全文获取类型
收费全文 | 3488104篇 |
免费 | 282798篇 |
国内免费 | 14593篇 |
专业分类
耳鼻咽喉 | 48462篇 |
儿科学 | 106933篇 |
妇产科学 | 91282篇 |
基础医学 | 546979篇 |
口腔科学 | 96880篇 |
临床医学 | 308370篇 |
内科学 | 618217篇 |
皮肤病学 | 93045篇 |
神经病学 | 297935篇 |
特种医学 | 138869篇 |
外国民族医学 | 453篇 |
外科学 | 543370篇 |
综合类 | 107087篇 |
现状与发展 | 24篇 |
一般理论 | 2262篇 |
预防医学 | 284315篇 |
眼科学 | 79626篇 |
药学 | 242983篇 |
23篇 | |
中国医学 | 10347篇 |
肿瘤学 | 168033篇 |
出版年
2021年 | 54914篇 |
2020年 | 35040篇 |
2019年 | 58025篇 |
2018年 | 70835篇 |
2017年 | 54089篇 |
2016年 | 59844篇 |
2015年 | 73981篇 |
2014年 | 108169篇 |
2013年 | 173358篇 |
2012年 | 90088篇 |
2011年 | 89158篇 |
2010年 | 115510篇 |
2009年 | 120724篇 |
2008年 | 77092篇 |
2007年 | 80620篇 |
2006年 | 91464篇 |
2005年 | 86784篇 |
2004年 | 89024篇 |
2003年 | 80385篇 |
2002年 | 70698篇 |
2001年 | 109274篇 |
2000年 | 102388篇 |
1999年 | 101323篇 |
1998年 | 65231篇 |
1997年 | 63132篇 |
1996年 | 60647篇 |
1995年 | 56092篇 |
1994年 | 50324篇 |
1993年 | 47019篇 |
1992年 | 71714篇 |
1991年 | 68015篇 |
1990年 | 64993篇 |
1989年 | 64335篇 |
1988年 | 60216篇 |
1987年 | 58840篇 |
1986年 | 56328篇 |
1985年 | 55964篇 |
1984年 | 50483篇 |
1983年 | 45770篇 |
1982年 | 42318篇 |
1981年 | 39785篇 |
1980年 | 37627篇 |
1979年 | 42935篇 |
1978年 | 37352篇 |
1977年 | 34266篇 |
1976年 | 31033篇 |
1975年 | 30688篇 |
1974年 | 32403篇 |
1973年 | 31074篇 |
1972年 | 29501篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
Thirty-nine primary surgical cases for correction of congenital aural atresia were reviewed for complications and long-term hearing results. Hearing averages of 25 dB for mild atresia, 40 dB for moderate atresia, and 46 dB for severe atresia were obtained. Serviceable hearing was achieved in 64% of the cases. The two most frequent complications were stenosis and recurrent infections of the cavity and canal skin, with an incidence of 33% and 31%, respectively. Use of split-thickness instead of full-thickness skin graft was associated with fewer complications. The goal of this review is also to share the experience of the senior author in the management of this complex problem. 相似文献
993.
A. Trovato S. Kirjavainen E. M. Galati A. M. Forestieri L. Iauk 《Phytotherapy research : PTR》1995,9(8):591-593
The decoction of Sclerocarya birroea Hochst. shows hypoglycaemic effects, an increase in plasma IRI in normal rats and an incremented oral-glucose tolerance. The decoction is also active against diet-induced hypercholesterolaemia. 相似文献
994.
Development of an auxotrophic oral live Shigella flexneri vaccine 总被引:11,自引:0,他引:11
An oral live attenuated Shigella flexneri vaccine candidate strain was constructed by making it auxotrophic and dependent on aromatic metabolites not available in mammalian tissues. An aroD gene of Escherichia coli K12 strain NK 5131, inactivated by insertion in it of the Tn 10 transposon, was transduced using phage P1 into a virulent S. flexneri serotype Y strain (Sfl 1) isolated from a patient with bacillary dysentery. One of the transductant strains Sfl 114 was found to invade HeLa cells in vitro, to cause plaque formation in HeLa monolayers (i.e. maintain intracellular multiplication in vitro), but to be unable to cause keratoconjunctivitis in guinea-pig eyes. When the strain was fed to Macacca fascicularis monkeys it was well tolerated, excreted for 1-4 days, and found to elicit a local intestinal sIgA and serum IgA, IgM and IgG responses. Monkeys challenged with 100 ID50 dose (1 X 10(11) bacteria) of the virulent parent Sfl 1 strain were completely protected from development of diarrhoea. Coloscopy of the monkeys and the sampling of intestinal biopsies showed that the vaccine protected against the surface epithelial erosions and ulcerations seen in unimmunized monkeys. Killing of invading virulent shigellae apparently took place intracellularly in the mucosa suggesting that cellular immune mechanisms played a role in the elicited host defence. The constructed S. flexneri Sfl 114 strain has the properties of a promising shigella vaccine and will next be the subject of studies with human volunteers. 相似文献
995.
