全文获取类型
收费全文 | 1132129篇 |
免费 | 87298篇 |
国内免费 | 2232篇 |
专业分类
耳鼻咽喉 | 16670篇 |
儿科学 | 34216篇 |
妇产科学 | 34481篇 |
基础医学 | 165310篇 |
口腔科学 | 32601篇 |
临床医学 | 97769篇 |
内科学 | 215252篇 |
皮肤病学 | 22925篇 |
神经病学 | 89041篇 |
特种医学 | 45548篇 |
外国民族医学 | 213篇 |
外科学 | 178551篇 |
综合类 | 31417篇 |
现状与发展 | 3篇 |
一般理论 | 421篇 |
预防医学 | 85485篇 |
眼科学 | 26940篇 |
药学 | 84086篇 |
中国医学 | 2322篇 |
肿瘤学 | 58408篇 |
出版年
2018年 | 10726篇 |
2015年 | 10953篇 |
2014年 | 15316篇 |
2013年 | 23541篇 |
2012年 | 31181篇 |
2011年 | 32714篇 |
2010年 | 19650篇 |
2009年 | 18240篇 |
2008年 | 30663篇 |
2007年 | 33523篇 |
2006年 | 33130篇 |
2005年 | 32516篇 |
2004年 | 31740篇 |
2003年 | 30496篇 |
2002年 | 29247篇 |
2001年 | 47739篇 |
2000年 | 48698篇 |
1999年 | 41207篇 |
1998年 | 12031篇 |
1997年 | 11142篇 |
1996年 | 10865篇 |
1995年 | 10302篇 |
1994年 | 9837篇 |
1992年 | 34095篇 |
1991年 | 33771篇 |
1990年 | 33091篇 |
1989年 | 32028篇 |
1988年 | 29878篇 |
1987年 | 29244篇 |
1986年 | 27831篇 |
1985年 | 27029篇 |
1984年 | 20699篇 |
1983年 | 17734篇 |
1982年 | 11093篇 |
1981年 | 10088篇 |
1980年 | 9481篇 |
1979年 | 20699篇 |
1978年 | 15015篇 |
1977年 | 12669篇 |
1976年 | 11600篇 |
1975年 | 12741篇 |
1974年 | 15684篇 |
1973年 | 15205篇 |
1972年 | 14380篇 |
1971年 | 13392篇 |
1970年 | 12804篇 |
1969年 | 12228篇 |
1968年 | 11200篇 |
1967年 | 10367篇 |
1966年 | 9660篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
Lesions typical of subacute cutaneous lupus erythematosus developed in an elderly woman after 6 months of PUVA (8-methoxypsoralen and longwave ultraviolet light) therapy for psoriasis. Pancytopenia, antibodies to double-stranded DNA, and hypocomplementemia developed concurrently with the appearance of the cutaneous lesions. With discontinuation of photochemotherapy, the cutaneous lesions disappeared and the pancytopenia improved. 相似文献
992.
C4 concentrations and C4 deficiency alleles in systemic lupus erythematosus. 总被引:1,自引:0,他引:1
下载免费PDF全文
![点击此处可从《Annals of the rheumatic diseases》网站下载免费的PDF全文](/ch/ext_images/free.gif)
In a study of 66 patients with systemic lupus erythematosus (SLE) and 80 controls it was found that the presence of two deficiency (null) alleles of C4 had a significant effect on mean C4 concentrations in serum. In six controls who each had two C4 null alleles the mean C4 concentration in serum was 56% lower than in 43 controls without C4 null alleles; the nadir of the C4 concentration in four patients with SLE with two null alleles was also lower by a mean of 55% than in 32 patients who did not have null alleles. Reduced production of C4 allotypes in subjects with two null alleles may be an important determinant of total C4 concentration in patients with SLE. For optimal interpretation of C4 concentrations in SLE, C4 allotyping appears to be indicated, particularly to identify patients who have two null alleles of C4. 相似文献
993.
994.
