全文获取类型
收费全文 | 1443513篇 |
免费 | 109723篇 |
国内免费 | 4778篇 |
专业分类
耳鼻咽喉 | 18172篇 |
儿科学 | 46331篇 |
妇产科学 | 38387篇 |
基础医学 | 211748篇 |
口腔科学 | 38378篇 |
临床医学 | 140457篇 |
内科学 | 280465篇 |
皮肤病学 | 27871篇 |
神经病学 | 121417篇 |
特种医学 | 52616篇 |
外国民族医学 | 366篇 |
外科学 | 201994篇 |
综合类 | 30420篇 |
现状与发展 | 2篇 |
一般理论 | 623篇 |
预防医学 | 124686篇 |
眼科学 | 31490篇 |
药学 | 106530篇 |
8篇 | |
中国医学 | 3325篇 |
肿瘤学 | 82728篇 |
出版年
2021年 | 12941篇 |
2019年 | 13554篇 |
2018年 | 18687篇 |
2017年 | 13974篇 |
2016年 | 15036篇 |
2015年 | 17346篇 |
2014年 | 23976篇 |
2013年 | 37047篇 |
2012年 | 51316篇 |
2011年 | 54456篇 |
2010年 | 31322篇 |
2009年 | 28789篇 |
2008年 | 49473篇 |
2007年 | 52316篇 |
2006年 | 52082篇 |
2005年 | 50600篇 |
2004年 | 48334篇 |
2003年 | 45853篇 |
2002年 | 44486篇 |
2001年 | 61906篇 |
2000年 | 63351篇 |
1999年 | 53382篇 |
1998年 | 15919篇 |
1997年 | 14360篇 |
1996年 | 14146篇 |
1995年 | 13450篇 |
1994年 | 12486篇 |
1993年 | 11746篇 |
1992年 | 42251篇 |
1991年 | 41457篇 |
1990年 | 40045篇 |
1989年 | 37939篇 |
1988年 | 35196篇 |
1987年 | 34290篇 |
1986年 | 32777篇 |
1985年 | 31327篇 |
1984年 | 23780篇 |
1983年 | 20290篇 |
1982年 | 12692篇 |
1981年 | 11224篇 |
1979年 | 21320篇 |
1978年 | 15355篇 |
1977年 | 12561篇 |
1976年 | 12317篇 |
1975年 | 12487篇 |
1974年 | 15198篇 |
1973年 | 14846篇 |
1972年 | 13598篇 |
1971年 | 12690篇 |
1970年 | 11716篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
Cancer risk after evaluation for infertility 总被引:3,自引:0,他引:3
L A Brinton L J Melton G D Malkasian A Bond R Hoover 《American journal of epidemiology》1989,129(4):712-722
To evaluate cancer risk by various causes of infertility, the authors conducted a retrospective cohort study among 2,335 women evaluated for infertility at the Mayo Clinic between 1935 and 1964. Most cancers occurred at expected frequencies, with the exception of cancers of the thyroid (standardized incidence ratio (SIR) = 2.6) and other endocrine glands (SIR = 6.7), although analyses were based on small numbers. Patients with progesterone deficiencies (31 per cent of the study subjects) had a 20 per cent higher cancer risk than did those with other causes of infertility, with excesses deriving primarily from cancers of the lung, cervix, ovary, and thyroid and from melanoma. Breast cancer risk, however, was not elevated in either patients with progesterone deficiencies (SIR = 0.9) or patients with other causes of infertility (SIR = 1.0). Examination of other parameters of infertility, including age at evaluation, type of infertility (primary vs. secondary), and years of attempted conception, showed no elevated risks of breast cancer in any subgroup. These results fail to support previous studies that have linked progesterone deficiencies among infertile women to elevated breast cancer risk. However, the data suggest a possible involvement of a progesterone deficiency in the etiology of other cancers, particularly thyroid cancer and melanoma. 相似文献
993.
