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   182225篇
  免费   2430篇
  国内免费   100篇
耳鼻咽喉   1640篇
儿科学   7240篇
妇产科学   3462篇
基础医学   18303篇
口腔科学   3120篇
临床医学   13459篇
内科学   32918篇
皮肤病学   1663篇
神经病学   16601篇
特种医学   8322篇
外科学   29356篇
综合类   2256篇
一般理论   16篇
预防医学   17158篇
眼科学   3270篇
药学   10422篇
中国医学   682篇
肿瘤学   14867篇
  2024年   211篇
  2023年   461篇
  2022年   556篇
  2021年   1124篇
  2020年   675篇
  2019年   948篇
  2018年   18709篇
  2017年   14749篇
  2016年   16477篇
  2015年   1856篇
  2014年   1993篇
  2013年   2715篇
  2012年   8553篇
  2011年   20158篇
  2010年   16547篇
  2009年   10127篇
  2008年   18206篇
  2007年   20074篇
  2006年   3271篇
  2005年   4499篇
  2004年   5346篇
  2003年   5928篇
  2002年   4170篇
  2001年   1009篇
  2000年   1265篇
  1999年   716篇
  1998年   426篇
  1997年   372篇
  1996年   258篇
  1995年   246篇
  1994年   226篇
  1993年   176篇
  1992年   155篇
  1991年   171篇
  1990年   218篇
  1989年   182篇
  1988年   143篇
  1987年   117篇
  1986年   100篇
  1985年   123篇
  1984年   94篇
  1983年   95篇
  1982年   100篇
  1981年   69篇
  1980年   103篇
  1979年   59篇
  1978年   66篇
  1977年   71篇
  1976年   63篇
  1974年   62篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
The current study is an example of drug–disease interaction modeling where a drug induces a condition which can affect the pharmacodynamics of other concomitantly taken drugs. The electrophysiological effects of hypokaliemia and heart rate changes induced by the antiasthmatic drugs were simulated with the use of the cardiac safety simulator. Biophysically detailed model of the human cardiac physiology—ten Tusscher ventricular cardiomyocyte cell model—was employed to generate pseudo-ECG signals and QTc intervals for 44 patients from four clinical studies. Simulated and observed mean QTc values with standard deviation (SD) for each reported study point were compared and differences were analyzed with Student’s t test (α?=?0.05). The simulated results reflected the QTc interval changes measured in patients, as well as their clinically observed interindividual variability. The QTc interval changes were highly correlated with the change in plasma potassium both in clinical studies and in the simulations (Pearson’s correlation coefficient?>?0.55). The results suggest that the modeling and simulation approach could provide valuable quantitative insight into the cardiological effect of the potassium and heart rate changes caused by electrophysiologically inactive, non-cardiological drugs. This allows to simulate and predict the joint effect of several risk factors for QT prolongation, e.g., drug-dependent QT prolongation due to the ion channels inhibition and the current patient physiological conditions.  相似文献   
92.
The anti-epileptic drugs phenobarbital and valproic acid have an extremely strong negative effect on cognitive processes such as learning and memory in the developing brain. We examined whether or not curcumin has protective effects on neuronal injury caused by these drugs in the developing rat brain. Young male Wistar rats were studied in two groups, a 7 days old and a 14 days old group (35 rats in each). Both groups were then divided into 7 sub-groups as the control, curcumin, dimethylsulfoxide, phenobarbital, valproic acid, phenobarbital + curcumin, and valproic acid + curcumin groups (n = 5 in each group). At 24 h after the intraperitoneal injection of the compounds, the rats were sacrificed, and the hippocampal tissue was subjected to stereological analysis with the optical fractionation method. Total numbers of neurons in the hippocampus of the 7 days old and 14 days old rats were calculated. It was found that treatment with phenobarbital resulted in a loss of 43% of the neurons, and valproic acid induced a loss of 57% of the neurons in the 7 days old rats. Curcumin prevented this loss significantly with only 19% in the phenobarbital group and 41% in the valproic acid group. In the 14 days old rat groups, phenobarbital was found to reduce the number of neurons by 30%, and valproic acid reduced it by 38%. Curcumin treatment limited neuronal loss to 3% in the phenobarbital + curcumin group and 10% in the valproic acid + curcumin group. These data strongly indicate that curcumin is a protective agent and prevents hippocampal neuronal damage induced by phenobarbital and valproic acid treatment.  相似文献   
93.
94.
95.
96.
97.
98.
Background Spending on biological agents has risen dramatically due to the high cost of the drugs and the increased prevalence of spondyloarthritis. Objective To evaluate the annual cost per patient and cost for each biological drug for treating patients with spondyloarthritis from 2009 to 2016, and to calculate factors that affect treatment cost, such as optimizing therapies by monitoring drug serum levels, the use of biosimilar-TNF inhibitors, and official discounts or negotiated rebates in biologicals acquired by the pharmacy department. Method Retrospective, observational study in a Spanish tertiary hospital. Main outcome Annual cost per patient and per drug. Factors that influenced the costs and socio-demographic parameters and disease activity. Results A total of 129, 215, and 224 patients were treated in 2009, 2013, and 2016, respectively. The annual cost per patient decreased: EUR11,604 in 2009, EUR8513 in 2013, and EUR7464 in 2016. The introduction of new drugs drives economic competition, leading to total savings per drug, with discounts reaching 5.8, 12.4, 16.7, 17.7, 13.7, and 24.8% for original infliximab, etanercept, adalimumab, ertolizumab, golimumab, and secukinumab, respectively, while rebates for biosimilar infliximab reached 31.90% in 2016. The number of patients with optimized therapies reached 47.5% in 2016, which led to cost savings of EUR798,614, in addition to savings from official discounts and rebates of EUR252,706 and savings from optimized therapies of EUR545,908 in 2016. Conclusion The cost of biological treatments declined after official discounts, negotiated rebates, and optimized therapies, leading to a significant decrease in the annual cost per patient. The greatest contribution to economic savings in biological therapy according to our study was biological therapy optimization.  相似文献   
99.
100.
Background Cisplatin-induced nephrotoxicity still occurs despite the intensive hydration approach adapted to prevent its occurrence. Objective Evaluation of the effect of acetazolamide (ACTZ) on minimizing cisplatin-induced nephrotoxicity compared to mannitol when added to hydration regimen. Setting Nasser Institute Cancer Center (NICC), Cairo, Egypt. Method A total of 35 patients planned to receive cisplatin were divided into two groups: 20 patients received mannitol and 15 patients received ACTZ. Both groups received standard hydration measures as well for prevention of cisplatin-induced nephrotoxicity. Main outcome measure Patients’ kidney function was assessed using serum creatinine, creatinine clearance and blood urea nitrogen. Kidney injury was assessed using RIFLE criteria. Patients’ liver function tests and hematological parameters were also monitored. Results Patients in the mannitol group showed higher risk of developing kidney injury (30%) whereas those in the ACTZ group showed lower risk (8.9%), relative risk (RR) 0.269, 95% CI 0.108–0.815. No statistically significant difference occurred between the two groups concerning liver function tests or hematological parameters. Conclusion Use of ACTZ in addition to intensive hydration may have more beneficial effect on minimizing cisplatin-induced nephrotoxicity compared to mannitol plus intensive hydration approach. A large multicenter randomized clinical trials is recommended to confirm study results and to assess effect of ACTZ on tumor response.  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