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   6727篇
  免费   413篇
  国内免费   33篇
耳鼻咽喉   71篇
儿科学   152篇
妇产科学   126篇
基础医学   1119篇
口腔科学   48篇
临床医学   605篇
内科学   1551篇
皮肤病学   113篇
神经病学   778篇
特种医学   360篇
外科学   935篇
综合类   29篇
一般理论   6篇
预防医学   300篇
眼科学   96篇
药学   433篇
中国医学   6篇
肿瘤学   445篇
  2023年   32篇
  2022年   77篇
  2021年   185篇
  2020年   95篇
  2019年   148篇
  2018年   196篇
  2017年   144篇
  2016年   146篇
  2015年   206篇
  2014年   236篇
  2013年   364篇
  2012年   505篇
  2011年   531篇
  2010年   297篇
  2009年   294篇
  2008年   428篇
  2007年   453篇
  2006年   441篇
  2005年   451篇
  2004年   410篇
  2003年   322篇
  2002年   336篇
  2001年   76篇
  2000年   48篇
  1999年   66篇
  1998年   53篇
  1997年   57篇
  1996年   48篇
  1995年   52篇
  1994年   24篇
  1993年   25篇
  1992年   34篇
  1991年   17篇
  1990年   17篇
  1989年   26篇
  1988年   13篇
  1987年   13篇
  1986年   12篇
  1985年   18篇
  1984年   12篇
  1983年   17篇
  1982年   26篇
  1981年   23篇
  1980年   12篇
  1979年   16篇
  1978年   18篇
  1977年   9篇
  1976年   9篇
  1974年   11篇
  1972年   14篇
排序方式: 共有7173条查询结果,搜索用时 15 毫秒
1.
Recent focus on the neonatal intestinal microbiome has advanced our knowledge of the complex interplay between the intestinal barrier, the developing immune system, and commensal and pathogenic organisms. Despite the parallel role of the infant skin in serving as both a barrier and an interface for priming the immune system, large gaps exist in our understanding of the infantile cutaneous microbiome. The skin microbiome changes and matures throughout infancy, becoming more diverse and developing the site specificity known to exist in adults. Delivery method initially determines the composition of the cutaneous microbiome, though this impact appears transient. Cutaneous microbes play a critical role in immune system development, particularly during the neonatal period, and microbes and immune cells have closely intertwined, reciprocal effects. The unique structure of newborn skin influences cutaneous microbial colonization and the development of dermatologic pathology. The development of the infantile skin barrier and cutaneous microbiome contributes to future skin pathology. Atopic dermatitis flares and seborrheic dermatitis have been linked to dysbiosis, while erythema toxicum neonatorum is an immune response to the establishment of normal bacterial skin flora. Physicians who care for infants should be aware of the impact of the infantile skin microbiome and its role in the development of pathology. A better understanding of the origin and evolution of the skin microbiome will lead to more effective prevention and treatment of pediatric skin disease.  相似文献   
2.
Prolidase deficiency is a rare autosomal recessive disorder characterized by cutaneous ulcers, facial dysmorphism, recurrent infections, and intellectual disability. We report a unique case of a 6‐year‐old boy with prolidase deficiency and Crohn's disease who presented with lower extremity ulcers. Cutaneous ulcers due to prolidase deficiency are historically resistant to treatment, and we report success with the novel use of topical tacrolimus.  相似文献   
3.
4.
BACKGROUND: Changes in the hypothalamic-pituitary-adrenal (HPA) axis, as evidenced by patterns of cortisol secretion, have been of interest in understanding depression and anxiety disorders across the life span. Previous studies of pediatric depression have pointed to the period around sleep onset as a key time point for observing alterations in cortisol secretion associated with affective disorders. Evidence also indicates that pubertal development may influence the expression of HPA dysregulation. We hypothesized that adolescents with depression and youth with anxiety disorders exhibit elevated peri-sleep-onset cortisol. METHODS: Plasma cortisol was sampled every 20 min around sleep onset from children and adolescents with major depressive disorder (n = 116), anxiety disorders (n = 32), or no history of psychiatric disorder (control; n = 76). Sleep onset was determined by polysomnography. Classification of participants as children or adolescents was based on Tanner staging of pubertal maturation. RESULTS: Children with anxiety disorders had higher peri-sleep-onset cortisol than children with depression or control children. Adolescents with depression had marginally higher peri-sleep-onset cortisol than control adolescents and significantly higher peri-sleep-onset cortisol than children with depression. CONCLUSIONS: Depression and anxiety are associated with altered cortisol secretion around sleep onset, and these changes appear to be influenced by pubertal maturation.  相似文献   
5.
Clinical outcomes data can be used to facilitate patient management decisions, assess clinician and organizational performance, and to provide evidence for the effectiveness of surgery and rehabilitation. The validity of the inferences made from outcomes data are dependent on the validity of the outcomes measures themselves and the circumstances under which the data were collected, analyzed, and interpreted. Clinical outcomes may include measures of impairment of body structure and function, activity limitation, and participation restriction. However, because the relationship between impairment and the resulting activity limitation and participation restriction is not direct, and because activity limitations and participation restrictions are of the utmost concern to the athlete, the primary clinical outcome should be measures of activity limitation and participation restriction. Activity limitation and participation restriction may be measured either through direct observation of performance or by general or specific measures of health related quality of life. Clinical outcomes data must be collected systematically to ensure valid inferences from the data.  相似文献   
6.
7.
8.
We report on 7 patients (6 M, 1 F) with Coffin-Lowry syndrome who have a sensorineural hearing deficit in addition to developmental delay and characteristic facial changes. One of the patients also had a history of premature exfoliation of primary teeth. These are previously unappreciated clinical signs that may aid in the early diagnosis of Coffin-Lowry syndrome. Early diagnosis and recognition of a hearing deficit in the patient can lead to the use of hearing aids to help the patient achieve his or her full potential. These “;new”; clinical manifestations expand the phenotype of Coffin-Lowry syndrome and constitute an additional indication of pleiotropy. © 1993 Wiley-Liss, Inc.  相似文献   
9.
Activity at 5-HT1 and 5-HT2 receptor sites influences sexual behavior in male and female rats. 5-HT3 antagonists reportedly have no effect on copulatory activity in rats of either sex although they influence a variety of other behaviors. The effects of 5-HT3 agonists on sexual behavior are unknown. The following experiments were undertaken to assess the influence of the 5-HT3 agonists 1-phenylbiguanide (PBG) and 2-methyl-serotonin (2-Me-5-HT) on sexual behavior, when administered intracerebroventricularly. Consistent with earlier reports indicating that 5-HT1 and 5-HT2 receptor activity influences reproductive activity in a sex-dependent manner, PBG was found to facilitate male, but not female, rat sexual behavior. 2-Me-5-HT, however, failed to modify either female or male rat sexual activity. Evidence that PBG, but not 2-Me-5-HT, induces carrier-mediated dopamine release suggests that the effect of PBG in male rats is due to dopaminergic mediation. Overall, the present data indicate that 5-HT3 receptor activation has only slight effects on rat sexual behavior.  相似文献   
10.
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