Issues in carrying out epidemiologic research in the elderly 总被引:3,自引:0,他引:3
994.
995.
A general overview of the literature concerning the development of diabetic neuropathic arthropathy is discussed. A case report is presented dealing with spontaneous fractures of the lesser metatarsal in a patient with an amputated hallux and peripheral neuropathy secondary to diabetes mellitus. 相似文献
996.
997.
Pradip K. Rustagi Tin Han Lynn Ziolkowski Deborah L. Farolino Mark S. Currie Gerald L. Logue 《British journal of haematology》1987,66(4):461-465
The anti-granulocyte activity of serum from patients with B-cell chronic lymphocytic leukaemia (CLL) and other lymphoproliferative disorders was investigated. Granulocyte-binding IgG was measured in 34 patients with CLL, 13 patients with hairy cell leukaemia, one patient with prolymphocytic leukaemia, two patients with Sézary cell leukaemia, and seven patients with chronic T-cell lymphocytosis who had a predominance of circulating large granular lymphocytes. Anti-granulocyte activity was absent in CLL and its variants, but present in the majority of granulocytopenic patients with chronic T-cell lymphocytosis. In one of these patients, granulocytopenia was associated with complement-activating IgG granulocyte antibody. Thus, antibody-mediated granulocyte injury appears to be an unusual occurrence in chronic lymphocytic leukaemia, but is a frequent complication of chronic T-cell lymphocytosis. 相似文献
998.
Circulating immune complex levels in patients with schistosomiasis and complications 总被引:3,自引:0,他引:3
A M Ghanem F N Boctor S Bassily H Shaheen A Ahmed L Garges 《Transactions of the Royal Society of Tropical Medicine and Hygiene》1987,81(5):773-777
Circulating immune complexes (CIC), adult schistosome antibody, and total immunoglobulin concentrations were estimated in sera from 35 chronic Schistosoma mansoni patients with different infection intensities and different pathological complications. High CIC levels were present in about one-third (10/35) of the sera. Most of the patients (9/10) with elevated CIC levels also had hepatomegaly or hepatosplenomegaly. This finding is significant in the pathogenesis of schistosomal liver fibrosis and may also apply to other liver diseases, especially cirrhosis. No correlation was found between infection intensity as judged by stool egg counts and CIC levels. A reverse relationship was observed between the level of anti-adult worm IgG and CIC levels. CIC levels were elevated within 7 and 28 days after treatment in most patients. Hypergammaglobulinaemia was detected in most sera. 相似文献
999.
S. Ahmed A. L. Sparnon J. P. Savage H. A. Boucaut A. J. Smith 《ANZ journal of surgery》1986,56(9):675-680
One hundred and one children over 1 year of age have had surgery for pelviureteric obstruction over an 11 year period. The common clinical features were abdominal pain, urinary infection or haematuria, but number presented as an incidental finding. Less commonly, the patients presented with an abdominal mass or with hypertension. The diagnosis was usually made on intravenous pyelography (IVP) but in the latter part of the series, renal nuclide scan (RNS) and ultrasonography (US) were preferred. Ninety–three patients had unilateral pyeloplasty, three had bilateral pyeloplasty and five had nephrectomy or heminephrectomy. Whereas initially nephrostomy drainage was used in the majority of patients after pyeloplasty, trend away from nephrostomy evolved in the latter part of the series. With experience, the incidence of postoperative complications was also reduced and there was reduction in the period of hospitalization. Clinical results were consistently satisfactory. Postoperative assessment after pyeloplasty was made by IVP and/or RNS and also US. A review of these investigations showed that RNS provided more factual information of the result when compared with the IVP. 相似文献
1000.
L J Findley 《British journal of hospital medicine》1986,35(6):388, 390-388, 392
Essential tremor is a common disorder whose aetiology is unknown. Characteristically it is present on maintaining posture, absent at rest, and not made significantly worse with movement. 相似文献