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   879篇
  免费   42篇
  国内免费   33篇
耳鼻咽喉   9篇
儿科学   25篇
妇产科学   9篇
基础医学   73篇
口腔科学   72篇
临床医学   77篇
内科学   196篇
皮肤病学   6篇
神经病学   80篇
特种医学   117篇
外科学   73篇
综合类   28篇
预防医学   30篇
眼科学   22篇
药学   70篇
中国医学   5篇
肿瘤学   62篇
  2023年   3篇
  2022年   10篇
  2021年   17篇
  2020年   4篇
  2019年   7篇
  2018年   13篇
  2017年   11篇
  2016年   13篇
  2015年   9篇
  2014年   27篇
  2013年   35篇
  2012年   34篇
  2011年   36篇
  2010年   28篇
  2009年   43篇
  2008年   63篇
  2007年   90篇
  2006年   62篇
  2005年   37篇
  2004年   26篇
  2003年   20篇
  2002年   21篇
  2001年   22篇
  2000年   16篇
  1999年   31篇
  1998年   16篇
  1997年   18篇
  1996年   19篇
  1995年   17篇
  1994年   20篇
  1993年   14篇
  1992年   13篇
  1991年   16篇
  1990年   8篇
  1989年   19篇
  1988年   13篇
  1987年   17篇
  1986年   9篇
  1985年   13篇
  1984年   7篇
  1983年   3篇
  1982年   3篇
  1981年   11篇
  1979年   9篇
  1977年   5篇
  1976年   5篇
  1975年   5篇
  1968年   4篇
  1967年   2篇
  1966年   2篇
排序方式: 共有954条查询结果,搜索用时 31 毫秒
1.
2.
Septic arthritis of the temporomandibular joint (TMJ) is infrequently reported. We present a case of septic arthritis of the TMJ following the extraction of the left upper second molar that occurred 1 week before beginning of symptoms. No evident predisposing factors were detected. Arthroscopic diagnosis of septic arthritis, lysis and lavage, and capsular stretch were performed. Cultures taken from the TMJ space grew Streptococcus sp. After 1 month of antimicrobial therapy the patient was asymptomatic and mandibular function was normal. Literature related to septic arthritis of TMJ and its treatment was reviewed. Different surgical procedures are available to treat this condition. Arthroscopy should be preferred as initial treatment on account of the possibility of drainage and accurate lavage under direct visualization of joint space, at the same time allowing confirmation of diagnostic hypotheses. Improving joint mobility with lysis of adhesions and capsular stretch in an early stage of disease may be helpful in stopping the fibrosis process.  相似文献   
3.
4.
Neuroimaging in Pineal Tumors   总被引:4,自引:0,他引:4  
F Reis  MD  AV Faria  MD  PhD  VA Zanardi  MD  PhD  JR Menezes  MD  F Cendes  MD  PhD  LS Queiroz  MD  PhD 《Journal of neuroimaging》2006,16(1):52-58
BACKGROUND AND PURPOSE: The authors report radiological findings in 11 tumors in the pineal region, which were histologically diagnosed as germinomas, pineocytomas pineoblastomas, ependymomas, teratomas, and astrocytomas. METHODS: Computed tomography (CT) was performed in seven patients and magnetic resonance imaging (MRI) was performed in all patients. RESULTS: CT showed a solid or solid/cystic mass with variable contrast enhancement. MRI showed a heterogeneous mass, with hypointense signal on T1 and iso/hyperintense signal on T2-weighted images (WI) and gadolinium enhancement. Extension to adjacent structures occurred in five patients and spread through the cerebral spinal fluid (CSF) in two. CONCLUSIONS: Pineal region tumors have no pathognomonic imaging pattern. MRI and CT are complementary in diagnosis and are important to determine localization, extension, and meningeal spread.  相似文献   
5.
PURPOSE: The aim of this study was to evaluate skeletal stability after double jaw surgery for correction of skeletal Class III malocclusion to assess if there were any differences between resorbable plate and screws and titanium rigid fixation of the maxilla. PATIENTS AND METHODS: Twenty-two Class III patients had bilateral sagittal split osteotomy for mandibular setback stabilized with rigid internal fixation. Low level Le Fort I osteotomy for maxillary advancement was stabilized with conventional titanium plate and screws in 12 patients (group 1) and with resorbable plate and screws in 10 patients (group 2). Lateral cephalograms were taken before surgery, immediately postoperatively, 8 weeks after surgery, and 1 year postoperatively. RESULTS: Before surgery both groups were balanced with respect to linear and angular measurements of craniofacial morphology. One year after surgery, maxillary stability was excellent in both groups. In group 1 no significant correlations were found between maxillary advancement and relapse. In group 2, significant correlations were found between maxillary advancement and relapse at A point and posterior nasal spine. No significant differences in postoperative skeletal and dental stability between groups were observed. CONCLUSION: Surgical correction of Class III malocclusion after combined maxillary and mandibular procedures appears to be a fairly stable procedure for maxillary advancements up to 5 mm independently from the type of fixation used to stabilize the maxilla. Resorbable devices should be used with caution for bony movements of greater magnitude until their usefulness is evaluated in studies with large maxillary advancements.  相似文献   
6.
