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   39639篇
  免费   2069篇
  国内免费   141篇
耳鼻咽喉   521篇
儿科学   2559篇
妇产科学   696篇
基础医学   4734篇
口腔科学   1108篇
临床医学   2857篇
内科学   7121篇
皮肤病学   1116篇
神经病学   2344篇
特种医学   1176篇
外科学   5949篇
综合类   1273篇
一般理论   17篇
预防医学   2015篇
眼科学   1423篇
药学   3974篇
  1篇
中国医学   349篇
肿瘤学   2616篇
  2023年   326篇
  2022年   955篇
  2021年   1598篇
  2020年   878篇
  2019年   970篇
  2018年   1371篇
  2017年   1001篇
  2016年   1322篇
  2015年   1325篇
  2014年   1955篇
  2013年   2215篇
  2012年   3105篇
  2011年   3025篇
  2010年   1817篇
  2009年   1428篇
  2008年   2031篇
  2007年   2057篇
  2006年   1874篇
  2005年   1660篇
  2004年   1545篇
  2003年   1314篇
  2002年   1125篇
  2001年   772篇
  2000年   706篇
  1999年   588篇
  1998年   263篇
  1997年   212篇
  1996年   218篇
  1995年   184篇
  1994年   154篇
  1993年   130篇
  1992年   349篇
  1991年   335篇
  1990年   357篇
  1989年   329篇
  1988年   285篇
  1987年   241篇
  1986年   234篇
  1985年   228篇
  1984年   174篇
  1983年   122篇
  1982年   68篇
  1981年   75篇
  1980年   69篇
  1979年   109篇
  1978年   71篇
  1977年   87篇
  1976年   65篇
  1973年   62篇
  1971年   60篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
61.
Two children out of three siblings of a family presented with tiredness, fatigue, and breathlessness for more than 6 months. Examination of peripheral blood smear, bone marrow aspirate, and a positive acidified serum test (HEMPAS) revealed these children to be a case of congenital dyserythropoietic anemia type II. This case is reported because of its rarity.  相似文献   
62.
Editorial     
Evidence-Based Integrative Medicine -  相似文献   
63.
64.
Community-acquired viral respiratory tract infections (RTI) in lung transplant recipients may have a high rate of progression to pneumonia and can be a trigger for immunologically mediated detrimental effects on lung function. A cohort of 100 patients was enrolled from 2001 to 2003 in which 50 patients had clinically diagnosed viral RTI and 50 were asymptomatic. All patients had nasopharyngeal and throat swabs taken for respiratory virus antigen detection, culture and RT-PCR. All patients had pulmonary function tests at regular intervals for 12 months. Rates of rejection, decline in forced expiratory volume (L) in 1 s (FEV-1) and bacterial and fungal superinfection were compared at the 3-month primary endpoint. In the 50 patients with RTI, a microbial etiology was identified in 33 of 50 (66%) and included rhinovirus (9), coronavirus (8), RSV (6), influenza A (5), parainfluenza (4) and human metapneumovirus (1). During the 3-month primary endpoint, 8 of 50 (16%) RTI patients had acute rejection versus 0 of 50 non-RTI patients (p=0.006). The number of patients experiencing a 20% or more decline in FEV-1 by 3 months was 9 of 50 (18%) RTI versus 0 of 50 non-RTI (0%) (p=0.003). In six of these nine patients, the decline in FEV-1 was sustained over a 1-year period consistent with bronchiolitis obliterans syndrome (BOS). Community-acquired respiratory viruses may be associated with the development of acute rejection and BOS.  相似文献   
65.
This review of the current scenario of celiac disease (CD) in India covers both pediatric and adult CD. CD is primarily reported from northern India with isolated case reports from the rest of the country. CD cases among Indian children are associated with multiple DR3-DQ2 haplotypes. Delay in diagnosis is contributed by multiple factors including atypical presentations. Use of serological tests, IgA EMA and anti-tTG antibodies, along with modified ESPGHAN criteria provides a definitive diagnosis of CD. Dietary management is often difficult due to non-availability of labeled and marketed gluten-free foods. A majority of children with CD show normalization of nutrition, substantial improvement in growth parameters and attainment of healthy percentile curves on gluten-free diet. Small bowel histology remarkably improves but does not normalize even after 2-3 years on gluten-free diet. The true burden of the disease should be addressed by large epidemiological studies.  相似文献   
66.
We report respiratory obstruction following surgery in the sitting position with tracheal intubation and placement of a transesophageal echocardiography probe. Obstruction was due to pharyngeal oedema, which resolved with 24 hours. The mechanisms of this complication are discussed.  相似文献   
67.
The authors report a 50-year-old man with progressive left hemispheric atrophy, cognitive decline, infrequent seizures, and spells suggestive of complicated migraine. They discuss the association between migraine and cerebral hemiatrophy and suggest that the spectrum of acquired cerebral hemiatrophy may be broader than what has been commonly recognized.  相似文献   
68.
Despite the common occurrence of pleomorphic adenoma of major salivary glands, intranasal pleomorphic adenoma are rare. We present a ease of pleomorphic adenoma of the nasal septum along with a brief review of literature. The histological nature of this lesion in comparison to other salivary gland tumours and the importance of an accurate diagnosis has been stressed.  相似文献   
69.
BACKGROUND: The advantage of 4-field radiation to the pelvis is that the use of lateral portals spares a portion of the small bowel anteriorly and rectum posteriorly. The standard lateral portals defined in textbooks are not always adequate especially in advanced cancer cervix. METHODS: An analysis was done to determine adequacy of margins of standard lateral pelvic portals with CECT defined tumor volumes. The study included 40 patients of FIGO stage IIB and IIIB treated definitively for cancer cervix between 1998 and 2000. An inadequate margin was defined if the cervical growth and uterus were not encompassed by the 95% isodose. RESULTS: An inadequate posterior margin was common with bulky disease (P = 0.06) and with retroverted uterus (P = 0.08). Menopausal status, FIGO stage, associated myoma, and age were of no apparent prognostic significance. Bulk retained significant on multivariate analysis. An inadequate anterior margin was common in premenopausal (P = 0.01); anteverted uterus (P = 0.02); associated myoma (P = 0.01); and younger patients (P = 0.03). It was not influenced by bulk or stage. Menopausal status and associated myoma retained significant on multivariate analysis. CONCLUSION: Without the knowledge of precise tumor volume, the 4-field technique with standard portals is potentially risky as it may under dose the tumor through lateral portals and the standard AP/ PA portals are a safer option.  相似文献   
70.
OBJECTIVES: To evaluate the efficacy of oral lycopene therapy in patients with oral submucous fibrosis and to compare these effects with a placebo. STUDY DESIGN: Fifty-eight patients with oral submucous fibrosis formed the population for the study and were randomly divided into 3 groups, evaluated weekly over a 2-month period. Patients of group A (n = 21) received 16 mg of lycopene, those of group B (n = 19) received 16 mg of lycopene along with biweekly intralesional steroid injections, and those of group C (n = 18) were given a placebo. Paired and unpaired t tests were used for statistical evaluation. RESULTS: Mouth-opening values for the patients showed an average increase of 3.4 mm, 4.6 mm, and 0.0 mm for patients in groups A, B, and C, respectively. These values were statistically found to be highly significant. CONCLUSIONS: The observed effects suggest that lycopene can and should be used as a first line of therapy in the initial management of oral submucous fibrosis.  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