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   170398篇
  免费   10272篇
  国内免费   431篇
耳鼻咽喉   2229篇
儿科学   5540篇
妇产科学   3571篇
基础医学   23155篇
口腔科学   7604篇
临床医学   12455篇
内科学   38316篇
皮肤病学   4340篇
神经病学   14204篇
特种医学   5351篇
外国民族医学   26篇
外科学   21073篇
综合类   1396篇
现状与发展   1篇
一般理论   60篇
预防医学   17813篇
眼科学   3148篇
药学   10342篇
中国医学   692篇
肿瘤学   9785篇
  2023年   828篇
  2022年   1878篇
  2021年   3638篇
  2020年   2435篇
  2019年   3444篇
  2018年   4849篇
  2017年   3632篇
  2016年   3370篇
  2015年   3957篇
  2014年   5412篇
  2013年   6847篇
  2012年   10676篇
  2011年   11148篇
  2010年   5639篇
  2009年   5066篇
  2008年   8628篇
  2007年   9253篇
  2006年   8557篇
  2005年   8842篇
  2004年   8332篇
  2003年   7606篇
  2002年   5670篇
  2001年   4957篇
  2000年   4952篇
  1999年   4350篇
  1998年   1559篇
  1997年   1294篇
  1996年   1285篇
  1995年   1089篇
  1994年   1088篇
  1993年   988篇
  1992年   2654篇
  1991年   2564篇
  1990年   2342篇
  1989年   2346篇
  1988年   2111篇
  1987年   1967篇
  1986年   1832篇
  1985年   1753篇
  1984年   1260篇
  1983年   1015篇
  1982年   570篇
  1981年   518篇
  1980年   496篇
  1979年   921篇
  1978年   611篇
  1977年   478篇
  1975年   542篇
  1974年   540篇
  1973年   541篇
排序方式: 共有10000条查询结果,搜索用时 281 毫秒
1.
2.
Gestational trophoblastic neoplasia (GTN) patients are treated according to the eight-variable International Federation of Gynaecology and Obstetrics (FIGO) scoring system, that aims to predict first-line single-agent chemotherapy resistance. FIGO is imperfect with one-third of low-risk patients developing disease resistance to first-line single-agent chemotherapy. We aimed to generate simplified models that improve upon FIGO. Logistic regression (LR) and multilayer perceptron (MLP) modelling (n = 4191) generated six models (M1-6). M1, all eight FIGO variables (scored data); M2, all eight FIGO variables (scored and raw data); M3, nonimaging variables (scored data); M4, nonimaging variables (scored and raw data); M5, imaging variables (scored data); and M6, pretreatment hCG (raw data) + imaging variables (scored data). Performance was compared to FIGO using true and false positive rates, positive and negative predictive values, diagnostic odds ratio, receiver operating characteristic (ROC) curves, Bland-Altman calibration plots, decision curve analysis and contingency tables. M1-6 were calibrated and outperformed FIGO on true positive rate and positive predictive value. Using LR and MLP, M1, M2 and M4 generated small improvements to the ROC curve and decision curve analysis. M3, M5 and M6 matched FIGO or performed less well. Compared to FIGO, most (excluding LR M4 and MLP M5) had significant discordance in patient classification (McNemar's test P < .05); 55-112 undertreated, 46-206 overtreated. Statistical modelling yielded only small gains over FIGO performance, arising through recategorisation of treatment-resistant patients, with a significant proportion of under/overtreatment as the available data have been used a priori to allocate primary chemotherapy. Streamlining FIGO should now be the focus.  相似文献   
3.
4.
5.
Neorickettsia helminthoeca (NH), the agent of salmon poisoning disease or canine neorickettiosis (CN), is a bacterial endosymbiont of the nematode Nanophyetus salmincola, and infections are spreading among specific fish‐eating mammalians. This article describes the pathologic and immunohistochemical findings associated with spontaneous NH‐induced infections in dogs from Southern Brazil. The principal pathologic findings were hypertrophy of Peyer patches and lymphadenopathy with lymphocytic proliferation, chronic interstitial pneumonia, and chronic enteritis associated with positive intralesional immunoreactivity to antigens of NH within macrophages and histiocytes. Positive immunoreactivity against canine parvovirus‐2 (CPV‐2) or/and canine distemper virus was not detected in the evaluated intestinal segments or in the samples from the cerebellum and lungs, respectively, from the dogs evaluated. These findings demonstrated that NH was involved in the enteric, pulmonary, and lymphoid lesions herein described, and provide additional information to confirm the occurrence of this bacterial endosymbiont within this geographical location. It is proposed that chronic pneumonia should be considered as a pathologic manifestation of NH‐induced infections. Additionally, our results show that the occurrences of CN seem to be underdiagnosed in Southern Brazil due to the confusion with the incidence of CPV‐2.  相似文献   
6.
7.
8.
Depigmented lesions may occur as postinflammatory sequelae of subacute cutaneous lupus erythematosus (SCLE), leading to great psychosocial impact. A 53‐year‐old male patient presented with post‐SCLE depigmented facial lesions after five years of disease stability. We proposed surgical treatment with melanocyte‐keratinocyte transplantation procedure (MKTP), and after five months the patient achieved 90% repigmentation, without Koebner phenomenon (KP). In theory, KP is a possible complication of MKTP procedure since the preparation of the receptor area involves the use of dermabrasion. In an attempt to avoid it, we suggest to maintain the treatment of the underlying disease and wait for a minimum period of disease stability before the procedure.  相似文献   
9.
10.
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