The present study reviews the literature concerning the surgical treatment of Aspergillus mycetoma (AM) in the last 20 years to identify a gold standard surgical technique. Aspergillus mycetoma of the maxillary sinus, or mycetoma (fungus ball), is a noninvasive or extramucosal mycotic infection. Surgical removal of the sinus fungal masses to ensure drainage and aeration is performed using the traditional Caldwell-Luc (CL) procedure or endoscopic sinus surgery (ESS). Results of this review suggest that the gold standard surgical technique for AM is ESS with middle meatal antrostomy. General or local antifungal drugs are not indicated. Combined approach with an intraoral surgical access from the anterolateral wall of the maxillary sinus has to be reserved for selected cases in which ESS doesn't permit complete extraction of all fungal concretions or foreign bodies. The CL procedure should be avoided, because it has detrimental consequences for sinus physiology.  相似文献   
7.
8.
We describe here a culture method which allows the growth of dissociated mouse retinal neurons and photoreceptors in chemically defined medium. Neural retinas from 2-day-old C57/BL mice were dissected from other ocular tissues, including the pigment epithelium, and dissociated into a cell suspension after brief trypsination. Most cells attached as single, unaggregated units to substrata pretreated with polyornithine and the neurite-promoting factor (PNPF). The cells were cultured in serum-free, high pyruvate Dulbecco's modified Eagle's medium containing chemically defined supplements. Under these conditions, onset of cell process development was rapid, giving rise to extensive neurite networks. Three morphologically distinct cell types were apparent during the first week in vitro. Some cells retained a circular outline and failed to produce processes, while 50-60% of the cells developed as multipolar neurons showing a large cell body and several neurites. Approximately 90% of these cells reacted with an amacrine cell-specific monoclonal antibody. Some 30% of the cultured cells expressed phenotypic properties characteristic of rod photoreceptors, including a small cell body, an apical cilium, a short neurite with a spherule-like terminal body, and immunoreactivity with antibodies against opsin as well as a rod cell-specific monoclonal antibody. No further signs of outer segment differentiation were observed in these cells. Non-neuronal "flat" cells, which represented less than 0.5% of the total cell number, reacted with an antibody against the glial fibrillary acidic protein. The number of neurons and photoreceptors remained relatively stable during the first 4-7 days in vitro. During the second week in culture, however, there was specific degeneration of greater than 90% of the photoreceptor cells, while less than 20% of the multipolar neurons were similarly affected. Consequently, in addition to providing a system for studying the differentiation of retinal neurons and photoreceptors, the specific degeneration of photoreceptors in these mouse retinal cell cultures makes this system ideal for investigating factors influencing photoreceptor survival.  相似文献   
9.
A total of 474 histologically proved Lung Cancers (LC) were evaluated by Conventional Radiology (CR) and Computed Tomography (CT) in order to assess the role of these two diagnostic modalities in the staging of LC. In 196/474 LC it was possible also to refer, for the evaluation of the diagnostic reliability, to the surgical control. The CR features of LC both at stage III (13% of the global series) and at stage I-peripheral T1 (16% of the global series) presented very high positive and negative predictive values (90% and 95%, retrospectively); in these cases it was considered useless to perform CT. The CT grading showed a high negative predictive value in excluding stage III caused respectively by grade T3 (91.5%) and grade N2 (93.5%). As to the staging, the CT assessment of the stage I and II showed a high predictive value (91.5%). On the other hand, the CT assessment of stage III presented an unsatisfactory predictive value (71%), due to the low predictive value in grade T3 (71.5%), poor in grade N2 (57.5%). The increase of the value threshold mediastinal adenopathies from 1 to 2 cm, leads to a great improvement of this predictive value (92%). The CT reliability was matched with the two different surgical "philosophies" (non aggressive or aggressive); surgery was excluded or performed according to the presence of omo-lateral mediastinal adenopathy. A correct advice to perform surgery was achieved in 33.5% (non aggressive "philosophy") and 43.8% (aggressive "philosophy") of cases; surgery was correctly excluded respectively in 49.6% and 45.9%. The resort to mediastinoscopy was advised in 7.8% and 1.3% of the cases respectively. In both "philosophies" the error of under-staging was lower (2.5%), than that of over-staging (6.6%).  相似文献   
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