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   1099篇
  免费   82篇
  国内免费   4篇
耳鼻咽喉   38篇
儿科学   23篇
妇产科学   45篇
基础医学   227篇
口腔科学   16篇
临床医学   159篇
内科学   144篇
皮肤病学   10篇
神经病学   79篇
特种医学   21篇
外科学   81篇
综合类   9篇
预防医学   118篇
眼科学   9篇
药学   150篇
肿瘤学   56篇
  2023年   6篇
  2022年   3篇
  2021年   18篇
  2020年   16篇
  2019年   19篇
  2018年   22篇
  2017年   28篇
  2016年   25篇
  2015年   23篇
  2014年   50篇
  2013年   56篇
  2012年   75篇
  2011年   77篇
  2010年   44篇
  2009年   34篇
  2008年   69篇
  2007年   77篇
  2006年   62篇
  2005年   71篇
  2004年   47篇
  2003年   55篇
  2002年   59篇
  2001年   14篇
  2000年   9篇
  1999年   14篇
  1998年   20篇
  1997年   14篇
  1996年   16篇
  1995年   5篇
  1994年   17篇
  1993年   13篇
  1992年   12篇
  1991年   8篇
  1990年   10篇
  1989年   9篇
  1988年   15篇
  1987年   7篇
  1986年   12篇
  1985年   5篇
  1984年   5篇
  1983年   7篇
  1982年   6篇
  1981年   5篇
  1980年   3篇
  1979年   2篇
  1977年   4篇
  1972年   6篇
  1944年   1篇
  1943年   1篇
  1929年   1篇
排序方式: 共有1185条查询结果,搜索用时 375 毫秒
1.
2.
1. The effects of graded treadmill exercise on renal blood flow (RBF) were examined in seven rabbits, in which congestive heart failure (CHF) was produced by the administration of doxorubicin, 1 mg/kg, twice weekly for 8 weeks, and in seven controls. A third group of five rabbits underwent doxorubicin treatment with the addition of surgical section of the left renal sympathetic nerve. 2. During submaximal exercise, there was a small reduction in RBF in controls, which was greatly exaggerated in CHF. 3. In both control and heart failure rabbits, there was a precipitous fall in RBF as exercise fatigue developed. 4. Renal sympathectomy ablated these changes in RBF during exercise. 5. It is concluded that in heart failure there is an exaggerated, sympathetically mediated, diversion of blood flow away from the kidney. The onset of exercise fatigue in both normal and heart failure rabbits is accompanied by a marked intensification of this process.  相似文献   
3.
4.
5.
6.
A case with a fatal outcome caused by infection with Fusobacterium species was seen in a patient recently operated on for heavy snoring with uvulo-palato-pharyngoplasty (UPPP). The mechanism of infection is discussed. It is concluded that a febrile episode seen in patients less than 2 weeks postoperatively should be considered a serious symptom and be treated intensively after thorough examination. © 1994 John Wiley & Sons, Inc.  相似文献   
7.
Autologous periosteal transplantation (without chondrocyte cell transplantation) for treating traumatic articular cartilage defects of the patella gives pain relief in uncontrolled clinical studies. To study the whole transplanted area macroscopically and microscopically, animal studies are motivated. In this pilot study, we reproduce the surgical technique for periosteum transplantation on human patella to a rabbit model. A full-thickness cartilage defect of the whole patella was created in eight adult female rabbits. The defect was treated with autologous periosteal transplantation. After surgery, the rabbits were allowed free activity. This is the difference compared to the treatment in humans, where our group uses CPM for 5 days and non-weight-bearing for 12 weeks. After 21 weeks, there was a diffuse synovitis in all transplanted knees, and in five of eight knees there were signs of osteoarthritis in the patello-femoral joint. Histologically, in three animals, small islands of hyaline cartilage surrounded by fibrocartilage were seen in the transplanted area. In the other five animals, fibrocartilage was the predominant tissue. In contrast to previous experimental studies using a rabbit model, we did not achieve hyaline cartilage resurfacing.  相似文献   
8.
BACKGROUND: The occurrence of small vessel arteriosclerosis in the myocardium, kidney, and lung in dogs with naturally occurring myxomatous mitral valve disease has not been previously investigated systematically. METHODS: Twenty-one dogs with naturally occurring congestive heart failure and 21 age-matched, sex-matched, and weight-matched control dogs underwent extensive pathological and histopathological examination. Morphometry and scoring of tissue sections were used to measure arterial narrowing and fibrosis in the myocardium, kidney, and lung; and intimal thickness and plaque formation in the aorta and pulmonary artery. RESULTS: Dogs with congestive