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   1586篇
  免费   77篇
  国内免费   19篇
耳鼻咽喉   8篇
儿科学   62篇
妇产科学   25篇
基础医学   168篇
口腔科学   116篇
临床医学   116篇
内科学   325篇
皮肤病学   27篇
神经病学   46篇
特种医学   165篇
外科学   214篇
综合类   33篇
预防医学   67篇
眼科学   30篇
药学   83篇
  1篇
中国医学   49篇
肿瘤学   147篇
  2023年   12篇
  2022年   15篇
  2021年   43篇
  2020年   28篇
  2019年   44篇
  2018年   43篇
  2017年   22篇
  2016年   26篇
  2015年   48篇
  2014年   62篇
  2013年   75篇
  2012年   92篇
  2011年   74篇
  2010年   67篇
  2009年   69篇
  2008年   80篇
  2007年   69篇
  2006年   56篇
  2005年   47篇
  2004年   46篇
  2003年   46篇
  2002年   42篇
  2001年   32篇
  2000年   25篇
  1999年   25篇
  1998年   29篇
  1997年   31篇
  1996年   42篇
  1995年   38篇
  1994年   38篇
  1993年   21篇
  1992年   26篇
  1991年   25篇
  1990年   20篇
  1989年   31篇
  1988年   31篇
  1987年   22篇
  1986年   20篇
  1985年   18篇
  1984年   16篇
  1983年   14篇
  1982年   11篇
  1981年   8篇
  1980年   9篇
  1978年   6篇
  1977年   9篇
  1976年   6篇
  1975年   4篇
  1973年   3篇
  1969年   4篇
排序方式: 共有1682条查询结果,搜索用时 46 毫秒
1.
Abstract: This study examined physical and financial arrangements for medical care of institutionalised elderly people in Singapore. Chief administrators of all long-term care facilities were interviewed on the existing arrangements for medical care of their residents. Results showed that 66 out of a total of 68 (97%) homes arranged medical care for residents. Of those, 29 homes offered on-site medical care with alternative arrangements when the in-house facilities were not operating. While government-owned homes would pay for all medical costs incurred by their residents, over 48% of voluntary homes and 87% of commercial homes required residents to be financially responsible for their care. The availability of financial support given to residents for payment of medical care was found to be associated with the type of sponsorship of the homes. While there was adequate physical access to medical care, the lack of financial support would pose a potential barrier to use of medical care for institutionalised elderly people.  相似文献   
2.
The relationship between primary tumor proliferative activity and clinical and pathologic characteristics was analyzed in relation to menopausal status in 32 patients with malignant or benign breast disease. The thymidine labeling index (TLI) showed significantly higher median values in the cancer patients (3.48 per cent) than in the patients with benign diseases (1.02 per cent). TLI was not significantly affected by delayed incubation at room temperature for about 1 hour. In the breast cancer patients, TLI did not significantly correlate to tumor size, the presence of axillary lymph node metastasis or pathologic nuclear grading. The only significant difference was limited to the breast cancer patients without axillary lymph node metastasis in relation to menopausal status; the TLI in the premenopausal patients (5.10 per cent) was significantly higher (p<0.05) than that in the postmenopausal patients (2.28 per cent). These data thus suggest that among premenopausal patients without axillary lymph node metastasis, those with a high TLI could be potential candidates for adjuvant chemotherapy.  相似文献   
3.
Prevention has been recognized as a cost-effective method for the control of oral diseases. Knowledge of prevention can influence preventive dental behavior. This study surveyed knowledge on the prevention of dental caries and gum disease among a selected group of adults. Respondents were asked to indicate the importance of numerous preventive measures for prevention of both categories of oral diseases. Results showed that while respondents appropriately identified the importance of regular brushing for prevention, the role of flossing is underestimated. Similarly, there was a lack of appreciation for the value of various fluoride treatment modalities in preventing dental caries. A lack of understanding of dental sealants was also evident. It is concluded that public knowledge on prevention of dental caries and gum disease deviates greatly from current scientific information.  相似文献   
4.
5.
1. In the rabbit jejunum nerveside causes alternating contractions of the longitudinal and circular muscles, which are similar to the peristaltic reflex produced by distension of the gut. These effects are abolished by dibucaine (Nupercaine) and tetrodotoxin. The site of action is located in Auerbach's plexus.

