全文获取类型
收费全文 | 3329篇 |
免费 | 180篇 |
国内免费 | 20篇 |
专业分类
耳鼻咽喉 | 15篇 |
儿科学 | 48篇 |
妇产科学 | 33篇 |
基础医学 | 455篇 |
口腔科学 | 73篇 |
临床医学 | 304篇 |
内科学 | 606篇 |
皮肤病学 | 41篇 |
神经病学 | 205篇 |
特种医学 | 505篇 |
外科学 | 717篇 |
综合类 | 11篇 |
预防医学 | 109篇 |
眼科学 | 43篇 |
药学 | 130篇 |
中国医学 | 3篇 |
肿瘤学 | 231篇 |
出版年
2024年 | 9篇 |
2023年 | 64篇 |
2022年 | 106篇 |
2021年 | 177篇 |
2020年 | 82篇 |
2019年 | 117篇 |
2018年 | 145篇 |
2017年 | 104篇 |
2016年 | 128篇 |
2015年 | 120篇 |
2014年 | 148篇 |
2013年 | 183篇 |
2012年 | 289篇 |
2011年 | 265篇 |
2010年 | 149篇 |
2009年 | 125篇 |
2008年 | 182篇 |
2007年 | 197篇 |
2006年 | 160篇 |
2005年 | 121篇 |
2004年 | 94篇 |
2003年 | 101篇 |
2002年 | 106篇 |
2001年 | 30篇 |
2000年 | 27篇 |
1999年 | 18篇 |
1998年 | 18篇 |
1997年 | 14篇 |
1996年 | 19篇 |
1995年 | 8篇 |
1994年 | 7篇 |
1993年 | 6篇 |
1992年 | 16篇 |
1991年 | 6篇 |
1990年 | 8篇 |
1989年 | 5篇 |
1988年 | 5篇 |
1987年 | 5篇 |
1981年 | 4篇 |
1980年 | 7篇 |
1979年 | 5篇 |
1978年 | 7篇 |
1977年 | 6篇 |
1974年 | 4篇 |
1971年 | 4篇 |
1931年 | 5篇 |
1928年 | 6篇 |
1927年 | 4篇 |
1923年 | 4篇 |
1893年 | 5篇 |
排序方式: 共有3529条查询结果,搜索用时 15 毫秒
971.
Maximilian Y. Emmert Sacha P. Salzberg Lorenz S. Emmert Sohil Behjati Andre Plass Christian Felix Volkmar Falk Juerg Gruenenfelder 《European journal of heart failure》2009,11(11):1106-1109
Adalimumab belongs to the group of tumour necrosis factor‐α inhibitors and has been approved for the treatment Crohn's Disease since 2007. Herein we report a severe adverse reaction to adalimumab in a 25‐year‐old female patient. One week after the initial‐dose of adalimumab (160 mg), which was initiated due to an acute exacerbation of Crohn's disease, the patient developed a fulminant cardiomyopathy. In severe cardiogenic shock, the patient required an extracorporeal membrane‐oxygenation system for 8 days until cardiac recovery. 相似文献
972.
973.
974.
975.
Pulmonary abnormalities in immunocompromised patients: comparative detection with parallel acquisition MR imaging and thin-section helical CT 总被引:6,自引:0,他引:6
Eibel R Herzog P Dietrich O Rieger CT Ostermann H Reiser MF Schoenberg SO 《Radiology》2006,241(3):880-891
PURPOSE: To compare parallel acquisition magnetic resonance (MR) imaging with thin-section helical computed tomography (CT) for depiction of pulmonary abnormalities suggestive of pneumonia in immunocompromised patients. MATERIALS AND METHODS: The institutional review board approved this study; prior consent was obtained. Thirty consecutive neutropenic patients (10 women, 20 men; mean age, 51 years +/- 15 [standard deviation]; range, 25-75 years) with fever of unknown origin or clinical signs and symptoms of lung infection were examined with breath-hold single-shot half-Fourier turbo spin-echo MR imaging. To reduce image blurring and increase MR signal in the lungs, the echo time was shortened with generalized autocalibrating partially parallel acquisition (GRAPPA). Patients underwent thoracic CT (four detector rows and 1-mm section thickness [4 x 1 mm]; pitch, 6) as reference standard. Pulmonary abnormalities (ill-defined nodules, ground-glass opacity areas, and consolidation), their location and distribution, and lesion characteristics were analyzed at MR imaging by three readers, blinded to results of CT, in consensus. Frequencies were calculated for each feature; paired Wilcoxon rank sum test was used to examine whether differences between CT and MR imaging features were statistically significant (alpha < .05). Bonferroni adjustments were performed. Overall sensitivity, specificity, and positive and negative predictive values were determined. RESULTS: Twenty-two patients had pulmonary abnormalities at CT. In 21 (95%) patients, pneumonia was correctly diagnosed with MR imaging. One false-negative finding occurred in a patient with ill-defined nodules smaller than 1 cm at CT. One false-positive finding with MR imaging was the result of blurring and respiratory artifacts (sensitivity, 95%; specificity, 88%; positive predictive value, 95%; negative predictive value, 88%). There was no significant difference in lesion location and distribution. CONCLUSION: With parallel imaging (GRAPPA technique) and fast MR imaging, detection of pulmonary abnormalities is almost as good as with CT. MR imaging has a slight disadvantage in its lower capability to assist in characterization of specific internal features, such as cavitations. 相似文献
976.
Maximilian A Pichlmaier Omke E Teebken Nawid Khaladj Jürgen Weidemann Michael Galanski Axel Haverich 《European journal of cardio-thoracic surgery》2008,34(3):600-604
Objective: The frozen elephant trunk technique allows the repair of concomitant aortic arch and proximal descending aortic pathology in a single stage by using a hybrid prosthesis consisting of a vascular graft with a distal stented end. There are patients, however, who will require a second distal operation despite this new technique due to progression of their aortic disease. It has been unclear whether the presence of the stented segment of the hybrid prosthesis results in unexpected technical difficulties or possibly advantages for further vascular reconstruction. Methods: Six patients out of our initial cohort of 39 treated with a hybrid prosthesis from 2001 through 2006 have since required an additional distal aortic reconstruction. Two received endoluminal stent grafts, four had extensive open replacements. Results: There was no 30-day mortality, one patient died on day 133 having been discharged from hospital of an unrelated MRSA septicaemia. Complete thrombosis of the proximally covered aneurysm or the false lumen had occurred in all patients so that the replacements reached from the end of the stented portion of the hybrid prosthesis to the desired distal level. The operative approach proved to be facilitated by the hybrid prosthesis in terms of the necessary exposure and operative trauma. Postoperative recovery was uneventful as related to the hybrid prosthesis with few pulmonary complications and at least comparable to contemporary results for second stage elephant trunk procedures. Conclusions: The distal operative replacement of the aorta following a frozen elephant operation is safe and technically feasible. Early experience suggests that there is an advantage as compared to the conventional elephant technique in terms of intraoperative handling and postoperative recovery. 相似文献
977.
Athanasios K. Petridis Hanna Wedderkopp Hans Hermann Hugo Hubertus Maximilian Mehdorn 《Acta neurochirurgica》2009,151(6):601-604
Objective
Polysialic acid (PSA) is a carbohydrate binding on the neural cell adhesion molecule NCAM and impedes cell-cell interactions. It prevents neural progenitor cell differentiation and promotes their migration. Highly malignant tumours like small cell lung carcinoma (SCLC) also overexpress PSA and this correlates with a negative prognosis. 相似文献978.
979.
980.