全文获取类型
收费全文 | 1911篇 |
免费 | 136篇 |
国内免费 | 8篇 |
专业分类
耳鼻咽喉 | 14篇 |
儿科学 | 34篇 |
妇产科学 | 24篇 |
基础医学 | 251篇 |
口腔科学 | 33篇 |
临床医学 | 149篇 |
内科学 | 463篇 |
皮肤病学 | 31篇 |
神经病学 | 190篇 |
特种医学 | 50篇 |
外国民族医学 | 1篇 |
外科学 | 397篇 |
综合类 | 9篇 |
一般理论 | 1篇 |
预防医学 | 103篇 |
眼科学 | 45篇 |
药学 | 105篇 |
中国医学 | 2篇 |
肿瘤学 | 153篇 |
出版年
2023年 | 15篇 |
2021年 | 45篇 |
2020年 | 31篇 |
2019年 | 33篇 |
2018年 | 54篇 |
2017年 | 40篇 |
2016年 | 36篇 |
2015年 | 38篇 |
2014年 | 56篇 |
2013年 | 87篇 |
2012年 | 119篇 |
2011年 | 124篇 |
2010年 | 56篇 |
2009年 | 50篇 |
2008年 | 85篇 |
2007年 | 77篇 |
2006年 | 114篇 |
2005年 | 107篇 |
2004年 | 69篇 |
2003年 | 75篇 |
2002年 | 48篇 |
2001年 | 47篇 |
2000年 | 55篇 |
1999年 | 56篇 |
1998年 | 25篇 |
1997年 | 29篇 |
1996年 | 20篇 |
1995年 | 22篇 |
1994年 | 15篇 |
1993年 | 8篇 |
1992年 | 45篇 |
1991年 | 24篇 |
1990年 | 19篇 |
1989年 | 33篇 |
1988年 | 22篇 |
1987年 | 28篇 |
1986年 | 32篇 |
1985年 | 18篇 |
1984年 | 17篇 |
1983年 | 16篇 |
1982年 | 13篇 |
1980年 | 11篇 |
1979年 | 21篇 |
1978年 | 10篇 |
1976年 | 9篇 |
1974年 | 8篇 |
1973年 | 13篇 |
1972年 | 9篇 |
1969年 | 14篇 |
1967年 | 15篇 |
排序方式: 共有2055条查询结果,搜索用时 15 毫秒
1.
2.
3.
Marilyn Hravnak Leslie A Hoffman Melissa I Saul Thomas G Zullo Julie F Cuneo Ronald V Pellegrini 《American journal of critical care》2004,13(6):499-507; discussion 508
BACKGROUND: Studies suggest that patients who undergo off-pump coronary artery bypass grafting (OPCABG) have fewer short-term complications and use fewer inpatient resources than do patients who undergo standard coronary artery bypass grafting (CABG) with extracorporeal circulation. However, dissimilarity between groups in risk factors for complications has hindered interpretation of results. OBJECTIVES: To compare the prevalence of selected complications (atrial fibrillation, stroke, reoperation, and bleeding) and inpatient resource utilization (length of stay, discharge disposition, total charges) between subjects undergoing primary isolated CABG or OPCABG who were matched with respect to key risk factors. METHODS: Retrospective, causal-comparative survey conducted in 1 center for 18 months. Patients who underwent primary isolated CABG or OPCABG were matched for sex, age (within 2 years), left ventricular ejection fraction (within 0.05), and graft-patient ratio (exact match) and compared for prevalence of new-onset atrial fibrillation, stroke, reoperation within 24 hours, and bleeding. Statistical analysis included Wilcoxon and t tests for paired comparisons. RESULTS: The sample (107 matched pairs) was 63% male, with a mean age of 66 (SD 9.5) years, a mean left ventricular ejection fraction of 0.51 (SD 0.13), and a mean graft-patient ratio of 3.41 (SD 0.74). The 2 groups did not differ significantly in New York Heart Association class (P = .43), Acute Physiology and Chronic Health Evaluation III score (P = .22), postoperative beta-blocker use (P = .73), or comorbid conditions. None of the complications examined differed significantly between pairs. CONCLUSION: Patients with comparable risk profiles have similar prevalences of selected complications after CABG and OPCABG. 相似文献
4.
Arnold Criel Gregor Verhoef Robert Vlietinck Cristina Mecucci Johan Billiet Lucienne Michaux Peter Meeus ries Louwagie Angeline Van Orshoven Achiel Van Hoof Mark Boogaerts Herman Van den Berghe & Chris De Wolf-Peeters 《British journal of haematology》1997,97(2):383-391
We analysed a group of 390 patients, diagnosed with chronic lymphocytic leukaemia (CLL). Cases were subclassified as morphologically typical and atypical CLL according to the criteria of the FAB proposal. Typical CLL cases were mostly diagnosed at a low-risk stage (Binet A/Rai 0), required no immediate treatment and expected a long survival; atypical CLL cases mostly presented at a more advanced risk stage (Binet B/Rai I–II), usually required immediate treatment and their survival was shorter. Moreover, clinical staging was of prognostic significance in typical but not in atypical cases. In typical CLL, del(11q) was the most common chromosomal abnormality (21%) whereas in atypical CLL trisomy 12 was found in about 65% of the cases documented with an abnormal karyotype. Although chromosomal abnormalities were associated with a poor survival in typical CLL, they are of no prognostic significance in atypical CLL. Based on these data, we conclude that subtyping CLL by morphology enables the identification of two groups of cases, each characterized by a specific clinical presentation, different cytogenetic abnormalities and prognostic parameters. We speculate that these two groups may represent two related, but different, diseases with different prognostic parameters and a different survival. 相似文献
5.
