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   985篇
  免费   60篇
  国内免费   18篇
耳鼻咽喉   4篇
儿科学   49篇
妇产科学   6篇
基础医学   117篇
口腔科学   22篇
临床医学   138篇
内科学   158篇
皮肤病学   25篇
神经病学   35篇
特种医学   210篇
外科学   82篇
综合类   39篇
预防医学   49篇
眼科学   2篇
药学   80篇
中国医学   1篇
肿瘤学   46篇
  2022年   4篇
  2021年   8篇
  2020年   9篇
  2019年   4篇
  2018年   8篇
  2017年   6篇
  2016年   9篇
  2015年   13篇
  2014年   25篇
  2013年   27篇
  2012年   16篇
  2011年   24篇
  2010年   27篇
  2009年   23篇
  2008年   28篇
  2007年   36篇
  2006年   31篇
  2005年   33篇
  2004年   19篇
  2003年   21篇
  2002年   17篇
  2001年   22篇
  2000年   15篇
  1999年   40篇
  1998年   42篇
  1997年   55篇
  1996年   40篇
  1995年   42篇
  1994年   24篇
  1993年   28篇
  1992年   23篇
  1991年   32篇
  1990年   23篇
  1989年   22篇
  1988年   33篇
  1987年   28篇
  1986年   23篇
  1985年   21篇
  1984年   12篇
  1983年   9篇
  1982年   21篇
  1981年   13篇
  1980年   23篇
  1979年   6篇
  1978年   14篇
  1977年   23篇
  1976年   13篇
  1975年   8篇
  1972年   4篇
  1968年   4篇
排序方式: 共有1063条查询结果,搜索用时 31 毫秒
1.
2.
3.
Bottomley  PA; Lee  Y; Weiss  RG 《Radiology》1997,204(2):403
  相似文献   
4.
In a single-centre prospective trial 200 consecutive patients undergoing thoracic surgery were randomised to receive one of two prophylactic regimes against deep vein thrombosis (DVT). These were 5000 units of subcutaneous heparin twice a day, alone or combined with the wearing of graded compression stockings. The diagnosis of DVT was made clinically and with 131I labelled fibrinogen. Six DVTs developed in the stocking group and 11 in the non-stocking group. The results suggest that the use of stockings reduces the incidence of DVT when added to herparin but the difference is not statistically significant. To obtain a predictive index for the development of DVT, discriminant analysis was applied to the control and stocking groups separately and combined. Five simple clinical variables gave a true positive prediction rate, for the combined group, of 94% and a false positive prediction rate of 26%.  相似文献   
5.
Prior studies have shown that pneumothorax is one of the more difficult entities to diagnose with digitized radiography. This study was designed to test whether increasing resolution from 1.25 to 2.5 line pairs per millimeter (lp/mm) and image processing (edge enhancement from unsharp masking) would increase accuracy and confidence in the diagnosis of pneumothorax, as well as normal cases and other forms of lung disease. Conventional radiographs were digitized with use of a laser reader and then reformatted as film hard copy. Eleven observers read 35 cases reformatted in three different ways (1.25 lp/mm, 2.5 lp/mm, 1.25 lp/mm unsharp mask). The images with finer resolution (2.5 lp/mm) and unsharp mask images were superior to those with coarser resolution (1.25 lp/mm) for the diagnosis of pneumothorax. There was no difference in diagnostic accuracy for normal patients. For abnormalities other than pneumothorax, the unsharp mask images were significantly worse. Confidence in the diagnosis of pneumothorax and other abnormalities was highest with the finest resolution (2.5 lp/mm).  相似文献   
6.
Acetazolamide is a weak diuretic used to decrease production of aqueous humor in the eye. Hemodialysis patients undergoing ocular surgery may benefit from acetazolamide; however, no pharmacokinetic data are available for this group of patients. We report a patient who received acetazolamide 250 mg every 6 hours after ophthalmic surgery and developed reversible neurological side effects associated with very high plasma concentrations. Using pharmacokinetic analysis, we suggest an alternate administration of acetazolamide for end-stage renal patients.  相似文献   
7.
8.
卢日刚 《药学学报》1992,27(11):871-874
This paper provides a basic principle and experimental technique of derivative signal multiplier spectrophotometry in multicomponent mixture. A microcomputer was used to process the spectral data measured on a manual spectrophotometer (UV-7520) for the determination of moroxydine hydrochloride in Gan Mao Qing capsules. Quantitative analysis of multicomponent mixture can be done without sample separation. The selection of optimal wavelength pairs is performed through the program with a computer. The method needs no special spectrophotometer and is simple, rapid and easy to operate. The mean recovery was 99.98 +/- 0.53% (n = 12).  相似文献   
9.
In the radiographical evaluation of the orbital apex syndrome, standard radiographs, tomograms, and computed tomographic scans have proved useful in the demonstration of the bony pathology, especially for optic canal fractures. The limitation of these methods, however, remains in their inability to provide accurate delineation of the associated soft tissue pathology, including the presence of optic nerve sheath hematoma. Recent developments in computer technology and graphic imaging are now available to provide an accurate three-dimensional radiographical analysis of the extent of skeletal and soft tissue injury in the orbital apex syndrome. The physician, in essence, can perform a radiographical "living autopsy". The technique was used to evaluate a patient with bilateral apex syndrome. It clearly showed that a severe direct injury to the intracanalicular portion of the optic nerve was responsible for the development of blindness in this patient. The progression of optic nerve injury, from perineural sheath hematoma to the ultimate development of optic nerve atrophy and fibrosis, was radiographically documented.  相似文献   
10.
The application of rigid fixation devices has expanded the craniomaxillofacial surgeon's armamentarium and allows greater versatility of osteotomy design and fixation. Further studies are under investigation to determine the degree of "interference" with growth as a result of application of rigid fixation devices. Our preliminary thought is that bone is dynamic and "liquid" enough to allow the driving forces of the developing cerebral tissue to remodel and recontour the bone tissue into a normal configuration and contour. Problems with relapse and resorption appear greatly reduced for both bone grafts and bone flaps. As the biomaterials industry continues to perfect rigid fixation devices, further advances will be forthcoming.  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