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   908篇
  免费   97篇
  国内免费   10篇
耳鼻咽喉   4篇
儿科学   43篇
妇产科学   9篇
基础医学   99篇
口腔科学   18篇
临床医学   153篇
内科学   191篇
皮肤病学   19篇
神经病学   37篇
特种医学   167篇
外科学   78篇
综合类   31篇
预防医学   51篇
眼科学   16篇
药学   71篇
中国医学   6篇
肿瘤学   22篇
  2023年   7篇
  2022年   2篇
  2021年   8篇
  2020年   10篇
  2019年   18篇
  2018年   14篇
  2017年   13篇
  2016年   32篇
  2015年   68篇
  2014年   32篇
  2013年   32篇
  2012年   29篇
  2011年   32篇
  2010年   40篇
  2009年   42篇
  2008年   30篇
  2007年   17篇
  2006年   23篇
  2005年   23篇
  2004年   16篇
  2003年   18篇
  2002年   18篇
  2001年   18篇
  2000年   16篇
  1999年   27篇
  1998年   35篇
  1997年   46篇
  1996年   36篇
  1995年   31篇
  1994年   31篇
  1993年   23篇
  1992年   9篇
  1991年   14篇
  1990年   17篇
  1989年   26篇
  1988年   22篇
  1987年   16篇
  1986年   15篇
  1985年   14篇
  1984年   13篇
  1983年   13篇
  1982年   14篇
  1981年   12篇
  1980年   11篇
  1979年   3篇
  1978年   6篇
  1977年   4篇
  1976年   10篇
  1952年   1篇
  1948年   1篇
排序方式: 共有1015条查询结果,搜索用时 719 毫秒
921.
The study of psychosocial risk factors of pain among employees has typically focused on Karasek's job‐demand‐control model. The aim of the study was to examine the own and independent associations of job strain, organizational justice, workplace bullying, and work–home interface with pain. Data were collected through a postal survey to all 40, 45, 50, 55, and 60‐year‐old employees of the City of Helsinki in 2001 and 2002 (response rate 66%, N=5819, 80% women). Pain was measured with a three category outcome: no pain, acute pain or chronic pain. Adjustment was made for age, education, physical working conditions, BMI, smoking, and alcohol consumption. Among women, all psychosocial variables were associated with both acute and chronic pain when adjusted for confounders only. When psychosocial factors were additionally adjusted for each other, high job strain and both dimensions of work–home interface remained associated with both types of pain and repeatedly occurring bullying at workplace showed association with acute pain. Among men, when adjusted for confounders only, all psychosocial variables were associated with acute and chronic pain, except for family‐to‐work conflicts among those with acute pain. When adjusted mutually for all psychosocial variables, only bullying was associated with acute pain. Job strain and organizational justice showed associations with chronic pain. Future studies would benefit from a broad psychosocial framework. Investments to healthier psychosocial working environments are needed to tackle pain related problems among employees.  相似文献   
922.
The present experiments compared the peripheral and central pharmacological effects of three α2-adrenoceptor agonists: fadolmidine, clonidine, and dexmedetomidine after single intrathecal bolus injections at analgesic dose level in rats. Effects on mydriasis and cardiovascular functions were studied in anaesthetised rats, the effects on sedation/motor performance, body temperature, and gastrointestinal motility were evaluated in conscious rats, and also the effects on brain biogenic amines were studied. All compounds caused dose-dependent mydriasis, a decrease in blood pressure and heart rate, sedation, hypothermia, and inhibition of gastrointestinal transit, but in contrast to the analgesic effects, dexmedetomidine and clonidine were much more potent than fadolmidine. In accordance with the other systemic effects, dexmedetomidine and clonidine, but not fadolmidine, reduced the turnover of the monoamine neurotransmitters, noradrenaline and serotonin, in brain at the analgesic dose. The difference in the systemic effect profile between fadolmidine and clonidine or dexmedetomidine is most probably explained by differences in their ability to spread from the site of administration at the lumbar level into the periphery and/or the brain and further the concentrations of the compounds in the side of action. These results supports that intrathecally administered fadolmidine could have potential to be used as an analgesic agent with less subraspinal or spinal adverse effects at analgesic doses than dexmedetomidine and clonidine.  相似文献   
923.
外伤性腕部正中神经损伤治疗进展   总被引:1,自引:0,他引:1  
正中神经损伤在腕部切割伤中非常常见,其治疗方法多种多样。如需消除张力,应采用端端吻合修复;自体神经移植仍然是临床治疗长距离损伤的重要手段;当不能采用自体神经移植时,可以应用同种异体神经移植或自体组织移植;可降解生物、人工合成的神经导管在实验中表现出广阔的应用前景。本文就外伤性腕部正中神经损伤的治疗策略及有关进展作一综述。  相似文献   
924.

