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   4024篇
  免费   338篇
  国内免费   8篇
耳鼻咽喉   42篇
儿科学   99篇
妇产科学   28篇
基础医学   486篇
口腔科学   222篇
临床医学   447篇
内科学   759篇
皮肤病学   136篇
神经病学   382篇
特种医学   148篇
外科学   609篇
综合类   60篇
预防医学   247篇
眼科学   12篇
药学   517篇
中国医学   32篇
肿瘤学   144篇
  2022年   29篇
  2021年   66篇
  2020年   65篇
  2019年   74篇
  2018年   123篇
  2017年   70篇
  2016年   87篇
  2015年   89篇
  2014年   145篇
  2013年   180篇
  2012年   212篇
  2011年   192篇
  2010年   130篇
  2009年   111篇
  2008年   155篇
  2007年   186篇
  2006年   206篇
  2005年   156篇
  2004年   149篇
  2003年   164篇
  2002年   141篇
  2001年   137篇
  2000年   134篇
  1999年   136篇
  1998年   61篇
  1997年   51篇
  1996年   44篇
  1995年   45篇
  1994年   40篇
  1993年   35篇
  1992年   93篇
  1991年   80篇
  1990年   60篇
  1989年   58篇
  1988年   81篇
  1987年   59篇
  1986年   62篇
  1985年   62篇
  1984年   31篇
  1983年   30篇
  1982年   26篇
  1981年   28篇
  1980年   21篇
  1979年   34篇
  1978年   25篇
  1977年   20篇
  1975年   29篇
  1974年   21篇
  1973年   29篇
  1971年   20篇
排序方式: 共有4370条查询结果,搜索用时 15 毫秒
1.
2.
3.
Burning mouth syndrome (BMS) is a chronic oro‐facial pain disorder of unknown cause. It is more common in peri‐ and post‐menopausal women, and sex hormone dysregulation is believed to be an important causative factor. Psychosocial events often trigger or exacerbate symptoms, and persons with BMS appear to be predisposed towards anxiety and depression. Atrophy of small nerve fibres in the tongue epithelium has been reported, and potential neuropathic mechanisms for BMS are now widely investigated. Historically, BMS was thought to comprise endocrinological, psychosocial and neuropathic components. Neuroprotective steroids and glial cell line–derived neurotrophic factor family ligands may have pivotal roles in the peripheral mechanisms associated with atrophy of small nerve fibres. Denervation of chorda tympani nerve fibres that innervate fungiform buds leads to alternative trigeminal innervation, which results in dysgeusia and burning pain when eating hot foods. With regard to the central mechanism of BMS, depletion of neuroprotective steroids alters the brain network–related mood and pain modulation. Peripheral mechanistic studies support the use of topical clonazepam and capsaicin for the management of BMS, and some evidence supports the use of cognitive behavioural therapy. Hormone replacement therapy may address the causes of BMS, although adverse effects prevent its use as a first‐line treatment. Selective serotonin reuptake inhibitors (SSRIs) and serotonin and noradrenaline reuptake inhibitors (SNRIs) may have important benefits, and well‐designed controlled studies are expected. Other treatment options to be investigated include brain stimulation and TSPO (translocator protein 18 kDa) ligands.  相似文献   
4.

Background  

A standardised suction technique has been used to sample plasma proteins in dermal interstitial fluid (IF) serially for 5 to 6 days from a suction-induced skin mini-erosion. Increased protein concentrations ascribed to inflammation have been shown from day 1 onward. In this study, we assessed the effect of two different extraction pressures on IF sample composition.  相似文献   
5.
Men who had high, medium and low blood pressure at age 18 (compulsory screening for military service in Stockholm) were examined ten years later at age 28. Interviewers, having had no information regarding past or present blood pressure, interviewed them about life events experienced during the year preceding the examination. Men with high blood pressure at rest reported fewer life events for the past year than other men. Furthermore, high plasma adrenaline levels at rest were associated with few reported life events.  相似文献   
6.
