首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2448055篇
  免费   172266篇
  国内免费   4811篇
耳鼻咽喉   33008篇
儿科学   80050篇
妇产科学   66987篇
基础医学   348780篇
口腔科学   70918篇
临床医学   221178篇
内科学   469564篇
皮肤病学   55725篇
神经病学   189560篇
特种医学   93416篇
外国民族医学   437篇
外科学   369567篇
综合类   53880篇
现状与发展   5篇
一般理论   757篇
预防医学   179903篇
眼科学   57934篇
药学   184957篇
  13篇
中国医学   6180篇
肿瘤学   142313篇
  2021年   18324篇
  2019年   18979篇
  2018年   27541篇
  2017年   21157篇
  2016年   23513篇
  2015年   26609篇
  2014年   36722篇
  2013年   53778篇
  2012年   74140篇
  2011年   78144篇
  2010年   46340篇
  2009年   43302篇
  2008年   72399篇
  2007年   77277篇
  2006年   77924篇
  2005年   74482篇
  2004年   71637篇
  2003年   68437篇
  2002年   65893篇
  2001年   127880篇
  2000年   130888篇
  1999年   108550篇
  1998年   28395篇
  1997年   24844篇
  1996年   24928篇
  1995年   23820篇
  1994年   21745篇
  1993年   20320篇
  1992年   81984篇
  1991年   79074篇
  1990年   76853篇
  1989年   73762篇
  1988年   67052篇
  1987年   65331篇
  1986年   61751篇
  1985年   58523篇
  1984年   42854篇
  1983年   36479篇
  1982年   20482篇
  1979年   38162篇
  1978年   26240篇
  1977年   22828篇
  1976年   20710篇
  1975年   22520篇
  1974年   26907篇
  1973年   25929篇
  1972年   24216篇
  1971年   22606篇
  1970年   20904篇
  1969年   19769篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
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   
993.
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   
994.
Supplementation of the diet of adult male rats with 4,000 ppm zinc as ZnSO4 for 30 to 32 days increased the zinc content in the testis and sperm by 25 and 18 per cent respectively, but did not change the same in accessory reproductive tissues, e.g. epididymis, seminal vesicle and prostate. The incidence of conception from mating between normal females and zinc fed males was lower as compared to mating between normal females and control males. This observation indicated reduced fertility of the males resulting from additional zinc ingestion. Motility of the sperm collected from the epididymis (tail) of the zinc treated rats was found to be inhibited. It has been suggested that excess zinc in the sperm was responsible for their poor motility and hence a reduced fertilising capacity.  相似文献   
995.
996.
Others have reported that spinal cord transection non-uniformly affects the activities of the cardiac, renal and splenic nerves. We were unable to confirm this finding while recording the wide band (1-1000 Hz) discharges of these sympathetic nerves in baroreceptor-denervated, chloralose-anesthetized cats. Most of the power in nerve discharges was below 6 Hz. There was high coherence between the low frequency discharges of different nerves, and power below 15 Hz was essentially eliminated by spinal transection. Evidence is presented that the disparities between this and past studies are, in part, due to the use of a 30-Hz high-pass filter in the earlier studies.  相似文献   
997.
998.
The Executive Nurse Council was challenged to develop strategies designed to empower staff nurses and nurse managers and create opportunities for professional growth. Implementation of these strategies resulted in broad-sweeping changes in roles and functions of groups and individuals at all levels of the organization. The authors describe a support role, administrative nurse specialist, designed to support staff and managers striving to actualize changes in a shared governance framework.  相似文献   
999.
1000.
Coexistent primary hyperparathyroidism and monoclonal gammopathy, although rare, has been reported previously by a number of investigators. We report four patients with such an occurrence who were seen between 1976 and 1988. Another patient with primary hyperparathyroidism also had multiple myeloma and was in remission for 12 years. These patients represent approximately 1% of the 386 patients with primary hyperparathyroidism seen during the same 12-year period. Although several mechanisms have been proposed to explain this concurrence, we believe it is the result of a chance occurrence. A review of the literature, an estimate of the chance occurrence of coincidental monoclonal gammopathy, benign or malignant, in patients with primary hyperparathyroidism, and some practical implications of this interesting coexistence are presented.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号