2. Circular muscle contractions due to nerveside are blocked by hexamethonium, nicotine, morphine, atropine and hyoscine. There is no circular response to nerveside after removal of Auerbach's plexus. It is suggested that nerveside acts by stimulating presynaptic nerve terminals which are cholinergic and that the circular muscle is innervated by cholinergic nerve fibres.

3. Longitudinal muscle contractions due to nerveside are not affected by hexamethonium but can be blocked by paralysis of myenteric ganglia with nicotine. They are not abolished by morphine or by cholinolytic drugs. It is suggested that nerveside acts by stimulating either receptors insensitive to acetylcholine in ganglion cells or non-cholinergic presynaptic nerve terminals. It is further suggested that the longitudinal muscle of the rabbit gut is supplied by non-cholinergic as well as cholinergic nerve fibres.

  相似文献   
6.
Sphenochoanal polyp is a rare form of choanal polyp. If unrecognised, they can be mistaken for an antrochoanal polyp. This will result in unnecessary exploration of the maxillary sinus, and a failure to remove the sphenoidal component of the sphenochoanal polyp. Adequate preoperative evaluation with computed tomography or magnetic resonance is mandatory to ascertain the correct diagnosis, and to facilitate the planning of the appropriate surgical procedure. We present two patients with sphenochoanal polyp and a review of the literature.  相似文献   
7.
PURPOSE: We investigate the causes of nocturnal urinary frequency and reasons for its increase with age. MATERIALS AND METHODS: All voided volumes and times were recorded for 3 days in 188 healthy older men without prostatic diseases during a mass screening program for prostatic diseases in Japan. Nocturnal urinary frequency for each night was defined as the frequency during sleep not counting the morning void. Relationships between nocturnal urinary frequency and functional bladder capacity, nocturnal bladder capacity, nocturnal urinary volume and sleep time were analyzed. Age related changes in functional and nocturnal bladder capacity, and nocturnal and diurnal urinary volume were evaluated. RESULTS: Multiple regression analysis demonstrated nocturnal bladder capacity and urinary volume to be significant independent determinants of nocturnal frequency. In age related analysis nocturnal bladder capacity and diurnal urinary volume decreased with age, while nocturnal urinary volume did not change. CONCLUSIONS: Nocturnal urinary volume and nocturnal bladder capacity were the significant determinants of nocturnal urinary frequency in healthy older men. The increase of nocturnal frequency with age was thought to be due to a decrease in nocturnal bladder capacity, since urinary volume did not change. In older men a decrease in water intake might influence age related changes in urinary volume.  相似文献   
8.
9.
Joslyn  JN; Mirvis  SE; Markowitz  B 《Radiology》1988,166(3):817-821
During a 20-month period, fractures of the clivus occurring after craniocerebral trauma were diagnosed with computed tomography (CT) in 11 patients. Five patients had longitudinally oriented fractures; these were fatal in four patients due to either vertebral-basilar artery occlusion, brain stem trauma, or both. Six other patients had transversely oriented fractures that extended through the carotid canal and petrous temporal bone. While less frequently contributing directly to mortality, transverse fractures were also associated with cerebrospinal fluid leaks (two patients) and a cavernous sinus-carotid fistula (one patient). They were not as frequently associated with Horner syndrome or cranial nerve deficits as suggested in the current literature. This retrospective evaluation reveals two distinct injury patterns that demonstrate a difference in related morbidity and mortality.  相似文献   
10.
Rubesin  SE; Kennedy  M; Levine  MS; Rosato  EF; Laufer  I 《Radiology》1988,167(2):345-347
Eccentric ballooning of the distal esophagus was observed radiographically in 11 of 23 patients (48%) who underwent Heller myotomy for achalasia. While, to the authors' knowledge, ballooning at the site of myotomy incision has not been described previously in the radiologic literature, it should be recognized as a normal and frequent postoperative finding. Radiologists should be aware of this finding so that it is not mistaken for postoperative abnormalities following esophagomyotomy or an epiphrenic diverticulum.  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