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   1582篇
  免费   90篇
  国内免费   41篇
耳鼻咽喉   3篇
儿科学   42篇
妇产科学   22篇
基础医学   147篇
口腔科学   71篇
临床医学   116篇
内科学   152篇
皮肤病学   18篇
神经病学   114篇
特种医学   32篇
外科学   104篇
综合类   122篇
预防医学   170篇
眼科学   6篇
药学   464篇
中国医学   95篇
肿瘤学   35篇
  2023年   7篇
  2022年   23篇
  2021年   43篇
  2020年   34篇
  2019年   32篇
  2018年   33篇
  2017年   35篇
  2016年   42篇
  2015年   55篇
  2014年   69篇
  2013年   120篇
  2012年   64篇
  2011年   89篇
  2010年   58篇
  2009年   52篇
  2008年   55篇
  2007年   46篇
  2006年   52篇
  2005年   43篇
  2004年   37篇
  2003年   30篇
  2002年   32篇
  2001年   24篇
  2000年   18篇
  1999年   21篇
  1998年   31篇
  1997年   23篇
  1996年   19篇
  1995年   25篇
  1994年   27篇
  1993年   17篇
  1992年   18篇
  1991年   22篇
  1990年   27篇
  1989年   21篇
  1988年   21篇
  1987年   20篇
  1986年   28篇
  1985年   33篇
  1984年   22篇
  1983年   31篇
  1982年   37篇
  1981年   29篇
  1980年   29篇
  1979年   28篇
  1978年   25篇
  1977年   16篇
  1976年   19篇
  1975年   14篇
  1974年   5篇
排序方式: 共有1713条查询结果,搜索用时 328 毫秒
51.
目的:考察不同稀释浓度的痰热清注射液对儿童急性上呼吸道感染(children with acute upper respiratory tract infection,AURTI)的疗效与安全性。方法:抽取2018年1月—12月间收治的采用痰热清注射液治疗的AURTI患儿108例资料,按照痰热清注射液的稀释浓度不同将其分为高浓度组29例、中浓度组40例和低浓度组39例;分析不同痰热清注射液的稀释浓度对各组患儿的临床症状复常时间、总有效率和用药期间不良反应发生率差异。结果:高、中浓度组患儿用药后症状和体征的恢复时间相当(<5 d),但早于低浓度组(<7 d);高、中浓度组用药后的总有效率分别为89.66%和87.50%,经两组间比较其差异无统计学意义(P>0.05),但均显著高于低浓度组(64.10%);中、低浓度组患儿治疗期间不良反应发生率分别为7.50%和5.13%,经两组间比较其差异无统计学意义(P>0.05),但均显著低于高浓度组(31.03%)。结论:痰热清注射液不同稀释浓度对治疗AURTI患儿的疗效和安全性影响较大;适当稀释痰热清注射液的浓度不仅具有良好的临床疗效,而且安全性较高。  相似文献   
52.
We evaluated antimicrobial susceptibility pattern of 42 Salmonella isolates from February 2012 through January 2013. We also determined the minimum inhibitory concentrations (MICs) of azithromycin against Salmonella isolates and compared them with corresponding disc diffusion sizes. Entire 42 isolates were sensitive to chloramphenicol, 41 (97.6%) were sensitive to cotrimoxazole and amoxicillin each. MICs for azithromycin ranged from 2 μg/ml to 24 μg/ml, corresponding zone diameters ranged from 15 mm to 33 mm and the two were significantly correlated (P = 0.001). Our results indicate that whereas, azithromycin is a potential therapeutic option, the sensitivity to the first line drugs and absence of multidrug resistance reinforce the concept of antimicrobial recycling.  相似文献   
53.
目的探讨先天性卵巢发育不全综合征(Turnersyndrome,TS)患儿自发的青春发育与染色体核型及性激素水平之间的关系。方法30例Turner综合征患儿进行染色体检查,评估第二性征及性腺发育情况,检测性激素水平。结果染色体核型分4组,第1组45,XO,10例;第2组嵌合型,9例;第3组x染色体结构畸变,10例;第4组伴有Y染色体,1例。30例患儿随访至15周岁,其中10例出现不同程度的自发性青春发育,20例呈无性发育,4组患儿中以嵌合型TS出现自发青春发育几率最大。有青春发育患儿的性激素水平与无性发育患儿的性激素水平有显著差异。结论Turner综合征患儿自发性青春发育与染色体核型及性激素水平有密切相关性。  相似文献   
54.
