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   6260篇
  免费   388篇
  国内免费   11篇
耳鼻咽喉   57篇
儿科学   339篇
妇产科学   143篇
基础医学   695篇
口腔科学   123篇
临床医学   462篇
内科学   1333篇
皮肤病学   94篇
神经病学   341篇
特种医学   238篇
外科学   1262篇
综合类   129篇
一般理论   3篇
预防医学   268篇
眼科学   152篇
药学   539篇
  1篇
中国医学   7篇
肿瘤学   473篇
  2023年   53篇
  2022年   86篇
  2021年   190篇
  2020年   103篇
  2019年   188篇
  2018年   215篇
  2017年   134篇
  2016年   153篇
  2015年   154篇
  2014年   242篇
  2013年   253篇
  2012年   407篇
  2011年   426篇
  2010年   215篇
  2009年   193篇
  2008年   331篇
  2007年   264篇
  2006年   274篇
  2005年   259篇
  2004年   252篇
  2003年   207篇
  2002年   202篇
  2001年   141篇
  2000年   150篇
  1999年   153篇
  1998年   34篇
  1997年   45篇
  1996年   41篇
  1995年   31篇
  1994年   27篇
  1993年   30篇
  1992年   104篇
  1991年   109篇
  1990年   76篇
  1989年   91篇
  1988年   76篇
  1987年   72篇
  1986年   70篇
  1985年   91篇
  1984年   47篇
  1983年   42篇
  1979年   27篇
  1977年   25篇
  1975年   25篇
  1974年   34篇
  1973年   39篇
  1972年   27篇
  1969年   24篇
  1968年   27篇
  1967年   22篇
排序方式: 共有6659条查询结果,搜索用时 31 毫秒
991.
K. T. Wong, K. Y. Ng, K. C. Ong, W. F. Ng, S. K. Shankar, A. Mahadevan, B. Radotra, I. J. Su, G. Lau, A. E. Ling, K. P. Chan, P. Macorelles, S. Vallet, M. J. Cardosa, A. Desai, V. Ravi, N. Nagata, H. Shimizu and T. Takasaki (2012) Neuropathology and Applied Neurobiology 38, 443–453 Enterovirus 71 encephalomyelitis and Japanese encephalitis can be distinguished by topographic distribution of inflammation and specific intraneuronal detection of viral antigen and RNA Aims: To investigate if two important epidemic viral encephalitis in children, Enterovirus 71 (EV71) encephalomyelitis and Japanese encephalitis (JE) whose clinical and pathological features may be nonspecific and overlapping, could be distinguished. Methods: Tissue sections from the central nervous system of infected cases were examined by light microscopy, immunohistochemistry and in situ hybridization. Results: All 13 cases of EV71 encephalomyelitis collected from Asia and France invariably showed stereotyped distribution of inflammation in the spinal cord, brainstem, hypothalamus, cerebellar dentate nucleus and, to a lesser extent, cerebral cortex and meninges. Anterior pons, corpus striatum, thalamus, temporal lobe, hippocampus and cerebellar cortex were always uninflamed. In contrast, the eight JE cases studied showed inflammation involving most neuronal areas of the central nervous system, including the areas that were uninflamed in EV71 encephalomyelitis. Lesions in both infections were nonspecific, consisting of perivascular and parenchymal infiltration by inflammatory cells, oedematous/necrolytic areas, microglial nodules and neuronophagia. Viral inclusions were absent. Conclusions: Immunohistochemistry and in situ hybridization assays were useful to identify the causative virus, localizing viral antigens and RNA, respectively, almost exclusively to neurones. The stereotyped distribution of inflammatory lesions in EV71 encephalomyelitis appears to be very useful to help distinguish it from JE.  相似文献   
992.
Behavioral disturbances are frequently the most challenging manifestations of dementia and are exhibited in almost all people with dementia. Common behavioral disturbances can be grouped into four categories: mood disorders (e.g., depression, apathy, euphoria); sleep disorders (insomnia, hypersomnia, night-day reversal); psychotic symptoms (delusions and hallucinations); and agitation (e.g., pacing, wandering, sexual disinhibition, aggression). They are often persistent, greatly diminish quality of life of patients and their family caregivers, cause premature institutionalization, and pose a high economic burden on the patient, family, and society. Behavioral disturbances can be prevented and treated with a multifaceted approach that supports dignity and promotes comfort and quality of life of persons with dementia and their family members. Management involves prompt treatment of reversible factors and management of symptoms using primarily individualized nonpharmacological interventions. Pharmacological interventions need to be restricted to behavioral emergencies and for short-term treatment of behavioral disturbances that pose imminent danger to self or others.  相似文献   
993.
Type 2 diabetes mellitus is a risk factor for incident heart failure and increases the risk of morbidity and mortality in patients with established disease. Secular trends in the prevalence of diabetes mellitus and heart failure forecast a growing burden of disease and underscore the need for effective therapeutic strategies. Recent clinical trials have demonstrated the shared pathophysiology between diabetes mellitus and heart failure, the synergistic effect of managing both conditions, and the potential for diabetes mellitus therapies to modulate the risk of heart failure outcomes. This scientific statement on diabetes mellitus and heart failure summarizes the epidemiology, pathophysiology, and impact of diabetes mellitus and its control on outcomes in heart failure; reviews the approach to pharmacological therapy and lifestyle modification in patients with diabetes mellitus and heart failure; highlights the value of multidisciplinary interventions to improve clinical outcomes in this population; and outlines priorities for future research.  相似文献   
994.
995.
996.
997.
998.