This study surveyed male and female athletes from 22 midwesterncolleges and universities regarding behaviors and attitudesassociated with anorexia nervosa and bulimia nervosa. The responserate was 66% (N= 695) and the findings indicated that the bodyimage of some athletes may be distorted; one-seventh perceivedthemselves as fat even though they were not. Many athletes seemedpreoccupied with food and weight; almost one-third reportedroutinely thinking about food and weight and more than one-thirdreported dramatic annual weight fluctuations (9 lb or greater)related to bingeing and fasting. Athletes also did not feelin control when they ate and their habits related to food consumptionappeared to be extreme; one-tenth reported a lack of controlwhen they ate, more than one-third binged, one-twentieth ateuntil they were physically ill, and a similar proportion preferrednot to eat in the presence of others. In addition, it was foundthat as many men as women athletes reported these perceptionsbut significant sex differences were noted for specific items.It was suggested that behaviors and attitudes be viewed on acontinuum with normals at one end, eating disordered individuals at the other end,and college athletes in between. Health education that focuseson behaviors and attitudes as symptoms of eating disorders wasrecommended for athletes and those working closely with athletes.Future research was suggested to determine reasons for the undesirablebehaviors and attitudes and to study the onset, development,long-term effects and whether these behaviors and attitudeslead to an eating disorder. 相似文献
996.
To study the effect of alcohol on glucose and insulin metabolism,a simultaneous infusion of glucose and insulin was given for150 min to healthy volunteers, once during alcohol and onceduring calorie-free gingerale (control) ingestion. During alcoholintake, the average steady-state (between 100 and 150 min) glucoseof 5.44±0.39 mmol/1. and the average steady-state insulinof 6.3±1.1 ng/ml were significantly higher than those(4.0±0.39 mmol/1. of glucose and 4.4±0.6 ng/mlof insulin) observed during the control state. Despite the highersteady-state insulin concentrations, the glucose metabolismwas significantly less during alcohol ingestion. These findingssuggest alcohol-induced impairment in glucose metabolism iscaused by a decreased tissue sensitivity to insulin. 相似文献
997.
Birth weight on 12,644 singleton infants from 6,196 sibships born in Maryland between 1980 and 1984 were used to estimate the effects of nine maternal and infant covariates on the sibship correlation in birth weight. Assuming a homogeneous correlation across all families, the estimated intraclass correlation was 0.4664 (+/- 0.0099). This high sibship correlation makes it possible to predict, with reasonable accuracy, the birth weight of a child given information on previous sibs, as well as covariates on the mother and/or infant pertinent to a given pregnancy. The reduction in variance associated with incorporating information on the nine covariates used here was approximately equal to that obtained by conditioning on a single previous sib. Testing for heterogeneity in correlation among different groups of families showed that a crude measure of parity (first live birth vs. other), time between births, mother's marital status, and maternal age at the birth of the last child significantly influenced the sibship correlation in birth weight. 相似文献
998.
H Bussey C Quandt R Rospond W Loesch 《The Journal of the American Board of Family Practice / American Board of Family Practice》1988,1(4):282-287
One of our patients had trouble maintaining therapeutic and safe levels of theophylline, even though we were careful in planning and monitoring her drug regimen. This case report shows how we were able to use principles of pharmacokinetics to distinguish among plausible explanations for her experience. We discovered that she was not taking the drug consistently as prescribed and that supervised administration resolved apparent contradictions between doses and serum levels. We believe that physicians can use the same information and methods that we used to get better and safer results from theophylline therapy. 相似文献
999.
1000.