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   385篇
  免费   44篇
  国内免费   12篇
耳鼻咽喉   5篇
儿科学   21篇
妇产科学   2篇
基础医学   13篇
口腔科学   12篇
临床医学   53篇
内科学   59篇
皮肤病学   13篇
神经病学   25篇
特种医学   42篇
外科学   34篇
综合类   7篇
预防医学   100篇
眼科学   11篇
药学   17篇
肿瘤学   27篇
  2023年   2篇
  2022年   5篇
  2021年   6篇
  2020年   5篇
  2019年   2篇
  2018年   11篇
  2017年   18篇
  2016年   9篇
  2015年   8篇
  2014年   11篇
  2013年   24篇
  2012年   7篇
  2011年   10篇
  2010年   12篇
  2009年   14篇
  2008年   7篇
  2007年   20篇
  2006年   11篇
  2005年   11篇
  2004年   12篇
  2003年   5篇
  2002年   4篇
  2001年   10篇
  2000年   9篇
  1999年   9篇
  1998年   10篇
  1997年   13篇
  1996年   15篇
  1995年   15篇
  1994年   15篇
  1993年   7篇
  1992年   8篇
  1991年   5篇
  1990年   4篇
  1989年   11篇
  1988年   8篇
  1987年   13篇
  1986年   9篇
  1985年   5篇
  1984年   11篇
  1983年   12篇
  1982年   8篇
  1980年   2篇
  1979年   2篇
  1978年   3篇
  1976年   4篇
  1972年   2篇
  1969年   2篇
  1943年   2篇
  1927年   1篇
排序方式: 共有441条查询结果,搜索用时 234 毫秒
21.
22.
23.
24.
The effect of a central fusion lock on forced vergence fixation disparity curve parameters, that is, magnitudes of fixation disparity and associated phoria, curve type and the central slope of the curve, was studied in 84 subjects because of ambiguity in the previous studies. It was found that the magnitudes of exo fixation disparity and exo associated phoria decreased significantly when they were measured with the central fusion lock. The central lock had no noticeable effect on the type of the curve, although, the central slope of the curve was flatter in the presence of the central lock.  相似文献   
25.
Direct sagittal computed tomographic scanning (DSCT) of the shoulder was performed in 42 symptomatic patients, six healthy volunteers, and two cadaver shoulders. Axial CT scanning and double-contrast arthrography with plain radiographs were performed in 41 patients for comparison. DSCT enabled correct identification of 27 of 29 lesions in 24 patients. Seventeen patients had normal shoulders. Axial CT scanning and DSCT together enabled correct identification of all lesions and were markedly superior to plain-film arthrography. DSCT enabled diagnosis of all cases of complete rotator cuff tear plus three cases of incomplete tear and three of rotator cuff atrophy not identified by the other techniques. Axial CT scanning was better than DSCT for diagnosis of Bankart lesions.  相似文献   
26.
目的:骨唾液酸蛋白在骨矿化形成方面扮演重要角色,实验观察其是否能诱导体外培养的人骨髓间充质干细胞向成骨细胞分化。方法:实验于2005—10/2006—12在解放军广州军区广州总医院医学实验科完成。①材料来源:选取在本院体检的健康志愿者2人,对本实验均知情同意。采用Ni-NTA亲和纯化技术,从本室构建的毕赤酵母GS115/pPICZaA-hbsp发酵上清中纯化重组人骨唾液酸蛋白。②实验方法:对健康志愿者进行髂骨穿刺抽取骨髓液,采用贴壁法培养得到骨髓间充质干细胞。设立4组:骨唾液酸蛋白组添加0.1nmol/L骨唾液酸蛋白;成骨诱导液组添加10nmol/L地塞米松、10mmol/L磷酸甘油、50mg/L抗坏血酸;联合组添加上述两组的所有试剂;空白对照组不添加任何处理因素;各组均处理细胞12d。⑧实验评估:光镜及电镜观察培养的细胞形态;以细胞计数法测定生长曲线,应用流式细胞仪分析细胞周期,采用免疫荧光细胞化学法和流式细胞分析检测干细胞标志物STRO-1的表达;生化试剂盒测定碱性磷酸酶活性;von Kossa染色法检测钙沉积。结果:①单个骨髓间充质干细胞为长梭形,经骨唾液酸蛋白处理后细胞大而扁平,原来密集的克隆分散开。②与空白对照组比较,骨唾液酸蛋白组引起细胞生长曲线右移,细胞Go/G,期比例平均增加12.09%(P〈0.01),S期比例减少65.92%(P〈0.01),STRO-1阳性细胞百分率下降26.54%(P〈0.01)。⑧与空白对照组比较,骨唾液酸蛋白组细胞碱性磷酸酶活性增加50.0%,成骨诱导液组增加59.5%,联合组增加71.43%,并且随着处理时间的延长,活性增加越显著。④空白对照组细胞vonKossa染色呈阴性,其余各组均呈阳性。其中联合组的黑色矿化结节体积最大、数目最多;骨唾液酸蛋白组的结节体积较小、数目较少;成骨诱导液组居中。结论:骨唾液酸蛋白对人骨髓间充质干细胞有促进成骨分化和矿化作用,且与成骨诱导液联用效果更佳。  相似文献   
27.