1. The present study aimed to determine the feasibility of conducting a 5 year cardiovascular outcome trial of the treatment of 6000 elderly hypertensive patients in Australian general practices. 2. General practitioners (GPs) were invited to participate by mail and personal follow-up. Patient records were reviewed to identify subjects for a blood pressure (BP) screening programme. Blood pressure was measured on three occasions and eligible subjects were included if the average BP was 160 mmHg systolic or 90 mmHg diastolic if systolic BP was 140 mmHg. 3. Seven hundred and forty-one GPs were approached and 89 were enrolled in the study (12% of mail invites and 75% of those receiving a personal contact). In 16 practices where screening was completed, 82 000 records were reviewed to identify 4% patients eligible for screening. Twenty-two per cent of eligible subjects attended screening. Of 1938 subjects screened, 180 (9%) had BP 5=160/90 mmHg. Forty-seven percent of subjects (n = 916) were receiving antihypertensive therapy and 184 (20%) were withdrawn from therapy. One hundred and sixteen (63%) of these subjects had BP return to study entry levels within 6 weeks. Fifty-seven newly diagnosed and 81 previously treated subjects were randomized (7% of the screened population). 4. Based on the high participation rate of GPs, the response rate of patients to attend a BP screening programme and the 7% randomization to screening ratio for entry into the study, the ANBP2 pilot study has demonstrated that it is feasible to recruit subjects from Australian general practices to a cardiovascular outcome trial.  相似文献   
7.
8.
Dopamine inhibits Na+,K(+)-ATPase activity in several renal tubule segments and thereby regulates urinary Na+ excretion. We now show that a phosphopeptide of 31 amino acids, corresponding to residues 8-38 of the protein phosphatase inhibitor DARPP-32 (dopamine- and cAMP-regulated phosphoprotein of Mr 32,000), mimics the inhibitory action of dopamine on Na+,K(+)-ATPase activity in renal tubule cells from the ascending limb of the loop of Henle. The dephosphorylated form of the peptide is ineffective. The results indicate that dopamine acts through a protein phosphorylation pathway to regulate the activity of an ion pump. In addition, the data suggest that inhibition of protein phosphatase 1 by phophorylated DARPP-32 is a component of the mechanism by which dopamine regulates urinary Na+ excretion.  相似文献   
9.
Hyper-reactivity to non-specific challenges has been considered a hallmark of asthma and is defined as an abnormal responsiveness of the bronchial airways to a variety of provocative agents. The mechanisms underlying hyper-reactivity in the upper and lower airways are not known. By using the nose to study the inflammatory response possible abnormalities can be investigated carefully and pathophysiology of specific airway hyper-reactivities can be better understood. Other factors than merely constriction of the bronchial smooth muscles can cause narrowing of the free lumen to airflow. Functionally different and very distinct mucosal end-organ reactivities may also be increased. If these reactivities can be well assessed, specific airway hyper-reactivity can be defined. In the present report, specific mucosal end-organ hyper-reactivites in the allergic nasal mucosa are presented. Certain widespread hypotheses, such as the role of the eosinophil and the “increased absorption permeability theory”, are disputed.  相似文献   
10.
Neuroendocrine effects in printing workers exposed to toluene.   总被引:3,自引:0,他引:3  
The effect of exposure to toluene on plasma concentrations of testosterone, prolactin, luteinising (LH) and follicle stimulating (FSH) hormones was investigated in 47 rotogravure printers (time weighted average air toluene below 80 ppm; blood toluene concentration post-shift 0.19-7.99 mumol/l) and compared with a reference group. Increasing exposure concentrations of toluene (concentrations less than 5 to greater than 45 ppm) were significantly associated with decreasing plasma concentrations of LH (tau = -0.21, p = 0.003) and testosterone (tau = -0.25, p = 0.02). No correlation was found between cumulative exposure (ppm x years) and plasma hormone concentrations. The associations with exposure were present even when nine printers with heavy alcohol consumption were excluded. The study indicates an effect of low toluene exposure on the hypothalamus-pituitary axis, with a secondary decrease in testosterone secretion.  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