全文获取类型
收费全文 | 29102篇 |
免费 | 2223篇 |
国内免费 | 102篇 |
专业分类
耳鼻咽喉 | 308篇 |
儿科学 | 882篇 |
妇产科学 | 624篇 |
基础医学 | 4246篇 |
口腔科学 | 477篇 |
临床医学 | 2768篇 |
内科学 | 5742篇 |
皮肤病学 | 493篇 |
神经病学 | 2768篇 |
特种医学 | 1026篇 |
外科学 | 4184篇 |
综合类 | 688篇 |
现状与发展 | 1篇 |
一般理论 | 31篇 |
预防医学 | 2314篇 |
眼科学 | 863篇 |
药学 | 1941篇 |
中国医学 | 49篇 |
肿瘤学 | 2022篇 |
出版年
2023年 | 116篇 |
2022年 | 148篇 |
2021年 | 657篇 |
2020年 | 341篇 |
2019年 | 566篇 |
2018年 | 705篇 |
2017年 | 450篇 |
2016年 | 550篇 |
2015年 | 633篇 |
2014年 | 800篇 |
2013年 | 1279篇 |
2012年 | 1834篇 |
2011年 | 1799篇 |
2010年 | 1078篇 |
2009年 | 986篇 |
2008年 | 1647篇 |
2007年 | 1707篇 |
2006年 | 1537篇 |
2005年 | 1699篇 |
2004年 | 1631篇 |
2003年 | 1511篇 |
2002年 | 1430篇 |
2001年 | 456篇 |
2000年 | 476篇 |
1999年 | 465篇 |
1998年 | 348篇 |
1997年 | 283篇 |
1996年 | 252篇 |
1995年 | 264篇 |
1994年 | 203篇 |
1993年 | 240篇 |
1992年 | 330篇 |
1991年 | 323篇 |
1990年 | 312篇 |
1989年 | 312篇 |
1988年 | 279篇 |
1987年 | 256篇 |
1986年 | 245篇 |
1985年 | 267篇 |
1984年 | 227篇 |
1983年 | 185篇 |
1982年 | 197篇 |
1981年 | 195篇 |
1980年 | 168篇 |
1979年 | 137篇 |
1978年 | 119篇 |
1977年 | 124篇 |
1976年 | 133篇 |
1975年 | 118篇 |
1974年 | 147篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
151.
Jonathan C. Craig Les M. Irwig James Christie Albert Lam Ella Onikul John F. Knight Premala Sureshkumar L. Paul Roy 《Pediatric nephrology (Berlin, Germany)》1997,11(4):455-459
Variability in the interpretation of micturating cystourethrography by paediatric radiologists for the diagnosis of vesicoureteric
reflux in children was evaluated. All 265 micturating cystourethrograms (MCUs) that were available from 304 consecutive children
aged 0.5 – 61 months – who were investigated after their first urine infection between 1993 and 1995 as part of a prospective
cohort study – were selected for interpretation. Three experienced paediatric radiologists from the same department independently
interpreted the MCUs according to the grading system of the International Reflux Study in Children, from grades 0 to V, with
the presence of intrarenal reflux also noted. Apart from being informed that urine infection was the indication for the MCU,
no other clinical information was given to the radiologists. The indices of variability used were the percentage of agreement
and the kappa statistic, expressed as a percentage. Both measures were weighted with integers representing the number of categories
from perfect agreement. Disagreement was analysed for children and kidneys. For the diagnosis of vesicoureteric reflux in
individual patients, including grade, the percentage of agreement was 96% – 97% (kappa 90% – 91%) and the weighted percentage
of agreement was 96% – 98% (weighted kappa 93% – 94%). The same high level of agreement was present for individual kidneys,
with a percentage of agreement of 97% – 98% (kappa 89% – 92%) and a weighted percentage of agreement of 98% – 99% (kappa 94% – 95%).
There was near perfect agreement in the interpretation of radiological micturating cystourethrography among three experienced
paediatric radiologists for the diagnosis and grade of vesicoureteric reflux. Any variations in the medical care of children
suspected of having vesicoureteric reflux are not explained by differences in the reporting of this diagnostic test.
Received June 19, 1996; received in revised form November 1, 1996; accepted December 6, 1996 相似文献
152.
153.
154.
The intraocular distribution of fosfomycin was studied in 32 patients undergoing cataract surgery and or vitrectomy and in 8 rabbits after experimental infection of one eye by Staphylococcus aureus. In subjects perfused with 4 g of fosfomycin, concentrations ranged from 14 to 18.8 mg/l in aqueous humour (AH) and from 8 to 12.5 mg/l in vitreous fluid (VF) between 1 and 6 hours after the end of the perfusion; these levels were higher than MICs for 80-90 per cent of bacteria found in endophthalmitis. In rabbits the concentration in infected eyes with respect to healthy eyes was found to be from 2.5 to 5 times in AH and from 4.9 to 19.2 times higher in VF. Therefore fosfomycin in association with third generation cephalosporins (ceftriaxone) or with new quinolones can be recommended in the prevention and early treatment of endophthalmitis. 相似文献
155.
