全文获取类型
收费全文 | 1277320篇 |
免费 | 99158篇 |
国内免费 | 1987篇 |
专业分类
耳鼻咽喉 | 18423篇 |
儿科学 | 44349篇 |
妇产科学 | 35008篇 |
基础医学 | 182162篇 |
口腔科学 | 33581篇 |
临床医学 | 111241篇 |
内科学 | 258212篇 |
皮肤病学 | 28020篇 |
神经病学 | 100356篇 |
特种医学 | 51203篇 |
外国民族医学 | 660篇 |
外科学 | 196376篇 |
综合类 | 27048篇 |
现状与发展 | 1篇 |
一般理论 | 377篇 |
预防医学 | 95715篇 |
眼科学 | 27912篇 |
药学 | 94761篇 |
2篇 | |
中国医学 | 2422篇 |
肿瘤学 | 70636篇 |
出版年
2018年 | 13132篇 |
2017年 | 9963篇 |
2016年 | 10898篇 |
2015年 | 12369篇 |
2014年 | 17163篇 |
2013年 | 26210篇 |
2012年 | 36016篇 |
2011年 | 38050篇 |
2010年 | 22798篇 |
2009年 | 21806篇 |
2008年 | 36634篇 |
2007年 | 39243篇 |
2006年 | 39498篇 |
2005年 | 38437篇 |
2004年 | 37589篇 |
2003年 | 36444篇 |
2002年 | 35794篇 |
2001年 | 63987篇 |
2000年 | 66495篇 |
1999年 | 56408篇 |
1998年 | 15128篇 |
1997年 | 13754篇 |
1996年 | 14195篇 |
1995年 | 13452篇 |
1994年 | 12766篇 |
1993年 | 11791篇 |
1992年 | 44554篇 |
1991年 | 43464篇 |
1990年 | 42217篇 |
1989年 | 40111篇 |
1988年 | 36894篇 |
1987年 | 36234篇 |
1986年 | 33619篇 |
1985年 | 32278篇 |
1984年 | 24136篇 |
1983年 | 20268篇 |
1982年 | 11723篇 |
1981年 | 10691篇 |
1980年 | 9515篇 |
1979年 | 21341篇 |
1978年 | 14821篇 |
1977年 | 12532篇 |
1976年 | 11693篇 |
1975年 | 12623篇 |
1974年 | 14661篇 |
1973年 | 14117篇 |
1972年 | 12944篇 |
1971年 | 11729篇 |
1970年 | 11050篇 |
1969年 | 10024篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
Symptomatic HIV infection of the CNS in a patient without clinical evidence of immune deficiency 总被引:1,自引:0,他引:1
A Beckett P Summergrad T Manschreck H Vitagliano M Henderson M L Buttolph M Jenike 《The American journal of psychiatry》1987,144(10):1342-1344
Major depression with psychotic features, dementia, and focal neurologic abnormalities appeared in a Haitian man without AIDS or other syndromes of immune compromise. Neurologic evaluation, including brain biopsy, was nondiagnostic, but CSF culture revealed human immunodeficiency virus (HIV). 相似文献
993.
L M Cortese D W Greenberger P J Schneider J A Bourret 《American journal of hospital pharmacy》1987,44(11):2514-2518
Perceptions of job characteristics and job satisfaction of central-area technicians and drug-administration technicians at The Ohio State University Hospitals were analyzed. A questionnaire was administered to 79 pharmacy drug-administration technicians; 44 central-area technicians; 10 pharmacy residents, who served as objective raters (5 in the central area and 5 in the decentral area); 13 central-area pharmacists; and 17 decentral-area pharmacists. Perceived job characteristics were measured with the Job Characteristics Inventory; job satisfaction was measured by the Minnesota Job Satisfaction Questionnaire. The two groups of technicians differed significantly in their perceptions of task identity, task significance, and dealing with others. Significantly greater autonomy in technicians' jobs was perceived to exist by pharmacists and raters in both areas than by technicians. Significantly greater task identity was perceived by the central-area technicians than by their raters, and significantly greater task importance was perceived by both groups of technicians than by their pharmacists and raters. Friendship opportunities were perceived to exist to a significantly greater degree by decentral pharmacists and raters than by the drug-administration technicians. In the institution studied, both central-area and drug-administration technicians tended to be dissatisfied with their jobs. Central-area technicians' satisfaction was influenced most by the technicians' relationships with their supervisors and the feelings of accomplishment they gained. Drug-administration technicians were most satisfied if they believed they had opportunities to use their abilities. Efforts to increase job satisfaction among pharmacy technicians should focus on increasing feedback and task identity. 相似文献
994.