Background  

Streptococcus pneumoniae (pneumococcus) causes a wide range of clinical manifestations that together constitute a major burden of disease worldwide. The main route of pneumococcal transmission is through asymptomatic colonisation of the nasopharynx. Studies of transmission are currently of general interest because of the impact of the new conjugate-polysaccharide vaccines on nasopharyngeal colonisation (carriage). Here we report the first longitudinal study of pneumococcal carriage that records serotype specific exposure to pneumococci simultaneously within the two most important mixing groups, families and day care facilities.  相似文献   
925.
BACKGROUND: Low educational level is associated with an increased risk of coronary heart disease. The aim of the present study was to examine the relationships between education and common cardiovascular risk factors in young adults. METHODS: Trends in conventional risk factors of young adults aged 21, 24, 27 and 30 years in 1992 (n = 443) were examined across the educational groups as part of a 12-year follow-up study, the Cardiovascular Risk in Young Finns Study. Education was determined as participants' own educational level and as parental years of schooling. RESULTS: In males, subject's own education was related inversely and independently of parental school years to serum total and low density lipoprotein (LDL) cholesterol concentration, smoking and body mass index. In females, participant's own educational level associated inversely with smoking and physical inactivity. Parental school years was associated inversely and independently of one's own educational level with serum total and LDL cholesterol values and waist-hip ratio in females. In both genders, parental education was a stronger determinant of diet (butter use) than one's own educational level. CONCLUSIONS: The least educated young adults have adopted a more adverse lifestyle than the more educated. The risk factor profile in young adulthood, especially in females, is still affected by parental education. The influences of one's own and parental educational level on vascular risk profile should be taken into consideration when planning public health campaigns among young adults.  相似文献   
926.
927.
This study aimed to define the differences in lung function between British Caucasian and rural eastern Indian children, and to test the hypothesis that nutrition could account for such "ethnic" variation. To exclude confounders, a rural Indian setting was identified and children were screened for respiratory illness before lung function and nutritional characteristics were measured. Regression equations for this population have already been published. In this study, the lung function differences between rural eastern Indian ( n = 391) and mean predicted lung function for Caucasian children were characterized, matched for height and sex. In addition, stepwise multiple regression models were fitted to investigate the relative associations of lung function differences with body mass index (BMI), occipitofrontal circumference and age. Although the largest differences in the forced expiratory volume in 1 s (FEV 1 ) [girls 28.7 (27.3-30.1), boys 23.4 (22.2-24.6)] and forced vital capacity [girls 27.9 (26.4-29.4), boys 30.7 (29.6-31.9)] [values as mean difference in % predicted (95% confidence intervals)] ever reported between two populations were observed, differences in peak expiratory flow rate (PEFR) were small. BMI was strongly associated with inter-racial differences for FEV 1 for both sexes (boys β= -0.227, girls β= -0.353, p ≤0.001) and PEFR for girls ( β= -0.200, p ≤0.05) ( β= standardized coefficient).

Conclusion: Preventable nutritional factors may play a causal role in determining the FEV 1 differences between rural Indian and Caucasian children. As peak FEV 1 in youth influences respiratory morbidity in later life, it is important to define specific nutrient 1 deficiencies that may relate to poor FEV growth in these children.  相似文献   
928.
Persistent Müllerian Duct Syndrome (PMDS) is a rare disorder of the anti-mullerian hormone (AMH) synthesis or receptor, which due to the visual contrast of normal masculine external genitalia and female internal genitalia can raise confusion, sometimes during surgery for cryptorchidism or hernia inguinalis. For an acute and accurate analysis of such a situation a thorough knowledge of gonadal embryology is mandatory. The diagnosis is made on finding Müllerian structures in an individual with complete virilization without signs of hypocortisolism or exposition to maternal androgens during foetal life. Karyotyping and gonadal biopsy provide additional information to confirm the diagnosis. As the risk of malignant transformation is not clear, orchidopexy is advised in patients with cryptorchidism, with lifelong palpatory follow-up. In case of urologic symptoms, surgical removal of the Müllerian remnants can be considered, with careful attention for the vulnerable ductus deferens. Despite optimal treatment the prognosis regarding fertility remain uncertain.  相似文献   
929.
930.
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