全文获取类型
收费全文 | 1643671篇 |
免费 | 123540篇 |
国内免费 | 7040篇 |
专业分类
耳鼻咽喉 | 21113篇 |
儿科学 | 53412篇 |
妇产科学 | 45037篇 |
基础医学 | 225570篇 |
口腔科学 | 46214篇 |
临床医学 | 142109篇 |
内科学 | 337919篇 |
皮肤病学 | 39726篇 |
神经病学 | 131742篇 |
特种医学 | 67939篇 |
外国民族医学 | 371篇 |
外科学 | 251772篇 |
综合类 | 33167篇 |
现状与发展 | 2篇 |
一般理论 | 438篇 |
预防医学 | 137771篇 |
眼科学 | 35718篇 |
药学 | 116314篇 |
7篇 | |
中国医学 | 2911篇 |
肿瘤学 | 84999篇 |
出版年
2018年 | 20781篇 |
2017年 | 16788篇 |
2016年 | 18217篇 |
2015年 | 21264篇 |
2014年 | 26691篇 |
2013年 | 37534篇 |
2012年 | 53470篇 |
2011年 | 52237篇 |
2010年 | 30748篇 |
2009年 | 30311篇 |
2008年 | 45637篇 |
2007年 | 49229篇 |
2006年 | 50264篇 |
2005年 | 55946篇 |
2004年 | 55162篇 |
2003年 | 49646篇 |
2002年 | 42979篇 |
2001年 | 73430篇 |
2000年 | 73710篇 |
1999年 | 64502篇 |
1998年 | 17727篇 |
1997年 | 15593篇 |
1996年 | 16664篇 |
1995年 | 16836篇 |
1994年 | 15655篇 |
1993年 | 14583篇 |
1992年 | 54576篇 |
1991年 | 53304篇 |
1990年 | 51719篇 |
1989年 | 49029篇 |
1988年 | 45566篇 |
1987年 | 44663篇 |
1986年 | 42206篇 |
1985年 | 40344篇 |
1984年 | 30302篇 |
1983年 | 25336篇 |
1982年 | 15108篇 |
1981年 | 13468篇 |
1979年 | 27918篇 |
1978年 | 19737篇 |
1977年 | 16603篇 |
1976年 | 15137篇 |
1975年 | 16577篇 |
1974年 | 19779篇 |
1973年 | 18794篇 |
1972年 | 17527篇 |
1971年 | 16337篇 |
1970年 | 15031篇 |
1969年 | 14146篇 |
1968年 | 13283篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
The multiple regression analysis of twin data in which a cotwin's score is predicted from that of a proband (the member of a twin pair selected because of a deviant score) and the coefficient of relationship provides a powerful test of genetic etiology (DeFries and Fulker: Behav Genet 15:467-473, 1985). Moreover, when an augmented model containing an interaction term is fitted to the same data set, direct estimates of heritability (h2) and the proportion of variance owing to shared environmental influences (c2) are also obtained. In the present paper, the expected partial regression coefficients estimated from these models are derived, and the flexibility of the general approach is illustrated. An extended model is formulated for the analysis of data from combined samples of affected and control twin pairs that yields tests for differential h2 and c2 in the two groups as well as pooled estimates of these parameters. The application of these models is illustrated by an analysis of data from reading-disabled and control twin pairs. Because of the ease, flexibility, and utility of the multiple regression analysis of twin data, it is an appealing alternative to more traditional model-fitting approaches. 相似文献
992.
H Hultgren P Peduzzi W Shapiro D van Heeckeren 《Progress in cardiovascular diseases》1986,28(4):279-284
993.
D N Fairbanks 《American family physician》1986,33(2):205-211
Snoring means obstructive breathing during sleep, and its most exaggerated form is obstructive sleep apnea. Mild snoring may respond to simple self-help remedies. Heavy snoring responds well to the surgical removal or reconstruction of obstructive elements in the hypopharynx, nasopharynx or nasal passages. 相似文献
994.
995.
Pyomyositis occurs infrequently in temperate climates. The fulminating peracute form caused by group A Streptococcus is exceedingly rare. We present two children with streptococcal pyomyositis. One child was admitted in septic shock and required intensive supportive care during the acute stage of his illness. Persistent swelling and tenderness of his left thigh presented a diagnostic problem, which was eventually resolved with the aid of computerized tomography. Despite appropriate antibiotic therapy from the onset of illness, surgical debridement of the affected muscle was necessary. The second child presented with pyomyositis of the left paravertebral muscles and signs of incipient shock but did well on antibiotic therapy alone. 相似文献
996.
997.
Bone mineral density testing in healthy postmenopausal women. The role of clinical risk factor assessment in determining fracture risk. 总被引:5,自引:0,他引:5
William D Leslie Colleen Metge Elizabeth A Salamon C Kin Yuen 《Journal of clinical densitometry》2002,5(2):117-130
The ease of measurement and the quantitative nature of bone mineral densitometry (BMD) is clinically appealing. Despite BMD's proven capability to stratify fracture risk, data indicate that clinical risk factors provide complementary information on fracture susceptibility that is independent of BMD. Methods to quantify fracture risk using both clinical and BMD variables would have great appeal for clinical decision-making. We describe a procedure for quantifying hip fracture risk (5-yr and remaining lifetime) based on (1) the individual's age alone (base model, assuming average clinical risk factors and bone density), (2) incorporation of multiple patient-specific clinical risk factor data in the base model, and (3) incorporation of both patient-specific clinical risk factor data and BMD results. 相似文献
998.
P Leprince F Heloire B Eymard P Léger D Duboc A Pavie 《The Journal of heart and lung transplantation》2002,21(7):822-824
A 28-year-old male patient diagnosed with Becker muscular dystrophy (BMD)-associated cardiomyopathy was successfully bridged to transplantation with the Cardiowest total artificial heart. Dramatic improvement of muscular functional status occurred following transplantation. 相似文献
999.
Compromise of immune function in obstructive jaundice. 总被引:5,自引:0,他引:5
1000.