作者： Li, Linsheng;Zeng, Li;Qiu, Changjun;Liu, Linghui

期刊： Journal of X-Ray Science and Technology,2012年20(3):255-267 ISSN：0895-3996

通讯作者： Zeng, L

作者机构： [Li, Linsheng; Zeng, Li; Liu, Linghui] Chongqing Univ, Educ Minist China, Key Lab Optoelect Technol & Syst, ICT Res Ctr, Chongqing 400044, Peoples R China.;[Li, Linsheng; Qiu, Changjun] Univ S China, Coll Mech Engn, Hengyang, Hunan, Peoples R China.;[Zeng, Li] Chongqing Univ, Coll Math & Stat, Chongqing 400044, Peoples R China.

通讯机构： [Zeng, L ] Chongqing Univ, Educ Minist China, Key Lab Optoelect Technol & Syst, ICT Res Ctr, Chongqing 400044, Peoples R China.;Chongqing Univ, Educ Minist China, Key Lab Optoelect Technol & Syst, ICT Res Ctr, Chongqing 400044, Peoples R China.

关键词： Image segmentation<&wdkj&> intensity inhomogeneity<&wdkj&> computer tomography (CT)<&wdkj&> robust statistics<&wdkj&> region-scalable fitting (RSF)

摘要： Intensity inhomogeneity may cause considerable difficulties in segmentation of CT image. In order to overcome the difficulties caused by intensity inhomogeneity, the region-scalable fitting (RSF) model was put forward. RSF model draws upon intensity information in local regions with a controllable scale. But only using intensity information may lead to slow convergence rate and poor denoise ability. Combining the method of robust statistics, RSF model is improved in this paper. In the improved model, the intensity in RSF model is replaced with local robust statistics which is the weighted combination of inter-quartile range, mean absolute deviation and intensity median in local region. Inter-quartile range and mean absolute deviation in local region are introduced to sharpen object boundaries, and intensity median in local region is introduced to reduce image noise. The contrast experiments between RSF model and the improved model are provided, which demonstrate the fast convergence rate and robustness to noise of the improved model. &copy;2012 - IOS Press and the authors. All rights reserved.

语种： 英文

作者： 李润;刘丹;王玥;代正燕;周容;刘婧;张琚;曾果

期刊： 中华流行病学杂志,2015年36(8):803-806 ISSN：0254-6450

作者机构： [王玥; 代正燕; 李润; Zeng, Guo; 刘丹] Department of Nutrition, Food Safety and Toxicology, West China School of Public Health, Sichuan University, Chengdu 610041, China;[周容] West China Second Hospital, Shichuan University;[刘婧] Chengdu Women's and Children's Central Hospital;[张琚] Sichuan Provincial Maternal and Child Health Hospital;[Zeng, Guo] Email: zgmu2007@126. com

关键词： 体重指数;泌乳时间;孕期增重

摘要： 目的探讨孕前BMI和孕期增重对泌乳时间的影响。方法采用纵向研究方法,于2013年3-9月选取成都市妇幼医疗机构产前门诊751名单胎健康孕妇作为基线调查对象,在其分娩前后各随访一次,最终以473名孕妇作为研究对象,通过问卷调查和病历记录获得其孕前体重、分娩方式、新生儿出生体重、泌乳时间及基本信息,测量身高和分娩前体重,计算孕期增重;控制分娩方式、母亲年龄等混杂因素后,采用多因素有序logistic回归模型分析孕前BMI和孕期增重与泌乳时间的关系。结果调查对象泌乳时间<1、1~、24~、48~和≥72 h的构成比分别占16.3%、37.0%、17.5%、18.6%和10.6%。与孕前体重正常组相比,孕前消瘦和孕前超重或肥胖均是泌乳时间延长的危险因素,OR值(95%CI)分别为2.85(1.91 ~4.27)和3.42(1.69 ~ 6.90)。与孕前体重正常且孕期增重适宜组相比,孕前消瘦且孕期增重适宜和过多均是泌乳时间延长的危险因素,OR值(95%CI)分别为2.34(1.31 ~ 4.18)和3.42(1.67 ~ 7.00);孕前超重或肥胖且孕期增重过多是泌乳时间延长的危险因素,OR值(95%CI)为3.10(1.15 ~ 8.37)。结论孕前BMI是泌乳时间的独立影响因素,孕期增重需联合孕前BMI对泌乳时间产生影响。

语种： 中文

作者： Li Linsheng;Lin Guoxiang*;Li Lihui

期刊： Bio-Medical Materials and Engineering,2016年27(2-3):251-258 ISSN：0959-2989

通讯作者： Lin Guoxiang

作者机构： [Lin Guoxiang; Li Lihui; Li Linsheng] Univ South China, Sch Mech Engn, Hengyang 421001, Hunan, Peoples R China.

通讯机构： [Lin Guoxiang] Univ South China, Sch Mech Engn, Hengyang 421001, Hunan, Peoples R China.

关键词： Magnesiunm alloys;bioactivity;biocompatibility;biological composite material;coating;electrophoretic deposition

摘要： In this paper, magnesium matrix hydroxyapatite composite material was prepared by electrophoretic deposition method. The optimal process parameters of electrophoretic deposition were HA suspension concentration of 0.02 kg/L, aging time of 10 days and voltage of 60 V. Animal experiment and SBF immersion experiment were used to test the biocompatibility and bioactivity of this material respectively. The SD rats were divided into control group and implant group. The implant surrounding tissue was taken to do tissue biopsy, HE dyed and organizational analysis after a certain amount of time in the SD rat body. The biological composite material was soaked in SBF solution under homeothermic condition. After 40 days, the bioactivity of the biological composite material was evaluated by testing the growth ability of apatite on composite material. The experiment results showed that magnesium matrix hydroxyapatite biological composite material was successfully prepared by electrophoretic deposition method. Tissue hyperplasia, connective tissue and new blood vessels appeared in the implant surrounding soft tissue. No infiltration of inflammatory cells of lymphocytes and megakaryocytes around the implant was found. After soaked in SBF solution, a layer bone-like apatite was found on the surface of magnesium matrix hydroxyapatite biological composite material. The magnesium matrix hydroxyapatite biological composite material could promot calcium deposition and induce bone-like apatite formation with no cytotoxicity and good biocompatibility and bioactivity. &copy;2016 IOS Press and the authors.

语种： 英文

作者： 粟俊杰;陈海辉;张阳德

期刊： 中国医疗器械杂志,2008年32(6):443-445,448 ISSN：1671-7104

通讯作者： Su, J.J.

作者机构： 南华大学机械工程学院,湖南,衡阳,421001;中南大学卫生部肝胆肠研究中心,湖南,长沙,410008;共创实业集团工程技术中心,湖南,衡阳,421001;[粟俊杰] 南华大学;[陈海辉; 张阳德] 中南大学

关键词： 高频直流电压;牙科X线机;组合式球管;低辐射

摘要： 应用IGBT实现高频逆变,实时采样、脉宽调制确保对阳极高压和管电流的闭环控制,采用微电脑精确控制,组合式球管技术,研制出5台牙科X线机,该机实现了外部无高压,加在X发射管上的电压波动在1%以内,曝光时间误差在3%以内,拍摄的照片可以清晰显示出牙髓腔及周围组织,完全可满足临床透视要求。

语种： 中文