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   142篇
  免费   4篇
  国内免费   9篇
儿科学   6篇
妇产科学   4篇
基础医学   14篇
口腔科学   4篇
临床医学   18篇
内科学   23篇
皮肤病学   6篇
特种医学   40篇
外科学   12篇
综合类   13篇
预防医学   6篇
眼科学   1篇
药学   6篇
肿瘤学   2篇
  2022年   2篇
  2021年   2篇
  2019年   3篇
  2018年   1篇
  2016年   2篇
  2015年   1篇
  2014年   3篇
  2013年   5篇
  2012年   4篇
  2011年   6篇
  2010年   7篇
  2009年   4篇
  2008年   2篇
  2007年   4篇
  2006年   2篇
  2005年   6篇
  2004年   4篇
  2003年   5篇
  2002年   4篇
  2001年   3篇
  2000年   3篇
  1999年   1篇
  1998年   7篇
  1997年   13篇
  1996年   9篇
  1995年   8篇
  1994年   6篇
  1993年   3篇
  1992年   4篇
  1991年   3篇
  1990年   2篇
  1989年   1篇
  1988年   2篇
  1987年   1篇
  1985年   3篇
  1984年   1篇
  1983年   1篇
  1982年   1篇
  1980年   1篇
  1979年   1篇
  1977年   5篇
  1976年   3篇
  1975年   2篇
  1972年   1篇
  1970年   1篇
  1944年   1篇
  1943年   1篇
排序方式: 共有155条查询结果,搜索用时 9 毫秒
41.
42.
The development of techniques to efficiently deliver genes using nonviral approaches can broaden the application of gene delivery in medical applications without the safety concerns associated with viral vectors. Here, we designed a clustered integrin-binding platform to enhance the efficiency and targetability of nonviral gene transfer to HeLa cells with low and high densities of αvβ3 integrin receptors. Arg-Gly-Asp (RGD) nanoclusters were formed using gold nanoparticles functionalized with RGD peptides and used to modify the surface of DNA/poly(ethylene imine) (PEI) polyplexes. DNA/PEI polyplexes with attached RGD nanoclusters resulted in either 5.4- or 35-fold increase in gene transfer efficiency over unmodified polyplexes for HeLa cells with low- or high-integrin surface density, respectively. The transfection efficiency obtained with the commercially available vector jetPEI-RGD was used for comparison as a vector without clustered binding. JetPEI-RGD exhibited a 1.2-fold enhancement compared to unmodified jetPEI in cells with high densities of αvβ3 integrin receptors. The data presented here emphasize the importance of the RGD conformational arrangement on the surface of the polyplex to achieve efficient targeting and gene transfer, and provide an approach to introduce clustering to a wide variety of nanoparticles for gene delivery.  相似文献   
43.
SUMMARY The antiseptic and analgesic effectiveness of different preparations of lignocaine gel used prior to flexible cystoscopy were studied in patients recruited over a 12-month period. This random study involved 106 patients in four groups. There appeared to be no difference in bacterial colonisation of the urethra between the groups. Urethral analgesia was improved when higher volumes of gel were used. It was concluded that high-volume gel preparations (>20 ml) with no antiseptic provided optimal conditions for flexible cystoscopy.  相似文献   
44.
45.
46.
47.
SUMMARY: Recent studies have highlighted the intrinsic toxicity of filtered proteins and their contribution to deterioration of renal function. In-depth analysis of proteinuria may assess the degree of glomerular and/or tubular involvement and help in the prognostication of an individual patient. One should consider not only the quantity but also the quality of the urinary protein. Apart from quantitating the total urinary protein, assessment of the quality of the protein may be achieved by performing sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) for an overview assessment follow by automated nephelometry or simple radial immunodiffusion measurement of specific proteins for calculating the selectivity index and detecting tubular dysfunction.  相似文献   
48.
49.
Yang  PC; Luh  KT; Sheu  JC; Kuo  SH; Yang  SP 《Radiology》1985,155(2):451-456
Twenty-five patients, each of whom had peripheral intrathoracic lesions that were smaller than 5.0 X 5.0 cm in size and not diagnosed by conventional methods, underwent real-time sonography and ultrasonically guided aspiration biopsy. The lesions included 18 nodules, two infiltrates, and five cavitary lesions. Sonography showed homogeneous hypoechoic or isoechoic density with well-defined margins in 16 of the nodules, and heterogeneous echogenicity with irregular margins in infiltrates. The cavitary lesions showed a hyperechoic ring with a central sonolucent area. Biopsy specimens were successfully obtained by percutaneous aspiration under ultrasound guidance in 24 (96%) of the patients, and a positive diagnosis was established in 21 (84%) by cytology and/or histology. All 17 malignant lesions were diagnosed by aspiration biopsy, while only four of seven benign lesions were diagnosed by this method. Two patients (8%) experienced minimal pneumothorax after aspiration biopsy. We conclude that real-time sonography, including ultrasonically guided aspiration biopsy, is a useful and safe method for examination of peripheral intrathoracic lesions and has a high diagnostic yield.  相似文献   
50.
Background Chronic renal failure is known to cause various nail pathologies. They may be directly related to the renal condition itself or its complications or to the therapy. Objective To compare nail changes in end‐stage renal failure patients under haemodialysis with healthy persons and to study the potential relationship with various parameters in the patients. Patients and Methods The study comprised 100 patients with chronic renal failure under regular haemodialysis as well as 100 healthy control subjects of matched age and sex. Both groups were subjected to full history taking and thorough general and nail examination. Complete blood picture, liver and kidney function tests and fasting blood glucose level were investigated. Results Nail disorders were more prevalent in patients (76%) than in control group (30%). The half and half nail was the most common finding (20%) followed by – in descending manner – absent lunula, onycholysis, brittle nail, Beau's lines, clubbing, longitudinal ridging, onychomycosis, subungual hyperkeratosis, koilonychias, total leukonychia, splinter hemorrhage, pitting and pincer nail deformity. There was non‐significant correlation between nail changes and age of the patients or duration of haemodialysis. In addition, no evidence of significant relation was found between nail changes and both haemoglobin and albumin levels. Conclusion Frequent nail changes are observed on systematic nail examination of uraemic patients undergoing haemodialysis; however, the cause of them remains obscure and could not be traced to a particular abnormality in the renal condition, medication or the procedure itself and it needs further investigations.  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