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   442篇
  免费   36篇
  国内免费   3篇
耳鼻咽喉   5篇
儿科学   15篇
妇产科学   8篇
基础医学   69篇
口腔科学   16篇
临床医学   60篇
内科学   82篇
皮肤病学   9篇
神经病学   32篇
特种医学   20篇
外科学   47篇
综合类   3篇
预防医学   43篇
眼科学   9篇
药学   26篇
中国医学   3篇
肿瘤学   34篇
  2023年   4篇
  2022年   7篇
  2021年   18篇
  2020年   4篇
  2019年   11篇
  2018年   21篇
  2017年   20篇
  2016年   19篇
  2015年   13篇
  2014年   19篇
  2013年   29篇
  2012年   28篇
  2011年   30篇
  2010年   18篇
  2009年   21篇
  2008年   23篇
  2007年   21篇
  2006年   23篇
  2005年   19篇
  2004年   19篇
  2003年   14篇
  2002年   19篇
  2001年   8篇
  2000年   7篇
  1999年   9篇
  1998年   7篇
  1997年   5篇
  1996年   4篇
  1995年   3篇
  1994年   2篇
  1993年   2篇
  1992年   3篇
  1991年   2篇
  1990年   2篇
  1989年   3篇
  1988年   6篇
  1987年   2篇
  1986年   1篇
  1985年   2篇
  1984年   2篇
  1983年   1篇
  1982年   1篇
  1978年   2篇
  1977年   1篇
  1971年   1篇
  1970年   1篇
  1967年   1篇
  1959年   1篇
  1929年   1篇
  1921年   1篇
排序方式: 共有481条查询结果,搜索用时 31 毫秒
1.
Midazolam is a recently developed water-soluble benzodiazepine that shares anxiolytic, muscle relaxant, hypnotic and anticonvulsant actions with other members of this class. There are limited studies that midazolam can be used successfully to treat seizures in adults and children. In this study, 0.2 mg/kg intramuscular (IM) midazolam was administered to 11 children (eight boys and three girls), aged 3 days to 4 years (mean age 1.8±1.4 years), with seizures of various types. In all but one child, seizures stopped in 15 s–5 min after injection. No side effects were observed. These results suggest that IM administration of midazolam may be useful in a variety of seizures during childhood, especially in case of intravenous (IV) line problem.  相似文献   
2.
3.
4.
OBJECTIVE: The purpose of this study was to compare the diagnostic efficacy of low- and high-field-strength MR imagers in the diagnosis of anterior cruciate ligament tears and meniscus tears. SUBJECTS AND METHODS: In 219 patients with suspected internal derangement of the knee, MR imaging at 0.2 and 1.5 T was performed with similar sequences. Only patients with surgically confirmed diagnosis (n = 90) were included in the statistical analysis. Radiologists were unaware of diagnosis and field strength. Sensitivity, specificity, diagnostic accuracy, and inter- and intraobserver variability were determined. RESULTS: There was excellent correlation between the field strengths in accuracy, sensitivity, and specificity for anterior cruciate ligament and meniscus tears. Accuracy for medial meniscus, lateral meniscus, and anterior cruciate ligament tears was 91-93%, 88-90%, and 93-96%, respectively, at 0.2 T and 91-94%, 91-93%, and 97-98%, respectively, at 1.5 T. Inter- and intraobserver variability values showed excellent correlation (kappa > 0.8). CONCLUSION: The level of diagnostic accuracy in anterior cruciate ligament tears and meniscus tears is comparable for low- and high-field-strength MR imagers.  相似文献   
5.
6.
Different probes are used in dermato-cosmetic research to measure the electrical properties of the skin. The principle governing the choice of the geometry and material of the measuring probe is not well defined in the literature and some device's measuring principles are not accessible for the scientific community. The purpose of this work was to develop a simple inexpensive conductance meter for the objective in vivo evaluation of skin hydration.The conductance meter probe was designed using the basic equation governing wave propagation along Transverse Electromagnetic transmission lines. It consisted of two concentric copper circular electrodes printed on FR4 dielectric material.The performance of the probe was validated by evaluating its measurement depth, its ability to monitor in vitro water sorption–desorption and in vivo skin hydration effect in comparison to that of the Corneometer CM 825. The measurement depth of the probe, 15 μm, was comparable to that of CM 825. The in vitro readings of the probe correlated strongly with the amount of water adsorbed on filter paper. Skin hydration after application of a moisturizer was monitored effectively by the new probe with good correlation to the results of CM 825.In conclusion, a simple probe for evaluating skin hydration was made from off-the-shelf materials and its performance was validated in comparison to a commercially available probe.  相似文献   
7.
8.
9.

Objectives

The aim of this study was to evaluate the strength of the bond between newly introduced self-adhesive resin cements and tooth structures (i.e., enamel and dentin).

Methods

Three self-adhesive cements (SmartCem2, RelyX Unicem, seT SDI) were tested. Cylindrical-shaped cement specimens (diameter, 3 mm; height, 3 mm) were bonded to enamel and dentin. Test specimens were incubated at 37 °C for 24 h. The shear bond strength (SBS) was tested in a Zwick Roll testing machine. Results were analyzed by one-way ANOVA and t-test. Statistically significant differences were defined at the α = 0.05 level. Bond failures were categorized as adhesive, cohesive, or mixed.

Results

The SBS values ranged from 3.76 to 6.81 MPa for cements bonded to enamel and from 4.48 to 5.94 MPa for cements bonded to dentin (p > 0.05 between surfaces). There were no statistically significant differences between the SBS values to enamel versus dentin for any given cement type. All cements exhibited adhesive failure at the resin/tooth interface.

Conclusions

Regardless of their clinical simplicity, the self-adhesive resin cements examined in this study exhibit limited bond performance to tooth structures; therefore, these cements must be used with caution.  相似文献   
10.
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