Effect of chorionic villus sampling on utilization of prenatal diagnosis in women of advanced maternal age

The effect of the introduction of chorionic villus sampling on the utilization rate of prenatal diagnosis in advanced maternal age was studied during the period 1 January 1985-1 January 1991. On the first of January 1985, the age limit for prenatal diagnosis in The Netherlands was lowered from 38 to 36 years of age. The overall uptake rate during the studied period increased significantly, but only because of the increased uptake rate in the group 36 and 37 years. In the maternal age group of 42 years and older, an uptake rate as low as 15.9% was established. This was mainly determined by the relatively high percentage (73.0%) of women from ethnic minorities in this age group. The number of CVS procedures increased significantly during the study period, but the utilization rate was not influenced, since the number of amniocenteses decreased accordingly. An increase in acceptability of prenatal diagnosis by women of advanced maternal age due to early testing and early termination of pregnancy could not be substantiated in the present study.     

甲苯扩散采样的定量方法

为探讨对载人航天舱内空气污染进行监测的采样方式，本文通过对甲苯－空气混合气的扩散采样的定量研究，提出了扩散采样定量方法、步骤及其方法的有效性，讨论了环境因素对采样定量的影响。本方法对多组分有害气体－空气混合气的扩散采样定量有参考价值。     

胰岛内分泌肿瘤中α-HCG蛋白及mRNA表达的研究──应用免疫组化及原位PCR技术对52例的观察

应用免疫组化对52例胰岛内分泌肿瘤（PET）α－HCG蛋白表达进行观察；并用原位PCR技术中对其α-HCGmRNA的表达进行观察。结果发现α-HCG在各类正常胰岛细胞中未见蛋白及基因的阳性表达。在良性及恶性PET中α-HCG蛋白检出率分别为17．9％（5／28）及58．3％（14／24）。在α－HCG抗原阳性的PET中应用原位PCR技术均可见有α－HCGmRNA的表达。说明该类肿瘤细胞具有合成α-HCG的能力。对α－HCG在PET中表达的临床病理意义进行了研讨。     

Asymmetric sampling along kslice-select in two-dimensional multislice MRI

Reduction of the slice-select refocusing gradient in two-dimensional multislice imaging results in asymmetry of the k-space representation of collected data along the slice-select direction. Standard methods of partial Fourier reconstruction developed for other methods of asymmetric k-space sampling can be used to reconstruct these data with final through-plane resolution smaller than the collected slice thickness. This method can be used for reducing scan time in the same manner as asymmetric sampling in the phase-encoded direction. In addition, the reduced refocusing gradient reduces minimum TE and motion artifacts in the same manner as for asymmetric sampling in the frequency-encoded direction (fractional echoes). Results using a resolution phantom and a flow phantom illustrate these concepts.     

血绒毛膜促性腺激素β对早期诊断异位妊娠的价值

目的　探讨血绒毛膜促性腺激素 β (β -HCG)在早期诊断异位妊娠的价值。 方法　采用前瞻性方法对比研究了不同停经周数的异位妊娠和先兆流产患者的血 β-HCG值 ,取静脉血以BayerAcs180HCG双抗体夹心光化学测定法测定 β-HCG值。 结果　 84例异位妊娠 β-HCG值与停经天数无显著相关 (r=0 2 1,P =0 0 6 38) ,78例先兆流产的 β-HCG值与停经天数正相关 (r =0 5 9,P =0 0 0 0 1)。两组的平均 β -HCG分别为 2 0 14 5U/L和 4 172 6U/L ,异位妊娠组的平均 β-HCG值显著低于流产组 ,P <0 0 0 1,差异有极显著性。 结论　相对较低的血 β-HCG值和较低幅度的上升变化 ,对异位妊娠的早期诊断有肯定价值。     

PC机与C8051F000串行通信在心音数据采集中的实现

分析了心音数据采集系统对上下位机之间数据通信接口的需要,介绍系统设计思想、硬件接口电路及单片机C8051F000编程实现方法,并在上位机中讨论如何使用C Builder和WindowsAPI函数进行接口编程,给出实用程序。     

应用纤维支气管镜采样对肾移植患者肺部感染诊断的意义

目的评估应用纤维支气管（ＦＯＢ）采样对肾移植患者并发肺部感染的诊断价值及其安全性。方法对１９例肾移植术后出现发热、肺部浸润拟诊为肺部感染患者行ＦＯＢ采样（包括防污染样本毛刷、支气管刷检、支气管冲洗、支气管肺泡灌洗、支气管肺活检），就采样标本行除巨细胞病毒（ＣＭＶ）外的其他各种病原体检测。结果１３例明确诊断，阳性率６８．４％。普通细菌７例共９株（绿脓杆菌４株、肺炎克雷伯杆菌、阴沟杆菌、产碱杆菌、金黄色葡萄球菌、表皮葡萄球菌各１株）；结核杆菌３例；曲菌１例；卡氏肺孢子虫２例。全部患者均能耐受经ＦＯＢ采样，无并发症产生。病死率为３６．８％，明确与未明确病原诊断的病死率分别为１５．４％和６６．７％（Ｐ＜０．０１）。结论ＦＯＢ采样对于肾移植并发肺部感染具有一定的诊断价值，安全。     

Bayesian图解模型—直线回归

Bayesian图解模型是综合Bayesian理论,图论的观点及MCMC模拟方法的复合模型,现通过具体实例系统地介绍该模型的基本思想,建模求解及推论过程,体现Bayesian图解模型的优点与不足。