Xu H Hofmeyr J Roy C Fraser W 《BJOG : an international journal of obstetrics and gynaecology》2007,114(4):383-390
BACKGROUND: Amnioinfusion (AI) is thought to dilute meconium when present in the amniotic fluid and so reduces the risk of meconium aspiration. OBJECTIVES: To evaluate if AI reduces meconium aspiration syndrome (MAS) and other indicators of morbidity in babies born to women with meconium-stained amniotic fluid (MSAF). SEARCH STRATEGY: PubMed, Medline, EMBASE, and the Cochrane Controlled Trials Register from January 1980 to May 30, 2005, using the keywords 'amnioinfusion' and 'meconium'. SELECTION CRITERIA: Randomised trials comparing AI with no AI for women in labour with MSAF. Trial quality was evaluated using pre-established criteria. DATA COLLECTION AND ANALYSIS: The following morbidity indicators were assessed: MAS, 5-minute Apgar score < 7, arterial cord pH < 7.2, and caesarean section. Studies were stratified according to the level of peripartum surveillance (standard versus limited). Typical relative risks (RRs) with their 95% confidence intervals were calculated for each outcome using a random effects model. MAIN RESULTS: In clinical settings with standard peripartum surveillance, we found no evidence that AI reduced the risk of MAS (RR 0.59, 95% CI 0.28-1.25), 5-minute Apgar score < 7 (RR 0.90, 95% CI 0.58-1.41), or caesarean delivery (RR 0.89, 95% CI 0.73-1.10). In clinical settings with limited peripartum surveillance, AI appeared to reduce the risk of MAS (RR 0.25, 95% CI 0.13-0.47). CONCLUSION: In clinical settings with standard peripartum surveillance, the evidence does not support the use of AI for MSAF. In settings with limited peripartum surveillance, where complications of MSAF are common, AI appears to reduce the risk of MAS. However, this finding requires confirmation by further studies. 相似文献
156.
Crohn''s disease is well known for its multiple intestinal complications. The chronic nature and fibrous inflammation which invariably accompanies this disease explains the relative rarity of free intestinal perforation. The true incidence of free bowel perforation is difficult to assess but 1-2% is the anticipated occurrence during the course of illness. We present a case of Crohn''s disease which presented for the first time with acute colonic perforation, an extremely rare entity, and review the current world literature. 相似文献
157.
A 69-year-old male with blepharospasm unresponsive to several medications who was successfully treated with quetiapine is described. His symptoms were largely alleviated by low doses, but he experienced sedation, which permitted him to take the medication at bedtime only. 相似文献
158.
159.
Twenty-nine infants (2-4 months old), with pathological gastroesophageal reflux assessed by 24-h esophageal pH monitoring, were studied. Cisapride or placebo was randomly added to positional treatment, prone-antiTrendelenburg position, which was applied to all infants. The pH monitoring was repeated after 13-16 days of treatment and revealed a significant improvement in both groups for most parameters. But the number of reflux episodes lasting longer than 5 min and the total number of reflux episodes had not decreased significantly in the placebo group. Only in the number of reflux episodes lasting longer than 5 min was improvement during treatment significantly greater in the cisapride group. This suggests cisapride both prevented reflux and improved esophageal clearance. These results suggest that in addition to other therapeutic measurements, such as positional treatment (which was previously demonstrated to be effective in this age group), cisapride might be of benefit in the treatment of gastroesophageal reflux disease. 相似文献
160.
Intraocular diffusion of piperacillin was studied in 42 patients scheduled for cataract surgery (n = 35) or vitrectomy (n = 7). Piperacillin was administered intravenously (4 g/injection). Thirty-four patients were given a single dose and 8 were given two doses 12 hours apart. Peak piperacillin levels in the aqueous (7.3 mg/l) occurred one hour after the injection; levels in the vitreous were low (less than 0.6 mg/l). Intraocular diffusion of piperacillin was also studied in rabbits with an experimental Staphylococcus epidermidis infection of one eye; the other eye served as the control. In pigmented rabbits (6 Fauve de Bourgogne animals), increased diffusion and decreased elimination of piperacillin were seen in the aqueous, iris and cornea of the infected eyes, as compared with uninfected control eyes. In albino rabbits (6 New Zealand animals), results were less conclusive, with a difference between the infected and healthy eyes appearing only during the second hour following the injection. The good diffusion of piperacillin in the aqueous, especially in infected eyes (at least in rabbits), suggests that this drug may be useful for the treatment of ocular infections provided it is initiated early and given in combination with another antimicrobial exhibiting good intraocular diffusion. 相似文献