全文获取类型
收费全文 | 2230638篇 |
免费 | 181802篇 |
国内免费 | 4127篇 |
专业分类
耳鼻咽喉 | 31687篇 |
儿科学 | 71020篇 |
妇产科学 | 64528篇 |
基础医学 | 318840篇 |
口腔科学 | 66314篇 |
临床医学 | 197021篇 |
内科学 | 430831篇 |
皮肤病学 | 47062篇 |
神经病学 | 181484篇 |
特种医学 | 89618篇 |
外国民族医学 | 632篇 |
外科学 | 341537篇 |
综合类 | 58593篇 |
现状与发展 | 5篇 |
一般理论 | 766篇 |
预防医学 | 174196篇 |
眼科学 | 52297篇 |
药学 | 168183篇 |
3篇 | |
中国医学 | 4257篇 |
肿瘤学 | 117693篇 |
出版年
2018年 | 20487篇 |
2015年 | 20980篇 |
2014年 | 29255篇 |
2013年 | 44683篇 |
2012年 | 60299篇 |
2011年 | 63516篇 |
2010年 | 37408篇 |
2009年 | 35544篇 |
2008年 | 60527篇 |
2007年 | 64643篇 |
2006年 | 65090篇 |
2005年 | 63547篇 |
2004年 | 62541篇 |
2003年 | 59941篇 |
2002年 | 58397篇 |
2001年 | 99562篇 |
2000年 | 102572篇 |
1999年 | 87125篇 |
1998年 | 24695篇 |
1997年 | 22590篇 |
1996年 | 22455篇 |
1995年 | 21679篇 |
1994年 | 20482篇 |
1993年 | 19263篇 |
1992年 | 72660篇 |
1991年 | 70579篇 |
1990年 | 69098篇 |
1989年 | 66752篇 |
1988年 | 62454篇 |
1987年 | 61459篇 |
1986年 | 58460篇 |
1985年 | 56574篇 |
1984年 | 42904篇 |
1983年 | 36898篇 |
1982年 | 22500篇 |
1981年 | 20313篇 |
1980年 | 18976篇 |
1979年 | 41982篇 |
1978年 | 29632篇 |
1977年 | 24958篇 |
1976年 | 23289篇 |
1975年 | 24848篇 |
1974年 | 30638篇 |
1973年 | 29383篇 |
1972年 | 27282篇 |
1971年 | 25708篇 |
1970年 | 23874篇 |
1969年 | 22735篇 |
1968年 | 20641篇 |
1967年 | 18846篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
921.
P Tugwell L Hart G Kraag A Park C Dok F Bianchi C Goldsmith W W Buchanan 《The Journal of rheumatology》1984,11(4):457-461
A crossover double-blind controlled trial was performed on 36 patients with rheumatoid arthritis to assess the necessity for serum salicylate monitoring in determining optimal dosage. There was no clinically or statistically significant increase in the clinical improvement of patients associated with serum monitoring but potentially toxic serum levels occurred without tinnitus when serum monitoring was not used. 相似文献
922.
923.
924.
925.
K Mahmood M N Chowdhury E A Ayoola I A Mofleh R S Rashed F Z Faleh 《Tropical gastroenterology》1991,12(4):188-191
Seventy seven antral biopsies were collected from patients attending endoscopy clinic at King Khalid University Hospital, Riyadh, Saudi Arabia during a period of six months between December 1988 to May 1989. Of these 69 (89.6%) showed chronic gastritis as well as Helicobacter-like organisms (HLOs) in the biopsy specimens while 63 (81.8%) of biopsies grew Helicobacter pylori on culture. These findings indicate a good correlation between the histological diagnosis of chronic gastritis and isolation of H. pylori on culture. 相似文献
926.
