全文获取类型
收费全文 | 1054篇 |
免费 | 52篇 |
国内免费 | 9篇 |
专业分类
耳鼻咽喉 | 4篇 |
儿科学 | 35篇 |
妇产科学 | 7篇 |
基础医学 | 91篇 |
口腔科学 | 36篇 |
临床医学 | 92篇 |
内科学 | 277篇 |
皮肤病学 | 12篇 |
神经病学 | 49篇 |
特种医学 | 251篇 |
外科学 | 108篇 |
综合类 | 17篇 |
预防医学 | 31篇 |
眼科学 | 17篇 |
药学 | 27篇 |
肿瘤学 | 61篇 |
出版年
2022年 | 4篇 |
2021年 | 7篇 |
2020年 | 11篇 |
2019年 | 5篇 |
2018年 | 10篇 |
2017年 | 10篇 |
2016年 | 10篇 |
2015年 | 19篇 |
2014年 | 30篇 |
2013年 | 25篇 |
2012年 | 29篇 |
2011年 | 36篇 |
2010年 | 37篇 |
2009年 | 34篇 |
2008年 | 22篇 |
2007年 | 39篇 |
2006年 | 37篇 |
2005年 | 32篇 |
2004年 | 34篇 |
2003年 | 18篇 |
2002年 | 22篇 |
2001年 | 22篇 |
2000年 | 16篇 |
1999年 | 13篇 |
1998年 | 48篇 |
1997年 | 59篇 |
1996年 | 55篇 |
1995年 | 49篇 |
1994年 | 48篇 |
1993年 | 32篇 |
1992年 | 15篇 |
1991年 | 19篇 |
1990年 | 17篇 |
1989年 | 21篇 |
1988年 | 31篇 |
1987年 | 13篇 |
1986年 | 29篇 |
1985年 | 26篇 |
1984年 | 12篇 |
1983年 | 18篇 |
1982年 | 18篇 |
1981年 | 10篇 |
1980年 | 10篇 |
1978年 | 6篇 |
1977年 | 12篇 |
1976年 | 16篇 |
1975年 | 5篇 |
1971年 | 3篇 |
1969年 | 3篇 |
1968年 | 3篇 |
排序方式: 共有1115条查询结果,搜索用时 15 毫秒
1.
Comparative safety study on severe anemia by simeprevir versus telaprevir‐based triple therapy for chronic hepatitis C
下载免费PDF全文
![点击此处可从《Journal of gastroenterology and hepatology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Eiichi Ogawa Norihiro Furusyo Eiji Kajiwara Hideyuki Nomura Akira Kawano Kazuhiro Takahashi Kazufumi Dohmen Takeaki Satoh Koichi Azuma Makoto Nakamuta Toshimasa Koyanagi Kazuhiro Kotoh Shinji Shimoda Jun Hayashi The Kyushu University Liver Disease Study Group 《Journal of gastroenterology and hepatology》2015,30(8):1309-1316
2.
3.
Intracranial circulation: pulse-sequence considerations in three- dimensional (volume) MR angiography 总被引:2,自引:0,他引:2
The technique and feasibility of magnetic resonance (MR) angiography of intracranial vessels were studied in 35 healthy volunteers. Variations in image orientation, repetition time (TR), and flip angle were evaluated to determine their effects on flow-related enhancement. Gradient modifications--including echo time (TE), motion compensation, bandwidth, and field of view--were also studied in an effort to reduce motion-induced phase shifts. Results indicated that a FISP (fast imaging with steady precession) sequence with a TR of 50 msec, TE of 15 msec, velocity compensation in the read and section-select directions, acceleration compensation in the read direction, anisotropic volume, and a 1.25-mm partition thickness produced three-dimensional angiographic MR images that were accurate and reproducible in the depiction of the major intracranial vessels. Difficulties with field of view, persistent signal void secondary to higher-order motion, and spatial resolution remain major problems requiring additional study. 相似文献
4.
A. Dohmen 《European archives of psychiatry and clinical neuroscience》1940,112(2):284-289
Ohne Zusammenfassung 相似文献
5.
6.
