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   1277篇
  免费   78篇
  国内免费   3篇
耳鼻咽喉   31篇
儿科学   38篇
妇产科学   40篇
基础医学   156篇
口腔科学   6篇
临床医学   108篇
内科学   307篇
皮肤病学   20篇
神经病学   69篇
特种医学   58篇
外科学   136篇
综合类   21篇
一般理论   3篇
预防医学   73篇
眼科学   48篇
药学   139篇
中国医学   10篇
肿瘤学   95篇
  2023年   20篇
  2022年   27篇
  2021年   33篇
  2020年   19篇
  2019年   36篇
  2018年   31篇
  2017年   33篇
  2016年   40篇
  2015年   27篇
  2014年   51篇
  2013年   47篇
  2012年   73篇
  2011年   88篇
  2010年   46篇
  2009年   52篇
  2008年   79篇
  2007年   78篇
  2006年   74篇
  2005年   51篇
  2004年   46篇
  2003年   48篇
  2002年   38篇
  2001年   21篇
  2000年   19篇
  1999年   23篇
  1998年   9篇
  1997年   9篇
  1996年   8篇
  1995年   7篇
  1994年   8篇
  1993年   5篇
  1992年   17篇
  1991年   28篇
  1990年   14篇
  1989年   20篇
  1988年   19篇
  1987年   15篇
  1986年   12篇
  1985年   11篇
  1984年   9篇
  1983年   7篇
  1982年   3篇
  1981年   5篇
  1979年   5篇
  1978年   4篇
  1976年   5篇
  1974年   6篇
  1973年   8篇
  1972年   4篇
  1971年   6篇
排序方式: 共有1358条查询结果,搜索用时 12 毫秒
91.
92.
Abstract: Whipple's disease is a very rare chronic multisystemic bacterial disease characterized by diarrhea, malabsorption, fever, and polyarthritis. Ocular manifestations occur very rarely. Previous reports have suggested that the use of immunosuppressive drugs appears to accelerate or exacerbate the clinical course of Whipple's disease; however, the illness has yet to be reported in the setting of transplantation. Herein, we describe what we believe is the first reported case of Whipple's disease after transplantation. The patient is a 51‐year‐old woman who developed progressive visual floaters and blurring of vision 30 years after living‐related kidney transplantation for an autosomal‐dominant polycystic kidney disease. Her allograft was functioning well on maintenance immunosuppressive therapy with azathioprine and prednisone when she developed visual abnormalities. Transient weight loss, gastrointestinal symptoms, and migratory polyarthralgia predated the onset of ocular disease by several years. The diagnosis of Whipple's bilateral vitreitis and chorioretinitis was confirmed by polymerase chain reaction analysis demonstrating Tropheryma whipplei nucleic acid in vitreous fluid and peripheral blood sample as well as by demonstration of the bacilli by cytopathology. Intraocular vancomycin, intravenous ceftriaxone, and prolonged course of oral trimethoprim‐sulfamethoxazole therapy led to clinical improvement and recovery of visual acuity.  相似文献   
93.
A rare case of primary tuberculosis of bilateral submandibular salivary glands is presented with review of relevant literature. The patient was managed on conservative therapy.  相似文献   
94.
95.
Perspective: three-dimensional imaging of the musculoskeletal system   总被引:2,自引:0,他引:2  
An evaluation of musculoskeletal disorders in 202 patients using three-dimensional CT displays has revealed the usefulness of the technique, especially in patients with fractures of skeletal areas with complex anatomy, articular disorders of the hip, and spinal stenosis. In some cases, plastic models of diseased areas have been created from the CT data and are reasonably accurate, providing a graphic representation of the disease and the ability to perform rehearsal surgery. A preliminary investigation of three-dimensional displays of MR images indicates that the technique is feasible, although its clinical practicality requires further analysis.  相似文献   
96.
A family of 7-(trifluoromethyl)-4-aminoquinolines that are hypotensive agents and that act by a novel sympatholytic mechanism is described. Structure-activity relationships in this series have been elucidated. Some of the more potent hypotensives were evaluated for safety in the mouse. A candidate, 1-[(4-fluorophenyl)sulfonyl]-4-[4-[[7-(trifluoromethyl)-4- quinolinyl]amino]benzoyl]piperazine hydrochloride (losulazine hydrochloride) has been selected for clinical development. Losulazine hydrochloride is a hypotensive agent in the rat, cat, and dog. At acute effective hypotensive doses, it does not block the response of the sympathetic nervous system to stimuli. Both animal pharmacology and clinical experience suggest that losulazine hydrochloride may be free of the clinically limiting side effects that often plague compounds that decrease blood pressure by interfering with autonomic neurogenic function.  相似文献   
97.

