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111.
The first universal hepatitis B vaccination program for newborns in the world was launched in Taiwan in July 1984. Most studies on the effectiveness of hepatitis B vaccination focused on the seroprevalence of HBs Ag among children under 14 years old. Only few studies focused on the seropositivity of anti-HBs among adolescents aged 15–18 years old. The present study aimed to evaluate the impact of the nationwide hepatitis B vaccination program on the immunity to HBV infection and the necessity of boost among adolescents. In this study including eight annual seroprevalence surveys from 2000 to 2007, 2342 college entrants (1589 15-year-olds in group I and 753 18-year-olds in group II) and 1851 university freshmen (18-year-olds in group III) participated. Subjects identified anti-HBs, HBs Ag and anti-HBc negative were given boost three doses of HBV vaccine. The HBs Ag seroprevalence was 11.6%, 3.5% and 1.0% for participants who were born before 1984, 1984–1986 and after 1986. The anti-HBs-seropositive rates were significantly higher in group II (83.1%) than in group I (53.0%) and group III (53.5%). All 572 participants who were seronegative for anti-HBs, HBs Ag and anti-HBc became anti-HBs-seropositive after catch-up vaccination. It is concluded that the anti-HBs-seropositive rate decreased to 50% in 15 years after vaccination, and boost vaccination was 100% effective. The necessity and age for boost among anti-HBs negative adolescents and the timing of the first immunization should be further evaluated.  相似文献   
112.
目的:探讨宫腔镜检查术在辅助生殖技术中应用的重要性。方法:对150例拟行辅助生殖技术的不育妇女行常规宫腔镜检查。结果:宫腔镜150例中47例(31%)有镜下异常,其中:子宫内膜息肉或息肉样增生18例(12%),子宫内膜单纯性增生17例(11%),子宫畸形7例(5%),宫腔粘连狭窄3例(2%),子宫内膜结核1例(0.7%),子宫黏膜下肌瘤或腺肌瘤1例(0.7%)。以宫腔镜诊断为标准,阴道超声诊断敏感性、特异性、阳性预测值、阴性预测值、准确率分别为66%(31/47)、98%(101/103)、94%(31/33)、86%(101/117)、88%(132/150),子宫造影分别为26%(12/47)、100%(95/95)、100%(12/12)、73%(95/130)、75%(107/142)。结论:宫腔镜检查术具有良好的可接受性和准确性,应作为辅助生殖技术前的常规检查。  相似文献   
113.
现代医学200词——138.黏附分子   总被引:1,自引:0,他引:1  
喻磊  王心 《日本医学介绍》2005,26(10):479-480
所谓黏附分子是指存在于细胞表面,参与细胞间或细胞与细胞外基质的粘附的分子群的总称。广义来说,纤维连结蛋白、层粘连蛋白、透明质酸等细胞外基质的构成成分也是由细胞分泌并存在于细胞表面,也可归入黏附分子的范畴。但狭义所指的黏附分子是指贯通细胞膜的糖蛋白或构成细胞膜的糖脂质。膜贯通型糖蛋白黏附分子按其构造特征可分为若干家族。在免疫系统中的黏附分子主要分为整合素家族、免疫球蛋白超家族、选择素家族、钙粘素家族、连接蛋白家族以及唾液粘蛋白家族等。  相似文献   
114.
In this work the feasibility of separating fat and water signals using the balanced steady-state free precession (SSFP) technique is demonstrated. The technique is based on the observation (Scheffler and Hennig, Magnetic Resonance in Medicine 2003;49:395-397) that at the nominal values of TE = TR/2 in SSFP imaging, phase coherence can be achieved at essentially only two orientations (0 degrees and 180 degrees ) relative to the RF pulses in the rotating frame, under the assumption of TR < T2, and independently of the SSFP angle. This property allows in-phase and out-of-phase SSFP images to be obtained by proper choices of the center frequency offset, and thus allows the Dixon subtraction method to be utilized for effective fat-water separation. The TR and frequency offset for optimal fat-water separation are derived from theories. Experimental results from healthy subjects, using a 3.0 Tesla system, show that nearly complete fat suppression can be accomplished.  相似文献   
115.
