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   153篇
  免费   12篇
  国内免费   3篇
儿科学   1篇
妇产科学   5篇
基础医学   6篇
临床医学   1篇
内科学   3篇
皮肤病学   1篇
特种医学   1篇
外科学   2篇
综合类   11篇
预防医学   59篇
眼科学   43篇
药学   13篇
中国医学   18篇
肿瘤学   4篇
  2023年   4篇
  2021年   6篇
  2020年   3篇
  2019年   3篇
  2018年   3篇
  2017年   5篇
  2016年   6篇
  2015年   8篇
  2014年   9篇
  2013年   22篇
  2012年   11篇
  2011年   9篇
  2010年   14篇
  2009年   4篇
  2008年   9篇
  2007年   12篇
  2006年   8篇
  2005年   10篇
  2004年   3篇
  2003年   5篇
  2002年   4篇
  1999年   1篇
  1998年   2篇
  1996年   2篇
  1994年   1篇
  1993年   1篇
  1991年   1篇
  1989年   1篇
  1980年   1篇
排序方式: 共有168条查询结果,搜索用时 31 毫秒
1.
Background: “Poppers” is a slang term for a group of alkyl nitrites that are used as recreational drugs. Their inhalative intoxication leads to muscle relaxation, analgesia, and euphoria. Maculopathy is a rare but serious side-effect. Patients/Methods: Clinical, imaging, and electrophysiological findings of seven patients with maculopathy after consumption of poppers were presented. Results: All seven patients were male with a median age of 35 years (range 28–45 years), the median duration of periodical poppers use until the onset of symptoms was 9.8 years (one day to 25 years). Five of seven patients were HIV-positive, one patient was negative, and the HIV-status of one patient was unknown. Median average of visual acuity at presentation was 20/30 in each eye. In all patients, optical coherence tomography (OCT) showed pathognomonic alterations of the outer foveal retina. One patient showed an almost complete restitution of the maculopathy six months after cessation of drug use and following the oral intake of Lutein. Imaging alterations returned to normal and visual acuity recovered from 20/50 and 20/30 (right and left eye, respectively) to 20/20 on both eyes. Follow up of two other cases showed no relevant functional decline or improvement. Discussion: Toxic maculopathy due to the consumption of poppers is an important differential diagnosis in acute visual loss without clinico-morphological correlate. Optical coherence tomography is the only reliable diagnostic tool in these cases. Complete recovery of visual function and macular morphology is rare, even after cessation of drug abuse. Oral lutein therapy may have a beneficial effect.  相似文献   
2.
Macular telangiectasia type 2 also known as idiopathic perifoveal telangiectasia and juxtafoveolar retinal telangiectasis type 2A is an acquired bilateral neurodegenerative macular disease that manifests itself during the fifth or sixth decades of life. It is characterized by minimal dilatation of the parafoveal capillaries with graying of the retinal area involved, a lack of lipid exudation, right-angled retinal venules, refractile deposits in the superficial retina, hyperplasia of the retinal pigment epithelium, foveal atrophy, and subretinal neovascularization (SRNV). Our understanding of the disease has paralleled advances in multimodality imaging of the fundus. Optical coherence tomography (OCT) images typically demonstrate the presence of intraretinal hyporeflective spaces that are usually not related to retinal thickening or fluorescein leakage. The typical fluorescein angiographic (FA) finding is a deep intraretinal hyperfluorescent staining in the temporal parafoveal area. With time, the staining may involve the whole parafoveal area but does not extend to the center of the fovea. Long-term prognosis for central vision is poor, because of the development of SRNV or macular atrophy. Its pathogenesis remains unclear but multimodality imaging with FA, spectral domain OCT, adaptive optics, confocal blue reflectance and short wave fundus autofluorescence implicate Müller cells and macular pigment. Currently, there is no known treatment for this condition.  相似文献   
3.
AIM: To detect whether the combination of vincamine, thioctic acid and lutein will improve the retina and optic nerve functions in cases of an opaque media with an optic nerve and/or a retinal defect or not. METHODS: Totally 2000 patients (2000 eyes) of corneal opacities with defects in the optic nerve or/and the retinal functions were studied. Every patient received three types of drugs: thioctic acid with cyanocobalamine, vincamine, and lutein. The drugs were given daily for 3-12mo according to patient’s responses. Full field flash electroretinogram (ERG) and flash visual evoked potential (VEP) were done before treatment and at 1, 3, 6, and 12mo sequentially. Patients were followed up for 12mo. RESULTS: In the 2000 eyes, 1000 eyes had both moderate optic nerve and retinal function defects; and 840 eyes out of the 1000 improved with the medical treatment. Another 500 eyes out of the 2000 eyes had extinguished retinal function with normal optic nerve function and only 125 eyes of them improved. The 290 out of the 2000 eyes had severe defects in optic nerve with normal retinal function and 130 of them improved. Another 210 eyes have mild optic nerve and retinal function defects and 194 improved. CONCLUSION: The combination of vincamine, thioctic acid with cyanocobalamine, and lutein improved both retina and optic nerve functions mainly in mild and moderate defect than in severe cases.  相似文献   
4.
