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1.
为研究广东省乙型肝炎 (乙肝 )疫苗纳入计划免疫管理 10年后儿童血清乙肝病毒感染标志物 (HBVM )的变化 ,采用分层多阶段随机抽样法 ,将全省分 4层 ,共抽取 12个县 2 4个村的 196 3名儿童为研究样本。采血用固相放射免疫法 (SPRIA)检测乙肝病毒表面抗原 (HBsAg)、乙肝病毒核心抗体 (抗 HBc)、乙肝病毒表面抗体 (抗 HBs)。2 0 0 2年调查 1~ 14岁儿童乙肝疫苗接种率为 78 81% ,全程接种率为 74 17%。其中 1~ 9岁儿童乙肝疫苗全程接种率为 81 73% ,10~ 14岁为 6 0 32 %。 1~ 14岁儿童HBsAg携带率、抗 HBc阳性率、HBV感染率分别从 1992年的 19 86 %、5 3 5 9%、71 4 1%降至 2 0 0 2年的 8 5 6 %、2 2 5 7%、31 33%。其中 1~ 9岁儿童的HBsAg携带率、抗 HBc阳性率、HBV感染率分别从 1992年的 17 88%、4 7 0 9%、6 7 4 4 %下降至 2 0 0 2年的 5 75 %、14 4 9%、2 1 81%。乙肝疫苗接种后 ,1~ 3岁儿童抗 HBs阳性率为 5 2 0 2 %~ 6 2 18%。由于实施了加强免疫 ,4~ 14岁儿童的抗 HBs维持在 5 9 32 %~ 6 5 80 %。广东省乙肝疫苗纳入计划免疫管理 10年后 ,全省 1~ 14岁儿童HBV感染率已大幅度下降 ,抗 HBs阳性率大幅度升高 ,取得了良好的经济和社会效益。  相似文献   
2.
To perform true three-dimensional activation experiments in the human brain, dedicated localized echo-volume imaging (L-EVI) methods were developed. Three-dimensional acquisition allows generation of activation maps with minimal vascular enhancement related to inflow effects. The rapid acquisition of the L-EVI (~100 msec) reduces signal instabilities caused by motion, facilitating the detection of the small intensity changes expected with brain activation. Single-shot L-EVI was performed on normal volunteers at 1.5 T, imaging a three-dimensional predefined volume (240 × 45 × 45 mm3) in the superior portion of the brain with a spatial resolution of 3.75 × 5 × 5 mm3. Increased brain coverage was achieved with a multi-volume imaging (three-shot) version, which simultaneously achieved effective suppression of signals from cerebrospinal fluid. In addition, both asymmetric spin-echo (ASE) and spin-echo (SE) versions of the technique were used to detect blood oxygenation level dependent (BOLD) signal changes in the motor cortex with a finger-tapping paradigm. Images obtained by the L-EVI sequence were qualitatively comparable to standard multislice two-dimensional echo-planar images. Both ASE and SE functional MRI (fMRI) experiments showed consistent activation in the contralateral primary sensorimotor cortex. Furthermore, significant differences in location and magnitude of activation was observed between the two methods, confirming theoretical predictions.  相似文献   
3.
山西省计划免疫冷链设备现状调查   总被引:5,自引:1,他引:4  
为了解山西省计划免疫冷链设备现状,于2001年5月对全省各级卫生防疫站进行了调查.结果显示截止调查时全省装备的6种主要冷链设备共4419台(件,下同),其中前10年(1986~1995年)装备2489台,占56.3%;后6年(1996~2001年)装备1930台,占43.7%.在4419台中,当前正常运转的1930台(43.7%),尚可使用的1057台(23.9%),损坏报废的1432台(32.4%).为满足当前需要,全省尚需增补1888台,其中县、乡两级需增补普通冰箱1011台,低温冰箱805台,疫苗运输车35辆;省、市两级需增补普通冷库4台,低温冷库10台,冷藏车9辆,疫苗运输车14辆.说明需增补的重点在基层.  相似文献   
4.
本文应用有限总体抽样和批质量保证抽样方法对浙江省兰溪市三个乡(镇)的儿童计划免疫“四苗”覆盖率进行了现场调查,结果显示样本率与总体率以及两种抽样方法的样本率之间均无显著性差异,上述结果表明,有限总体抽样和批量量保证抽样方法均能反映总“四苗”覆盖率水平,且经济,简便。  相似文献   
5.
史金端  孙莲英 《海南医学》1999,10(4):256-256,256
为更好地了解流动儿童计划免疫管理现况,1997年海南省组织了专题调查,发现流动儿童以县内流动为主,流动儿童上卡率为76.6%,五苗接种率分别为卡介苗69.4%,脊灰糖丸65.1%,百白破63.6%,麻疹59.9%,HBV56.9%,均远未达到目标要求,脊达抗体GMT流动儿童为1:153.20,常住儿童为1:243.61,两者有显著性差异,这表明,加强流动儿垢计划免疫管理,最今后计免工作的重点和难点  相似文献   
6.
