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   1378篇
  免费   109篇
  国内免费   1篇
耳鼻咽喉   2篇
儿科学   34篇
妇产科学   37篇
基础医学   185篇
口腔科学   66篇
临床医学   119篇
内科学   305篇
皮肤病学   58篇
神经病学   145篇
特种医学   86篇
外科学   132篇
综合类   13篇
预防医学   135篇
眼科学   11篇
药学   121篇
中国医学   5篇
肿瘤学   34篇
  2023年   8篇
  2022年   10篇
  2021年   13篇
  2020年   18篇
  2019年   18篇
  2018年   36篇
  2017年   38篇
  2016年   25篇
  2015年   22篇
  2014年   36篇
  2013年   48篇
  2012年   87篇
  2011年   71篇
  2010年   52篇
  2009年   37篇
  2008年   60篇
  2007年   65篇
  2006年   66篇
  2005年   47篇
  2004年   50篇
  2003年   27篇
  2002年   38篇
  2001年   48篇
  2000年   39篇
  1999年   43篇
  1998年   18篇
  1997年   17篇
  1996年   19篇
  1995年   15篇
  1994年   12篇
  1993年   14篇
  1992年   23篇
  1991年   22篇
  1990年   31篇
  1989年   35篇
  1988年   24篇
  1987年   21篇
  1986年   23篇
  1985年   42篇
  1984年   21篇
  1983年   14篇
  1982年   16篇
  1981年   12篇
  1979年   12篇
  1978年   11篇
  1977年   11篇
  1976年   7篇
  1972年   6篇
  1970年   9篇
  1969年   8篇
排序方式: 共有1488条查询结果,搜索用时 265 毫秒
1.
BACKGROUND AND PURPOSE:Endovascular therapy for acute ischemic stroke is often performed with the patient under conscious sedation. Emergent conversion from conscious sedation to general anesthesia is sometimes necessary. The aim of this study was to assess the functional outcome in converted patients compared with patients who remained in conscious sedation and to identify predictors associated with the risk of conversion.MATERIALS AND METHODS:Data from 368 patients, included in 3 trials randomizing between conscious sedation and general anesthesia before endovascular therapy (SIESTA, ANSTROKE, and GOLIATH) constituted the study cohort. Twenty-one (11%) of 185 patients randomized to conscious sedation were emergently converted to general anesthesia.RESULTS:Absence of hyperlipidemia seemed to be the strongest predictor of conversion to general anesthesia, albeit a weak predictor (area under curve = 0.62). Sex, hypertension, diabetes, smoking status, atrial fibrillation, blood pressure, size of the infarct, and level and side of the occlusion were not significantly associated with conversion to general anesthesia. Neither age (mean age, 71.3   ± 13.8 years for conscious sedation versus 71.6  ± 12.3 years for converters, P = .58) nor severity of stroke (mean NIHSS score, 17 ± 4 versus 18 ± 4, respectively, P = .27) were significantly different between converters and those who tolerated conscious sedation. The converters had significantly worse outcome with a common odds ratio of 2.67 (P = .015) for a shift toward a higher mRS score compared with the patients remaining in the conscious sedation group.CONCLUSIONS:Patients undergoing conversion had significantly worse outcome compared with patients remaining in conscious sedation. No factor was identified that predicted conversion from conscious sedation to general anesthesia.

Five studies published in 2015 proved the efficacy of endovascular therapy (EVT) for acute ischemic stroke caused by a large-vessel occlusion.1 However, numerous questions remain regarding how to best deliver this treatment, including evaluation of the optimal thrombectomy technique,2 the most effective method of patient triage,3 or whether EVT should be performed with the patient under either general anesthesia (GA) or conscious sedation (CS).Observational studies have suggested that EVT with the patient under CS is associated with better neurologic outcome and lower mortality compared with GA.4 However, 3 randomized trials reported similar outcomes between CS and GA.5-7 Proposed benefits of CS include stable hemodynamics, clinical monitoring, and a potentially shorter procedure. The disadvantages are an unprotected airway and patient movement, which sometimes may require emergent conversion to GA. Patients who need conversion might be sicker (larger strokes, more medical complications), but the conversion procedure itself may also have a potentially deleterious influence on outcome due to the emergent anesthetic induction, associated hypotension, and added time delay before reperfusion.Although most patients can be treated under the less complex CS, it is of interest to identify factors that can predict the risk of conversion and hence the requirement for GA. We undertook a detailed analysis of the patients who were converted from CS to GA in our individual patient data base from the 3 randomized trials to examine the outcome of the converted patients compared with patients who remained in CS. We also aimed to identify possible predictors associated with a need for GA with EVT.  相似文献   
2.