 目的利用耗散动力学方法(DPD)模拟叶黄素分子在变性淀粉中分布。方法利用MaterialsStudio4.0软件中自带的Visualizer模块,构建叶黄素与变性淀粉3D模型。利用Discover和AmorphousCell两个模块计算溶解度参数。利用模块模拟微囊中叶黄素分布状态。结果该模拟结果显示了变性淀粉包合叶黄素分子的聚集形态和各珠子运动能力。利用模拟结果,通过实验确定了变性淀粉与叶黄素投料比例为100∶40,利用喷雾干燥法制备叶黄素微囊。微囊产率为47.63%,微囊效率为85.79%。用电镜扫描(SEM)考察了微囊的结构,粒径约为70μm。结论耗散动力学仿真模拟可以很好的呈现微囊中药物的分布状态以及预测投料比例。  相似文献   
5.
叶黄素热稳定性及热降解动力学研究   总被引:1,自引:0,他引:1  
夏祎稚  邵卫樑 《安徽医药》2012,16(7):890-893
目的考察叶黄素的热稳定性并估算其不同温度下保存时间、降解反应级数及其动力学数据。方法利用紫外分光光度法考察叶黄素含量与紫外吸收值的线性关系,并以此测定叶黄素在不同温度下热降解数据。用积分法及Arrhenius公式估算其降解反应级数和反应动力学数据以及保存时间。结果叶黄素含量与紫外吸收值呈很好的线性关系;其热降解反应为1.5级较为合适。结论其热降解反应活化能为77.16 kJ.mol-1,指前因子K0=5.66E+10h-1。在摄氏4℃下保存时间t1/2为241 d。  相似文献   
6.
目的:观察叶黄素(LU)对顺铂(CP)损伤大鼠肝组织超微结构的影响。方法:将24只雌性SD大鼠随机分为生理盐水组(NS组),化疗模型组(CP组),和LU干预组(LU+CP组)。NS组及CP组大鼠灌胃玉米油,LU+CP组大鼠按40mg/kg 灌胃LU玉米油溶液。灌胃7d后,CP组和LU+CP组腹腔注射CP 5mg/kg,NS组腹腔注射等量生理盐水。注射4d后,剖取肝脏,在光镜、透射电镜下观察大鼠肝组织形态结构改变。结果:应用LU可减轻CP所致的肝细胞质空泡化,肝门管区纤维化等改变,同时可减轻CP引起的线粒体嵴结构断裂或消失、内质网呈片层状,及染色质边集于核膜下等超微结构改变。结论:预防性喂饲LU可对CP损伤大鼠肝脏病理及超微结构可产生一定的保护作用。  相似文献   
7.
Carotenoid absorbability from arugula (Eruca sativa) was estimated from the contents of the triacylglycerol-rich lipoproteins (TRL) of 15 women over a 6 h time interval, yielding an average apparent absorption of 0.27 μmole of β-carotene (5.6 μmole intake), whereas a similar intake of standard β-carotene resulted in the absorption of 0.59 μmole. The corresponding rates for the raw and cooked leaves were 18.2 ± 7 and 22.9 ± 13nmole·L?1h?1 (P < 0.05), against 37.1 ± 12nmole·L?1h?1 for β-carotene capsules. For lutein, the apparent mean uptakes were 5.6 ± 4 and 6.7 ± 4nmole·L?1h?1, for the raw and cooked, respectively. It was concluded that the relative loading of β-carotene onto TRLs is favored over that of lutein and that absorbability of these arugula carotenoids by normal adults is substantial.  相似文献   
8.
In the United States, dietary reference intakes describe the relations between nutrient intakes and indicators of adequacy, prevention of disease, and avoidance of excessive intakes among healthy populations for essential nutrients but not dietary bioactive components (DBCs), whose absence from the diet is presumably not deleterious to health (i.e., does not cause a deficiency syndrome). An appropriate framework is needed for establishing recommended intakes for which public health messages and food labeling for DBCs can be derived, because their putative health benefits may not be readily defined in the context of nutritional essentiality. In addition, a myriad of factors make determining their intake and status and investigating their discrete contributions to health particularly challenging. Therefore, the ASN Dietary Bioactive Components Research Interest Section felt it worthwhile to convene a special “hot topic” session at the 2014 Experimental Biology meeting to discuss this issue and serve as a call for future scientific dialogue on establishing a framework for recommended intakes of DBCs. This session summary captures the discussions and presentations that transpired during this session.  相似文献   
9.
目的:观察万寿菊叶黄素的长期毒性,为其安全应用提供参考。方法:将大鼠随机分为5组,空白对照组,溶媒对照组,叶黄素高剂量组[57.0 mg·(kg·d)-1]、中剂量组[23.5 mg·(kg·d)-1]、低剂量组[5.7 mg·(kg·d)-1],连续给药26周,停药4周,观察大鼠的一般行为、体质量增长、食量消耗、血液学及血液生化学指征、尿常规检查、系统尸解及组织病理学诊断。结果:长期毒性实验中,与同期溶媒对照组比较,叶黄素高剂量组、中剂量组、低剂量组动物行为活动、进食量等检查均未见异常;血液学指标、血液生化指标和尿液指标未发现与供试品有关的异常改变,病理组织学检查未发现与叶黄素相关的异常改变。结论:在本实验条件下,未观察到万寿菊叶黄素明显毒性反应,应用较安全。  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