全文获取类型
收费全文 | 27766篇 |
免费 | 1718篇 |
国内免费 | 71篇 |
专业分类
耳鼻咽喉 | 244篇 |
儿科学 | 617篇 |
妇产科学 | 496篇 |
基础医学 | 3901篇 |
口腔科学 | 642篇 |
临床医学 | 2575篇 |
内科学 | 5318篇 |
皮肤病学 | 475篇 |
神经病学 | 3064篇 |
特种医学 | 1123篇 |
外国民族医学 | 55篇 |
外科学 | 3834篇 |
综合类 | 359篇 |
一般理论 | 10篇 |
预防医学 | 2177篇 |
眼科学 | 784篇 |
药学 | 1920篇 |
中国医学 | 32篇 |
肿瘤学 | 1929篇 |
出版年
2022年 | 195篇 |
2021年 | 385篇 |
2020年 | 231篇 |
2019年 | 380篇 |
2018年 | 432篇 |
2017年 | 359篇 |
2016年 | 397篇 |
2015年 | 538篇 |
2014年 | 716篇 |
2013年 | 1067篇 |
2012年 | 1574篇 |
2011年 | 1631篇 |
2010年 | 894篇 |
2009年 | 833篇 |
2008年 | 1542篇 |
2007年 | 1651篇 |
2006年 | 1580篇 |
2005年 | 1602篇 |
2004年 | 1529篇 |
2003年 | 1434篇 |
2002年 | 1402篇 |
2001年 | 393篇 |
2000年 | 339篇 |
1999年 | 353篇 |
1998年 | 311篇 |
1997年 | 303篇 |
1996年 | 258篇 |
1995年 | 245篇 |
1994年 | 211篇 |
1993年 | 210篇 |
1992年 | 222篇 |
1991年 | 203篇 |
1990年 | 183篇 |
1989年 | 195篇 |
1988年 | 189篇 |
1987年 | 192篇 |
1986年 | 170篇 |
1985年 | 176篇 |
1984年 | 221篇 |
1983年 | 190篇 |
1982年 | 228篇 |
1981年 | 209篇 |
1980年 | 191篇 |
1979年 | 166篇 |
1978年 | 152篇 |
1977年 | 106篇 |
1976年 | 142篇 |
1975年 | 126篇 |
1974年 | 151篇 |
1973年 | 113篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
61.
The effect of hydration water temperature (dip water) on the strength of orthopedic casts is discussed. Three methods of testing are used in an attempt to detect any differences and also to assess their clinical relevance. It was found that warmer water produced stronger casts, however, the differences were not found to be clinically relevant. It is suggested that water temperature be chosen on the basis of considerations other than strength. 相似文献
62.
63.
64.
K H Ladwig W Lehmacher R Roth G Breithardt T Budde M Borggrefe 《Zeitschrift für Kardiologie》1991,80(11):649-656
369 (63%) of 586 consecutive patients with confirmed myocardial infarction were admitted to hospital within 6 h of symptom onset. Patients' arrival to hospital followed a characteristic circadian distribution with a marked morning increase between 0600 and 1200 hours, and a corresponding decrease in the late night hours. There were no differences in the occurrence of late potentials and in ECG data between early and late arrival group. The early group (less than 5.9 h) was, however, characterized by significantly higher cardiac enzyme levels than the late group (greater than 6.0 h); they also experienced more arrhythmic events in the acute phase (16.0% vs. 9.7%; p less than 0.032). Catecholamines were significantly more often necessary (26.4% vs. 10.3%; p less than 0.0001). Six-month prognosis after AMI was markedly worse. The time between symptom onset and hospital arrival was not affected by age and risk factors. In univariate analysis, pain history and recurrent infarction also had no influence on delay of admission to hospital. The time interval was, however, significantly shorter when the acute event occurred during the night (18.4% vs. 8.3%; p less than 0.0001). Absence of prodromi in the prehospital phase (18.5% vs. 12.0%; p less than 0.04) and a higher socio-economic level (68.3% vs. 61.0%; p less than 0.077) also shortened the admission time, whereas a hyperactive behavioral pattern prolonged the delay time (21.1% vs. 28.9%; p less than 0.05). 相似文献
65.
