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   118784篇
  免费   7761篇
  国内免费   6952篇
  2023年   1379篇
  2022年   1398篇
  2021年   3107篇
  2020年   2839篇
  2019年   3567篇
  2018年   2874篇
  2017年   2726篇
  2016年   3343篇
  2015年   5128篇
  2014年   8618篇
  2013年   8973篇
  2012年   6709篇
  2011年   7551篇
  2010年   5665篇
  2009年   6178篇
  2008年   6463篇
  2007年   6797篇
  2006年   5112篇
  2005年   4561篇
  2004年   3426篇
  2003年   3048篇
  2002年   2786篇
  2001年   2334篇
  2000年   2101篇
  1999年   1995篇
  1998年   1736篇
  1997年   1440篇
  1996年   1410篇
  1995年   1507篇
  1994年   1404篇
  1993年   1420篇
  1992年   1275篇
  1991年   1289篇
  1990年   1074篇
  1989年   1008篇
  1988年   917篇
  1987年   764篇
  1986年   669篇
  1985年   941篇
  1984年   1259篇
  1983年   762篇
  1982年   1046篇
  1981年   972篇
  1980年   735篇
  1979年   683篇
  1978年   452篇
  1977年   427篇
  1976年   385篇
  1974年   270篇
  1973年   270篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Diabetic foot is a serious complication that causes lower extremity amputations. The aim of this study was to identify the patient’s awareness about risk factors for diabetic foot disease and to explore the knowledge and foot care practices among diabetic patients in a Saudi population. This cross-sectional study was conducted in King Khalid University Hospital (KKUH), King Abdulaziz University Hospital (KAUH), King Fahad Medical City, National Guard Hospital, Military Hospital, and Prince Salman Hospital capital city of Saudi Arabia. Patients were eligible if they had diabetes foot disease, signed the consent form, and completed the questionnaire. We selected 350 patients from different hospitals between November-2011 and April-2012. The majority of patients (68%) were selected from King Saud University hospitals. The mean age of patients was 50.87 ± 15.9 years with a range of 20–90 years. The majority of patients were male (64.3%) and had a family history of hypertension (55.4%), high total cholesterol (58.6%), and other diabetes (58.9%). A family history of smoking, a major risk factor for diabetic foot, was found in 20.3% of cases. Sixty percent of the patients were using oral medications, 27.1% were using insulin therapy, 10% were using both oral and insulin therapies, and 10% were on diet. In our study, 19.4% of participants were illiterate while 80.6% had a high school or university level education. Our findings also revealed that some patients had a lack of knowledge concerning diabetic foot disease and future complications. Patients are unaware of the risk factors for diabetes foot and practice poor foot care. Awareness programs should be mandatory in all hospitals and diabetes clinics to help compensate for the lack of awareness and lack of podiatric educational services. Such programs may decrease the risk of diabetes foot disease.  相似文献   
2.
3.
4.
5.
6.
7.
8.
9.
Degeneration of mesencephalic dopaminergic (mesDA) neurons is the pathological hallmark of Parkinson’s diseae. Study of the biological processes involved in physiological functions and vulnerability and death of these neurons is imparative to understanding the underlying causes and unraveling the cure for this common neurodegenerative disorder. Primary cultures of mesDA neurons provide a tool for investigation of the molecular, biochemical and electrophysiological properties, in order to understand the development, long-term survival and degeneration of these neurons during the course of disease. Here we present a detailed method for the isolation, culturing and maintenance of midbrain dopaminergic neurons from E12.5 mouse (or E14.5 rat) embryos. Optimized cell culture conditions in this protocol result in presence of axonal and dendritic projections, synaptic connections and other neuronal morphological properties, which make the cultures suitable for study of the physiological, cell biological and molecular characteristics of this neuronal population.  相似文献   
10.
Abstract. Anopheles stephensi mosquitoes which had fed upon mice infected with Plasmodium yoelii nigeriensis malaria parasites produced significantly fewer eggs than mosquitoes fed on an uninfected mouse. Fecundity reduction was more pronounced when the bloodmeal contained malaria gametocytes and the mosquitoes developed oocysts. Egg production and haematin excretion were correlated for uninfected bloodfed mosquitoes; the presence of P.y. nigeriensis in the blood affected this relationship. Reduced fecundity was associated with a significant reduction of bloodmeal size (measured by haematin excretion) in mosquitoes which ingested gametocytaemic blood. The bloodmeal size in mosquitoes fed on parasitaemic blood without gametocytes was not significantly reduced. The use of haematin assays for determination of bloodmeal size in mosquitoes is discussed.  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