全文获取类型
收费全文 | 2460194篇 |
免费 | 172960篇 |
国内免费 | 4851篇 |
专业分类
耳鼻咽喉 | 33202篇 |
儿科学 | 80298篇 |
妇产科学 | 67278篇 |
基础医学 | 350284篇 |
口腔科学 | 71800篇 |
临床医学 | 222111篇 |
内科学 | 472180篇 |
皮肤病学 | 56015篇 |
神经病学 | 190537篇 |
特种医学 | 93659篇 |
外国民族医学 | 438篇 |
外科学 | 370935篇 |
综合类 | 53967篇 |
现状与发展 | 5篇 |
一般理论 | 762篇 |
预防医学 | 181189篇 |
眼科学 | 58147篇 |
药学 | 186011篇 |
13篇 | |
中国医学 | 6246篇 |
肿瘤学 | 142928篇 |
出版年
2021年 | 18774篇 |
2019年 | 19310篇 |
2018年 | 27968篇 |
2017年 | 21453篇 |
2016年 | 23831篇 |
2015年 | 27001篇 |
2014年 | 37191篇 |
2013年 | 54455篇 |
2012年 | 74983篇 |
2011年 | 79073篇 |
2010年 | 46847篇 |
2009年 | 43730篇 |
2008年 | 73077篇 |
2007年 | 77927篇 |
2006年 | 78518篇 |
2005年 | 75026篇 |
2004年 | 72104篇 |
2003年 | 68876篇 |
2002年 | 66260篇 |
2001年 | 128105篇 |
2000年 | 131105篇 |
1999年 | 108722篇 |
1998年 | 28483篇 |
1997年 | 24906篇 |
1996年 | 24993篇 |
1995年 | 23878篇 |
1994年 | 21787篇 |
1993年 | 20361篇 |
1992年 | 82120篇 |
1991年 | 79188篇 |
1990年 | 76967篇 |
1989年 | 73852篇 |
1988年 | 67150篇 |
1987年 | 65402篇 |
1986年 | 61822篇 |
1985年 | 58597篇 |
1984年 | 42914篇 |
1983年 | 36527篇 |
1982年 | 20518篇 |
1979年 | 38232篇 |
1978年 | 26266篇 |
1977年 | 22863篇 |
1976年 | 20742篇 |
1975年 | 22565篇 |
1974年 | 26944篇 |
1973年 | 25965篇 |
1972年 | 24240篇 |
1971年 | 22630篇 |
1970年 | 20924篇 |
1969年 | 19790篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
992.
993.
994.
The overall goal of this paper is to provide for the first time a comprehensive critical review of the literature on contraceptive failure in developed countries, primarily the United States. The first two sections of our paper lay the groundwork for a critical assessment of the extensive body of studies on this subject, by systematically exploring the concepts and measurement of contraceptive efficacy and the methodological pitfalls that snare many investigators and compromise their results. The next two sections focus on results in the literature. First we provide a method-by-method critique of the available studies and then we summarize our conclusions in a single table that provides efficacy information necessary for women and couples to make an informed choice of a method of contraception. We close with a set of substantive observations and also a set of methodological recommendations intended to improve the quality and comparability of findings from future research. 相似文献
995.
Application of thiamine (1 X 10(-11)-1 X 10(-3) mol/l) on the membrane of cochlear round window increased the amplitude and decreased the latency of the auditory nerve action potential, waves I and II of brainstem auditory-evoked electrical potentials in response to acoustic clicks of different intensity. The mechanism of thiamine action on auditory-evoked electric potentials is discussed. 相似文献
996.
Two million burns occur annually in the USA, of which 95% aretreated in an out-patient setting. The treatment of burns iscontroversial. There are few data from controlled studies toprovide rational guidelines for the frequency of both dressingchanges and patient visits for the physician. Conclusions concerninginfection drawn from studies on major burns are misleading whenapplied to the management of minor burns. Trauma to regeneratingepithelium caused by frequent dressing change is of relativelyless importance in treating major burns, because the controlof infection is of overriding importance. In the treatment ofminor burns, the traumatic consequences of too frequent changesof dressing may assume greater importance. There is a clearneed to study the variables in the treatment of minor burnsand to generate criteria for their clinical management thatare distinct from those of major burn management. Collaborativestudies of out-patient populations by providers of primary healthcare are suggested as a useful approach to such investigation.The effects of several additional therapies are reviewed, includinginitial cold therapy, debridement of blisters and antibiotics. 相似文献
997.
998.
999.
We examined several possible causes for the high incidence of poor sensory acuity in the limbs of 176 patients with moderate to severe peripheral vascular insufficiency. We investigated the relationships of diabetes, alcoholism, and smoking, as well as the severity of peripheral vascular disease, to the integrity of basic sensory modalities such as two-point discrimination and perception of light touch. The presence or absence of diabetes exerted the strongest effect on peripheral sensation. In patients who did not have diabetes, sensation in the limbs was most strongly affected by whether the patient was an alcoholic. Smoking did not have a significant effect on limb sensation. Among nondiabetic, nonalcoholic patients, there was a weak residual effect related to the severity of the peripheral vascular insufficiency. Even among these patients, however, systemic factors predominated in determining the loss of sensation. We also examined the extent to which loss of sensation might be related to the development of ulcers. Among patients who were not diabetic, there was a highly significant relationship between loss of sensation and the presence of limb ulceration. Surprisingly, however, there was no discernable relationship between the presence of ulcers in diabetic patients and the degree of loss of peripheral sensation. This result suggests that a large percentage of ulcers seen in diabetic patients are not of neurogenic origin. 相似文献
1000.
Work therapy and return to work 总被引:2,自引:0,他引:2
In summary, data were selected for 1 year on patients treated in the Work Tolerance Program at the Hand Rehabilitation Center in Philadelphia. The type of information obtained has been used to obtain a profile of the patient population in the Work Tolerance Program. Statistical analysis was used, not only to formulate patient demographics, but also to evaluate the length of treatment of patients in the Work Tolerance Program. This period averaged 6 weeks. The statistical analysis also revealed there was significant interaction between the type of injury and the patient's diagnosis, and the rate of return to work. The patients with injuries to bone and nerve required longer periods of treatment until they returned to work than did patients with injuries to soft tissue or combination injuries. Our statistical analysis revealed that in 1982, 75 per cent of the patients in the Work Tolerance Program returned to work to regular or modified jobs. The length of time from injury to return to work was 63 per cent longer for patients with Workers' Compensation coverage than for patients with private insurance coverage. Because the statistical analysis that 60 per cent of the patients treated in the Work Tolerance Program were Workers' Compensation insured, and 80 per cent of the patients treated in the Work Tolerance Program were secondarily referred, it should be recognized that all patients with severe hand injuries would benefit from an immediate referral to a Hand Rehabilitation Center of excellence to facilitate their therapeutic management and expedite their recovery from time of injury to return to work. This study was restricted to the analysis of length of treatment and rate of return to work. Future studies should study the effect of early referral and the application of specific treatments. 相似文献