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   75710篇
  免费   41276篇
  国内免费   10篇
耳鼻咽喉   1481篇
儿科学   4210篇
妇产科学   529篇
基础医学   15395篇
口腔科学   5113篇
临床医学   12222篇
内科学   22773篇
皮肤病学   7453篇
神经病学   13204篇
特种医学   2169篇
外科学   13592篇
综合类   6篇
一般理论   21篇
预防医学   4138篇
眼科学   1217篇
药学   5493篇
中国医学   1011篇
肿瘤学   6969篇
  2023年   34篇
  2022年   41篇
  2021年   1259篇
  2020年   5038篇
  2019年   10812篇
  2018年   10058篇
  2017年   11432篇
  2016年   12071篇
  2015年   11910篇
  2014年   11794篇
  2013年   12251篇
  2012年   3989篇
  2011年   3931篇
  2010年   8856篇
  2009年   5204篇
  2008年   1961篇
  2007年   788篇
  2006年   860篇
  2005年   610篇
  2004年   626篇
  2003年   637篇
  2002年   722篇
  2001年   774篇
  2000年   702篇
  1999年   265篇
  1998年   32篇
  1997年   19篇
  1996年   22篇
  1995年   15篇
  1994年   13篇
  1993年   10篇
  1992年   26篇
  1991年   30篇
  1990年   20篇
  1989年   11篇
  1988年   20篇
  1987年   16篇
  1986年   20篇
  1985年   22篇
  1984年   5篇
  1983年   10篇
  1982年   7篇
  1981年   10篇
  1979年   8篇
  1978年   12篇
  1977年   5篇
  1973年   4篇
  1972年   8篇
  1971年   6篇
  1968年   4篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
Gastric mucormycosis involvement is a rare condition that usually occurs in inmunocompromised patients and frequently has a fatal outcome. We report the case of a 73‐year‐old woman admitted to the intensive care unit with severe bleeding after an acute pulmonary disease. Upper endoscopy disclosed wide and deep necrotic ulcers in the body and fundus of the stomach and greenish exudates with the antrum and the duodenum undamaged. Autopsy revealed an invasive mucormycosis and a severe atheromatosis. Several predisposing factors for mucormycosis infection have been reported until now. We postulate that ischemic gastritis could be a predisposing factor for colonization of zygomycete.  相似文献   
72.
73.
This study examined the relationship between psychological sense of community, social‐support networks, and care‐giver stress and satisfaction among firefighters. No significant gender differences were obtained, but zero‐order correlates demonstrated significant relationships among all four variables. In examining the mediating effects of social‐support satisfaction, partial mediation for psychological sense of community on care‐giver satisfaction was determined, as well as full mediation for psychological sense of community on care‐giver stress. Therefore, firefighters who are satisfied with the support they receive may experience less stress with their care giving than those who experience low levels of support satisfaction. Future studies should assess these relationships more extensively in other areas of civic responsibility among public‐service employees to delineate effective support avenues. © 2004 Wiley Periodicals, Inc. J Comm Psychol 32: 121–126, 2004.  相似文献   
74.
A 3.5‐year‐old intact male American Pit Bull was presented because of urinary incontinence and dysuria. Constipation, followed by diarrhoea, ocular disturbances and finally regurgitation developed over the next 4 years. Autonomic dysfunction was evidenced by clinical presentation, as well as positive ophthalmic pilocarpine test and subnormal Schirmer tear test. Diagnosis, however, was established through histopathological and immunohistochemical examination. Lesions attributable to inflammatory degenerative neuropathy of the autonomic ganglia, which represents one of the various types of human autonomic failure, were detected.  相似文献   
75.
Childhood psoriasis is a disease with manifold clinical presentations which can make the correct diagnosis sometimes difficult. In a female infant, slightly itching, erythematous papules and plaques with discrete scaling spread over large parts of the integument starting from age three months. Histological examination supported the diagnosis of exanthematous infantile psoriasis. Topical treatment with dithranol in petrolatum led to slow clearance of the skin lesions.  相似文献   
76.
