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   20600篇
  免费   1229篇
  国内免费   60篇
耳鼻咽喉   333篇
儿科学   1118篇
妇产科学   498篇
基础医学   1779篇
口腔科学   358篇
临床医学   1615篇
内科学   4935篇
皮肤病学   329篇
神经病学   1037篇
特种医学   739篇
外科学   3714篇
综合类   452篇
一般理论   3篇
预防医学   1091篇
眼科学   909篇
药学   1551篇
  1篇
中国医学   71篇
肿瘤学   1356篇
  2023年   164篇
  2022年   349篇
  2021年   769篇
  2020年   402篇
  2019年   615篇
  2018年   706篇
  2017年   489篇
  2016年   501篇
  2015年   510篇
  2014年   792篇
  2013年   997篇
  2012年   1501篇
  2011年   1356篇
  2010年   853篇
  2009年   668篇
  2008年   1007篇
  2007年   1022篇
  2006年   957篇
  2005年   889篇
  2004年   795篇
  2003年   674篇
  2002年   603篇
  2001年   481篇
  2000年   510篇
  1999年   403篇
  1998年   161篇
  1997年   138篇
  1996年   117篇
  1995年   118篇
  1994年   105篇
  1993年   83篇
  1992年   279篇
  1991年   250篇
  1990年   219篇
  1989年   211篇
  1988年   172篇
  1987年   176篇
  1986年   155篇
  1985年   168篇
  1984年   147篇
  1983年   141篇
  1982年   65篇
  1981年   75篇
  1979年   116篇
  1978年   86篇
  1977年   63篇
  1974年   75篇
  1973年   110篇
  1972年   100篇
  1971年   68篇
排序方式: 共有10000条查询结果,搜索用时 93 毫秒
91.
92.
Summary A pharmacokinetic study of randomised crossover design was carried out in which eight patients with recurrent stage pTa or pT1 transitional cell carcinoma of the bladder were given thio TEPA (30 mg) in distilled water or in 10% (v/v) Tween 80 (30 ml) intravesically for 2 h, followed 3 months later by the alternative treatment. Thio TEPA and its primary metabolite, TEPA, were measured in plasma and urine using a sensitive and specific chromatographic assay. Large differences between patients were observed in the proportion of thio TEPA absorbed, ranging from 20%–78%. Peak plasma levels of thio TEPA were observed within 1 h of intravesical administration. By 2 h after administration the plasma levels of TEPA were similar to those of thio TEPA and, in contrast to those of the parent compound, remained at a similar level over the next 4 h. The rate of absorption of thio TEPA was not influenced by Tween 80, but it did cause statistically significant increases in mean peak plasma levels (from 101 to 154 ng/ml) and mean AUC values (from 0.376 to 0.496 g h per ml) and a decrease in the mean half-life (from 1.83 to 1.25 h). To obtain plasma levels similar to those achieved after instillation with thio TEPA alone, the dose should be reduced with Tween 80.  相似文献   
93.
The nutritional status of 584 preschool children in an urban slum of Srinagar district was assessed through interviews of mothers conducted in a house-to-house survey, the clinical assessment of child nutritional status, and the anthropometric measurement of the children using accepted standard techniques. The anthropometric measurements of the children were compared to the 50th percentile of the Harvard Standard, while the classification recommended by the Indian Academy of Pediatrics was adopted for the categorization and grading of protein energy malnutrition. 60.45% of the children were malnourished, comprised of 33.22%, 20.89%, and 6.34% of children with grade I, II, and III degrees of malnutrition, respectively. Higher prevalence of malnutrition is associated with higher age, female sex, lower per capita income, higher birth order, and lower parental literacy. Parental literacy status followed by birth order and per capita income were the most important factors associated with preschool child malnutrition.  相似文献   
94.
