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   63137篇
  免费   4670篇
  国内免费   332篇
耳鼻咽喉   634篇
儿科学   1605篇
妇产科学   1539篇
基础医学   7835篇
口腔科学   1537篇
临床医学   6352篇
内科学   14340篇
皮肤病学   809篇
神经病学   4998篇
特种医学   1912篇
外国民族医学   2篇
外科学   9735篇
综合类   1009篇
现状与发展   1篇
一般理论   103篇
预防医学   5235篇
眼科学   1850篇
药学   4426篇
中国医学   139篇
肿瘤学   4078篇
  2023年   268篇
  2022年   375篇
  2021年   1155篇
  2020年   724篇
  2019年   1009篇
  2018年   1243篇
  2017年   847篇
  2016年   968篇
  2015年   1136篇
  2014年   1775篇
  2013年   2811篇
  2012年   3774篇
  2011年   4116篇
  2010年   2347篇
  2009年   2191篇
  2008年   4009篇
  2007年   4193篇
  2006年   4021篇
  2005年   4115篇
  2004年   3844篇
  2003年   3454篇
  2002年   3416篇
  2001年   736篇
  2000年   631篇
  1999年   724篇
  1998年   741篇
  1997年   609篇
  1996年   492篇
  1995年   491篇
  1994年   466篇
  1993年   440篇
  1992年   534篇
  1991年   509篇
  1990年   417篇
  1989年   438篇
  1988年   396篇
  1987年   373篇
  1986年   356篇
  1985年   420篇
  1984年   432篇
  1983年   394篇
  1982年   528篇
  1981年   443篇
  1980年   485篇
  1979年   301篇
  1978年   321篇
  1977年   321篇
  1976年   261篇
  1975年   287篇
  1974年   246篇
排序方式: 共有10000条查询结果,搜索用时 78 毫秒
41.
This is a case study of a patient with recurrent synovial chondromatosis. It shows some relevant images. It also provides possibilities for why this patient may have had a recurrence and how this was managed.  相似文献   
42.
Cardiovascular risk increases with each decrement in renal function. Low-density lipoprotein (LDL) cholesterol levels are not associated with increased mortality, but high-density lipoprotein (HDL) levels are inversely associated with cardiovascular risk. Lipoprotein composition with increased abundance of small dense LDL and HDL and reduced levels of more buoyant isoforms is similar to what is found in states of insulin resistance and in the metabolic syndrome (MS). In both cases, high triglyceride levels are associated with reduced HDL levels. Chronic kidney disease (CKD) is itself associated with increasing insulin resistance as renal function fails. In both instances, decreased levels of apo A-I and apo A-II are a consequence of increased fractional catabolic rate (FCR), resulting from a predominance of small HDL particles. HDL maturation is impaired in CKD through decreased activity of lecithin:cholesterol acyltransferase (LCAT), and increased cholesterol ester transfer protein (CETP) activity in MS shuttles triglycerides back into HDL, thereby destabilizing it. Whether insulin resistance is entirely responsible for disorders of HDL metabolism in CKD, or whether the process is a result of unrelated pathophysiology, is currently unknown.  相似文献   
43.
Patients with bulimia (binge-purge syndrome) frequently complain that they consume a very restrictive diet to avoid gaining weight. To investigate this claim, 23 hospitalized bulimic patients were assessed daily for body weight, caloric intake, macronutrient diet content, activity measures, and body composition estimates during weight-stable periods. Bulimic patients ate fewer kilocalories per kilogram body weight (22.1 +/- 4.6 kcal/kg) than did age-matched normal women (29.7 +/- 6.5 kcal/kg) but had similar activity levels and body composition. Clinical variables, such as history of laxative abuse, anorexia, or obesity, and physiological characteristics, such as body weight, activity level, or dietary content, could not account for this difference in caloric consumption. Bulimic patients tended to eat a diet lower in fat and higher in protein than did control subjects. These results agree with observations of increased efficiency of caloric utilization in obese patients and support patient complaints of a tendency to gain weight easily.  相似文献   
44.
45.
Stimulation of lymphocytes from motor neurone disease patients by either concanavalin A or PHA was shown to be significantly depressed relative to that from normal controls, as assayed by incorporation of [3H]thymidine or [3H]leucine or by glucose uptake. Corresponding significant differences were not shown by assays based upon incorporation of [3H]uridine or of lactate release. Lymphocytes from 4 out of 14 motor neurone disease patients showed a blastogenic response to membranes from rat spinal cord cells, compared with those from 0 out of 9 normal controls. These results not only suggest the possibility of an impaired cellular immune control in MND patients but also indicate the presence of lymphocytes sensitised specifically to neuronal membrane components.  相似文献   
46.
47.
Forty elderly patients with basicervical and pertrochanteric fractures were managed with uniplanar AO external fixator under regional anaesthetic block of the femoral nerve and lateral cutaneous nerve of the thigh from April 2003 to March 2006. The mean age of the patients was 67.9 ± 5.5 years. External fixator application was performed under radiological control after closed reduction had been obtained. Comorbid factors, duration of surgery, duration of hospitalisation, complications, walking ability, time to union and mortality rate were recorded. Patients were followed up for a mean period of 12 ± 4.5 months. Superficial pin tract infection occurred in 13 patients, healing in varus >10° and with shortening >2 cm occurred in six patients, and one patient suffered a spontaneous ipsilateral femoral neck fracture after removal of the fixator. The mean time for union was 10.4 ± 1.2 weeks. Rapid union rate and minor complications obtained in the present study are comparable to those obtained with standard internal fixation techniques. Minimal intraoperative blood loss, short operative time and early patient mobilisation are advantages signifying uniplanar external fixator application under regional anaesthetic block to be a viable option in treatment of basicervical and pertrochanteric fractures in high-risk elderly patients.  相似文献   
48.
49.
The Sixth Epilepsy Research Foundation workshop, held in Oxford in March 2006, brought together basic scientists, geneticists, epidemiologists, statisticians, pharmacologists and clinicians to consider progress, issues and strategies for harnessing genetics to improve the understanding and treatment of the epilepsies. General principles were considered, including the fundamental importance of clear study design, adequate patient numbers, defi ned phenotypes, robust statistical data handling, and follow-up of genetic discoveries. Topics where some progress had been made were considered including chromosomal abnormalities, neurodevelopment, hippocampal sclerosis, juvenile myoclonic epilepsy, focal cortical dysplasia and pharmacogenetics. The ethical aspects of epilepsy genetics were reviewed. Principles and limitations of collaboration were discussed. Presentations and their matched discussions are produced here. There was optimism that further genetic research in epilepsy was not only feasible, but might lead to improvements in the lives of people with epilepsy.  相似文献   
50.
The molecular events responsible for controlling cell growth and development, as well as their coordinate interaction is only beginning to be revealed. At the basis of these controlling events are hormones, growth factors and mitogens which, through transmembrane signalling trigger an array of cellular responses, initiated by receptor-associated tyrosine kinases, which in turn either directly or indirectly mediate their effects through serine/threonine protein kinases. Utilizing the obligatory response of activation of protein synthesis in cell growth and development, we describe efforts to work backwards along the regulatory pathway to the receptor, identifying those molecular components involved in modulating the rate of translation. We begin by describing the components and steps of protein synthesis and then discuss in detail the regulatory pathways involved in the mitogenic response of eukaryotic cells and during meiotic maturation of oocytes. Finally we discuss possible future work which will further our understanding of these systems.  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