The etiology of epidermolysis bullosa acquisita (EBA) is unknown. EBA may be associated with other autoim‐mune systemic diseases; it also has been described in connection with different malignant tumors, showing complete remission after successful treatment of the tumor.In such cases, EBA may be regarded as a paraneo‐plastic dermatosis. We detected a highly differentiated neuroendocrine pancreatic cancer in a 78‐year‐old woman with EBA. Even thought her tumor was completely removed and the patient has been disease‐free for over seven years, a complete regression of her autoimmune bullous dermatosis could not be induced. By using intravenous immunoglobulins in combination with mycophenolate mofetil, further blister formation could be ameliorated.  相似文献   
77.
AIMS: The glutamate decarboxylase gene (GAD2) encodes GAD65, an enzyme catalysing the production of the gamma-aminobutyric acid (GABA) which interacts with neuropeptide Y to stimulate food intake. It has been suggested that in pancreatic islets, GABA serves as a functional regulator of pancreatic hormone release. Conflicting results have been reported concerning the potential impact of GAD2 variation on estimates of energy metabolism. The aim of this study was to elucidate potential associations between the GAD2-243A-->G polymorphism and levels of body mass index (BMI) and estimates of glycaemia. METHODS: Using high-throughput chip-based matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, the GAD2-243A-->G (rs2236418) polymorphism was genotyped in a population-based sample (Inter99) of 5857 middle-aged, unrelated Danish White subjects. RESULTS: The G-allele was associated with modestly lower BMI (P = 0.01). In a case-control study of obesity, the G-allele frequency in 2582 participants with BMI < 25 kg/m2 was 19.5% (18.4-20.6) compared with 17.1% (15.5-18.8) in 968 participants having BMI > or = 30 kg/m2 (P = 0.03), odds ratio 0.9 (0.7-1.0). Of the 5857 subjects, GG carriers had lower fasting plasma glucose levels (mmol/l) [AA (n = 3859) 5.6 +/- 0.8; AG (n = 1792) 5.5 +/- 0.8; GG (n = 206) 5.5 +/- 0.8, P = 0.008] and lower 30-min oral glucose tolerance test (OGTT)-related plasma glucose levels (AA 8.7 +/- 1.9; AG 8.6 +/- 1.9; GG 8.6 +/- 2.0, P = 0.04), adjusted for sex, age and BMI. Analysing subjects who were both normoglycaemic and glucose tolerant (n = 4431) GG carriers still had lower fasting plasma glucose concentrations: AA (n = 2895) 5.3 +/- 0.4; AG (n = 1383) 5.3 +/- 0.4; GG (n = 153) 5.2 +/- 0.4 (P = 9.10(-5)). CONCLUSION: The present study suggests that the GAD2-243A-->G polymorphism in a population of middle-aged White people associates with a modest reduction in BMI and fasting and OGTT-related plasma glucose levels.  相似文献   
78.
79.
We consider the problem of detection of modifier genes that lead to variations in a disease‐related continuous variable (DRCV), such as the age of onset or a measure of disease severity, in a strategy of candidate genes. We propose a novel method, the ordered transmission disequilibrium test (OTDT), to test for a relation between the clinical heterogeneity expressed by a DRCV and marker genotypes of a candidate gene. The OTDT applies to trio families with one patients and his parents, all three genotyped at a bi‐allelic marker M. The OTDT aims to find a critical value of the DRCV which separates the sample of families in two subsamples in which the transmission rates are significantly different. We investigate the power of the method by simulations under various genetic models and covariate distributions and compare it with a linear regression analysis. Genet. Epidemiol. 2008. ©2008 Wiley‐Liss, Inc.  相似文献   
80.
The main goal of the present work was to longitudinally examine consequences of long‐term moderately elevated levels of stress for various health outcomes. To address this issue, data covering 10 years was used from the ongoing Swedish population‐based prospective Betula Study. Based on the ratings on a validated self‐reported stress scale, matched subsamples between 40 and 65 years of age were divided into a high (n = 137) and low (n = 211) stress group. The reported incidence of cardiovascular, diabetes, psychiatric, tumour and musculoskeletal diseases was assessed 5 and 10 years after baseline (baseline = 1993–1995) without contaminating effects of past health history. The incidence of diseases 5 years after baseline assessment showed no differences between the groups. After 10 years, there was a significantly higher incidence of psychiatric diseases, mainly depression in the high‐stress group as well as a significant effect for tumours, although the number of cases was low. Although moderately elevated stress level may have a possible impact on psychiatric diseases especially depression and some tumours, it seems that prolonged moderate stress does not appear to be harmful to other stress‐related diseases. Copyright © 2007 John Wiley & Sons, Ltd.  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