Immunological and echocardiographic evaluation of decellularized versus cryopreserved allografts during the Ross operation. 总被引:3,自引:0,他引:3
Francisco Diniz Affonso da Costa Pascal Maria Dohmen Daniele Duarte Cristina von Glenn Sérgio Veiga Lopes Hermínio Haggi Filho Marise Brenner Affonso da Costa Wolfgang Konertz 《European journal of cardio-thoracic surgery》2005,27(4):572-578
OBJECTIVE: Compare the immunological and echocardiographic data of decellularized versus cryopreserved allografts used for RVOT reconstruction during Ross operation. METHODS: From 16/01/03 thru 07/10/03, 20 Ross operations were performed using decellularized (n=11) or cryopreserved (n=9) allografts. Echocardiography was done at discharge, 1, 3, 6 and 12 months and annually thereafter. Samples for determination of antibodies against HLA class I and II were obtained preoperatively and at days 5, 10, 30, 90 and 180 postoperatively. These samples were tested by the ELISA method in LAT-M dishes (unspecific) for identification of circulating antibodies and the results expressed as mean sample values (Is=DO/cutoff). If positive, LAT-E (specific) was performed and PRA levels determined. RESULTS: There was no mortality. Cryopreserved allografts showed marked Is values elevations for class I and II antibodies which started at the first month and remained elevated up to 6 months. In contrast, of the patients receiving decellularized allografts, seven remained negative, two patients had only marginal elevation of class I antibodies and two patients showed abnormal elevations of PRA levels. This response happened earlier than in the cryopreserved group, starting on the 5th postoperative day and has returned to baseline levels in one case. Echocardiography showed mild, but significant, elevation of gradients in cryopreserved valves but none in the decellularized. CONCLUSIONS: Decellularized allografts had normal function up to 18 months and showed important reduction of the immunogenic response when compared to cryopreserved valves. 相似文献
7.
8.
Ralls PW; Johnson MB; Kanel G; Dobalian DM; Colletti PM; Boswell WD Jr; Radin DR; Halls JM 《Radiology》1986,161(2):451-454
FM sonography - a signal-processing technique that uses frequency and phase information as well as amplitude data - shows promise in evaluation of patients with diffuse liver disease. In a prospective blinded review of 37 patients with biopsy-proved liver disease and 42 healthy volunteers, FM sonography was clearly superior to traditional amplitude-based (AM) sonography in distinguishing healthy from diseased subjects. Statistically significant differences were seen in accuracy (FM, 98.7%; AM, 84.8%), sensitivity (FM, 97.3%; AM, 70.3%), and negative predictive value (FM, 97.7%; AM, 78.8%). Our data also suggest that current FM sonographic techniques cannot differentiate among histologic findings associated with different hepatic parenchymal abnormalities. It is unclear, therefore, whether FM imaging can reduce the numbers of patients who require biopsy for diagnosis or the frequency of biopsy procedures in patients with known disease. 相似文献
9.
Objective . To describe the importance of migraine in Santiago, Chile, by analyzing its prevalence, clinical features and impact by age, gender and socioeconomic status. Methods . In 1993, a representative sample of 1,540 adults of the province of Santiago were interviewed using a standard questionnaire. A total of 1,385 (89.9%) subjects responded to the survey. Initially, a designated member of each household responded to the questionnaire. Subsequently, each household member with headaches was asked to respond to questions about severity, frequency, location, duration, associated symptoms and impact in work and social activities of their most frequent headaches. Migraine diagnoses were determined in accordance with the International Headache Society (IHS) criteria of 1988. Results. Recurrent headaches in the past year were found in 516 (36.82%) respondents, 145 (28.1%) males and 371 (71.9%) females. Total prevalence of migraine was found to be 7.3% (95%, CI 5.9–8.6); 11.9% (95% CI 9.6–14.2) in females and 2.0% (95% CI 0.9–3.0) in males. Overall, migraine constituted 19.6% (101/516) of all headaches reported in this sample. The prevalence did not vary significantly by age groups or socioeconomic status (SES). Migraine with aura had an overall prevalence of 3.5% (CI 0.8–7.1), and was significantly more frequent in females. In 60–70% of cases the attacks lasted 2–6 h and the frequency was 3.3 and 3.4 per month in females and males respectively. Both males and females reported significantly high percentages of attacks during work. Conclusions . Migraine prevalence in a sample of adults of Santiago is similar to that reported in previous studies using IHS criteria. Women of all socioeconomic levels are at an increased risk. 相似文献
10.