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   2740篇
  免费   203篇
  国内免费   11篇
耳鼻咽喉   21篇
儿科学   101篇
妇产科学   112篇
基础医学   413篇
口腔科学   88篇
临床医学   346篇
内科学   551篇
皮肤病学   124篇
神经病学   153篇
特种医学   42篇
外科学   188篇
综合类   52篇
一般理论   4篇
预防医学   225篇
眼科学   71篇
药学   223篇
中国医学   50篇
肿瘤学   190篇
  2024年   8篇
  2023年   53篇
  2022年   169篇
  2021年   223篇
  2020年   165篇
  2019年   190篇
  2018年   189篇
  2017年   107篇
  2016年   141篇
  2015年   115篇
  2014年   158篇
  2013年   189篇
  2012年   246篇
  2011年   233篇
  2010年   115篇
  2009年   81篇
  2008年   113篇
  2007年   103篇
  2006年   88篇
  2005年   90篇
  2004年   59篇
  2003年   31篇
  2002年   30篇
  2001年   4篇
  2000年   1篇
  1999年   6篇
  1998年   2篇
  1997年   3篇
  1996年   2篇
  1995年   2篇
  1994年   3篇
  1993年   2篇
  1991年   1篇
  1990年   1篇
  1988年   5篇
  1987年   7篇
  1986年   2篇
  1985年   5篇
  1984年   2篇
  1980年   1篇
  1979年   4篇
  1977年   1篇
  1976年   1篇
  1973年   2篇
  1936年   1篇
排序方式: 共有2954条查询结果,搜索用时 0 毫秒
61.
Lasers in Medical Science - The combination of multiple therapeutic and diagnostic functions is fast becoming a key feature in the area of clinical oncology. The advent of nanotechnology promises...  相似文献   
62.
63.
International Urology and Nephrology - Free radicals play an important role in the different complex course of carcinogenesis. Higher concentrations of reactive oxygen species are highly associated...  相似文献   
64.
65.

Purpose

The aim of this study was to evaluate the effectiveness of oral n-acetyl cysteine, as a potential nephroprotective agent, in preventing and/or attenuating amphotericin B-induced electrolytes imbalances.

Methods

During a one year period, patients were to receive conventional amphotericin b for any indication for at least one week and were randomly allocated to receive either placebo or 600 mg oral n-acetyl cysteine twice daily during the treatment course of amphotericin b. Demographic and clinical data of the study population were gathered. Different aspects of amphotericin b nephrotoxicity including decrease of glomerular filtration rate, hypokalemia, hypomagnesemia, renal magnesium and potassium wasting were assessed. Each patient was monitored for any adverse reaction to n-acetyl cysteine. Sixteen and 14 patients in the n-acetyl cysteine and placebo groups completed the study, 3incidences of hypokalemia (75 % versus 70 %; P?=?0.724) and hypomagnesemia (30 % versus 20 %; P?=?0.468) did not differ significantly between placebo and NAC groups, respectively. Although the rate of AmB nephrotoxicity was higher in the placebo than in the NAC group (60 % versus 40 %), this difference was not statistically significant (P?=?0.209) even after adjusting for probable associated factors of amphotericin b nephrotoxicity (P?=?0.206). The incidence as well as time of onset of electrolyte abnormalities also did not differ significantly between placebo and n-acetyl cysteine groups. About 44 % of n-acetyl cysteine recipients experienced new onset nausea and a mild unpleasant taste during the study.

Conclusion

Oral n-acetyl cysteine during the amphotericin B treatment course was not significantly effective in preventing or mitigating different features of its nephrotoxicity including decrease of glomerular filtration rate, hypokalemia, hypomagnesemia, and renal potassium as well as magnesium wasting.  相似文献   
66.
67.
68.
Annals of Nuclear Medicine - When using perfusion only modified PIOPED II criteria for PE detection, generated non-diagnostic scans are found to be the main diagnostic restriction. The objective of...  相似文献   
69.
70.
Prediction of the diameter of a nanofiber is very difficult, owing to complexity of the interactions of the parameters which have an impact on the diameter and the fact that there is no comprehensive method to predict the diameter of a nanofiber. Therefore, the aim of this study was to compare the multi-layer perceptron (MLP), radial basis function (RBF), and support vector machine (SVM) models to develop mathematical models for the diameter prediction of poly(ε-caprolactone) (PCL)/gelatin (Gt) nanofibers. Four parameters, namely, the weight ratio, applied voltage, injection rate, and distance, were considered as input data. Then, a prediction of the diameter for the nanofiber model (PDNFM) was developed using data mining techniques such as MLP, RBFNN, and SVM. The PDNFMMLP is introduced as the most accurate model to predict the diameter of PCL/Gt nanofibers on the basis of costs and time-saving. According to the results of the sensitivity analysis, the value of the PCL/Gt weight ratio is the most significant input which influences PDNFMMLP in PCL/Gt electrospinning. Therefore, the PDNFM model, using a decision support system (DSS) tool can easily predict the diameter of PCL/Gt nanofibers prior to electrospinning.

A new tool for prediction the diameter of nanofibers is presented: the use of adaptive modeling techniques to predict fiber diameter and study the impact of electrospinning process parameters on electrospinning fiber diameter.  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