Purpose

The present work was aimed at the development of prospective positron emission tomography (PET) agents for infection imaging. Towards this aim, ubiquicidin (UBI) fragments conjugated with the macrocyclic NODAGA chelator were radiolabeled with Ga-68 and evaluated.

Procedures

Conformations of custom synthesized NODAGA-UBI (29–41) and NODAGA-UBI (31–38) conjugates were compared with UBI (29–41) by circular dichroism (CD) spectroscopy. Optimization of labeling of NODAGA conjugates of UBI peptides with Ga-68 was performed and quality control analysis was carried out by chromatography techniques. In vitro uptake of [68Ga] NODAGA-UBI (29–41) and [68Ga]NODAGA-UBI (31–38) was studied in Staphylococcus aureus cells. In vivo distribution of [68Ga]GaCl3 and [68Ga]NODAGA-UBI complexes was performed in normal Swiss mice.

Results

Conformations of NODAGA-UBI (29–41) and NODAGA-UBI (31–38) conjugates were found to be similar to UBI (29–41). NODAGA-UBI conjugates could be consistently labeled with Ga-68 in high radiochemical yields (>95 %) with high radiochemical purity (>95 %). [68Ga]NODAGA-UBI (29–41) and [68Ga]NODAGA-UBI (31–38) complexes showed retention time of 14 and 14.5 min, respectively, by HPLC radiochromatogram. Specific uptake of [68Ga]NODAGA-UBI fragments was observed in S.aureus cells. Greater than 64 % of the injected dose was cleared via the renal route at 1 h post injection, and no significant uptake in vital organs of mice was observed with both the agents.

Conclusion

This is the first report on Ga-68 labeled NODAGA-UBI fragments for infection imaging and the agents hold tremendous prospect in PET imaging.
  相似文献   
98.
We report a very rare case of Meckel’s diverticulum with benign stricture presenting as recurrent small bowel obstruction in a malnourished young adult female. Extensive preoperative investigations were unable to diagnose the cause of recurrent obstruction. Segmental small bowel resection with attached diverticulum was performed.  相似文献   
99.
This study examined screen media time usage (SMTU) and its association with personal and socioeconomic factors, as well as the effect of season and type of day, in a Spanish sample of 12-16 year-old school adolescents (N=323). The research design was a cross-sectional survey, in which an interviewer-administered recall questionnaire was used. Statistical analyses included repeated measures analyses of variance, analysis of covariance and structural equation models. Results showed an average of 2.52h per day of total SMTU and partial times of 1.73h per day in TV viewing, 0.27h per day in computer/videogames, and 0.52h per day in mobile use. Four significant predictors of SMTU emerged. Firstly, the type of school was associated with the three media of our study, particularly students from state/public school spent more time on them than their private schools counterparts. Secondly, older adolescents (14-16 years old) were more likely to use computer/videogame and mobile phone than younger adolescents. Thirdly, the more accessibility to household technology the more probable computer/videogames and mobile phone were used. Finally, boys spent significantly more time in mobile phone than girls. Additionally, results revealed that adolescents seemed to consume more TV and computer/videogames in autumn than in winter, and more TV and mobile phones on weekends than on weekdays, especially among state school students. Findings from this study contribute to the existing knowledge on adolescents' SMTU patterns that can be transferred to families and policies.  相似文献   
100.
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