Evaluative composite measurement scales (CMS) are increasingly used in medicine to measure complex constructs in the absence of a reference criterion or ‘gold standard’. However, the level of measurement provided by these instruments has usually been given little attention. This paper explores the influence of the characteristics of the item set and weighting on the level of measurment of an evaluative CMS. The approach is illustrated with an application to the scoring system of the Nottingham Health Profile. Simulations are provided to indicate when the composite score of item responses, on an ordinal or pass—fail scale, could be considered to achieve the properties of an interval scale. 相似文献
66.
A new radiolucent device for increased accuracy of CT-guided fine-needle punctures permits precise determination of the optimum
angle, depth, and position of the fine needle, which can be preset from the data supplied on the CT monitor. Puncture and
repeat scans for controlling the tip of the needle can be performed with the patient in a stationary position. The device
is designed as a belt that holds a needle holder sheath and a goniometric scale, both of which can be moved to varying positions
around the patient. 相似文献
67.
Rafael E. Cuellar MD Walter H. Kaye MD L. K. George Hsu MD Dr. David H. Van Thiel MD 《Digestive diseases and sciences》1988,33(12):1549-1553
Bulimia nervosa is a health problem of increasing magnitude that is estimated to affect 2–5% of the American adolescent and young adult female population. Because of the magnitude of this clinical problem and because of the importance of the upper gastrointestinal tract in its expression, a intradepartmental program of health care for patients affected with the disease was initiated. Eleven consecutive symptomatic bulimic individuals have been evaluated jointly by the gastroenterology and the psychiatry departments of the University of Pittsburgh. Five of these 11 individuals were found to have clinically important upper gastrointestinal pathology including ulcerative esophagitis, erosive gastritis, duodenal ulcer, and delayed gastric emptying. These gastrointestinal conditions could have been either a result of or have contributed to the symptomatology of these five patients. These data suggest that bulimic subjects have clinically important gastroenterological disease processes that require specific diagnosis and treatment independent of the psychiatric treatment provided for the bulimic condition.This work was supported in part by grants from NIDDK AM 32556. 相似文献
68.
Mari-Ann Flyvholm Barbara M. Hall Tove Agner Eva Tiedemann Peter Greenhill Walter Vanderveken Fred E. Freeberg Torkil Menné 《Contact dermatitis》1997,36(1):26-33
Our purpose was to investigate the eliciting threshold concentration of formaldehyde in formaldehyde-sensitive individuals in the occluded and non-occluded patch teat and to evaluate the relationship in repeated open application test (ROAT) with a product containing a formaldehyde releaser. 20 formaldehyde-sensitive patients and a control group of 20 healthy volunteer were included in the study. Occluded and non-occluded patch tests with formaldehyde solutions form 25 to 10,000 ppm. and ROAT for I week with a leave-on cosmetic product containing on average 300 ppm formaldehyde. Were carried out simultaneously on each subject. In the occluded patch test. 1/2 of the 20 patients only reacted to 10,000 ppm formaldehyde. 9 reacted to 5,000 ppm. 3 reacted to 1.000 ppm. 2 reacted to 500 ppm and I reacted to 25 ppm. No definite positive reactions were observed in the non-occluded patch test or in the ROAT No positive reactions were observed in the control group to any of the test procedures. We concluded that the threshold concentration for occluded patch test to formaldehyde in formaldehyde-sensitive patients was 250 ppm. The threshold in occluded patch test corresponded to the degree of sensitivity Definite positive reactions in the ROAT were not seen, either indicating that they are unlikely to happen with the type of product used or that the exposure time was too short. 相似文献
69.
Munzel Peter; Bock-Hennig Barbara; Schieback Sylvia; Gschaidmeier Harald; Beck-Gschaidmeier Simone; Bock Karl Walter 《Carcinogenesis》1996,17(2):197-202
Modulation of DNA synthesis by 2,3,7,8-tetrachlorodi-benzo-p-dioxin(TCDD) was studied in primary cultures of hepatocytes and inrat liver epithelial cells (WB-F344) to develop models for studieson the interactions between the activated Ah receptor and cellulargrowth control. In hepatocytes TCDD either positively or negativelymodulated EGF-stimulated DNA synthesis. In the presence of ethlnylestradiol1012 M TCDD moderately increased EGF-stimulated DNA synthyesis( 相似文献
70.