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   876篇
  免费   56篇
  国内免费   4篇
耳鼻咽喉   1篇
儿科学   28篇
妇产科学   5篇
基础医学   110篇
口腔科学   11篇
临床医学   112篇
内科学   86篇
皮肤病学   9篇
神经病学   21篇
特种医学   61篇
外科学   194篇
综合类   15篇
一般理论   1篇
预防医学   109篇
眼科学   5篇
药学   138篇
肿瘤学   30篇
  2022年   4篇
  2021年   16篇
  2020年   6篇
  2019年   14篇
  2018年   10篇
  2017年   7篇
  2016年   9篇
  2015年   7篇
  2014年   23篇
  2013年   31篇
  2012年   44篇
  2011年   25篇
  2010年   25篇
  2009年   16篇
  2008年   48篇
  2007年   25篇
  2006年   19篇
  2005年   44篇
  2004年   56篇
  2003年   45篇
  2002年   47篇
  2001年   36篇
  2000年   35篇
  1999年   43篇
  1998年   30篇
  1997年   20篇
  1996年   23篇
  1995年   16篇
  1994年   19篇
  1993年   18篇
  1992年   18篇
  1991年   14篇
  1990年   13篇
  1989年   17篇
  1988年   13篇
  1987年   23篇
  1986年   14篇
  1985年   11篇
  1984年   4篇
  1983年   4篇
  1981年   4篇
  1980年   3篇
  1979年   4篇
  1978年   5篇
  1977年   3篇
  1976年   3篇
  1975年   6篇
  1973年   2篇
  1972年   2篇
  1971年   4篇
排序方式: 共有936条查询结果,搜索用时 15 毫秒
1.
OBJECTIVE: Exercise advice is the main treatment for symptom relief in the UK for patients with mild to moderate Intermittent Claudication (IC). Would a weekly exercise and motivation class for 6 months offer adjuvant benefit over written and verbal exercise advice alone? PATIENTS AND METHODS: Fifty-nine patients attending a regional vascular centre for whom IC was the main factor affecting mobility were randomised to either exercise advice alone (n=30) or exercise advice with a once a week 45 min supervised exercise/motivation class (n=29). The mean age was 68 years. Baseline and 6-month assessment included a Quality of Life Questionnaire--the Short-Form-36, the Charing Cross Symptom Specific Claudication Questionnaire (CCCQ) and treadmill walking distance (3.5 km/h 12%). RESULTS: At 6-month follow-up the supervised exercise group had improved their treadmill walking by 129% compared to 69% in the advice alone group (p=0.001). This significant improvement was maintained at the subsequent 9 and 12-month follow-up assessments. By the 9-month stage the advice only group CCCQ score had improved 16% from baseline, while the supervised exercise group had a significantly better 43% improvement in base line score (p<0.05). Self reported frequency of walks was higher in the exercise class group being significant for improvement in CCCQ score. CONCLUSION: A weekly, supervised exercise and motivation class for a 6-month period provides a significant improvement in patients' symptoms, quality of life, and distance walked compared with advice alone and this improvement continues after attendance at class has ceased.  相似文献   
2.
3.
4.
Image-directed percutaneous biopsies with a biopsy gun   总被引:3,自引:0,他引:3  
Core tissue for histologic study is believed by many pathologists to be more diagnostic than material from needle aspiration. Recently, a biopsy "gun" has been introduced, which simplifies core biopsies. With this device, 182 biopsies of multiple anatomic sites were performed with ultrasonic, computed tomographic, and fluoroscopic guidance and 18-gauge needles. High-quality histopathologic specimens were obtained in 177 of the biopsies, and diagnostic target tissue was obtained in 167. Only three significant complications occurred: one bleeding complication that required transfusion and two cases of pneumothorax that necessitated placement of chest tubes. The biopsy gun eliminated the disjointed movements of conventional "skinny" needle biopsies, and none of the samples demonstrated significant "crush" artifact or obscuring blood, problems that are commonly associated with manual biopsy techniques. Patient discomfort was decreased with this system compared with that of manual biopsies, and the total procedure time was reduced. Because of these distinct advantages, the authors now use the biopsy gun exclusively for all percutaneous biopsies and recommend that other institutions consider the use of this biopsy method.  相似文献   
5.
6.
Psychological screening and the success of donor insemination   总被引:1,自引:0,他引:1  
In a previous case series, a psychologist‘s rating ofcouples’ emotional adjustment and readiness for donorinsemination was predictive of pregnancy rates. We attemptedto replicate this finding with an extended series of 120 consecutivecouples in which each spouse filled out questionnaires whenevaluated for donor insemination. The Stress and InfertilityQuestionnaire measured specific attitudes and anxieties aboutdonor insemination. The Brief Symptom Inventory assessed psychologicaldistress. The Dyadic Adjustment Scale measured marital happiness.A psychologist used these questionnaires to rate the couple‘soverall adjustment in regard to donor insemination. Those couplesrated as distressed had a session of psychological counselling.Outcome was reviewed at a mean of 20 months after evaluation,with categories of pregnancy, continuing donor insemination,failure to begin the programme, or dropped out. For the 120couples overall, psychological factors did not predict pregnancyoutcome. Younger age of the wife did predict higher pregnancyrates  相似文献   
7.
Negative regulation of cytokine signaling   总被引:5,自引:0,他引:5  
  相似文献   
8.
9.
10.
In this study we have looked at the effect of lipopolysaccharide (LPS) on the surface antigen expression of cultured monocytes. Monocytes were purified from peripheral blood mononuclear cells (PBMC) and cultured in the presence or absence of LPS. The cultured cells were then stained with anti-MO3, anti-IL-2R and anti-CD4 MoAbs. We have shown that freshly isolated monocytes are IL-2R- and MO3-negative and express CD4 in low density. After overnight culture, without LPS, the expression of these surface markers remained relatively unchanged. However, in the presence of LPS (1 microgram/ml) CD4 expression was reduced to undetectable levels while the expression of IL-2R and MO3 was induced to maximal density. This effect of LPS on monocyte surface antigen expression was demonstrated with LPS preparations from Escherichia coli, Salmonella typhi and Vibrio cholerae. Surface antigen expression after 7 days culture in medium supplemented with non-heat-inactivated serum was essentially as seen after overnight culture, with the exception that LPS-induced IL-2R expression was transient. The ability to prepare monocytes that maintained surface CD4 expression after overnight culture was donor dependent.  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