995.
Although an uncommon cause of sexual dysfunction, hyperprolactinaemia is almost invariably associated with loss of libido and impotence in men. The finding of hyperprolactinaemia should prompt a systematic search for an underlying cause, particularly prolactin-secreting pituitary adenomas; in this condition, sexual dysfunction may antedate other complications of the pituitary tumour by many years. 相似文献
996.
J B Ubbink W J Serfontein P J Becker L S de Villiers 《The American journal of clinical nutrition》1987,46(1):78-85
Plasma pyridoxal-5'-phosphate and pyridoxal levels increased significantly (p less than 0.05) when single, oral bolus doses of pyridoxine were increased from 10 to 25 and from 25 to 50 mg in nine female volunteers. However, when the dose was increased to 100 mg, plasma pyridoxal-5'-phosphate levels did not differ significantly from those recorded after the 50 mg dose. Within 3 h plasma pyridoxal levels rose with a factor of 3.85 compared with the 50 mg dose but high pyridoxal levels were eliminated from the circulation. Renal clearance of pyridoxal remained a constant, low percentage (less than 2.0%) of each pyridoxine supplement in spite of the observed very high circulating pyridoxal levels. Pyridoxine supplementation is discussed in relation to circulating pyridoxal-5'-phosphate and pyridoxal availability for cellular metabolism. 相似文献
997.
From 1981 through 1985, the authors studied the changes in monthly nosocomial infection rates at the University of Virginia Hospital in Charlottesville, Virginia using the 95% confidence interval for infection rates as a marker of the efficacy of infection control activities. For a 99-month baseline period, monthly infection rates were calculated and the 95% confidence interval was established. In the 60 study months, each monthly rate was compared with the 95% confidence interval for that particular month. At the end of each study year, the monthly infection rates were incorporated into the existing confidence interval. Of 60 monthly rates during the study period, 30 were below the confidence interval (p less than 0.00001), two were above the confidence interval (p = 0.23), and 28 were within the confidence interval. Since there was no reduction in surveillance activity, patient case-mix index, or laboratory sensitivity for organism recovery, these results suggest that monthly nosocomial infection rates at this hospital have decreased when compared with the baseline period. The use of the 95% confidence interval may provide a measure of the efficacy of infection control activities, suggest temporal intervals requiring more intensive infection surveillance, and provide a method for examining the variability in monthly infection rates. 相似文献
998.
Behavioral methods and research issues in the management of the adult dental patient 总被引:1,自引:1,他引:0
P Milgrom 《Anesthesia progress》1986,33(1):5-9
999.
Radiation-induced meningioma. 3 cases 总被引:1,自引:0,他引:1
During the same year (1984), we have seen 3 cases of meningiomas following radiation therapy of the brain for previously diagnosed tumors. A causal relationship between irradiation and meningioma has been postulated. Nevertheless, the coincidental occurrence in same patient of two different histological lesions is possible. The neoplasms developed after irradiation are of mesenchymal origin; they are fibrosarcomas, osteogenic sarcomas and meningiomas. 相似文献
1000.
Effect of age and diet on cyclic nucleotide concentrations in the intestinal mucosa of developing rats 总被引:1,自引:0,他引:1
Mucosa isolated from the proximal third of the small intestine of infant rats had much lower cyclic nucleotide concentrations (expressed both per unit wet weight and per unit DNA content) than those determined in the intestinal wall. The steady-state concentrations of both cyclic AMP and cyclic GMP in jejunum showed dramatic increases during the first 5 d post partum. Another increase in cyclic nucleotide concentrations was observed in the isolated mucosa between d 15 and 21. Starvation for 24 h always resulted in lower intestinal cyclic nucleotide concentrations than those of the fed littermates. This effect was more pronounced in younger animals and more evident for cyclic AMP values. Three-week-old rats fed a high carbohydrate diet for 24-48 h exhibited more pronounced elevations in the concentrations of cyclic nucleotides from the jejunal mucosa than did rats fed a high fat diet. 相似文献