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   30544篇
  免费   5675篇
  国内免费   136篇
耳鼻咽喉   131篇
儿科学   767篇
妇产科学   1846篇
基础医学   2178篇
口腔科学   237篇
临床医学   16304篇
内科学   5000篇
皮肤病学   248篇
神经病学   1632篇
特种医学   499篇
外科学   2589篇
综合类   72篇
现状与发展   1篇
一般理论   10篇
预防医学   2370篇
眼科学   96篇
药学   808篇
中国医学   22篇
肿瘤学   1545篇
  2024年   75篇
  2023年   811篇
  2022年   185篇
  2021年   464篇
  2020年   748篇
  2019年   433篇
  2018年   1347篇
  2017年   1511篇
  2016年   1612篇
  2015年   1703篇
  2014年   1871篇
  2013年   2239篇
  2012年   1260篇
  2011年   1571篇
  2010年   1532篇
  2009年   1827篇
  2008年   1450篇
  2007年   1411篇
  2006年   1411篇
  2005年   1372篇
  2004年   1287篇
  2003年   1171篇
  2002年   1076篇
  2001年   558篇
  2000年   315篇
  1999年   535篇
  1998年   744篇
  1997年   812篇
  1996年   725篇
  1995年   657篇
  1994年   482篇
  1993年   410篇
  1992年   290篇
  1991年   278篇
  1990年   271篇
  1989年   213篇
  1988年   171篇
  1987年   169篇
  1986年   155篇
  1985年   150篇
  1984年   120篇
  1983年   116篇
  1982年   96篇
  1981年   112篇
  1980年   77篇
  1979年   85篇
  1978年   68篇
  1977年   73篇
  1976年   70篇
  1972年   83篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
Since the mid-1970s, the Margaret Sanger Center of Planned Parenthood of New York City has prepared nurses and nurse midwives from less developed countries to be family-planning nurse practitioners. These nurse practitioners then provide services to patients, train other staff, and manage integrated family-planning clinics. More than 120 nurses and nurse midwives have arrived in groups of 10 at the Sanger Center, with 72 attending since 1981. Each course lasts 10 weeks. The core curriculum provides trainees with skills in women's health care including contraception, in training and advocacy, and in management of clinics. Whether, in the current period of scarce resources, cross-cultural training programs of this type remain a worthwhile investment, and if so, which of their components are most important to this success, is assessed.  相似文献   
102.
103.
The most common cause of illness in infancy and childhood is acute infection of the respiratory tract. Several recent studies have reported that life-threatening respiratory disease in infancy, such as pneumonia and bronchiolitis, is directly related to the smoking habits of parents. The effects of smoking are more hazardous to youngsters because babies and young children breathe more rapidly than adults. Because of this higher breathing rate, they inhale more air—and more pollution—in comparison to their total body weight. The harmful effects of cigarette smoking on infants and children and recommendations for specific interventions to minimize or eliminate this health hazard are discussed.  相似文献   
104.
A novel injectable scaffolding matrix (E-Matrix) has been developed to accelerate wound healing in diabetic foot ulcers. This porcine collagen-derived matrix is designed to mimic tertiary embryonic connective tissue and to stimulate fetal wound repair mechanisms including angiogenesis. In vitro and animal studies have indicated a beneficial effect on tissue growth and an acceptable safety profile. In this report, we describe the initial use of this product in a pilot study of six humans with chronic nonhealing diabetic foot ulcers. A dramatic initial response to injection was seen, with an average wound size reduction of 72% 2 weeks after injection. Randomized trials are underway to define the potential benefit of this new treatment modality for diabetic foot ulcers.  相似文献   
105.
106.
PROBLEM: To compare depressive symptoms in children with attention deficit hyperactivity disorder (ADHD) to those in healthy children, and to explore the influence of individual and family factors on level of depression. METHODS: Individual interviews with 68 children, ages 7 to 12 years, in order to complete the Children's Depression Inventory. FINDINGS: Children with ADHD reported significantly more depressive symptoms than did children without ADHD; 14.7% of children with ADHD reached the threshold of a 19 point score, which suggests clinical depression. No significant effects of individual and family factors on level of depression were found. CONCLUSIONS: Children with ADHD are more inclined to experience depressive symptoms than are healthy children. To plan appropriate interventions, nurses evaluating and working with children with ADHD should always consider a possible coexistence of depressive symptoms.  相似文献   
107.
OBJECTIVE: Early graft failure (EGF) is a life-threatening event still accounting for a significant percentage of early deaths after heart transplantation. We tested whether selected metabolic markers, including high-energy phosphate concentrations measured ex vivo in pre-transplant heart grafts by (31)P magnetic resonance spectroscopy (MRS) are related with early post-transplant outcome. METHODS: During a 3-year period, 26 heart grafts harvested in the vicinity of the transplantation centre were studied. Evaluation of transplantability was done conventionally. (31)P MRS was performed ex vivo approximately 60min after aortic cross-clamp to quantify ATP, P(i) and PCr concentration ratios. A MRS-score was defined as a combination of intracellular pH (pHi) and the PCr/P(i) ratio. EGF was defined as the need to abnormally extend circulatory support or to use more than two inotropes before weaning the patient from CPB after transplantation. The grafts were attributed to three groups as follows: A1, transplanted with uneventful outcome (n=14); A2, transplanted with subsequent EGF (n=3) and B, not suitable for transplantation (n=9). RESULTS: Significant differences between groups existed for the following metabolic markers: PCr/ATP (P=0.013), PCr/P(i) (P=0.0004), pHi (P=0.0016) and MRS-score (P=0.0001). The sensitivity, specificity and positive likelihood ratio for EGF with a MRS-score相似文献   
108.
109.
The effects of scopolamine, an anticholinergic drug, of trimipramine, a tricyclic antidepressant with both anticholinergic and sedative properties, of diazepam and a placebo, on explicit memory and repetition priming were assessed using a free-recall task and a word-stem completion task. Forty-eight healthy volunteers took part in this double-blind study. Diazepam provoked a dissociation between free recall, which was profoundly impaired, and word completion, which was spared. No significant changes in memory performances were observed in the scopolamine group; however, a significant correlation between explicit and implicit memory performances was observed in this group. At the low dose used, the effects of trimipramine on memory were mild. The results suggest that the cholinergic system is involved in the priming effect.  相似文献   
110.
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