全文获取类型
收费全文 | 160354篇 |
免费 | 10557篇 |
国内免费 | 801篇 |
专业分类
耳鼻咽喉 | 1537篇 |
儿科学 | 4143篇 |
妇产科学 | 2948篇 |
基础医学 | 21569篇 |
口腔科学 | 3698篇 |
临床医学 | 15547篇 |
内科学 | 34305篇 |
皮肤病学 | 2973篇 |
神经病学 | 15443篇 |
特种医学 | 6407篇 |
外国民族医学 | 7篇 |
外科学 | 24089篇 |
综合类 | 2005篇 |
现状与发展 | 2篇 |
一般理论 | 143篇 |
预防医学 | 11567篇 |
眼科学 | 3406篇 |
药学 | 10901篇 |
2篇 | |
中国医学 | 252篇 |
肿瘤学 | 10768篇 |
出版年
2023年 | 842篇 |
2022年 | 1285篇 |
2021年 | 2953篇 |
2020年 | 2037篇 |
2019年 | 2946篇 |
2018年 | 3580篇 |
2017年 | 2781篇 |
2016年 | 3184篇 |
2015年 | 3652篇 |
2014年 | 5228篇 |
2013年 | 7088篇 |
2012年 | 10935篇 |
2011年 | 11545篇 |
2010年 | 6589篇 |
2009年 | 6306篇 |
2008年 | 10585篇 |
2007年 | 11271篇 |
2006年 | 10752篇 |
2005年 | 10974篇 |
2004年 | 10339篇 |
2003年 | 9807篇 |
2002年 | 9262篇 |
2001年 | 1616篇 |
2000年 | 1279篇 |
1999年 | 1729篇 |
1998年 | 2192篇 |
1997年 | 1707篇 |
1996年 | 1484篇 |
1995年 | 1346篇 |
1994年 | 1188篇 |
1993年 | 1159篇 |
1992年 | 865篇 |
1991年 | 874篇 |
1990年 | 694篇 |
1989年 | 685篇 |
1988年 | 645篇 |
1987年 | 652篇 |
1986年 | 604篇 |
1985年 | 622篇 |
1984年 | 704篇 |
1983年 | 641篇 |
1982年 | 810篇 |
1981年 | 765篇 |
1980年 | 656篇 |
1979年 | 444篇 |
1978年 | 416篇 |
1977年 | 444篇 |
1976年 | 375篇 |
1975年 | 321篇 |
1974年 | 301篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
91.
92.
We report our experience using Sarmiento's method for the conservative treatment of 91 consecutive fractures of the lower leg. The mean age of the patients in our series was 34 years. One patient had an open fracture. All of the patients were followed and were evaluated clinically and radiographically 6 to 12 months after injury. After a period of immobilization by traditional methods (traction/long leg cast), the Sarmiento brace was applied at a mean of 42 days, allowing early weightbearing and mobilization. The brace was removed at a mean of 90 days. Clinical results were excellent; there was minimal persistence of knee or ankle limitation; 84% of the patients had less than 5 mm of final shortening; 96% had less than 4 degrees of final angulation. Work was resumed at a mean of 103 days. We had one nonunion, which we treated operatively 6 months after injury by osteosynthesis and autologous bone grafting. All of the patients were asked to complete a questionnaire; 51% responded, with an average followup of 5 years (range, 1 to 10 years). These patients had been able to resume sports activity 8 months after injury; 52% were skiing 1 year after injury, and 96% were satisfied with the treatment method used. One patient complained of persistent pain. 相似文献
93.
94.
95.
Robert C Susil Kevin Camphausen Peter Choyke Elliot R McVeigh Gary S Gustafson Holly Ning Robert W Miller Ergin Atalar C Norman Coleman Cynthia Ménard 《Magnetic resonance in medicine》2004,52(3):683-687
A technique for transperineal high-dose-rate (HDR) prostate brachytherapy and needle biopsy in a standard 1.5 T MRI scanner is demonstrated. In each of eight procedures (in four patients with intermediate to high risk localized prostate cancer), four MRI-guided transperineal prostate biopsies were obtained followed by placement of 14-15 hollow transperineal catheters for HDR brachytherapy. Mean needle-placement accuracy was 2.1 mm, 95% of needle-placement errors were less than 4.0 mm, and the maximum needle-placement error was 4.4 mm. In addition to guiding the placement of biopsy needles and brachytherapy catheters, MR images were also used for brachytherapy treatment planning and optimization. Because 1.5 T MR images are directly acquired during the interventional procedure, dependence on deformable registration is reduced and online image quality is maximized. 相似文献
96.