heart failure had significantly more arterial narrowing in the left ventricle (P < .003), lung (P < .0001), and kidney (P < .02); intimal-medial thickening in the pulmonary artery (P = .04); and fibrosis in the left ventricle (P < .0001) than control dogs. However, they did not have more plaque formation or intimal-medial thickening in the aorta than controls. There was significantly more arterial narrowing in papillary muscles than in all other locations in dogs with congestive heart failure (P < .002). In control dogs, arterial changes were less pronounced and did not differ in different locations. CONCLUSIONS: Dogs with naturally occurring myxomatous mitral valve disease have significantly more arterial changes in the myocardium, lung, and kidney, and significantly more fibrosis in the myocardium than control dogs. This could have important implications in the management of myxomatous mitral valve disease and raises interesting questions about the occurrence and importance of intramural small vessel disease in humans with primary mitral valve prolapse.  相似文献   
9.
Subunit intranasal vaccines offer the prospect of inducing combined systemic-mucosal immunity against mucosally transmitted infections such as human immunodeficiency virus. However, although human studies have demonstrated the induction of active immunity, secretory immunoglobulin A (sIgA) responses are variable, and no study has demonstrated protection by accepted vaccine-licensing criteria as measured by direct toxin-neutralizing activity. Using the genetically inactivated mutant diphtheria toxoid CRM(197) in a bioadhesive polycationic polysaccharide chitosan delivery system, we found that a single nasal immunization was well tolerated and boosted antitoxin neutralizing activity in healthy volunteers, which could be further boosted by a second immunization. The neutralizing activity far exceeded accepted protective levels and was equivalent to that induced by standard intramuscular vaccine and significantly greater than intranasal immunization with CRM(197) in the absence of chitosan. A striking but unexpected observation was that although unilateral intranasal immunization induced circulating antitoxin antibody-secreting cells, a nasal antitoxin sIgA response was seen only after the second immunization and only in the vaccinated nostril. If these data are reproduced in larger studies, an intranasal diphtheria vaccine based on CRM(197)-chitosan could be rapidly licensed for human use. However, a restricted sIgA response suggests that care must be taken in the priming-boosting strategy and clinical sampling techniques when evaluating such vaccines for the induction of local mucosal immunity.  相似文献   
10.

Introduction

MED13L-related intellectual disability is characterized by moderate intellectual disability (ID), speech impairment, and dysmorphic facial features. We present 8 patients with MED13L-related intellectual disability and review the literature for phenotypical and genetic aspects of previously described patients.

Materials and methods

In the search for genetic aberrations in individuals with ID, two of the patients were identified by chromosomal microarray analysis, and five by exome sequencing. One of the individuals, suspected of MED13L-related intellectual disability, based on clinical features, was identified by Sanger sequencing.

Results

All 8 individuals had de novo MED13L aberrations, including two intragenic microdeletions, two frameshift, three nonsense variants, and one missense variant. Phenotypically, they all had intellectual disability, speech and motor delay, and features of the mouth (open mouth appearance, macroglossia, and/or macrostomia). Two individuals were diagnosed with autism, and one had autistic features. One had complex congenital heart defect, and one had persistent foramen ovale. The literature was reviewed with respect to clinical and dysmorphic features, and genetic aberrations.

Conclusions

Even if most clinical features of MED13L-related intellectual disability are rather non-specific, the syndrome may be suspected in some individuals based on the association of developmental delay, speech impairment, bulbous nasal tip, and macroglossia, macrostomia, or open mouth appearance.  相似文献   
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