55.
We report on two pregnant women who either had de novo restless legs syndrome (RLS) or had marked enhancement of preexisting RLS symptoms during pregnancy. Both patients had ferritin values <50 μg/L at baseline. The patients had relevant sleep disorders and daytime symptoms caused by RLS. The women were treated in an open paradigm with intravenous iron sucrose. A few weeks after therapy, both patients experienced a significant reduction or even remission of RLS symptoms. Their quality of life and sleep substantially improved and no treatment-related adverse effects were observed. According to our initial experience, intravenous iron sucrose administration appears to be an effective therapy in RLS patients with low ferritin values during pregnancy.  相似文献   
56.
The purpose was to study differences in the caries increment rate as influenced by various sugars. The trial involved almost complete substitution of sucrose (S) by fructose (F) or xylitol (X) during a period of 2 years. There were no significant initial differences as to caries status between the prospective sugar groups; 35 subjects in the S-group, 38 in the F-group, and 52 in the X-group. During the entire study 10 subjects discontinued or were excluded. The clinical and radiographical observer error was reported and discussed. After 2 years the mean increment of decayed, missed and tilled tooth surfaces was 7.2 in the S-group, 3.8 in the F-group, and 0.0 in the X-group. The weakness of the DMFS-index in not showing the development of new secondary caries and the increase in size of the lesions was overcome by expressing the caries activity in terms of indices showing the total quantitative and qualitative development. The results showed a massive reduction of the caries increment in relation to xylitol consumption. Fructose was found to be less cariogenic than sucrose. It was suggested that the non- and anticariogenic properties of xylitol principally depend on its lack of suitability for microbial metabolism and physico-chemical effects in plaque and saliva.  相似文献   
57.
58.
Bisphenol A (BPA) is a widespread environmental endocrine disrupting chemical. Although many animals and in vitro studies reported that BPA may affect female fertility through the effect on maturing oocytes and meiotic cell division, but the data from human studies are limited and inconclusive. The study was conducted to examine the association between urinary BPA concentration and in vitro reproductive outcomes (metaphase II (MII) oocyte yield, top quality embryo, fertilization rate, implantation rate and clinical pregnancy) among women from an infertility clinic.The study participants were enrolled in the Infertility Center in Poland. 450 women aged 24-44 (n = 674 IVF cycles) provided urine samples. The urinary concentrations of BPA were evaluated using validated gas chromatography ion-tap mass spectrometry method. Clinical outcomes of IVF treatment were abstracted from patients electronic chart records. To assess the relationship between urinary BPA concentrations early examined reproductive outcomes generalized linear mixed models were used.The detection rate of BPA in urine samples was 98% and the geometric mean 1.59 ± 2.15 ng/ml. A significant decrease was observed between urinary concentration of BPA and implantation (p = 0.04) and decreased MII oocyte count (p = 0.03). There was no association between other examined IVF outcomes: embryo quality, fertilization rate and clinical pregnancy and BPA exposure.Exposure to BPA may have a negative effect during the early stages of human development. The studies among the larger and more diverse population are needed to confirm the results.  相似文献   
59.
60.
Ocular hypertension due to increased intraocular pressure is a major risk factor for the development of glaucoma. Rapid clearance and low ocular bioavailability are drawbacks of conventional ocular treatments. This requires frequent and long-term application of antiglaucoma drugs which in turn cause local side effects and are a major cause of therapeutic failure due to loss of persistence in using glaucoma therapy. In this study, a semisynthetic, biocompatible, oxidized sucrose crosslinker was developed and used in the formulation of chitosan-gelatin hydrogel for the sustained release of timolol to control ocular hypertension. The swelling properties of the hydrogel showed a strong relationship with the oxidized sucrose concentration. Mucoadhesive properties of the hydrogel were studied and the in vitro release profiles demonstrated that crosslinking with oxidized sucrose reduced the release rate of the entrapped timolol. The results of both in vitro and in vivo studies supported that the formulated hydrogel maintained the release and in turn the efficacy of timolol for a longer period of time compared to the conventional eye drops. This is expected to reduce the frequency of drug application onto the eye surface and in turn enhances patients’ convenience. In conclusion, the developed formulation represents a promising platform for an effective and compliant treatment of ocular hypertension.  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