全文获取类型
收费全文 | 1695546篇 |
免费 | 123335篇 |
国内免费 | 3781篇 |
专业分类
耳鼻咽喉 | 21730篇 |
儿科学 | 55634篇 |
妇产科学 | 46151篇 |
基础医学 | 241205篇 |
口腔科学 | 48741篇 |
临床医学 | 151304篇 |
内科学 | 333482篇 |
皮肤病学 | 38651篇 |
神经病学 | 131136篇 |
特种医学 | 63868篇 |
外国民族医学 | 242篇 |
外科学 | 257220篇 |
综合类 | 38946篇 |
现状与发展 | 4篇 |
一般理论 | 531篇 |
预防医学 | 124223篇 |
眼科学 | 40211篇 |
药学 | 123602篇 |
7篇 | |
中国医学 | 4475篇 |
肿瘤学 | 101299篇 |
出版年
2021年 | 12785篇 |
2019年 | 13521篇 |
2018年 | 19950篇 |
2017年 | 15213篇 |
2016年 | 16613篇 |
2015年 | 18957篇 |
2014年 | 26212篇 |
2013年 | 37940篇 |
2012年 | 52724篇 |
2011年 | 55415篇 |
2010年 | 32769篇 |
2009年 | 30691篇 |
2008年 | 51514篇 |
2007年 | 54793篇 |
2006年 | 55252篇 |
2005年 | 52535篇 |
2004年 | 50737篇 |
2003年 | 48147篇 |
2002年 | 46366篇 |
2001年 | 91782篇 |
2000年 | 93605篇 |
1999年 | 76959篇 |
1998年 | 19717篇 |
1997年 | 17267篇 |
1996年 | 17391篇 |
1995年 | 16742篇 |
1994年 | 15289篇 |
1993年 | 14071篇 |
1992年 | 57381篇 |
1991年 | 55270篇 |
1990年 | 52970篇 |
1989年 | 50747篇 |
1988年 | 46131篇 |
1987年 | 44937篇 |
1986年 | 42226篇 |
1985年 | 39987篇 |
1984年 | 29348篇 |
1983年 | 24908篇 |
1982年 | 13898篇 |
1979年 | 25529篇 |
1978年 | 17574篇 |
1977年 | 14906篇 |
1976年 | 13874篇 |
1975年 | 14563篇 |
1974年 | 17630篇 |
1973年 | 16944篇 |
1972年 | 15673篇 |
1971年 | 14453篇 |
1970年 | 13431篇 |
1969年 | 12517篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
861.
Determinants of all causes of death in samples of Italian middle-aged men followed up for 25 years. 总被引:2,自引:2,他引:0 下载免费PDF全文
A Menotti S Mariotti F Seccareccia S Torsello F Dima 《Journal of epidemiology and community health》1987,41(3):243-250
A total of 1712 men aged 40 to 59 years in two rural cohorts of northern and central Italy have been followed up for 25 years after an entry examination in 1960. Forty one individual characteristics have been considered as possible predictors of death in the next 25 years. After exclusion of 55 men with life threatening diseases (cardiovascular and cancer) and of 161 men because of missing measurements, 1495 men have been analysed for relation between entry factors and subsequent death (n = 670). Twelve factors eventually emerged as powerful predictors of future death: in hierarchical order, age, blood pressure, forced expiratory volume, cigarette smoking, xanthelasma, mother life-status, arm circumference, father life-status, shoulder-pelvis ratio, vital capacity, arcus senilis, and serum cholesterol. Discrimination as provided by logistic modelling placed 19.6% of all cases in the upper decile of the estimated risk, 36.8% in the upper quintile, 2.5% in the lowest decile, and 7.1% in the lowest quintile. Out of those located in the lowest decile of risk, 11.4% died within 25 years while the corresponding percentage in the upper decile was 87.3%. Use of the Cox model yielded slightly better coefficients than logistic function. 相似文献
862.
An enzyme-linked immunosorbent assay for the detection of Entamoeba histolytica antigens in faecal material 总被引:2,自引:0,他引:2
M S Grundy A Voller D Warhurst 《Transactions of the Royal Society of Tropical Medicine and Hygiene》1987,81(4):627-632
This paper describes a method for the detection of Entamoeba histolytica antigens in stool samples using a multi-layer ELISA. The method is sensitive and specific, showing no interference with other intestinal parasites, e.g. E. coli, E. hartmanni, Endolimax nana, Iodamoeba buetschlii, Hymenolepis nana, Giardia lamblia, Trichomonas and Ascaris. The method provides a rapid and simple screening assay for E. histolytica infections and should assist in diagnosis and epidemiological studies of the disease. 相似文献
863.
Effects of danazol on mineral homeostasis in normal postmenopausal women: preliminary communication. 下载免费PDF全文
The effects of danazol on calcium homeostasis in normal postmenopausal women was examined in a 14-day study utilizing a dosage of 800 mg per day. Danazol caused significant falls in plasma ionized calcium and in the fasting urinary calcium/creatinine ratio, indicating inhibition of bone resorption. Retention of phosphate was also observed as expected with this anabolic agent. The plasma total alkaline phosphatase was also depressed by the drug, which had no effect on hepatocellular function as measured by plasma AST. Certain effects induced by treatment with danazol were still apparent two weeks after cessation of treatment. The drug was well tolerated and androgenic side effects were not seen. It is suggested that the minimal dose regimen of danazol which exerts a calcium-sharing effect should be identified, and that this regimen should be considered for use in a prospective study of the effects of danazol on bone mineral content in the postmenopause. 相似文献
864.
865.
866.
K Tanabe K Kageyama S Takada 《Transactions of the Royal Society of Tropical Medicine and Hygiene》1986,80(4):546-548
Mean cell volume and mean cell water content were examined in Plasmodium yoelii-infected mouse erythrocytes by gas chromatography and 3H-sucrose. Mean cell volume increased by 16% in infected erythrocytes with late trophozoites and schizonts. Mean cell water content further increased by 23% in the infected erythrocytes. Measurement of the erythrocyte potassium and sodium concentrations by an atomic absorption spectrophotometer revealed that the infected erythrocytes contained highly elevated sodium and slightly reduced potassium levels when calculated per single erythrocyte. It is suggested that membrane transport processes of sodium and potassium are changed in P. yoelii-infected erythrocytes and that a passive inflow of sodium takes place, which results in an increase in intra-erythrocytic water content. 相似文献
867.
868.
869.
870.
S A Meyer 《American family physician》1986,34(1):159-163
Although jejunoileal bypass surgery proved effective in controlling morbid obesity, the serious adverse effects from the operation were ultimately found to outweigh the benefits. Gastric partitioning results in weight loss by restricting the volume of food ingested rather than by interfering with absorption. Vertical banded gastroplasty has fewer complications than Roux-en-Y gastric bypass and is currently the surgical procedure of choice for morbid obesity. 相似文献