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   26701篇
  免费   1839篇
  国内免费   104篇
耳鼻咽喉   413篇
儿科学   743篇
妇产科学   592篇
基础医学   3800篇
口腔科学   2102篇
临床医学   2074篇
内科学   5526篇
皮肤病学   575篇
神经病学   1958篇
特种医学   634篇
外科学   3113篇
综合类   266篇
一般理论   13篇
预防医学   3240篇
眼科学   354篇
药学   1800篇
中国医学   219篇
肿瘤学   1222篇
  2023年   277篇
  2022年   460篇
  2021年   1106篇
  2020年   714篇
  2019年   938篇
  2018年   1150篇
  2017年   778篇
  2016年   800篇
  2015年   952篇
  2014年   1300篇
  2013年   1520篇
  2012年   2181篇
  2011年   2436篇
  2010年   1277篇
  2009年   992篇
  2008年   1640篇
  2007年   1593篇
  2006年   1318篇
  2005年   1201篇
  2004年   1017篇
  2003年   880篇
  2002年   780篇
  2001年   486篇
  2000年   431篇
  1999年   370篇
  1998年   140篇
  1997年   101篇
  1996年   90篇
  1995年   59篇
  1994年   64篇
  1993年   51篇
  1992年   165篇
  1991年   146篇
  1990年   104篇
  1989年   113篇
  1988年   102篇
  1987年   72篇
  1986年   93篇
  1985年   72篇
  1984年   67篇
  1983年   58篇
  1982年   34篇
  1980年   34篇
  1979年   46篇
  1978年   31篇
  1976年   33篇
  1973年   28篇
  1971年   36篇
  1969年   34篇
  1967年   28篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
2.
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   
3.
4.
We present a 6‐year‐old girl with skin hyperpigmentation, leukoplakia, and onychodystrophy, the classic mucocutaneous triad usually associated with dyskeratosis congenita. The patient also had premature graying of the hair, bone marrow failure, hepatitis, exudative retinopathy, osteopenia with multiple long bone fractures, and intracranial calcifications and brain cysts. Coats plus syndrome is a rare disease with a clinical and genetic overlap with dyskeratosis congenita. This disease is reviewed, with a focus on the pathogenesis of the genetic anomalies and its background as a telomere biology disorder.  相似文献   
5.
6.
7.
8.
Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital condition. It responds well to early diagnosis and treatment, but otherwise the prognosis is poor. We present our case series of 12 patients (mean age, 2 ± 2.58 yr; age range, 2 mo–8 yr), emphasizing the diagnostic process and discussing our surgical results. The diagnosis of ALCAPA should be suspected in infants who have dilated cardiomyopathy with electrocardiographic changes that suggest ischemia, and in older children who have isolated mitral regurgitation. When clinical suspicion is high, the results of 2-dimensional echocardiography combined with color-flow Doppler studies in expert hands can establish the diagnosis, thus avoiding angiography in critically ill infants. The treatment of choice in our patients was transfer and reimplantation of the left coronary artery onto the ascending aorta. There were 2 deaths: both were infants in extremis who underwent emergency surgery. An older child with severe ventricular dysfunction was given mechanical ventricular assistance and then heart transplantation. As of this report, all 10 survivors remained well and asymptomatic.  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