T W Findley M G Stineman 《American journal of physical medicine & rehabilitation / Association of Academic Physiatrists》1989,68(5):240-251
The process of data entry and initial analysis to locate data errors is described. Basic terms are defined and a simple method of entering data by using word processing software is illustrated. Data checking is done by using visual check of the raw data. Statistical programs are then used to locate possible data errors by finding data points (outliers) that are very different from the average. Special graphic output of statistical programs, scatterplots and box and whisker plots can be used to further locate questionable data. Examples of data entry forms and annotated step by step data cleaning with the use of inexpensive programs for personal computers are presented. 相似文献
995.
A Goldfarb J Weinreb W G Daniel I Kronzon 《Journal of the American Society of Echocardiography》1989,2(5):350-353
A patient who had right and left atrial membranes was examined. The diagnosis and the hemodynamic significance of both membranes were detailed by transesophageal echocardiography and were confirmed by magnetic resonance imaging. Transesophageal imaging was found to be superior to routine echocardiography in visualization of these atrial structures. 相似文献
996.
Prospective randomized comparison of mezlocillin therapy alone with combined ampicillin and gentamicin therapy for patients with cholangitis 总被引:3,自引:0,他引:3
W B Gerecht N K Henry W W Hoffman S M Muller N F LaRusso J E Rosenblatt W R Wilson 《Archives of internal medicine》1989,149(6):1279-1284
Forty-six patients with cholangitis were randomized to receive therapy with mezlocillin sodium (24 patients) or a combination of ampicillin sodium--gentamicin sulfate (22 patients). The biliary concentration of mezlocillin was 112 times higher than that of ampicillin and 778 times higher than that of gentamicin. The ratio of the concentration in serum or bile over the minimum inhibitory concentration against aerobic gram-negative bacilli (therapeutic index) was higher for mezlocillin than for either ampicillin or gentamicin. Twenty (83%) of 24 patients were cured following mezlocillin therapy compared with 9 (41%) of 22 patients after ampicillin-gentamicin therapy. The 3 patients with superinfection were in the ampicillin-gentamicin arm of the study. Fewer toxic or adverse effects occurred in association with mezlocillin treatment than with ampicillin-gentamicin treatment. Mezlocillin therapy was more effective, less toxic, and less expensive than treatment with ampicillin and gentamicin for patients with cholangitis. 相似文献
997.
In the first 100 patients operated on for C T-E PH, three were referred with the diagnosis of UPAA having been made elsewhere. We found that many features of these two conditions are so similar that differential diagnosis is very difficult. Shared features may include findings on chest x-ray film, pulmonary angiography, CT scan and MRI studies. Since the two conditions vary substantially with respect to the methods of potential surgical correction, recognition of this possible differential diagnostic dilemma is important. 相似文献
998.
999.
Preclinical and clinical investigations currently underway are employing novel strategies for combining vaccines with conventional and experimental anticancer therapies. To date, the FDA has not approved a therapeutic cancer vaccine. However, the results of recent investigations suggest an increasing role for vaccines in new models of combination therapy for many types of cancer. This article reviews and discusses therapeutic cancer strategies that employ vaccines in combination with local radiation, chemotherapy, hormone therapy, and anti-CTLA-4 mAb. Preclinical studies have shown that certain anticancer agents have immune modulatory effects that result in up-regulation of surface expression of MHC molecules, tumor-associated antigens, or Fas on malignant cells, rendering them more susceptible to immune destruction. Preliminary results of clinical studies using combination strategies have demonstrated a postvaccination antigen cascade, prolonged time to disease progression, and improved overall survival. Several larger randomized trials are ongoing, and more are required to support these findings. 相似文献
1000.
V. E. Kataev O. I. Militsina I. Yu. Strobykina G. I. Kovylyaeva R. Z. Musin O. V. Fedorova G. L. Rusinov M. N. Zueva G. G. Mordovskoi A. G. Tolstikov 《Pharmaceutical Chemistry Journal》2006,40(9):473-475
Diesters based on isosteviol and dicarboxylic acids were synthesized and tested for antituberculous activity. Isosteviol and
some of its derivatives exhibit appreciable tuberculostatic properties in vitro, the activity being dependent on the length of the polymethylene spacer connecting two ent-beyeran fragments. The mechanism of the antituberculous action of isosteviol derivatives are discussed.
__________
Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 40, No. 9, pp. 12–13, September, 2006. 相似文献