Background

Gallstone disease increases with age. The aims of this study were to measure short-term outcomes from cholecystectomy in hospitalized elderly patients, assess the effect of age, and identify predictors of outcomes.

Methods

This was a cross-sectional analysis, using the Health Care Utilization Project Nationwide Inpatient Sample (1999–2006), of elderly patients (aged 65–79 and ≥80 years) and a comparison group (aged 50–64 years) hospitalized for cholecystectomy. Linear and logistic regression models were used to evaluate age and outcome relationships. Main outcomes were in-hospital mortality, complications, discharge disposition, mean length of stay, and cost.

Results

A total of 149,855 patients aged 65 to 79 years, 62,561 patients aged ≥ 80 years, and 145,675 subjects aged 50 to 64 years were included. Elderly patients had multiple biliary diagnoses and longer times to surgery from admission and underwent more open procedures. Patients aged 65 to 79 years and those aged ≥80 years had higher adjusted odds of mortality (odds ratios [ORs], 2.36 and 5.91, respectively), complications (ORs, 1.57 and 2.39), nonroutine discharge (ORs, 3.02 and 10.76), longer length of stay (ORs, 1.11 and 1.31), and higher cost (ORs, 1.09 and 1.22) than younger patients.

Conclusions

Elderly patients undergoing inpatient cholecystectomy have complex disease, with worse outcomes. Longer time from admission to surgery predicts poor outcome.  相似文献   
999.
Nayak  C.  Sinha  S.  Nagappa  M.  Nagaraj  K.  Kulkarni  G. B.  Thennarasu  K.  Taly  A. B. 《Sleep & breathing》2016,20(1):263-269
Sleep and Breathing - Although the relationship between sleep and migraine has been widely reported, studies on sleep microstructure are few. The aim was to study and compare microstructural...  相似文献   
1000.
Inflammatory bowel disease (IBD) is an established risk factor for colorectal cancer. Recent reports suggesting IBD is also a risk factor for prostate cancer (PC) require further investigation. We studied 218 084 men in the population-based UK Biobank cohort, aged 40 to 69 at study entry between 2006 and 2010, with follow-up through mid-2015. We assessed the association between IBD and subsequent PC using multivariable Cox regression analyses, adjusting for age at assessment, ethnic group, UK region, smoking status, alcohol drinking frequency, body mass index, Townsend Deprivation Index, family history of PC and previous prostate-specific antigen testing. Mean age at study entry was 56 years, 94% of the men were white, and 1.1% (n = 2311) had a diagnosis of IBD. After a median follow-up of 78 months, men with IBD had an increased risk of PC (adjusted hazard ratio [aHR] = 1.31, 95% confidence interval [CI] = 1.03-1.67, P = .029). The association with PC was only among men with the ulcerative colitis (UC; aHR = 1.47, 95% CI = 1.11-1.95, P = .0070), and not Crohn's disease (aHR 1.06, 95% CI = 0.63-1.80, P = .82). Results are limited by lack of data on frequency of health care interactions. In a large-scale, prospective cohort study, we detected an association between IBD, and UC specifically, with incident PC diagnosis.  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