A patient without evident immune deficiency who received a transfusion of blood from a second-degree family member developed fatal transfusion- associated graft-versus-host disease (TA-GVHD). The donor was homozygous for an HLA haplotype for which the recipient was heterozygous (one-way HLA match). All 39 reported cases of TA-GVHD in immunocompetent patients were reviewed to ascertain the predisposing factors and to define the indications for irradiating blood for this population. HLA typing was described in 15 cases; in 13, including seven related and six unrelated donors, a one-way HLA match was present. Thirty-one (79%) of the 39 cases were reported from Japan (and 196 other cases are cited in the Japanese literature), but a one-way HLA match among unrelated donors at HLA-A, -B, -DR loci is only approximately two to four times more likely in Japanese persons than in whites. Fresh blood (< 96 hours old) was used in 29 (94%) of the 31 cases reported from Japan and in 33 (87%) of 38 cases overall (in one case, the age of the blood used was not reported). Thus, factors that appear to predispose to TA-GVHD in immunocompetent patients are a one- way HLA match, fresh blood, and, possibly, Japanese ancestry. Irradiating cellular blood components from all blood relatives of transfusion recipients will not completely eliminate the risk of TA- GVHD.  相似文献   
28.
Little is known about the association between antidepressant treatment-emergent adverse events and symptom nonremission in major depressive disorder. The objective of the current analysis was to determine whether particular baseline symptoms or treatment-emergent symptoms (adverse events) during the first 2 weeks are associated with nonremission after 8 weeks of treatment with a selective serotonin reuptake inhibitor (SSRI).Outpatients clinically diagnosed with nonpsychotic major depressive disorder were recruited from 6 primary and 9 psychiatric care sites. Participants (n = 206) were treated with an SSRI antidepressant (citalopram [20-40 mg/d], escitalopram [10-20 mg/d], fluoxetine [20-40 mg/d], paroxetine [20-40 mg/d], paroxetine CR [25-37.5 mg/d], or sertraline [50-150 mg/d]) for 8 weeks. Remission was defined as having a score of 5 or less on the 16-item Quick Inventory of Depressive Symptomatology-Clinician-Rated at week 8, or using last observation carried forward. Adverse events were identified using the 55-item Systematic Assessment for Treatment Emergent Events-Systematic Inquiry completed by participants at baseline and week 2.Findings indicated that the emergence of adverse events of weakness/fatigue, strange feeling, and trouble catching breath/hyperventilation at week 2 were independently associated with lack of remission even after controlling for the potential confounders of baseline depressive severity, anxious symptoms, antidepressant medication, chronic depression, race, burden of general medical comorbidity, and time in study. Hearing/seeing things appeared to have a protective effect. In conclusion, during SSRI treatment, the adverse events of weakness/fatigue, feeling strange, and trouble catching breath/hyperventilation are associated with nonremission, possibly due to lower adherence, early attrition, difficulty increasing the dose, and reduced efficacy.  相似文献   
29.
30.
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