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   3201篇
  免费   234篇
  国内免费   9篇
耳鼻咽喉   41篇
儿科学   111篇
妇产科学   91篇
基础医学   400篇
口腔科学   16篇
临床医学   394篇
内科学   555篇
皮肤病学   44篇
神经病学   378篇
特种医学   74篇
外科学   380篇
综合类   54篇
一般理论   1篇
预防医学   403篇
眼科学   70篇
药学   206篇
  1篇
中国医学   1篇
肿瘤学   224篇
  2024年   5篇
  2023年   43篇
  2022年   90篇
  2021年   152篇
  2020年   88篇
  2019年   149篇
  2018年   165篇
  2017年   134篇
  2016年   108篇
  2015年   114篇
  2014年   141篇
  2013年   200篇
  2012年   284篇
  2011年   322篇
  2010年   169篇
  2009年   98篇
  2008年   201篇
  2007年   173篇
  2006年   129篇
  2005年   144篇
  2004年   112篇
  2003年   84篇
  2002年   74篇
  2001年   15篇
  2000年   28篇
  1999年   16篇
  1998年   11篇
  1997年   15篇
  1996年   12篇
  1995年   7篇
  1994年   6篇
  1993年   5篇
  1992年   8篇
  1991年   6篇
  1990年   8篇
  1989年   7篇
  1988年   8篇
  1987年   6篇
  1986年   13篇
  1985年   8篇
  1983年   5篇
  1982年   5篇
  1981年   4篇
  1979年   14篇
  1978年   9篇
  1974年   4篇
  1973年   6篇
  1972年   4篇
  1969年   3篇
  1967年   4篇
排序方式: 共有3444条查询结果,搜索用时 15 毫秒
21.
By analyzing the arrival times of specimens and reorganizing laboratory instruments to accommodate a higher volume of tests, the author's chemistry department was able to profit from the additional reference testing it was able to handle.  相似文献   
22.
23.
The activity of N-acetyl galactosamine-6-sulfate sulfatase was studied for the first time in the liver and brain of a patient with a clinically typical case of Morquio syndrome with keratosulfaturia. As has been demonstrated in the fibroblasts of patients with this syndrome, this enzymatic activity was markedly decreased in both organs. Neuropathological examination revealed moderately swollen neurons containing PAS-positive, coarse globular inclusions in the cerebral cortex, Ammon's horn, basal ganglia, and thalamic nuclei. Ultrastructurally, the inclusions consisted of stacked, straight or loose, wavy membranes of various lengths, often associated with pale or moderately electron dense homogeneous "lipid droplets." These ultrastructural features of the inclusions were closely similar to the granulomembranous bodies of Hurler syndrome and the inclusions described in type B of the Sanfilippo syndrome. Unlike those mucopolysaccharidoses, however, no abnormalities were found in the gangliosides in the brain of the patient with Morquio syndrome.  相似文献   
24.
BACKGROUND: The polysulfonated napthlyurea suramin has shown significant antitumor activity in patients with hormone-refractory metastatic prostate cancer. The mechanism by which suramin exerts this effect is unknown. In 1993, prostate-specific membrane antigen (PSM) was identified as a prostate biomarker that is elevated in hormone-refractory and metastatic prostate cancer. PSM is a glutamate exocarboxypeptidase capable of cleaving the terminal alpha-linked glutamate from the dipeptide N-acetyl-aspartyl-glutamate (NAAG) and the gamma-linked glutamates from folate polyglutamate. METHODS: Using a NAAG hydrolytic radioenzymatic assay, we tested whether suramin had any effect on the enzymatic activity of PSM. RESULTS: We demonstrate that suramin potently inhibits the enzymatic activity of PSM with a K(i) = 15 nM and 68 nM for the membrane-associated and soluble forms of PSM, respectively. In addition, we show that suramin inhibition of PSM enzyme activity displays the kinetics of a classic competitive inhibitor. CONCLUSIONS: This is one of the most potent activities described for suramin to date and may represent a portion of its pharmacologic and/or toxicological mechanism of action.  相似文献   
25.
26.
