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   1930篇
  免费   652篇
  国内免费   42篇
耳鼻咽喉   57篇
儿科学   75篇
妇产科学   24篇
基础医学   42篇
口腔科学   28篇
临床医学   339篇
内科学   554篇
皮肤病学   73篇
神经病学   145篇
特种医学   57篇
外科学   727篇
综合类   9篇
预防医学   170篇
眼科学   125篇
药学   49篇
中国医学   5篇
肿瘤学   145篇
  2024年   17篇
  2023年   204篇
  2022年   35篇
  2021年   90篇
  2020年   103篇
  2019年   46篇
  2018年   182篇
  2017年   180篇
  2016年   166篇
  2015年   160篇
  2014年   208篇
  2013年   210篇
  2012年   87篇
  2011年   80篇
  2010年   154篇
  2009年   195篇
  2008年   70篇
  2007年   33篇
  2006年   66篇
  2005年   43篇
  2004年   23篇
  2003年   13篇
  2002年   17篇
  2001年   25篇
  2000年   13篇
  1999年   27篇
  1998年   28篇
  1997年   26篇
  1996年   25篇
  1995年   24篇
  1994年   12篇
  1993年   11篇
  1992年   10篇
  1991年   8篇
  1990年   5篇
  1989年   3篇
  1988年   3篇
  1987年   5篇
  1986年   2篇
  1985年   1篇
  1984年   1篇
  1983年   1篇
  1982年   1篇
  1981年   4篇
  1980年   2篇
  1974年   2篇
  1973年   1篇
  1969年   1篇
  1962年   1篇
排序方式: 共有2624条查询结果,搜索用时 15 毫秒
1.
2.
3.
A case of preeclampsia complicated by serous retinal detachment is described. The anaesthetic implications are discussed.  相似文献   
4.
The concept of need and the practice of needs assessment are both subject to a wide range of interpretations, to the likely detriment of individual assessments and to multidisciplinary working. Clear definition is important for individual assessment, for the development of multidisciplinary tools and in gathering planning information. The concept of need is clarified, firstly by distinguishing between need and the difficulties that engender it, and secondly through a taxonomy of need. These assist clear definitions of both need and needs assessment when linked with a consideration of the current help a person receives and a specification of the type of help required by a person to meet their needs. Such definitions have implications for the role of needs assessment in individual assessment, service evaluation, service management and planning and in the development of multidisciplinary needs assessment tools.  相似文献   
5.
EDITORIAL COMMENT: We accepted these case reports for publication not only to remind readers that a classical Caesarean scar is more likely than a lower uterine segment scar to rupture or dehisce, but also to stress that women should be counselled appropriately when classical Caesarean section has been performed. Our Australian population is also mobile and women may not return to the same institution or obstetrician for their next confinement. Tracing the details of a previous delivery from another hospital or practitioner even in the same community should be a routine enquiry when a patient has had a Caesarean section in a previous pregnancy but the required information is often difficult to obtain. The woman herse(fis the essential repository for this information. It should also be noted that the recent increase in the number of Caesarean sections performed for fetal indications before 30 weeks' gestation has resulted in more vertical incisions because of a poorly formed lower uterine segment.  相似文献   
6.
The efficiency and side-effects of tiaprofenic acid, mefenamic acid and placebo were compared in the treatment of primary dysmenorrhoea. The trial was a double-blind prospective randomized 3-way crossover study during 6 successive menstrual cycles following a 2-cycle run-in period and involved 50 women with primary dysmenorrhoea selected from 96 volunteers between 16 and 35 years of age. Overall pain was significantly less (p less than 0.05) on treatment with tiaprofenic acid than on treatment with mefanemic acid, placebo, or the women's usual treatments. Both active treatments were well tolerated but more side-effects were reported during treatment with mefenamic acid.  相似文献   
7.