A Montanara R Pani R Pellegrini N S Polli S Soluri 《The British journal of radiology》1986,59(708):1171-1173
This paper describes research into measurement and reduction of the radiation dose to the lens during various examinations, namely skull and orbit, optic canal and optic strut, superior and inferior orbital fissure, localisation of foreign bodies in the eye, calcifications, orbital fractures, macrodacryography and orbital venography. Using rare-earth screens and high-sensitivity films, without an antiscattering grid, and with an added filtration of 0.5 mm Cu, it is possible to reduce the radiological risk during all investigations involving skull, orbit and eyeballs, while maintaining a good image quality. Particularly in those examinations with direct magnification (macrodacryography and venography, foreign bodies in the eye, orbital fractures), the dose to the lens is very low: less than 0.2 mGy/radiograph. 相似文献
6.
V. Pellegrini S. Ohno S. Hirose H. Matsuda Y. Hiraga 《The British journal of ophthalmology》1986,70(6):474-477
A 49-year-old Japanese man presented with chronic granulomatous uveitis in his left eye. Later he developed macular subretinal neovascularisation. The chest x-ray showed bilateral hilar lymphadenopathy. Bronchoscopy and gallium-67 scanning were positive, PPD skin test negative, and serum angiotensin converting enzyme (ACE) levels increased. Ophthalmoscopy and fluorescein angiography of the left eye showed perivasculitis, retinochoroidal exudates, snow banking, and vitreous opacity. On these findings, the diagnosis of sarcoidosis was made. Treatment was based on topical corticosteroids, mydriatics, beta blockers, and oral carbonic anhydrase inhibitors. After 15 months the visual acuity decreased in the left eye, and a neovascular membrane was observed in the macula. Fluorescein angiography confirmed subretinal neovascularisation. Almost two years later the patient still has the neovascular membrane in his left eye. 相似文献
7.
Bicarbon valve - European multicenter clinical evaluation 总被引:1,自引:0,他引:1
J.B Borman W.G.B Brands L Camilleri M Cotrufo W Daenen I Gandjbakhch C Infantes A Khayat F Laborde A Pellegrini A Piwnica B Reichart R Sharony R Walesby H Warembourg 《European journal of cardio-thoracic surgery》1998,13(6):685-693
Objective: Fifteen collaborating centers in eight countries present their pooled experience with the new Bicarbon™ bileaflet valve. Methods: Between 4/90 and 4/96, 1351 patients, 806 males and 545 females, aged 10 to 83, mean 58.4±12.4, underwent valve implantation. Operations: AVR, 726; MVR, 475; DVR, 150. Additional procedures: CABG, 211; TV repair, 64; other, 152. Results: Mortality: 67 early (seven valve related) and 56 late (40 valve related). Valve thrombosis: six obstructive, three non-obstructive; embolism: nine major cerebral, 37 other. Major bleeding: 29. Hemolysis: two clinically significant. Non-structural dysfunction: 24 paravalvular leaks, one leaflet interference. No structural failure! Endocarditis: 24. Reoperation 48: 22 non-structural dysfunctions, 14 endocarditis, seven thrombosis and embolism, five other. Estimated 5-year freedom from valve-related deaths is 97.2% for AVR and 92.4% for MVR; 4-year freedom from valve related deaths for DVR is 90.5%. Mean calculated NYHA improvement is 1.24. Conclusions: The Bicarbon mechanical prosthesis is well designed, durable, has good hemodynamic features and an acceptably low incidence of complications. 相似文献
8.
Thoracoscopic esophagomyotomy. Initial experience with a new approach for the treatment of achalasia. 总被引:17,自引:0,他引:17 下载免费PDF全文
C Pellegrini L A Wetter M Patti R Leichter G Mussan T Mori G Bernstein L Way 《Annals of surgery》1992,216(3):291-299
The authors treated 17 patients with achalasia by a thoracoscopic (15 patients) or laparoscopic (2 patients) Heller myotomy. All patients had dysphagia and an upper gastrointestinal series demonstrating a dilated esophagus with a bird-beak deformity at the cardia. Manometry showed a mean lower esophageal sphincter (LES) pressure of 32 +/- 4 mmHg, incomplete sphincter relaxation on swallowing, and no primary esophageal peristalsis. After operation, mean LES pressure was 10 +/- 2 mmHg. Fifteen patients were fed on the second postoperative day. The average hospital stay was 3 days, and there were no deaths or major complications. In three early patients, the myotomy was not carried far enough onto the stomach, and dysphagia persisted until a second myotomy was performed (laparoscopically in two patients). The authors found that having an endoscope in the esophagus during the operation facilitated exposure and was vital to determine the appropriate length of the myotomy. With regard to dysphagia, final results were excellent in 12 patients (70%), good in two patients (12%), fair in two patients (12%), and poor in one patient (6%). Heller myotomy can be safely and reliably performed with minimally invasive techniques. Dysphagia is relieved, postoperative pain is minimal, hospital stay is short, and the patient can return quickly to normal activity. 相似文献
9.
Lucienne Mannessier Phillipe Rouger Carol L. Johnson Kathleen A. Mueller and W. Laurence Marsh 《Vox sanguinis》1986,50(4):240-244
A patient with Hodgkin's disease became temporarily Wj-negative with alloanti-Wj in his serum. Four human autoantibodies, and 1 of 2 murine monoclonal antibodies, with serological characteristics of anti-Wj were nonreactive with his red cells, confirming that they have anti-Wj specificity. Six siblings of the patient are all Wj-positive. The patient was also temporarily Anton-negative, and cross-testing between Wj and Anton red cells and antisera showed mutual compatibility, indicating that the antigens are the same. The patient and 3 of his 6 siblings are also of the rare Lu: - 13 phenotype, providing the first evidence that this is an inherited characteristic. 相似文献
10.