BackgroundLow health literacy affects 80–90 million Americans with low-income, minority populations being more vulnerable to this condition. One method of addressing limited literacy that may be particularly well accepted within vulnerable populations is the use of educational board games in order to emphasize seeking health information from reliable sources such as pharmacists.ObjectiveThe research objective was to determine if the use of educational board games could impact community pharmacy patron intentions to seek pharmacist advice in an urban, minority, economically-disadvantaged population.MethodsFour medication-related educational games were played at an urban community pharmacy under the leadership of pharmacy students in the setting of a health party. Game messages, design, and evaluation processes were uniquely guided by community members' input. A verbally administered questionnaire measured game impact via knowledge and perception questions with responses compared between a non-randomly allocated intervention group and a control group.ResultsNinety-nine adults were included in the intervention (or game) group and 94 adults were in the control group. Game participants were significantly more likely than the control group to indicate they would seek pharmacist medication advice in the future.ConclusionEducational board games played in the setting of a health party can be a fun and effective way to convey selected health messages within an urban, minority, economically disadvantaged population. Community input into game development and layering multiple strategies for overcoming health literacy barriers were essential components of this initiative.  相似文献   
27.
BackgroundMany esophageal pathologies are clinically treated by resection and reconstruction of the esophagus. Surgical esophagectomy remains a morbid procedure and despite minimally invasive advances, has changed little in decades. Novel approaches to esophageal segmental resection and reconstruction are an unmet need.MethodsCircumferential thoracic esophageal transection was performed in both male and female pigs and the defects reconstructed using 5 or 10 cm polyurethane (PU) tubular grafts and stented. A subset were treated with stent only. Animals were survived to 14, 30, 60, and 399 days. Tissues were evaluated histologically, and via non-invasive serial endoscopy and contrast swallowing studies in long-term animals.ResultsLuminal patency was achieved in all animals with no clinical evidence of leak. In short-term animals, there was healing noted in all cases with a variably sized region of ulceration remaining at the most central part of the repaired tube (between the proximal and distal anastomosis). In four long-term animals following stent removal, two resumed normal diet and thrived, while two animals were euthanized prior to the proposed endpoint because of stricture formation and inability to tolerate a normal diet. Re-epithelialization was observed in all groups, and more complete over time.ConclusionsThe PU scaffold provides a matrix across which formation of new tissue can occur. The mechanisms through which this happens remain unclear, but likely a combination of fibrosis and tissue contraction, in conjunction with new tissue formation.  相似文献   
28.
29.
The management of congenital heart disease (CHD) remains a significant challenge in developing regions. Since 2006, China California Heart Watch has provided cardiac services in China’s Yunnan province. Our Grants for Kids program aims to diagnose and fund surgical and nonsurgical treatments for underprivileged children with congenitally malformed hearts. This report analyzes our patient outcomes. From 2007 to 2010, 36 children with CHD underwent either surgical or percutaneous procedures at local Chinese medical centers, and 94% of our patients could be contacted for follow-up assessment. The mortality and complication rates of our patient population compare favorably with international data. Our study provides a model through which networking with local hospitals and regional cardiac centers can be an effective way to assist developing areas in providing cardiac care to rural underserved populations.  相似文献   
30.
PURPOSE: To evaluate the feasibility of concurrent weekly Cis-platinum chemoradiation (CRT) in the curative treatment of primary vaginal cancer. METHODS: A retrospective review was performed of all primary vaginal cancer patients treated with curative intent at the Ottawa Hospital Regional Cancer Centre between 1999 and 2004 using concurrent Cis-platinum CRT. RESULTS: Twelve patients were treated with concurrent weekly CRT. The median age at diagnosis was 56 years (range, 34-69 years), and the median follow-up was 50 months (range, 11-75 months). Ten patients (83%) were diagnosed with squamous cell carcinoma and 2 patients (17%) with adenocarcinoma. The distribution according to stage was as follows: 6 (50%) Stage II, 4 (33%) Stage III, and 2 (17%) Stage IVA. All patients received pelvic external beam radiotherapy (EBRT) concurrently with weekly intravenous Cis-platinum chemotherapy (40 mg/m(2)) followed by brachytherapy (BT). The median dose of EBRT was 4500 cGy given in 25 fractions over 5 weeks. Ten patients received interstitial BT, and 2 patients received intracavitary BT, with the median dose being 3000 cGy. The 5-year overall survival, progression-free survival, and locoregional progression-free survival rates were 66%, 75%, and 92%, respectively. Late toxicity requiring surgery occurred in 2 patients (17%). CONCLUSIONS: For the treatment of primary vaginal cancer, it is feasible to deliver concurrent weekly Cis-platinum chemotherapy with high-dose radiation, leading to excellent local control and an acceptable toxicity profile.  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