BACKGROUND: Multiple modalities are available for treating acne scars, one of which is chemical peeling. OBJECTIVE: To evaluate the efficacy of medium-depth peels in the treatment of acne scars. METHODS: A total of 15 patients (14 women and 1 man) were seen between November 1998 and March 2000. A medium-depth chemical peel was performed. The peel was performed using a combination of Jessner's solution followed by the application of 35% trichloroacetic acid (TCA). The mean age of patients who entered the study was 28 years. A total of 42 peeling sessions were performed: 13 patients had the full three-session regiment, 1 patient had two sessions, and 1 had only one session. RESULTS: Patients in our study had two forms of acne scars, the atrophic saucer or crater-like form and the pitted (ice-pick) form. Improvement occurred in all except one of our patients. Significant improvement (greater than 75% clearance of lesions) occurred in 1 patient (6.6%), moderate improvement (51-75% clearance) in 8 patients (53.3%), mild improvement (26-50% clearance) in 4 patients (26.6%), minimal improvement (1-25% clearance) in 1 patient (6.6%), and no response in 1 patient (6.6%). All patients had different combinations of the above two forms. Four patients (26.6%) had mainly pitted scars and deep atrophic scars. The clinical response in those patients was moderate, mild, minimal, and no response, respectively. The remainder of our patients had mainly atrophic scars of moderate depth. Nine patients (73.4%) suffered from transient postinflammatory hyperpigmentation. In two of them it was preceded by erythema that lasted for more than 1 month. All patients were free of noticeable pigmentation 3 months after the final peel. Patients in whom hyperpigmentation did not develop were of light brown complexion. CONCLUSION: We conclude that medium-depth chemical peel is a safe and effective method of treating acne scars even in patients with dark complexion.  相似文献   
8.
9.
Modified ultrafiltration after cardiopulmonary bypass in children has been shown to be associated with an increase in arterial blood pressure. As part of a series of studies to investigate the possible causes of this blood pressure elevation, the hypothesis that if filtration was removing a significant amount of fentanyl, then the increase in blood pressure might be due to pain was proposed. Ten children, aged between 0.5 and 9.3 years (median 3.8 years), weighing 5.9 to 25..5 kg (median 15.7 kg), underwent corrective cardiac surgery (incorporating modified ultrafiltration). A standard anesthetic protocol was followed, with up to 78 μg/kg of fentanyl given prebypass for analgesia. After completion of cardiopulmonary bypass, modified ultrafiltration was commenced at 100 mL/min until a hematocrit of 35% was reached. Samples were taken of arterial blood (prefiltration, 3, 10, and 20 minutes postfiltration), the venous reservoir blood (prefiltration) and the filtrate (5 and 10 minutes into filtration). Hemodynamic data were recorded both prefiltration and postfiltration. The hemodynamic data showed the expected rise in both systemic arterial pressure and cardiac index after ultrafiltration. The plasma fentanyl concentrations did not significantly change after ultrafiltration: 1.59 to 12.39 ng/mL (median 6.27 ng/mL) prefiltration and 2.05 to 15.59 ng/mL (6.29 ng/mL) at 3 minutes, 2.22 to 12.64 ng/mL (6.87 ng/mL) at 10 minutes, and 1.83 to 11.52 ng/mL (5.85 ng/mL) at 20 minutes postfiltration. The concentration of fentanyl in the venous reservoir, 2.06 to 11.64 ng/mL (7.04 ng/mL), was not significantly different from the plasma levels. The level of fentanyl in the filtrate was significantly less than the plasma levels, 0.243 to 1.87 ng/mL (0.894 ng/mL) at 5 minutes and 0.385 to 1.688 ng / mL (0.952 ng / mL) at 10 minutes into filtration; (P < 0.02 by the Wilcoxon signed-rank method). The data show that the plasma fentanyl concentration was not significantly reduced by modified ultrafiltration. The fentanyl levels found prefiltration were maintained postfiltration, and the observed changes in systemic arterial pressure were not due to an acute fall in the plasma concentration of analgesic drug.  相似文献   
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