目的 了解基层计划免疫工作现状,调查分析工作中存在的主要问题,为改善免疫服务行为、提高预防接种质量提供决策依据。方法 采用按容量比例概率法(PPS法)抽取30个乡镇,对适龄儿童计划免疫疫苗接种质量及基层计划免疫管理、接种单位服务质量进行调查、分析。结果 BCG合格接种率为96.2%,OPV合格接种率为94.1%,DPT合格接种率为92.2%,MV合格接种率为91.7%,“四苗”全程合格接种率为87.1%,乙肝疫苗合格接种率为78.6%;适龄儿童建卡率为94.1%;建证率为76.7%;乡级按要求上报常规免疫报表的占56.6%;乡村医师预防接种能够做到一人一针一管的占77.5%。结论 要通过加大计划免疫经费投入,开展预防接种单位与人员的规范化管理,进行预防接种人员技术培训,在预防接种工作中推广应用自毁型注射器,加强计划免疫督促检查与考核等综合措施来进一步提高全省计划免疫工作质量。  相似文献   
7.
The purpose of this study was to investigate the feasibility of two-dimensional (2D) navigated, interleaved multishot echo-planar imaging (EPI) to enhance kidney diffusion-weighted imaging (DWI) in rats at 7.0 T. Fully sampled interleaved four-shot EPI with 2D navigators was tailored for kidney DWI (Sprague–Dawley rats, n = 7) on a 7.0-T small bore preclinical scanner. The image quality of four-shot EPI was compared with T2-weighted rapid acquisition with relaxation enhancement (RARE) (reference) and single-shot EPI (ss-EPI) without and with parallel imaging (PI). The contrast-to-noise ratio (CNR) was examined to assess the image quality for the EPI approaches. The Dice similarity coefficient and the Hausdorff distance were used for evaluation of image distortion. Mean diffusivity (MD) and fractional anisotropy (FA) were calculated for renal cortex and medulla for all DWI approaches. The corticomedullary difference of MD and FA were assessed by Wilcoxon signed-rank test. Four-shot EPI showed the highest CNR among the three EPI variants and lowest geometric distortion versus T2-weighted RARE (mean Dice: 0.77 for ss-EPI without PI, 0.88 for ss-EPI with twofold undersampling, and 0.92 for four-shot EPI). The FA map derived from four-shot EPI clearly identified a highly anisotropic region corresponding to the inner stripe of the outer medulla. Four-shot EPI successfully discerned differences in both MD and FA between renal cortex and medulla. In conclusion, 2D navigated, interleaved multishot EPI facilitates high-quality rat kidney DWI with clearly depicted intralayer and interlayer structure and substantially reduced image distortion. This approach enables the anatomic integrity of DWI-MRI in small rodents and has the potential to benefit the characterization of renal microstructure in preclinical studies.  相似文献   
8.
Immunization of pregnant women against influenza is a promising strategy to protect the mother, fetus, and young infant from influenza-related diseases. The burden of influenza during pregnancy, the vaccine immunogenicity during this period, and the robust influenza vaccine safety database underpin recommendations that all pregnant women receive the vaccine to decrease complications of influenza disease during their pregnancies. Recent data also support maternal immunization for the additional purpose of preventing disease in the infant during the first six months of life.  相似文献   
9.
In fMRI, subject motion can severely affect data quality. This is a particular problem when movement is correlated with the experimental paradigm as this potentially causes artefactual activation. A method is presented that uses linear regression, to utilise the time course of an image acquired at very short echo time (TE) as a voxel‐wise regressor for a second image in the same echo train, that is acquired with high BOLD sensitivity. The value of this approach is demonstrated using task‐locked motion combined with visual stimulation. Results obtained at both 1.5 and 3 T show improvements in functional activation maps for individual subjects. The method is straightforward to implement, does not require extra scan time and can easily be embedded in a multi‐echo acquisition framework. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
10.
《Vaccine》2015,33(31):3673-3677
BackgroundRubella is endemic in Vietnam with epidemics occurring every 4–5 years. In 2011, Vietnam experienced the large nationwide rubella epidemic. During the rubella epidemic, many infants born with congenital rubella syndrome (CRS) were identified and reported from the neonatal units or cardiology departments of the national hospitals. To understand the burden of CRS, National Expanded Program on Immunization (NEPI) established sentinel CRS surveillance system.MethodThree national paediatric hospitals in Hanoi and Ho Chi Minh City (HCMC) were selected as CRS sentinel surveillance sites. Blood specimens from the infants were collected for rubella specific IgM and ELISA testing was performed at the national measles and rubella laboratory.ResultsFrom January 2011 to December 2012, 424 infants with suspected CRS were identified and reported. Among them 406 (96%) had specimens obtained, 284 (70%) cases were IgM positive including 279 laboratory confirmed CRS and 5 Congenital Rubella Infection (CRI). 13 cases were clinically confirmed and 127 (30%) were discarded. Total 292 infants were confirmed as CRS. Of the 292 infants with CRS, 69% of mothers had a history of “fever and rash” during pregnancy, of which 85% was in the first trimester. The most common clinical defects were congenital heart disease and cataract(s). However, 81.9% of the infants had a combination of major and minor signs and symptoms. Low birth weight in full term infants with confirmed CRS was observed in 114 infants (39%).ConclusionsThe newly established CRS sentinel surveillance system documented the significant burden of CRS in Vietnam and provided evidence to the policy makers for the introduction of rubella containing vaccine (RCV) into Vietnam. This report highlights the importance of countries with rubella epidemic to establish CRS surveillance rapidly in order to support the introduction of RCV into the routine Expanded Programme on Immunization (EPI) immunization.  相似文献   
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