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   3389792篇
  免费   269049篇
  国内免费   6088篇
耳鼻咽喉   48822篇
儿科学   108291篇
妇产科学   93640篇
基础医学   477858篇
口腔科学   99749篇
临床医学   308048篇
内科学   656214篇
皮肤病学   70672篇
神经病学   282437篇
特种医学   134970篇
外国民族医学   1261篇
外科学   509305篇
综合类   83009篇
现状与发展   4篇
一般理论   1428篇
预防医学   273048篇
眼科学   80166篇
药学   253171篇
  7篇
中国医学   6263篇
肿瘤学   176566篇
  2018年   33881篇
  2016年   29250篇
  2015年   33342篇
  2014年   47327篇
  2013年   72322篇
  2012年   97195篇
  2011年   102846篇
  2010年   60693篇
  2009年   58000篇
  2008年   97907篇
  2007年   103680篇
  2006年   104767篇
  2005年   101918篇
  2004年   98857篇
  2003年   95182篇
  2002年   93895篇
  2001年   153952篇
  2000年   159387篇
  1999年   135366篇
  1998年   39362篇
  1997年   35670篇
  1996年   35124篇
  1995年   34059篇
  1994年   32035篇
  1993年   29958篇
  1992年   109917篇
  1991年   106316篇
  1990年   103182篇
  1989年   99663篇
  1988年   92642篇
  1987年   91390篇
  1986年   86811篇
  1985年   83253篇
  1984年   63140篇
  1983年   54197篇
  1982年   32742篇
  1981年   29265篇
  1980年   27559篇
  1979年   60001篇
  1978年   42215篇
  1977年   35617篇
  1976年   33401篇
  1975年   35368篇
  1974年   43600篇
  1973年   41649篇
  1972年   38803篇
  1971年   36113篇
  1970年   33731篇
  1969年   31499篇
  1968年   28734篇
排序方式: 共有10000条查询结果,搜索用时 9 毫秒
91.
92.
AIM: Cardiovascular risk factors can be present in children and young adults. We previously found abnormal microvascular function in children who had glucose intolerance and insulin resistance. The aim of the present study was to investigate whether they also have abnormalities in left ventricular mass (LVM) and arterial stiffness. METHODS: We measured heart dimensions and LVM using echocardiography, and arterial stiffness using pulse wave analysis in 23 children with good glucose handling (postfeeding glucose: 3.9 to 5 mmol/L) and 21 with poor glucose handling (7.7 to 11.4 mmol/L). RESULTS: The time to pulse reflection was slightly shorter in the poorer glucose handlers (mean+/-SD: 143+/-10 vs 153+/-20 ms, P=0.04), suggestive of increased arterial stiffness. Also in this group, there were significant relationships between intraventricular septal thickness, blood pressure and body mass index, but not in the normal glucose handlers. CONCLUSIONS: We have found that normal children who are in the lowest quintile of glucose tolerance in comparison with their peers are exhibiting the first signs of arterial stiffening. In addition, we have seen the beginnings of a relationship between blood pressure, body mass index and left ventricular enlargement in this group. While these changes may not yet be clinically significant, their emergence might be further evidence of early predisposition to cardiovascular disease.  相似文献   
93.
背景:浴光疗同步治疗银屑病的有效性与UVB和死海盐的多靶点作用有关,同步治疗能够起到协同功效。目的:本回顾性研究的目的:①评价浴光疗同步治疗各种临床类型银屑病的有效性;②观察治疗反应有无不同;③获得更多数据以预测对不同类型银屑病的治疗效果,以便针对患者的类型选择治疗效果良好的方法。方法:根据Regensburg计划,患者接受了一个包括35次治疗的基础同步浴光疗疗程,随后又接受了一个包括25次治疗的维持治疗疗程。治疗中每周进行PASI评分以评价患者的皮肤状态。对373例按计划完成基础疗程的患者和其中78例完成维持疗程的患者的治疗…  相似文献   
94.
AIM: To evaluate whether the introduction of a strict protocol approach based on the systemic evaluation of critically ill pregnant women with complications of abortion affected outcome. SETTING: Indigent South Africans managed in the regional and tertiary hospitals of the Pretoria Academic Complex. METHOD: Since 1997 a standard definition of severe acute maternal morbidity (SAMM) has been used in the Pretoria Academic Complex. All cases of SAMM and maternal deaths were entered on the Maternal Morbidity and Mortality Audit System programme. A comparison of outcome of severely ill women who had complications of abortion was made between 1997-1998 (original protocol) and 2002-2004 (strict protocol). OUTCOME MEASURES: The mortality index and prevalence of organ system failure or dysfunction. RESULTS: In 1997-1998 there were 43 women with SAMM who survived and a further 10 maternal deaths due to complications of abortion, compared with 107 women with SAMM and 7 maternal deaths during 2002-2004. The mortality index declined from 18.9% in 1997-1998 to 6.1% in 2002-2004 (p = 0.02, odds ratio 0.28, 95% confidence limits 0.10 - 0.79). Significantly more women had hypovolaemic shock in 2002-2004 compared with 1997-1998 (54.4% v. 35.8%, p = 0.04), but fewer women had immune system failure including septic shock (18.4% v. 47.2%, p = 0.0002) and metabolic dysfunction (0 v. 5.7%, p = 0.03) and there was a trend to less renal failure (10.5% v. 22.6%, p = 0.06) and cardiac failure (4.4% v. 13.2%, p = 0.08). CONCLUSION: The strict protocol approach based on systemic evaluation in managing critically ill pregnant women with complications of abortion, coupled with an intensive, regular feedback mechanism, has been associated with a reduction in the mortality index.  相似文献   
95.
96.
97.
98.
99.
BACKGROUND: This study examines trends in the presentation and surgical management of acute diabetic foot problems in a single institution. METHOD: Prospective audit of all diabetic patients who had a primary procedure for critical lower limb ischaemia (CLI) and/or foot sepsis between 1st January 1990 and 31st December 2002. Primary and secondary intervention, mortality and limb salvage rate within 6 weeks of the index procedure were recorded. RESULTS: There were 661 patients (417 men and 244 women of median age 69, range 31-99, years) with 799 affected limbs. CLI alone was present in 625 (78%) limbs, combined CLI and foot sepsis in 53 (7%) and foot sepsis alone in 121 (15%). The primary intervention was minor amputation in 323 (40%) limbs, revascularisation in 288 (36%), major amputation in 185 (23%) and sympathectomy in three limbs. Within 6 weeks, 125 (16%) limbs required secondary intervention, the peri-procedural mortality rate was 38 of 924 (4%), and the limb salvage rates for patients with CLI, combined CLI and sepsis and sepsis alone were 66, 66 and 80%, respectively. There was a significant decline in the proportion of patients presenting with CLI alone and a significant increase in the proportion presenting with combined CLI and sepsis and sepsis alone. In patients with CLI alone, there was a significant increase in the primary major amputation rate and a significant decline in the minor amputation rate with no significant change in the revascularisation rate. CONCLUSION: There has been a progressive decline in the proportion of patients presenting with CLI alone and a greater proportion of patients presenting with an element of foot sepsis. In patients with CLI alone, the primary major amputation rate has increased at the expense of a decline in minor amputation rate.  相似文献   
100.
Setting goals to maintain hope.   总被引:3,自引:0,他引:3  
  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