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   49534篇
  免费   4009篇
  国内免费   133篇
耳鼻咽喉   617篇
儿科学   1292篇
妇产科学   1123篇
基础医学   6639篇
口腔科学   947篇
临床医学   5656篇
内科学   9799篇
皮肤病学   502篇
神经病学   4097篇
特种医学   1649篇
外科学   7896篇
综合类   797篇
现状与发展   1篇
一般理论   38篇
预防医学   4746篇
眼科学   824篇
药学   3375篇
中国医学   78篇
肿瘤学   3600篇
  2023年   324篇
  2022年   392篇
  2021年   1330篇
  2020年   720篇
  2019年   1159篇
  2018年   1313篇
  2017年   938篇
  2016年   948篇
  2015年   1103篇
  2014年   1509篇
  2013年   2029篇
  2012年   3145篇
  2011年   3160篇
  2010年   1701篇
  2009年   1485篇
  2008年   2606篇
  2007年   2664篇
  2006年   2396篇
  2005年   2336篇
  2004年   2310篇
  2003年   2130篇
  2002年   2066篇
  2001年   1045篇
  2000年   1006篇
  1999年   932篇
  1998年   601篇
  1997年   532篇
  1996年   474篇
  1995年   461篇
  1994年   368篇
  1993年   311篇
  1992年   713篇
  1991年   593篇
  1990年   601篇
  1989年   556篇
  1988年   547篇
  1987年   517篇
  1986年   539篇
  1985年   516篇
  1984年   453篇
  1983年   379篇
  1982年   293篇
  1981年   272篇
  1980年   294篇
  1979年   395篇
  1978年   291篇
  1977年   266篇
  1974年   260篇
  1973年   237篇
  1972年   225篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
71.
Fibromyalgia (FM) is a chronic, potentially disabling, cluster of symptoms that manifests as pain for 3 months or more and pain with pressure on 11 of 18 tender points throughout the body. Because there is no known cause, and therefore, no cure, treatment focuses on the control or relief of symptoms. Many patients are referred to rehabilitation settings for physical or exercise therapy. While exercise is helpful in the control of the pain, stiffness, fatigue, sleep disorders, and mood changes, a holistic approach to treatment is more effective. Rehabilitation nurses provide major support for patients with FM. Validation of the patients' experiences is essential for achieving quality of life. Many patients have a history of being undertreated because of a lack of credibility and invisibility of the illness. This article provides background information about FM, summarizes the FM trajectory, reviews approaches to management, and discusses the role of rehabilitation nurses in a holistic approach to care of clients with FM.  相似文献   
72.
73.
An immunofluorescent (IF) method that detects Burkholderia pseudomallei in clinical specimens within 10 min was devised. The results of this rapid method and those of an existing IF method were prospectively compared with the culture results for 776 specimens from patients with suspected melioidosis. The sensitivities of both IF tests were 66%, and the specificities were 99.5 and 99.4%, respectively.  相似文献   
74.
OBJECTIVE: Avoidance of potential iatrogenic nerve injury during insertion of Ilizarov fine wires into areas of high anatomic risk by using a modified nerve stimulation technique. INDICATIONS: Application of the Ilizarov ring fixator to areas of high anatomic hazard, in situations where anatomic topography may be distorted by previous surgery, trauma, or congenital anomalies. CONTRAINDICATIONS: Use of systemic muscle relaxants. Caution in patient with cardiac pacemaker. SURGICAL TECHNIQUE: Preliminary experiments showed that a standard nerve-stimulating device can deliver a negatively charged, monophasic square pulse of current through Ilizarov wires. During the application of an Ilizarov frame to potentially hazardous anatomic regions, providing no systemic muscle relaxants are used, a voltage field sufficient to cause nerves in close proximity to the Ilizarov wire to depolarize is produced. Identification of a distal muscle twitch provoked by the stimulation may indicate a potential for iatrogenic nerve injury. RESULTS: Results show that with the nerve stimulator set at 2.5 mA (pulsed at a frequency of 2 Hz), peripheral nerves are stimulated if they lie within 5 mm of the wires. Should a distal muscle twitch occur, wires should be repositioned so that equivalent stimulation produces no twitch. The technique was used during Ilizarov frame application in ten patients, with only a single occurrence of distal muscle twitches in a lower-leg frame. Following repositioning of the Ilizarov wire in this case, no further twitches were observed, indicating that no Ilizarov wire was inserted close to peripheral nerves. No neurologic impairment was present postoperatively.  相似文献   
75.
