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   2238篇
  免费   121篇
  国内免费   7篇
耳鼻咽喉   13篇
儿科学   131篇
妇产科学   18篇
基础医学   353篇
口腔科学   52篇
临床医学   198篇
内科学   383篇
皮肤病学   39篇
神经病学   144篇
特种医学   104篇
外科学   277篇
综合类   43篇
一般理论   3篇
预防医学   116篇
眼科学   74篇
药学   235篇
中国医学   5篇
肿瘤学   178篇
  2022年   21篇
  2021年   54篇
  2020年   32篇
  2019年   43篇
  2018年   55篇
  2017年   31篇
  2016年   63篇
  2015年   59篇
  2014年   79篇
  2013年   94篇
  2012年   146篇
  2011年   147篇
  2010年   95篇
  2009年   79篇
  2008年   121篇
  2007年   101篇
  2006年   107篇
  2005年   91篇
  2004年   80篇
  2003年   83篇
  2002年   72篇
  2001年   58篇
  2000年   51篇
  1999年   64篇
  1998年   38篇
  1997年   16篇
  1996年   17篇
  1995年   11篇
  1992年   31篇
  1991年   21篇
  1990年   26篇
  1989年   35篇
  1988年   18篇
  1987年   19篇
  1986年   14篇
  1985年   20篇
  1984年   16篇
  1983年   16篇
  1982年   15篇
  1980年   15篇
  1977年   10篇
  1976年   17篇
  1975年   14篇
  1974年   15篇
  1973年   12篇
  1971年   14篇
  1970年   11篇
  1969年   10篇
  1968年   15篇
  1966年   13篇
排序方式: 共有2366条查询结果,搜索用时 0 毫秒
31.
This study uses a policy-capturing approach to examine 816 pay-increase decisions made by 17 hospital administrators. Subjects were asked to respond to packages consisting of hypothetical employees who varied in performance levels, specialized skills or expertise, difficulty in replacing, potential turnover, and current salary. Results indicated that all five factors were significant and in the direction expected for most of the raters. None of the hypothesized interaction effects were significant for any of the raters. Results also showed that subjects' explicit rankings of the importance of the factors did not correspond highly with the rankings of their regression weights. The implications of this study for both research and practice are discussed.  相似文献   
32.
The experiments were conducted to identify the toxin that produces pulmonary oedema in Mesobuthus tamulus (BT) envenomed animals. Crude BT venom was subjected to Sephadex gel filtration (G-75) and the fractions were screened for optical density (OD), neurotoxicity (prolongation of compound action potential in frog sciatic nerve) and lethality. All these parameters exhibited a peak between 54-94 ml eluates. Fractions of this peak were pooled (SP) and loaded on to carboxymethyl cellulose column. The column was then eluted with increasing buffer concentrations at constant pH and temperature. Eluates were screened for neurotoxicity and OD. Four peaks of neurotoxic activity (T1-T4) were detected. T2 and T3 were lethal whereas T1 and T4 were non-lethal. T2 exhibited mainly neurotoxicity and failed to augment phenyldiguanide (PDG)-induced reflex response or to produce pulmonary oedema. T3 was having minimal neurotoxic actions but augmented PDG-reflex and produced pulmonary oedema. The effects of T3 persisted even after dialysis with 8 kDa cut-off filter but not those of T2. The T3 effects resembled toxic manifestations of BT venom and were blocked by aprotinin pre-treatment. T3 demonstrated a band at approximately 100 kDa in SDS-PAGE. The results demonstrate the presence of a lethal, high molecular weight, pulmonary oedema producing toxin in BT venom.  相似文献   
33.
34.
An audit of the selective neonatal BCG immunisation programme showed that only 51% of eligible infants received the vaccination. Infants of Indian subcontinental origin (ISC) were significantly more likely to have been vaccinated than non-ISC infants (ISC 70% v non-ISC 29%). Greater awareness of the eligibility of non-ISC infants for BCG as well as simplification of the eligibility criteria are needed to help increase BCG vaccination rates.  相似文献   
35.
36.
37.
俄罗斯不同气候地区不同功能水体中克雷伯菌属广泛分布。克雷伯菌属可见于遭受生物、化学污染的集中供水的地表水源,无防护的地下蓄水层,缺乏有效清洁、消毒系统的饮用水。研究表明,水体中的克雷伯菌属具有致病性和毒性,对现代药物和消毒剂(氯、紫外线)具有抗性,很容易穿透进入地下蓄水层。克雷伯菌属细菌有很强的致病性(粘附力、侵袭力、磷酸酯酶、卵磷脂酶、脱氧核糖核酸酶、溶血活性),含有致病性遗传标记cnf-1。克雷伯菌属(100 CFU/dm3)可引起急性肠道感染。在不检测总大肠菌群的情况下,检测水体尤其是饮用水中的克雷伯菌属,可以评估所用水的流行病学危险。  相似文献   
38.
Medicare beneficiaries with incomes at or near the poverty level are also eligible for benefits provided by state Medicaid programs. The Medicare Modernization Act of 2003 details special provisions for these "dually eligible" individuals compared with other Medicare beneficiaries. Issues related to enrollment, benefits, and patient compliance are discussed, as well as challenges physicians face in caring for this vulnerable population.  相似文献   
39.
Testicular metastasis presenting as a testicular mass is an extremely rare condition. There are only nine previously reported cases where testicular mass was the first clinical manifestation of underlying malignancy. Here we report a case of metastatic mucin secreting adenocarcinoma in testis presenting as a testicular mass with unknown primary. We have given a brief review of literature about the spread of tumor to testes.  相似文献   
40.
Cannabinoids have been used medicinally for centuries, and in the last decade, attention has focused on their broad therapeutic potential particularly in seizure management. While some cannabinoids have demonstrated anticonvulsant activity in experimental studies, their efficacy for managing clinical seizures has not been fully established. This commentary will touch on our understanding of the brain endocannabinoid system’s regulation of synaptic transmission in both physiological and pathophysiological conditions, and review the findings from both experimental and clinical studies on the effectiveness of cannabinoids to suppress epileptic seizures. At present, there is preliminary evidence that non-psychoactive cannabinoids may be useful as anticonvulsants, but additional clinical trials are needed to fully evaluate the efficacy and safety of these compounds for the treatment of epilepsy.  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