We investigated the effects of ciprofibrate, a potent peroxisome proliferator, on ethanol metabolism in mice. The blood alcohol levels of mice fed a liquid diet containing both ciprofibrate and ethanol were markedly depressed compared with mice fed the ethanol-containing diet alone. Ciprofibrate markedly induced enoyl-CoA hydratase/3-hydroxyacyl-CoA dehydrogenase, hydrogen peroxide, and to a lesser extent catalase in both control and ethanol-diet fed mice. Northern blot analysis indicated no significant upregulation of cytochrome P450IIE1 mRNA by ciprofibrate. Our study suggests that peroxisome proliferators increase ethanol catabolism through hydrogen peroxide production, thus allowing utilization of the catalase pathway. These findings indicate that catalase has the potential to provide a significant pathway for ethanol metabolism under conditions of peroxisome proliferation.  相似文献   
95.
A carcinoma arising within a fibroadenoma is an unusual occurrence, with only a little over 100 reported cases. The purpose of this report is to increase the awareness of this entity and to discourage the practice of rendering a diagnosis on gross examination of the tumor. We are reporting a case with two distinct primary tumors within the same breast, one of which was arising within the fibroadenoma. Only two such cases have been previously reported.  相似文献   
96.
A case of Ehlers-Danlos Syndrome in a 19 years old male involving cutaneous and skeletal systems is reported. A clinical scoring system to diagnose such cases is highlighted.  相似文献   
97.
In this article we provide a commentary on the various reasonings behind the Law Lords' unanimous judgements in their recent decision (25 June 1998) in Regina v. Bournewood Community and Mental Health NHS Trust, Ex parte L. After summarizing the judgment and commenting on its important implications, we suggest a way forward. The 1995 Law Commission incapacity proposals, on which the 1997 consultation paper Who Decides? was based, do afford a mechanism which could resolve much of the practical difficulty which practitioners feared from the Appeal Court decision, whilst at the same time affording the sorts of rights which the House of Lords decision denies.  相似文献   
98.
BACKGROUND: Oesophagogastrectomy is the best available treatment for patients with carcinoma of the oesophagus or cardia. However, surgical resection may lead to increased mortality, morbidity and longer hospital stays in elderly (aged over 70 years) high risk patients. METHODS: To assess the impact of balanced pre-emptive and postoperative analgesia combined with early mobilisation in elderly patients undergoing oesophagogastrectomy we consecutively studied 52 patients (30 male, 22 female) of 75+/-4.2 years of age (mean+/-SD). Pre-emptive analgesia was by pre-incisional percutaneous paravertebral block combined with an opiate and a nonsteroidal anti-inflammatory drug (NSAID) premedication. Postoperative maintenance analgesia was by NSAID and continuous extrapleural intercostal nerve block. Following surgery all but three patients were returned to the ward. RESULTS: The hospital mortality rate was 7.6%. Morbidity caused by cardiovascular (27%), respiratory (23%) and cerebrovascular (19%) complications occurred in 19 patients, with two patients requiring ventilatory support. The mean hospital stay for the survivors was 10 days (range 8 to 30 days). All the survivors had their swallowing restored to normal and returned to their accustomed environment. CONCLUSIONS: These data suggests that surgical treatment can be achieved in the elderly high risk patients with acceptable mortality and morbidity. This is achieved by early mobilisation enabled by balanced pre-emptive and postoperative analgesia.  相似文献   
99.
100.
Cyclosporine A (CsA) neurotoxicity is an iatrogenic disease with significant morbidity and occasional mortality. We retrospectively reviewed the cases of CsA neurotoxicity among bone marrow transplant recipients at our institution, and summarized the current literature on the subject. The neurologic presentation is varied and the neurologic manifestations are reversible, even after prolonged toxicity, in most instances. Serum CsA level is useful in evaluation, as the level is high in most instances. However, in a case of suspected neurotoxicity, withdrawal of the drug is the only way of determining presence or absence of such toxicity. The electrophysiologic studies, especially electroencephalogram (EEG), is very sensitive in identifying the problem, but lacks specificity. On the other hand, the neuroimaging studies are helpful in making a diagnosis if they show characteristic findings of hyperintense lesions affecting posterior cerebral regions on T2 weighted magnetic resonance images (MRI) or white matter hypodensities on computed tomographic (CT) scan. These lesions are probably due to breakdown of blood-brain barrier resulting in leakage of fluid in interstitial space. The breakdown could be serious enough to cause microhemorrhages that may coalesce to produce macrohemorrhages.  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