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   5685篇
  免费   337篇
  国内免费   32篇
耳鼻咽喉   50篇
儿科学   125篇
妇产科学   138篇
基础医学   769篇
口腔科学   90篇
临床医学   446篇
内科学   1247篇
皮肤病学   120篇
神经病学   629篇
特种医学   182篇
外科学   495篇
综合类   13篇
一般理论   1篇
预防医学   427篇
眼科学   65篇
药学   486篇
中国医学   17篇
肿瘤学   754篇
  2024年   12篇
  2023年   45篇
  2022年   117篇
  2021年   180篇
  2020年   121篇
  2019年   145篇
  2018年   159篇
  2017年   134篇
  2016年   140篇
  2015年   172篇
  2014年   213篇
  2013年   267篇
  2012年   477篇
  2011年   395篇
  2010年   222篇
  2009年   195篇
  2008年   353篇
  2007年   365篇
  2006年   377篇
  2005年   373篇
  2004年   338篇
  2003年   307篇
  2002年   273篇
  2001年   51篇
  2000年   42篇
  1999年   45篇
  1998年   49篇
  1997年   37篇
  1996年   43篇
  1995年   44篇
  1994年   27篇
  1993年   30篇
  1992年   20篇
  1991年   21篇
  1990年   22篇
  1989年   16篇
  1988年   20篇
  1987年   15篇
  1986年   13篇
  1984年   13篇
  1983年   13篇
  1980年   11篇
  1979年   11篇
  1978年   11篇
  1977年   11篇
  1976年   10篇
  1975年   14篇
  1974年   13篇
  1973年   9篇
  1970年   8篇
排序方式: 共有6054条查询结果,搜索用时 15 毫秒
41.
Glycogen synthase kinase (GSK3) is a constitutively active serine-threonine kinase associated to neurological and psychiatric disorders. GSK3 inhibition is considered a mediator of the efficacy of the mood-stabiliser lithium. This study aimed at comparing the central nervous system effect of lithium with the selective GSK3 inhibitors AZ1080 and compound A in biochemical, cellular, and behavioural tests. Collapsin response mediator protein 2 is a neuron-specific GSK3 substrate. Lithium, AZ1080, and compound A inhibited its phosphorylation in rat primary neurons with different pIC50. After systemic treatments with lithium or GSK3 inhibitors to assess specific functional responses, phosphorylation was unchanged in adult rat brain, while it was strongly inhibited by GSK3 inhibitors in pups, differently from lithium. Lithium may exert neurotrophic effect by increasing brain-derived neurotrophic factor (BDNF) levels: in the present experimental conditions, lithium exerted opposite effects on plasma BDNF levels compared to GSK3 inhibitors, suggesting this effect might not be necessarily mediated by GSK3 inhibition alone. While plasma thyroid-stimulating hormone and luteinising hormone were not affected by lithium, they were decreased by selective inhibitors. GH and prolactin displayed similar responses towards reduction. Follicle-stimulating hormone levels were not altered by treatments, whereas melatonin was specifically increased by AZ1080. Lithium impaired mouse spontaneous locomotion and decreased amphetamine-induced hyper-locomotion. AZ1080 had no effects on locomotion, while compound A reduced spontaneous locomotor activity without effects on amphetamine-induced hyper-locomotion. The present results indicate that a broad correlation between the effects of lithium and selective GSK3 inhibitors could not be devised, suggesting alternative mechanisms, whereas overlapping results could be obtained in specific assays.  相似文献   
42.
43.
Background: In the last few years, there has been increasing demand for aesthetic procedures to improve the effects of skin aging.

Aim: To evaluate the anti-aging efficacy, tolerability and skin changes induced by the topical products containing hyaluronic acid, N-acetyl glucosamine and gamma-amino butyric acid through instrumental techniques, clinical and subjective evaluation.

Patients/Method: Twenty female enrolled applied a day and night cream after applying a serum, once week applied a mask, for 2 months. A clinical assessment of smoothness, expression wrinkles, fine wrinkles and measurements of the parameters using Reveal Imager, X-Rite, Corneometer, Dermalab, Moisture Meter EpiD were taken at day 0, 15, 30 and 60 of study period. A final assessment questionnaire was submitted.

Results: The products were accepted by all the volunteers. The hydration (Corneometer: T0 49.17 vs T60 61.11, average variation 24.28%) (Moisture Meter EpiD: T0 45.73 vs T60 61.10, average variation 33.60%), elasticity (Dermalab: T0 56.06 vs T60 62.78, average variation 11.98%) and lightening of the skin (X-Rite: T0 60.23 vs T60 63.36, average variation 5.26%) improved. All changes were statistically significant (p < 0.05).

Conclusion: The efficacy of the topical products is confirmed by subjective, clinical and instrumental assessment. This should be a routine approach in dermatologic practice.  相似文献   

44.
45.
46.
47.
Alström Syndrome (ALMS), a recessive, monogenic ciliopathy caused by mutations in ALMS1, is typically characterized by multisystem involvement including early cone‐rod retinal dystrophy and blindness, hearing loss, childhood obesity, type 2 diabetes mellitus, cardiomyopathy, fibrosis, and multiple organ failure. The precise function of ALMS1 remains elusive, but roles in endosomal and ciliary transport and cell cycle regulation have been shown. The aim of our study was to further define the spectrum of ALMS1 mutations in patients with clinical features of ALMS. Mutational analysis in a world‐wide cohort of 204 families identified 109 novel mutations, extending the number of known ALMS1 mutations to 239 and highlighting the allelic heterogeneity of this disorder. This study represents the most comprehensive mutation analysis in patients with ALMS, identifying the largest number of novel mutations in a single study worldwide. Here, we also provide an overview of all ALMS1 mutations identified to date.  相似文献   
48.
We show the long‐term efficacy and safety of modified biliopancreatic diversion for the treatment of LPL‐deficiency. How this option compares with gene therapy is difficult to evaluate due to limited experience. Surgery may be the first option in patients in whom medical therapy is ineffective and gene therapy not applicable.  相似文献   
49.
50.
BACKGROUND & AIMS: Celiac disease (CD) has been associated with several genetic disorders, but has not been associated with hereditary fructose intolerance (HFI). METHODS: We identified CD in 4 female patients affected by HFI from among 38 Italian HFI patients. RESULTS: Three of these patients were children in whom the CD-associated signs were hypertransaminasemia, failure to thrive, low weight, and short stature, whereas the adult patient had protracted diarrhea notwithstanding a fructose-free diet. The incidence of CD in our group of HFI patients was higher (>10%) than in the general population (1%-3%) (P<.02). CONCLUSIONS: The possibility of an association between these 2 gastrointestinal disorders is important, particularly in the management of HFI patients with persisting symptoms.  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