A key goal for implementation science is the identification of evidence-based consultation protocols and the active ingredients within these protocols that drive clinician behavior change. The current study examined clinicians’ self-coding of fidelity as a potential active ingredient of consultation for the Attachment and Biobehavioral Catch-up (ABC) intervention. It also examined two other potential predictors of clinician fidelity in response to consultation: dosage of consultation and working alliance. Twenty-nine clinicians (97% female, 62% White, M age?=?34 years) participated in a year of weekly fidelity-focused ABC consultation sessions, for which clinicians self-coded fidelity and received consultant feedback on both their coding and their fidelity. Data from the ABC fidelity measure were available for 1067 sessions coded by consultants, and clinicians’ self-coding accuracy was calculated from 1044 sessions coded by both clinicians and consultants. Alliance was measured with the Working Alliance Inventory—Trainee and Supervisor Versions. The study was observational, and fidelity and self-coding accuracy were modeled across time using hierarchical linear modeling. Clinicians’ ABC fidelity, as well as their self-coding accuracy, increased over the course of consultation. Clinicians’ self-coding accuracy predicted their initial fidelity and growth in fidelity. Working alliance was also linked to fidelity and self-coding accuracy. These results suggest that clinician self-coding should be further examined as an active ingredient of consultation. The study has important implications for the design of consultation procedures and fidelity assessments.

  相似文献   
3.
Abstract: The effects of repeated exposure to 20 p.p.m. 4-tert-butyltoIuene (CAS No. [98-51-1]) 6 hr/day for 14 days on the function of the intact nervous system were examined by measurements of flash evoked potentials in Wistar rats. The exposure to 4-tert-butyltoluene induced changes in the amplitudes of the flash evoked potentials. The changes were significantly different from controls on day 2, 19 and 26 after cessation of the exposure, but not on day 5 and 12. No significant difference in body weight gain between groups was found during the experiment. These results indicate that repeated exposure to 20 p.p.m. 4-tert-butyltoluene causes persistent changes in the function of the central nervous system measured as changes in the flash evoked potential. A reevaluation of the present TLV-value of 10 p.p.m. for 4-tert-butyltoluene is suggested.  相似文献   
4.
At two scientific conferences in 1985, one in Copenhagen sponsored by the Nordic Council of Ministers and the World Health Organization (WHO), the other in Raleigh, NC, it was concluded that chronic toxic encephalopathy may develop following long-term occupational exposure to organic solvents (1,2). The terms organic affective syndrome, mild and severe chronic toxic encephalopathy were suggested for this condition describing increasing severity. In May 1990, a conference on organic solvents and the nervous system was held in Copenhagen sponsored by the Commission of the European Communities and the Danish Ministry of the Environment (3). Scientists and representatives from the governments, industries, and labour organisations from the EEC and US participated.  相似文献   
5.
6.
7.
Elderly people (age 75 years; n=48 males and 34 females) were studied in order to elucidate gender differences in elderly subjects on the determinants of muscle power (force and velocity) during a stretch-shortening cycle. All subjects performed three maximal counter-movement vertical jumps using both legs, on a force platform (Kistler 9281 B). The eccentric (Ep) and concentric (Cp) phases of the jumps were analyzed. The Ep was further divided into an acceleration phase (Epacc: from the start of the downward movement to the maximal negative velocity) and deceleration phase (Epdec: from the maximal negative velocity to the end of the downward movement). Jump height for the men was higher than for the women (P < 0.001). During both Epacc and Epdec no significant differences were observed between males and females in force and power generation. However, the men had a higher peak muscle power during the Cp, which may be explained exclusively by the velocity determinant (P < 0.001). No specific gender-related strategy appeared to influence the motor pattern of the movement. The comparable eccentric force generation of the leg extensors in both genders suggests a similar ability to cope with eccentric muscle actions during everyday activities. In contrast, the marked lower capacity for concentric contractions in women may result in an impaired performance, especially in activities where intense and rapid movements are essential, for example when reversing a forward fall. This may be one reason why elderly women are more prone to falls than are elderly men. Accepted: 19 September 2000  相似文献   
8.
CTLA-4 is required for the induction of high dose oral tolerance   总被引:5,自引:3,他引:5  
Mucosal and systemic administrations of high dose antigens induce long- lasting peripheral T cell tolerance. We and others have shown that high dose peripheral T cell tolerance is mediated by anergy or deletion and is preceded by T cell activation. Co-stimulatory molecules B7-1 (CD80)/B7-2 (CD86) and their counter-receptors CD28/CTLA-4 play pivotal roles in T cell activation and immune regulation. In the present study, we examined the roles of the B7 co-stimulation pathway in the generation of high dose peripheral T cell tolerance. We found that blocking B7:CD28/CTLA-4 interaction at the time of tolerance induction partially prevented T cell tolerance, whereas selective blockade of B7:CTLA-4 interaction completely abrogated peripheral T cell tolerance induced by either oral or i.p. antigens. These results suggest that CTLA-4-mediated feedback regulation plays a crucial role in the induction of high dose peripheral T cell tolerance.   相似文献   
9.
10.
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