76.
77.
Using fura-2 loaded neural tumour cells, SK-N-SH, we demonstrate that receptor-mediated activation of phosphoinositide hydrolysis not only causes the release of Ca2+ from intracellular stores but also causes a concomitant influx of extracellular Ca2+. Thapsigargin (TG), a sesquiterpene lactone, causes a sustained elevation of intracellular Ca2+ and depletion of the inositol 1, 4, 5-trisphosphate-sensitive intracellular Ca2+ stores. In the absence of extracellular Ca2+, the increase in intracellular Ca2+ concentration ([Ca2+]i) was transient, suggesting that thapsigargin activates both intracellular mobilization and the influx of Ca2+ from extracellular space. These results are consistent with the proposal that the depletion of the inositol 1, 4, 5-trisphosphate-sensitive intracellular Ca2+ pool serves as a signal for Ca2+ influx.  相似文献   
78.
The purpose of the present study was to characterize the metabolism of dopamine (DA) in tuberoinfundibular (TI) neurons terminating in the median eminence and to examine the effects of procedures that alter the synthesis and turnover of DA in these neurons on the concentrations of dihydroxyphenylacetic acid (DOPAC) in the median eminence. The DA uptake inhibitor nomifensine (25 mg/kg, i.p.; 30 min) failed to alter median eminence DOPAC concentrations indicating that very little released DA is recaptured and metabolized by TIDA neurons. Within 5 min following the administration of the monoamine oxidase inhibitor pargyline (50 mg/kg, i.v.) median eminence DOPAC concentrations declined to 15% of control demonstrating that this metabolite has a high turnover rate and is rapidly removed from the median eminence. Median eminence DOPAC concentrations in diestrous female rats, whose TIDA neuronal activity is higher than in the male, were two-fold greater than in male rats. Prolactin (10 micrograms/rat, i.c.v.; 12 h), which increases TIDA neuronal activity, produced a corresponding increase in median eminence DOPAC concentrations in male rats. Restraint stress (30 min), which decreases TIDA neuronal activity, produced a corresponding decrease in median eminence DOPAC concentrations in diestrous female rats. The results from the present study suggest that DOPAC concentrations in the median eminence can be used as an index of TIDA neuronal activity.  相似文献   
79.
The sera from 660 healthy blood donors from Canberra were tested for antibodies to Toxocara canis by the ELISA test. The results were compared with those from patients with suspected or confirmed visceral larva migrans or ocular toxocariasis. Over 7% of Canberra sera showed elevated levels of antibody reacting with T. canis antigen. Sera from patients resident in Australia with other helminth parasites did not cross-react with T. canis antigen in our tests. However, studies of sera collected in several tropical countries with other parasitic infection, show that cross-reactions with other parasites are possible. The use of purified glycoprotein antigen does not alter the possibility of cross-reaction. Observations and experiments show that people in Canberra may be exposed to the infective eggs of T. canis.  相似文献   
80.
Experience with intraaortic balloon counterpulsation   总被引:6,自引:0,他引:6  
An eleven-year experience with intraaortic balloon pumping (IABP) or counterpulsation in 637 patients was analyzed with respect to early and late results. Intraaortic balloon pumping was employed for left ventricular pump failure, for coronary insufficiency, and in association with cardiac operations. Late results were analyzed by follow-up of 283 (93%) of the 304 patients leaving the hospital, and were studied with respect to duration of survival, activity status, occupational status, presence of cardiac symptoms, use of cardiac medications, and presence of lower extremity claudication. Early results were analyzed for hospital survival (304/637 [48%]). Patient complications of IABP included wound infection (1/637 or 0.2%), vascular complications (66/637 or 10.4%), and balloon failure (8/637 or 1.3%). No deaths were attributable to complications of IABP. Survival did not correlate with the duration of IABP. Survival was improved in patients who had revascularization in association with IABP.  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