基于CT影像的人体心脏三维重构

三维重构是研究心脏血流机理及特性等问题的有效手段,本文基于CT断层扫描数据,利用Mimics处理工具对心脏进行三维重构,并对左心室优化模型进行偏差分析,优化改变了重构模型的粗糙度,对左心室结构的影响较小为后续探究心脏内部血流模式及特性、血液生理学参数异变和组织结构病变提供了基础研究。     

An Evaluation of Breastfeeding Promotion Through Peer Counseling in Mississippi WIC Clinics

Objective: This study evaluates the effectiveness of a peer counseling program at increasing breastfeeding by participants in the Mississippi Special Supplemental Nutrition Program for Women, Infants and Children (WIC). Methods: Data from the 1989–1993 Pediatric Nutrition Surveillance System were analyzed to compare breastfeeding rates in clinics with and without peer counseling programs. A questionnaire completed by program staff to describe the program in greater detail helped identify characteristics associated with greater success. Results: The incidence of breastfeeding rose from 12.3% to 19.9% in those clinics with peer counseling programs, but only from 9.2% to 10.7% in clinics without a program. Clinics that started a program earlier showed greater changes in breastfeeding incidence. However, the presence of lactation specialists or consultants in the clinic appeared to be more important than the presence of less-trained peer counselors. Peer counselors who spent more than 45 minutes per participant were more effective than those spending less time. Conclusions: The peer counseling program significantly increased the incidence of breastfeeding, particularly in clinics with lactation specialists and consultants. Success can be enhanced by ensuring that peer counselors spend a great deal of time with the participants.     

Repeated Independent Exposures to Domoic Acid Do Not Enhance Symptomatic Toxicity in Outbred or Seizure-Sensitive Inbred Mice

Domoic acid (DA) is an environmental neurotoxin to humans. Thiswork examines whether repeated exposure to subsymptomatic orsymptomatic nonlethal doses of domoic acid leads to enhancedsymptomatic toxicity in ICR outbred and DBA inbred strains oflaboratory mice. A multiple independent exposure paradigm wasdesigned in which doses were administered intraperito neallyevery other day for 7 days to achieve four separate exposuresto domoic acid. We first examined the effect of repeated exposureon serum clearance of domoic acid. Serum domoic acid levelsdid not differ following a single or repeated exposure. We nextexamined the effect of repeated exposure on symptomatic toxicity.The mean toxicity scores did not show a significant differencebetween single and repeated exposures of either subsymptomatic(0.5 mg/ kg) or symptomatic sublethal (2.0 mg/kg) doses of domoicacid. We then examined the effects of repeated domoic acid exposureon a second strain of mouse. DBA mice were chosen based upontheir sensitivity to kainic acid-induced seizures; however,the ICR mice were more sensitive to low-dose domoic acid toxicity,particularly in terms of onset and duration of stereotypic scratchingbehavior. Our results indicate that both strains of mice havecomparable concentration-dependent toxic responses to domoicacid; however, differences exist in the magnitude of the responseand in specific symptoms. The mean toxicity scores did not showa significant difference when a single exposure (1.0 and 2.0mg/kg domoic acid) and repeated exposure of the same dose werecom pared in the DBA mice. This study provides no evidence thatshort-term repeated exposure to domoic acid in laboratory micealters domoic acid clearance from the serum, or leads to a moresensitive or a greater neurotoxic response.     

Education review: Crossing borders--delivering health information management education across state lines

Since its inception in 1992, the associate degree program in health information management (HIM) of the University of Alaska Southeast has been distance delivered across the state; it was the first distance degree program to be approved by the university's Board of Regents. In the spring of 1995, the HIM program was selected to be part of a pilot brokering project of the Western Interstate Consortium on Higher Education, in which member institutions would offer programs to or receive programs from other member institutions. The university's HIM program was selected by New Mexico and Wyoming, and classes for two groups of Wyoming students were initiated in the fall of 1995. The article summarizes the results of the project for the HIM program and future plans. It also provides an overview of some of the challenges facing institutions with out-of-state or multistate program delivery.     