Spontaneous neuronal hyperactivity in the medial and intralaminar thalamic nuclei of patients with deafferentation pain 总被引:6,自引:0,他引:6
Electrical activity was recorded from single cells in the thalamus of 10 patients with chronic pain associated with deafferentation. Under local anesthesia, these patients underwent either electrode implantation or thalamotomy for treatment of their pain. In eight of the 10 patients, single units were identified as discharging spontaneously in high-frequency, often rhythmic, bursts. The discharges were of two types: short bursts comprised of two to six spikes with a burst frequency of one to four per second; and long trains of 30 to 80 spikes of similar frequency. Reconstruction of electrode trajectories indicated that recordings were made from the region corresponding to the lateral aspect of the mediodorsal thalamic nucleus, the central lateral nucleus, a small part of the central median nucleus, and the parafascicular nucleus. In the eight patients in whom spontaneous neuronal burst activity was exhibited, it was impossible to study activity evoked by natural cutaneous stimulation due to the continuous spontaneous neuronal discharges. Both animal and human studies have suggested that pain related to deafferentation is accompanied by spontaneous hyperactivity in the dorsal horn of the spinal cord and in the ventral posterior thalamic nuclei. The authors present evidence of spontaneous neuronal hyperactivity in the intralaminar thalamic nuclei of patients with pain related to deafferentation. The findings suggest that spontaneous neuronal discharge in patients with pain related to deafferentation is more widespread in the central nervous system than has been previously appreciated. The results have important implications for the surgical treatment of chronic pain. 相似文献
927.
We sought to determine whether there are indirect costs of teaching in Canadian hospitals. To examine cost differences between teaching and nonteaching hospitals we estimated two cost functions: cost per case and cost per patient-day (dependent variables). The independent variables were number of beds, occupancy rate, teaching ratio (number of residents and interns per 100 beds), province, urbanicity (the population density of the county in which the hospital was situated) and wage index. Within each hospital we categorized a random sample of patient discharges according to case mix and severity of illness using age and standard diagnosis and procedure codes. Teaching ratio and case severity were each highly correlated positively with the dependent variables. The other variables that led to higher costs in teaching hospitals were wage rates and number of beds. Our regression model could serve as the basis of a reimbursement system, adjusted for severity and teaching status, particularly in provinces moving toward introducing case-weighting mechanisms into their payment model. Even if teaching hospitals were paid more than nonteaching hospitals because of the difference in the severity of illness there should be an additional allowance to cover the indirect costs of teaching. 相似文献
928.
M H Eijgelshoven E R De Kloet D T Van den Berg P L Van Giersbergen 《European journal of pharmacology》1991,205(2):183-189
Evidence indicates that endogenous opioid peptides and glucocorticoids participate in the control of cardiovascular regulation during hemorrhagic shock. In the present study, we investigated a possible interaction between brain opioid peptides and adrenal corticosteroids regarding the control of arterial pressure during hemorrhage. The bleeding volumes required to lower arterial pressure to 80, 60 and 40 mmHg were studied in anesthetized sham-operated (SHAM) and adrenalectomized (ADX) rats. I.c.v. administration of 10 micrograms of naloxone resulted in a significant increase in the bleeding volume required to lower arterial pressure from 60 to 40 mmHg in SHAM animals, whereas no effect of naloxone was observed in ADX animals. Replacement therapy with a 100% corticosterone pellet (100 mg, s.c.), but not with a 12.5% corticosterone pellet (12.5 mg corticosterone and 87.5 mg cholesterol, s.c.), resulted in an effect of naloxone on the bleeding volume in ADX animals. The effect of replacement therapy could be inhibited by i.c.v. pretreatment with the synthetic glucocorticoid receptor antagonist, RU38486 (100 ng). These data suggest that (1) opioid mechanisms are involved in the regulation of blood pressure during hemorrhage, and (2) occupancy of glucocorticoid receptors is required for naloxone to exert its hemodynamic effect during hemorrhagic hypotension in ADX rats. 相似文献
929.
Between May 1984 and January 1988, 18 patients (31 pyeloureteral units) with documented symptomatic cystine stones were treated. Stone size ranged from 5 to 56 mm. in largest diameter, with an average of 21 mm. All pyeloureteral units were treated initially by endourological methods, including ureteroscopy in 10, percutaneous ultrasonic lithotripsy in 9, extracorporeal shock wave lithotripsy (ESWL) in 10 and chemolysis in 2. Of the patients 10 required a combination of these technologies and 2 required an open operation. Of the 31 units 23 were free of stones when the patient was discharged from the hospital. Of 8 patients with retained stones only 3 had fragments greater than 3 mm. in diameter. Based on this experience an algorithm was developed for the urological management of cystine stones. Ureteral calculi may be removed by ureteroscopic techniques or manipulated into the renal pelvis and managed as renal stones. Cystine renal calculi of less than 1.5 cm. may be treated with ESWL monotherapy. Stones of 1.5 to 3 cm. may be treated with ESWL and dissolution, or percutaneous ultrasonic lithotripsy plus dissolution. Staghorn calculi may be treated by percutaneous ultrasonic lithotripsy plus ESWL and/or dissolution for retained fragments. 相似文献
930.