远高于最终发表的医学文献数。优秀的研究成果不能发表的原因2大多在于写作新手在开始写作时对写作的认识混乱和畏缩。一般产生畏缩的原因有2个:要么是研究者不知从何着手,要么是不知如何组织文章结构。不过,大部分放射学论文的写作均有规律可寻,在很大程度上是程式化的。本文试图介绍一种可应用于典型放射学论文的逐段写作法。如果初学者能够完成按照本文教授的18段写作,其论文将具有合理的结构,…  相似文献   
48.
INTRODUCTION: Head and neck squamous cell carcinoma (HNSCC) is a devastating and deadly disease, largely because it is diagnosed in late stage. Cure rates, currently at 50%, could increase to >80% with early detection. In this study, we evaluate soluble CD44 (solCD44) as an early detection tool for HNSCC by determining whether it reliably distinguishes HNSCC from benign disease of the upper aerodigestive tract. METHODS: We carried out the solCD44 ELISA on oral rinses from 102 patients with HNSCC and 69 control patients with benign diseases of upper aerodigestive tract to determine the sensitivity and specificity of the test for differentiating HNSCC from benign disease. Furthermore, we did a pilot study using methylation-specific PCR primers on oral rinses from 11 HNSCC patients with low solCD44 levels and 10 benign disease controls. RESULTS: Mean salivary solCD44 levels were 24.4 +/- 32.0 ng/mL for HNSCC patients (range, 0.99-201 ng/mL) and 9.9 +/- 16.1 ng/mL (range, 0.73-124 ng/mL) for the patients with benign disease (P < 0.0001). Depending on cutoff point and HNSCC site, sensitivity ranged from 62% to 70% and specificity ranged from 75% to 88%. Nine of 11 HNSCC and 0 of 10 controls with low solCD44 levels showed hypermethylation of the CD44 promoter. CONCLUSIONS: SolCD44 is elevated in the majority of HNSCC and distinguishes cancer from benign disease with high specificity. Whereas the solCD44 test lacks sensitivity by itself, methylation status of the CD44 gene seems to complement the solCD44 test. Our pilot data indicate that, together, these markers will detect HNSCC with very high sensitivity and specificity.  相似文献   
49.
Topical antibacterials are being widely used for the treatment or prevention of superficial bacterial infections. Emergence of drug resistant mutant strains of microorganisms and development of irritant and allergic contact dermatitis is a common problem with many of the topical antibacterials. Topical antibacterials are being reviewed with special emphasis on their spectrum of activity, resistance patterns, contact sensitivity potential and clinical uses. Factors which help the physician to choose a particular antibacterial for the specific indication in order to have the maximum efficacy and minimum adverse effects are discussed.  相似文献   
50.
A 35- year-old deaf and dumb woman with clinical and histopathological diagnosis of dermatitis herpetiforrnis (DH) is reported for its rare association with rheumatoid arthritis (PA).  相似文献   
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