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   1132篇
  免费   58篇
  国内免费   6篇
耳鼻咽喉   74篇
儿科学   49篇
妇产科学   41篇
基础医学   88篇
口腔科学   29篇
临床医学   101篇
内科学   201篇
皮肤病学   4篇
神经病学   187篇
特种医学   50篇
外科学   144篇
综合类   3篇
预防医学   37篇
眼科学   41篇
药学   86篇
中国医学   5篇
肿瘤学   56篇
  2023年   3篇
  2022年   5篇
  2021年   27篇
  2020年   10篇
  2019年   20篇
  2018年   36篇
  2017年   16篇
  2016年   24篇
  2015年   22篇
  2014年   31篇
  2013年   46篇
  2012年   66篇
  2011年   73篇
  2010年   26篇
  2009年   27篇
  2008年   52篇
  2007年   60篇
  2006年   57篇
  2005年   47篇
  2004年   46篇
  2003年   54篇
  2002年   54篇
  2001年   32篇
  2000年   19篇
  1999年   32篇
  1998年   16篇
  1997年   12篇
  1996年   10篇
  1995年   6篇
  1994年   5篇
  1993年   4篇
  1992年   18篇
  1991年   18篇
  1990年   23篇
  1989年   34篇
  1988年   28篇
  1987年   24篇
  1986年   20篇
  1985年   23篇
  1984年   16篇
  1983年   12篇
  1982年   10篇
  1981年   4篇
  1980年   8篇
  1979年   2篇
  1978年   4篇
  1976年   2篇
  1972年   2篇
  1970年   2篇
  1969年   2篇
排序方式: 共有1196条查询结果,搜索用时 62 毫秒
71.
The objective of this study was to determine the efficacy of pindolol as an augmentor of fluoxetine in treatment-resistant panic disorder (PD). Twenty-five outpatients having PD with or without agoraphobia were included. These patients had not responded to two different trials with antidepressants and an 8-week trial of fluoxetine 20 mg/day. Treatment-resistant PD was defined as a less than 20% reduction in score on the Panic Self-Questionnaire (number of attacks per week) (PSQ) and the Clinical Anxiety Scale With Panic Attacks (CAS+PA). These patients continued to receive fluoxetine 20 mg/day and were randomly assigned to additionally receive either pindolol (2.5 mg three times daily) or placebo for the following 4 weeks. Evaluations were performed weekly using the Hamilton Rating Scale for Anxiety, the Hamilton Rating Scale for Depression (HAM-D), the CAS+PA, the NIMH Anxiety Scale, the PSQ, and the Clinical Global Impression Scale. The data were analyzed using a repeated-measures analysis of variance (ANOVA) and a t-test for independent samples. Patients treated with the combination of pindolol and fluoxetine (N = 13) demonstrated a significant improvement over the patients treated with fluoxetine and placebo on all rating scales, with the exception of HAM-D. The statistical differences were shown using the repeated-measures ANOVA (baseline, week 2, week 4) and also with t-tests from the second week of the trial. These preliminary results demonstrate that pindolol has an augmenting effect on fluoxetine in patients with treatment-resistant PD.  相似文献   
72.
Malignant neurilemmoma of parotid gland   总被引:1,自引:0,他引:1  
  相似文献   
73.
The serotonergic system has been implicated in both the aetiology and pharmacological treatment of obsessive compulsive disorder. In pharmacological challenge tests, mCPP, a 5-HT agonist, with an affinity for 5HT2C as well as 5HT1A and 5HT1D, receptors, was associated with a transient exacerbation of obsessive compulsive symptoms. Chronic administration of mCPP was found to bring about some relief of these symptoms. Sumatriptan is an antimigraine agent, which interacts most potently with 5HT1D receptors. In the cases to be presented, we report the effects of chronic administration of Sumatriptan to three severe, treatment resistant, OCD patients. Following chronic administration of sumatriptan, these patients, who have been resistant to any former pharmacological treatment, responded with an improvement in their depression and a modest reduction in their obsessive compulsive symptoms.  相似文献   
74.
75.
