全文获取类型
收费全文 | 3049篇 |
免费 | 253篇 |
国内免费 | 12篇 |
专业分类
耳鼻咽喉 | 19篇 |
儿科学 | 73篇 |
妇产科学 | 62篇 |
基础医学 | 442篇 |
口腔科学 | 45篇 |
临床医学 | 326篇 |
内科学 | 703篇 |
皮肤病学 | 17篇 |
神经病学 | 234篇 |
特种医学 | 311篇 |
外科学 | 291篇 |
综合类 | 45篇 |
一般理论 | 1篇 |
预防医学 | 411篇 |
眼科学 | 46篇 |
药学 | 203篇 |
中国医学 | 1篇 |
肿瘤学 | 84篇 |
出版年
2021年 | 37篇 |
2020年 | 24篇 |
2019年 | 35篇 |
2018年 | 35篇 |
2017年 | 41篇 |
2016年 | 33篇 |
2015年 | 43篇 |
2014年 | 71篇 |
2013年 | 80篇 |
2012年 | 114篇 |
2011年 | 117篇 |
2010年 | 72篇 |
2009年 | 73篇 |
2008年 | 133篇 |
2007年 | 139篇 |
2006年 | 125篇 |
2005年 | 104篇 |
2004年 | 103篇 |
2003年 | 116篇 |
2002年 | 101篇 |
2001年 | 125篇 |
2000年 | 111篇 |
1999年 | 98篇 |
1998年 | 48篇 |
1997年 | 49篇 |
1996年 | 43篇 |
1995年 | 39篇 |
1994年 | 51篇 |
1993年 | 42篇 |
1992年 | 80篇 |
1991年 | 72篇 |
1990年 | 80篇 |
1989年 | 86篇 |
1988年 | 88篇 |
1987年 | 68篇 |
1986年 | 62篇 |
1985年 | 67篇 |
1984年 | 62篇 |
1983年 | 50篇 |
1982年 | 30篇 |
1981年 | 38篇 |
1980年 | 35篇 |
1979年 | 29篇 |
1978年 | 31篇 |
1977年 | 24篇 |
1976年 | 30篇 |
1975年 | 16篇 |
1974年 | 25篇 |
1973年 | 16篇 |
1972年 | 15篇 |
排序方式: 共有3314条查询结果,搜索用时 31 毫秒
11.
12.
13.
Hemodynamically significant gastrointestinal tract hemorrhage is infrequently seen among patients with AIDS. During a 35-month period, we evaluated 37 AIDS patients with substantial gastrointestinal tract bleeding: 13 patients had upper gastrointestinal disease; 24 patients had colorectal disease. AIDS-associated lesions were identified as the etiology of the hemorrhage in 8 of 13 patients with upper and 9 of 24 patients with lower gastrointestinal tract bleeding. 相似文献
14.
Children With Chronic Physical Disorders: Maternal Reports of Their Psychological Adjustment 总被引:7,自引:4,他引:3
Wallander Jan L.; Varni James W.; Babani Lina; Banis Heather Tweddle; Wilcox Karen Thompson 《Journal of pediatric psychology》1988,13(2):197-212
Advances in biomedical science have resulted in dramatic improvementsin the medical care of chronically ill and handicapped children.Past measurement problems have resulted in a lack of clarityregarding the psychological adjustment of these children. Themothers of 270 chronically ill and handicapped children wereadministered the Child Behavior Checklist in an attempt to identifypatterns of behavioral functioning across six pediatric chronicdisorders: juvenile diabetes, spina bifida, hemophilia, chronicobesity, juvenile rheumatoid arthritis, and cerebral palsy.In general, it was found that children in all chronic disordergroups were perceived by their mothers as evidencing on theaverage more behavioral and social competence problems thanexpected based on norms for children in general. However, theirbehavioral and social adjustment was reported as better thanthat of a normative sample of children referred to mental healthclinics. There were essentially no differences between childrenwith different chronic disorders in terms of behavior problemsand social competence. The results were taken to support theview that these children were as a group at risk for adjustmentproblems. They were also discussed in terms of the noncategorialapproach, which suggests that similar psychosocial challengesare faced across pediatric chronic physical disorders. 相似文献
15.
Normal and diseased isolated lungs: high-resolution CT 总被引:8,自引:0,他引:8
16.
17.
The objective of this study was to compare caloric expenditure and substrate utilization during exercise begun at different time intervals following a standard test meal or in the fasted state. Eight physically fit women (aged 21-27 years) participated in four separate exercise trials. In three trials, the subjects consumed a 940-kcal meal following an overnight fast and began exercising either 30, 60, or 90 min after the meal. In the other trial, the subjects did not consume any breakfast prior to exercising. Energy expenditure and substrate utilization were determined by indirect calorimetry during the last 23 min of a 30-min run on a treadmill at an average work load of 62% VO2max. There were no significant differences among trials when comparing the total caloric expenditures (range: 215-219 kcal). However, the subjects oxidized significantly more fat (94.3 kcal) when they exercised on an empty stomach than when they exercised 60 or 90 min after the meal (71.6 and 68.8 kcal, respectively) (P less than 0.05). It was concluded that consumption of a meal prior to exercise does not increase the energy cost of the activity for physically fit women, but it does disrupt the pattern of substrate utilization, reducing the contribution of fat as an energy source. 相似文献
18.
19.
Systemic drug profiles of adult patients seen in an optometric outpatient setting were determined. The sample consisted of 502 subjects, of whom 214 were taking known medication, 267 were not taking drugs, and 21 subjects were taking unidentified medication. The most frequently used drugs and drug groups were identified and compared to a 1986 national survey that ranked the most frequently prescribed systemic medications. Drug distribution by age, sex, and race of the 22 most frequently prescribed drugs was determined. Implications for the ophthalmic practitioner are discussed. 相似文献
20.
Picotamide inhibition of excess in vitro thromboxane B2 release by colorectal mucosa in inflammatory bowel disease. 总被引:1,自引:0,他引:1
Collins CE Benson MJ Burnham WR Rampton DS 《Alimentary pharmacology & therapeutics》1996,10(3):315-320
BACKGROUND: Inflammatory bowel disease is associated with increased mucosal release of eicosanoids. Among these, thromboxane A2 has been proposed as a possible inflammatory mediator; its suppression may be a useful therapeutic option. METHODS: Using a tissue incubation technique, we compared release of immunoreactive thromboxane B2 by colonic biopsies from patients with ulcerative colitis, Crohn's disease and controls, and assessed the inhibitory effect of picotamide, a thromboxane synthesis inhibitor-receptor antagonist, which has been widely used in Italy for management of ischaemic heart and cerebrovascular disease. RESULTS: Increased amounts of thromboxane B2 were released from biopsies from patients with active ulcerative colitis (median 238 pg/20 min/mg wet weight (interquartile range 147- 325), n = 12) and active Crohn's disease (252 (174-450), 6) compared with those from patients with quiescent ulcerative colitis (95 (61- 140), 12) or Crohn's disease (105 (57-201), 13), or controls (136 (64- 206), 8). Incubation with picotamide at concentrations between 100 microM and 1 mM reduced thromboxane B2 release (IC50 890 microM). CONCLUSION: Since increased thromboxane A2 production may have pathogenetic importance, thromboxane synthesis inhibitor-receptor antagonists such as picotamide merit therapeutic trial in the management of inflammatory bowel disease. 相似文献