Thomas Teltzrow Franz-Josef Kramer Andrea Schulze Carola Baethge Peter Brachvogel 《Journal of cranio-maxillo-facial surgery》2005,33(5):307-313
INTRODUCTION: The aim of this study was to review complications in a series of 1264 consecutive patients who were operated in a single centre during a 20-year-period. MATERIAL AND METHODS: Complications were documented, their incidences calculated and compared with data from the literature. RESULTS: In 35 patients (2.8%) infection developed requiring extraoral incision and drainage; in 27 patients (2.1%) the inferior alveolar nerve was inadvertently cut; 18 patients (1.4%) had to undergo re-operation due to bending or fracture of osteosynthesis material; 15 patients (1.2%) suffered from bleeding complications; in 12 patients (0.9%) an unfavourable split occurred. In 8 patients (0.6%) foreign bodies were left in situ; in 7 patients a partial weakness of the facial nerve occurred, which was permanent in 1 patient. Six patients (0.5%) with a significantly higher age than average (mean: 33.6 years in comparison with 23.1 years) developed non-union at the site of osteotomy, and the mandible had to be bone grafted. Two patients (0.2%) developed osteomyelitis, and in one patient airway problems led to a need for tracheostomy (0.1%). CONCLUSION: Although some of these complications of bilateral sagittal split with osteotomy carry severe limitations in health related quality of life, it remains an overall safe procedure, demanding, however, comprehensive informed consent. Good knowledge of technical reasons for these complications should help to reduce their incidence. 相似文献
97.
98.
Benjamin H. S. Lau Sharon K. Riesen Kim P. Truong Esther W. Lau Peter Rohdewald Ray A. Barreta 《The Journal of asthma》2004,41(8):825-832
A randomized, placebo-controlled, double-blind study involving 60 subjects, aged 6-18 years old, was conducted over a period of 3 months to determine the effect of Pycnogenol® (a proprietary mixture of water-soluble bioflavonoids extracted from French maritime pine) on mild-to-moderate asthma. After baseline evaluation, subjects were randomized into two groups to receive either Pycnogenol® or placebo. Subjects were instructed to record their peak expiratory flow with an Assess® Peak Flow Meter each evening. At the same time, symptoms, daily use of rescue inhalers (albuterol), and any changes in oral medications were also recorded. Urine samples were obtained from the subjects at the end of the run-in period, and at 1-, 2-, and 3-month visits. Urinary leukotriene C4/D4/E4 was measured by an enzyme immunoassay. Compared with subjects taking placebo, the group who took Pycnogenol® had significantly more improvement in pulmonary functions and asthma symptoms. The Pycnogenol® group was able to reduce or discontinue their use of rescue inhalers more often than the placebo group. There was also a significant reduction of urinary leukotrienes in the Pycnogenol® group. The results of this study demonstrate the efficacy of Pycnogenol® as an adjunct in the management of mild-to-moderate childhood asthma. 相似文献
99.
Peter L Weissberg 《Journal of nuclear medicine》2004,45(11):1794-1795
100.
Claudia Brogsitter Thomas Grüning Reiner Weise Peter Wielepp Oliver Lindner Reiner K?rfer Wolfgang Burchert 《Journal of nuclear medicine》2005,46(1):19-24
(18)F-FDG PET is an important diagnostic tool for detecting myocardial viability in patients with coronary artery disease. In combination with perfusion scanning, (18)F-FDG PET allows differentiation between reversibly and irreversibly damaged myocardium and selection of patients likely to benefit from revascularization. Viability PET is usually performed in two-dimensional (2D) mode. Taking into account the rising number of three-dimensional (3D)-only scanners, a validation of 3D acquisition is required. METHODS: Twenty-one patients with coronary artery disease referred for (18)F-FDG PET underwent an imaging protocol of nongated 2D (2D-NG) and gated 2D (2D-G) acquisitions for 15 min each, followed by 3D gated acquisitions for 10 min (3D-10) and 5 min (3D-5), using an ECAT Exact HR+ scanner. Results were analyzed using a 20-segment polar map in terms of activity concentration (Bq/mL), viability (50% uptake threshold), regional activity distribution, visual assessment of viability based on a 3-point rating scale, and left ventricular ejection fraction. RESULTS: Activity concentration measured in each segment with 2D-G, 3D-10, and 3D-5 showed a good linear correlation with 2D-NG. Quantitative viability assessment with 3D-5 gave a sensitivity of 84% and a specificity of 98%, compared with 2D-NG. No differences in regional activity distribution and visual viability assessment were found between the various protocols. Left ventricular ejection fractions obtained with 3D-10 and 3D-5 showed a good linear correlation with those measured with 2D-G. CONCLUSION: An ECG-gated 3D imaging protocol gave results comparable to those of 2D acquisition with regard to absolute and regional myocardial activity distribution, left ventricular function, and visual viability assessment. Sensitivity for viability assessment with a 50% uptake threshold was significantly less with 3D, but specificity was maintained. This protocol delivers a clinical performance nearly equivalent to that of 2D acquisition. 相似文献