Given that thrombin is ubiquitously expressed at sites of vascular injury, and that osteogenic cells express receptors for thrombin, we questioned whether thrombin could attract osteogenic cells to a bony wound. Using a scratch wound assay, thrombin stimulated a significant increase in migration of osteogenic cultures of primary marrow cells. This effect was dependent on thrombin proteolytic activity; however, thrombin was unable to stimulate the migration of a more differentiated marrow-derived osteogenic cell line. To better understand the role of thrombin in osteoprogenitor migration, we developed an osteoprogenitor migration assay that combines a modified Boyden chamber with a bone nodule assay. Primary cells that migrated through the transwell filter in the presence of thrombin formed significantly more bone nodules compared to the condition without thrombin. This was not due to proliferation or differentiation effects of thrombin. In contrast, thrombin was unable to stimulate an increase in the number of nodules for the more differentiated osteogenic cell line. Thus, our results suggest that thrombin exhibits differential motogenic effects on osteogenic cells depending on their differentiation state. The cell migration/bone nodule assay described here is the first assay that can be specifically used to examine the effects of factors on the migration of osteoprogenitor cells, particularly those derived from primary populations.  相似文献   
76.
77.
78.
Zohar E  Ellis M  Ifrach N  Stern A  Sapir O  Fredman B 《Anesthesia and analgesia》2004,99(6):1679-83, table of contents
To assess the blood-sparing efficacy of tranexamic acid (TA) administered orally or via a variable IV infusion, 80 healthy patients undergoing elective total knee replacement were studied according to a prospective, controlled, randomized, single-blinded study design. Patients were allocated to one of four treatment groups. In group TA-long, 30 min before deflation of the limb tourniquet, an IV bolus dose of TA 15 mg/kg was administered over 30 min. Thereafter, a constant IV infusion of 10 mg . kg(-1) . h(-1) was administered until 12 h after final deflation of the limb tourniquet. In group TA-short, a similar regimen was followed; however, the constant IV infusion was discontinued 2 h after final deflation of the limb tourniquet (time of discharge from the postanesthesia care unit). Thereafter, oral TA 1 g was administered after 6 and 12 h. In group TA-oral, 60 min before surgery an oral dose of TA 1 g was administered. After surgery, a similar dose of TA was administered every 6 h for the next 18 h. In the control group, TA was not administered. At patient discharge, postoperative allogeneic blood administration was significantly more in group Control when compared with each of the three TA treatment groups. Because oral drug administration is simple and does not require specific infusion equipment, the authors suggest that oral TA is a superior blood-sparing strategy compared with IV drug administration.  相似文献   
79.
Breasts are usually only incidentally included in computed tomography (CT) scans of the abdomen and chest in spite of the fact that pathologic findings are not rare. Because postpartum women are normally healthy, they rarely require examination; therefore, the presentation of lactating breasts on a CT scan is poorly known. The most common postpartum breast feature is engorgement, which is characterized by painful swelling associated with a sudden increase in milk volume, lymphatic and vascular congestion, and interstitial edema. Its appearance on a CT scan does not seem to have been described in the literature to date. The CT picture of a lactating breast shows the enlarged gland with bilateral cord- and mass-like hyperattenuated tissue. After abrupt cessation of breast-feeding, the edema component supervenes and breast tissue may become hypoattenuated. In such cases, further ultrasound evaluation is needed. We present 3 cases of postpartum breast engorgement as seen on CT.  相似文献   
80.
BACKGROUND: Physical exercise during childhood has been shown to enhance bone mineral density, thus reducing the risk of osteoporosis. OBJECTIVE: To examine bone properties, as measured by quantitative ultrasound, in prepubertal and early-pubertal female athletes engaged in impact and nonimpact sports. DESIGN: Survey. SETTING: General community. PARTICIPANTS: Twenty-five acrobatic gymnasts, 21 swimmers, and 21 control subjects. Athletes had been training for at least 1(1/2) years. MAIN OUTCOME MEASURE: Bone speed of sound (bilateral) at the distal radius and the midtibia. RESULTS: Gymnasts were significantly shorter and lighter than swimmers and control girls (P<.001) but had a body mass index similar to that of swimmers. Adiposity was lower in athletes than in controls. Speed of sound did not correlate with measures of body size. Higher mean +/- SD radial speed of sound values (nondominant side) were observed in gymnasts (3764 +/- 104 m/s; P =.045) than in swimmers and control girls (3732 +/- 99 and 3721 +/- 83 m/s, respectively). Mean +/- SD tibial speed of sound values (nondominant side) were similar in gymnasts and swimmers (3629 +/- 87 and 3619 +/- 78 m/s, respectively) and higher in the athletic groups than in the control group (3516 +/- 127 m/s; P<.001). In all 3 groups, no differences were observed between dominant and nondominant sides in the radii or tibias. CONCLUSIONS: Physical exercise, impact and nonimpact, is related to enhanced bone properties, as measured by quantitative ultrasound. Longitudinal studies using various modes of bone evaluation are necessary to determine the long-term effect of various types of exercise on bone properties.  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