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   724篇
  免费   50篇
  国内免费   3篇
耳鼻咽喉   2篇
儿科学   15篇
妇产科学   13篇
基础医学   73篇
口腔科学   25篇
临床医学   108篇
内科学   166篇
皮肤病学   38篇
神经病学   33篇
特种医学   89篇
外国民族医学   1篇
外科学   55篇
综合类   37篇
预防医学   34篇
眼科学   2篇
药学   45篇
中国医学   1篇
肿瘤学   40篇
  2022年   19篇
  2021年   15篇
  2020年   10篇
  2019年   15篇
  2018年   16篇
  2017年   14篇
  2016年   13篇
  2015年   17篇
  2014年   23篇
  2013年   25篇
  2012年   15篇
  2011年   19篇
  2010年   32篇
  2009年   30篇
  2008年   13篇
  2007年   19篇
  2006年   20篇
  2005年   12篇
  2004年   11篇
  2003年   14篇
  2002年   12篇
  2001年   9篇
  2000年   7篇
  1999年   8篇
  1998年   22篇
  1997年   14篇
  1996年   24篇
  1995年   18篇
  1994年   27篇
  1993年   28篇
  1992年   15篇
  1990年   10篇
  1989年   18篇
  1988年   17篇
  1987年   12篇
  1986年   11篇
  1985年   15篇
  1983年   10篇
  1982年   11篇
  1981年   9篇
  1980年   11篇
  1979年   11篇
  1978年   7篇
  1977年   8篇
  1975年   6篇
  1957年   9篇
  1955年   6篇
  1954年   6篇
  1949年   8篇
  1948年   8篇
排序方式: 共有777条查询结果,搜索用时 0 毫秒
11.
12.
Epilepsy surgery has emerged as an important option in the treatment of children with epilepsy that is refractory to antiepileptic drug management. The cornerstone of successful surgery is accurate localization of the brain region of seizure onset. Traditional techniques of seizure onset localization, e.g. surface electroencephalography (EEG) recording and magnetic resonance imaging (MRI), allow accurate localization in a significant number of patients. When the focus of seizure onset is not apparent from these non-invasive techniques, other methods of localization, e.g. intracranial EEG recording, may be needed before resection of the focus. Single-photon emission computed tomography (SPECT) is a nuclear medicine blood-flow technique that has been used to identify a region of epileptogenic brain associated with low blood flow in the resting state (interictal SPECT) or increased blood flow at the time of seizure activity (ictal SPECT). This report describes the validation and utility of a computer-assisted method of subtracting the interictal from the ictal SPECT scans and co-registering the difference image on the MRI. This method, called subtraction ictal SPECT co-registered on MRI (SISCOM), is used in guiding the location and the extent of intracranial electrode implantation, or in obviating the need for the implantation in some cases.  相似文献   
13.
Female circumcision is a traditional practice common in African countries. It involves partial or total removal of external female genitalia. It has led to many complications, in particular, the scarring of the external genitalia. The consequence is a very narrow introitus making the intracavitary brachytherapy treatment component difficult when these women develop cancer of cervix. We present two such cases from our institution. Our aim is to make the radiation and gynecological oncologists, both in developed and developing countries, aware of this practice and the problems they can encounter in the management of such cases. Intracavitary brachytherapy is an important component in the potentially curative role of radiation therapy for cervical cancer. Every effort should be made to ensure that the sequelae of genital mutilation does not deprive these women of the same standard of care as the general population.  相似文献   
14.
Acute otomastoiditis and its complications: role of CT   总被引:2,自引:0,他引:2  
Acute bacterial (suppurative) otomastoiditis responds to antibiotic treatment; radiologic study is required only when there is clinical suggestion of coalescent mastoiditis, intracranial complications, or an underlying chronic disease. Computed tomography (CT) is the method of choice for evaluating otogenic intra- or extra-cranial complications. CT scans can show stages of disease progression when infection has spread by way of soft tissue, blood, and bone pathways into the dural venous sinuses, meninges, labyrinth, facial nerves, epidural and other intracranial spaces. When there is clinical suggestion of acute coalescent mastoiditis, a CT scan of the temporal bone can confirm the presence of rarefying osteitis, coalescence of the air cells, and subperiosteal abscess.  相似文献   
15.
Loss-of-function variants in ANKRD11 were identified as the cause of KBG syndrome, an autosomal dominant syndrome with specific dental, neurobehavioural, craniofacial and skeletal anomalies. We present the largest cohort of KBG syndrome cases confirmed by ANKRD11 variants reported so far, consisting of 20 patients from 13 families. Sixteen patients were molecularly diagnosed by Sanger sequencing of ANKRD11, one familial case and three sporadic patients were diagnosed through whole-exome sequencing and one patient was identified through genomewide array analysis. All patients were evaluated by a clinical geneticist. Detailed orofacial phenotyping, including orthodontic evaluation, intra-oral photographs and orthopantomograms, was performed in 10 patients and revealed besides the hallmark feature of macrodontia of central upper incisors, several additional dental anomalies as oligodontia, talon cusps and macrodontia of other teeth. Three-dimensional (3D) stereophotogrammetry was performed in 14 patients and 3D analysis of patients compared with controls showed consistent facial dysmorphisms comprising a bulbous nasal tip, upturned nose with a broad base and a round or triangular face. Many patients exhibited neurobehavioural problems, such as autism spectrum disorder or hyperactivity. One-third of patients presented with (conductive) hearing loss. Congenital heart defects, velopharyngeal insufficiency and hip anomalies were less frequent. On the basis of our observations, we recommend cardiac assessment in children and regular hearing tests in all individuals with a molecular diagnosis of KBG syndrome. As ANKRD11 is a relatively common gene in which sequence variants have been identified in individuals with neurodevelopmental disorders, it seems an important contributor to the aetiology of both sporadic and familial cases.  相似文献   
16.
17.
A facile single-step synthesis was performed to cross-link chitosan with thiocarbohydrazide to yield thiocarbohydrazide-chitosan (TC-Cht) which was for the first time evaluated as an inhibitor for corrosion of stainless steel in 3.5% NaCl solution. A comprehensive electrochemical analysis employing electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PDP), and cyclic voltammetry (CV) was undertaken and showed that the TC-Cht acts by adsorption on the steel surface and exhibits mixed type behavior with predominantly cathodic nature. The adsorption of TC-Cht molecules on the surface of stainless steel followed the Langmuir isotherm. The TC-Cht showed a high inhibition efficiency of >94% at 500 mg L?1 concentration. Surface investigation using SEM and EDX supported the inhibitor adsorption on the steel surface.  相似文献   
18.
19.
20.
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