ST-1 抗兔心缺血复灌作用药效学研究

 目的证实双萜类化合物ST-1抗兔心缺血/复灌损伤作用。方法麻醉下结扎兔冠状动脉左前降支30 min后，再连续灌注60 min，造成心肌缺血再灌注损伤模型。动态观察血流动力学指标：LVSP，LVDP'±dp/dt max，T-dp/dt max，左室发展压(left ventricular developmental pressure,LVDP'),LVEDP,HR,MAP,SAP,DAP。实验分伪手术组、溶剂对照组和ST-1高、中、低3个剂量给药组和氨氯地平阳性药对照组。结果在整个缺血复灌期，ST-1组±dp/dt max，LVSP，LVDP'，T-dp/dt max的变化值明显小于溶剂对照组(P＜0.05)；HR，SAP，DAP和MAP变化值与溶剂对照组之间无显著性差别(P＞0.05)。结论ST-1预处理可明显改善兔心缺血/复灌引起的左室舒缩功能的损伤。同时无扩血管作用，对血压和心率无明显影响。     

辛伐他汀对肺成纤维细胞凋亡的影响

目的研究羟甲基戊二酸单酰辅酶—A(HMG-CoA)还原酶抑制剂辛伐他汀对肺成纤维细胞凋亡的影响。方法以胎儿肺组织为材料，胰蛋白酶消化法培养肺成纤维细胞，免疫组化方法鉴定，以辛伐他汀5μM、10μM、20μM及不含辛伐他汀的溶剂作用72小时，另以辛伐他汀10μM作用24、48、72、96小时，TUNEL，及流式细胞仪定性及定量检测细胞凋亡。结果(1)成功培养出肺成纤维细胞，光镜下细胞成梭形，免疫组化显示细胞表达纤维粘连蛋白和波动蛋白，不表达角化蛋白和结合蛋白。(2）TUNEL检测结果证实辛伐他汀可诱导细胞凋亡，光镜下也显示凋亡细胞的形态改变。流式细胞仪检测结果显示细胞凋亡率随辛伐他汀浓度及作用时间的增加而增加。结论辛伐他汀能以时间和剂量依赖式诱导肺成纤维细胞凋亡。     

mGM-CSF重组质粒的构建、表达及活性鉴定

目的 构建pc—mGM—CSF重组质粒载体，为mGM—CSF基因治疗肿瘤的研究奠定基础。方法 采用RT—PCR方法从小鼠脾脏中获得目的基因mGM—CSF，克隆于pcDNA3.1／Myc-His(-)(A)质粒上，成为pc-mGM-CSF，用PCR、酶切进行鉴定，然后用脂质体转染小鼠骨髓瘤细胞SP2／0，用G418筛选后通过RT—PCR和SDS—PAGE鉴定，将转染SP2／0上清加入NFS-60细胞，检测蛋白活性。结果 重组质粒中含有mGM—CSF基因，在SP2／0中有表达，且表达产物能分泌到肿瘤细胞外，分泌到细胞外的产物用mGM—CSF依赖株NFS-60细胞检测证明具有生物学活性。结论 成功构建含mGM—CSF真核表达重组质粒，有助于进一步研究其抗肿瘤作用。     

UV—微O3法去除饮用水中CCl4的研究

研究了以紫外－微臭氧为主体的光化学激发氧化技术的最佳运行参数，用该工艺处理饮用水中微量有机优先污染物。研究结果表明：紫外－微臭氧工艺对ＣＣｌ４－水中常见有机优先污染物有令人满意的去除效果，经２小时处理后，去除率可达９０％，紫外－微臭氧工艺对饮用水的深度处理能力接近于紫外－臭氧工艺，设备方便，投资少，是一种很有前途的饮用水净化工艺。