116.
Selecting an appropriate working correlation structure is pertinent to clustered data analysis using generalized estimating equations (GEE) because an inappropriate choice will lead to inefficient parameter estimation. We investigate the well‐known criterion of QIC for selecting a working correlation structure, and have found that performance of the QIC is deteriorated by a term that is theoretically independent of the correlation structures but has to be estimated with an error. This leads us to propose a correlation information criterion (CIC) that substantially improves the QIC performance. Extensive simulation studies indicate that the CIC has remarkable improvement in selecting the correct correlation structures. We also illustrate our findings using a data set from the Madras Longitudinal Schizophrenia Study. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
117.
目的 分析和探讨桡骨远端关节内骨折外固定器治疗的相关机制和原则.方法 笔者采用Orthofix外固定器和国产组合式外固定器治疗桡骨远端关节内骨折45例46肢,以齐藤英彦法对资料完整的37例38肢病例进行分型,分析其影像学表现、损伤和治疗相关机制以及特点.结果 各型复位方向和外固定腕关节位置均与致伤暴力方向相反.骨折愈合时间平均为43 d(37~62 d),平均随访时间14个月(3~56个月),按Dienst标准评估腕关节功能及疗效:优21例22肢,良10例10肢,可6例6肢.结论 闭合复位外固定能很好地解决桡骨远端关节内骨折的治疗问题,特别适用于粉碎型关节内骨折.其治疗原则是复位方向及腕关节外固定位置与损伤机制、移位情形相反,个别骨折块辅以切开复位时须强调有限切开,必须重视部分病例伴有的同侧桡骨中远段骨折和同侧尺骨远段骨折的处理.  相似文献   
118.
Epidemiologic studies have demonstrated that trans fat intake increases the risk of some chronic diseases. We hypothesize that trans fat intake would increase the risk of cardiovascular disease and type 2 diabetes mellitus by changing the lipid profile in plasma, the secretion of adipokines in adipose tissue, and the insulin sensitivity. Accordingly, the major objective of present study was to investigate the effect of dietary intake of trans fat on lipid profile, insulin sensitivity, and adipokine levels in plasma. Two groups of Wistar rats were fed a diet containing 4.5% trans fat or a control diet containing no trans fat for 16 weeks. Fasting glucose level was monitored every 2 weeks. At the end of feeding experiment, blood, heart, kidney, liver, omental adipose tissue, and semitendinosus muscle were collected. The trans fat content in organs, lipid profile, adipokine, insulin, and glucose levels in plasma were analyzed. The trans fat content in adipose tissue, heart, kidney, liver, and muscle of rats fed trans fat were 169.9, 0.6, 1.2, 1.7, and 2.5 mg/g samples, respectively. The trans fat content in these organs contributed to 15.9%, 1.2%, 2.3%, 4.3%, and 6.1% of the total fat, respectively. The plasma glucose level, insulin level, and insulin sensitivity index were not significantly different between the trans fat and control groups. The results indicated that trans fat intake might not be related to insulin resistance. However, lipid profile and plasma adipokine levels were significantly changed after trans fat feeding. The trans fat fed group showed significantly lower total cholesterol and high-density lipoprotein cholesterol levels than the control group. The decreased high-density lipoprotein cholesterol level may indicate the detrimental effect of trans fat intake on lipid profile. Adiponectin and resistin levels were significantly higher in the trans fat group than the control group. Leptin levels were significantly lower in the trans fat group than the control group. The results indicated that dietary intake of trans fat can significantly change the adipokine levels, but the possible links between adipokine level change caused by trans fat intake and metabolic effects of this change need further investigations.  相似文献   
119.
王成荣研究员长于以中医药诊治子宫内膜异位症(EMT),根据其临床经验认为“火热致瘀”是EMT的基本病因、病机,且火热与瘀血互为因果、恶性循环,致使EMT病程缠绵不愈、反复复发。王老据此提出“清热解毒、化瘀散结”的治疗法则,为治疗EMT开辟了另一思路和理论。  相似文献   
120.
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