彩超联合人绒毛膜促性腺激素β诊断早期宫外孕的研究

本文探讨经阴道彩色多普勒超声、人绒毛膜促性腺激素β(β-hCG)在早期异位妊娠诊断中的价值。选取异位妊娠患者78例作为观察组,根据超声影像特征,其中环状征型、混合包块型和典型孕囊型分别为15例、24例和39例;选取正常妊娠者140例作为对照组。两组均行经阴道彩色多普勒超声检查,采用电化学发光法检查血清β-hCG水平。结果显示,与对照组比较,观察组子宫内膜厚度和血清β-hCG水平降低(P<0.05);环状征型、典型孕囊型和混合包块型患者血清β-hCG水平比较差异有统计学意义(P<0.05);血清β-hCG水平联合子宫内膜厚度预测异位妊娠的ROC曲线下面积为0.901(P<0.05)。经阴道彩色多普勒超声联合β-hCG在异位妊娠诊断中有较好的效果,同时异位妊娠患者β-hCG水平与彩超影像特征有一定关系。     

赤道几内亚巴塔地区产妇分娩时间分析

为分析赤道几内亚巴塔地区产妇分娩时间有无集中趋势 ,准确记录了 3 0 66例单胎足月顺产产妇分娩时间 ,并进行了统计学分析。结果表明 ,y =0 2 3 64 ,x =-0 1 0 7865,r =0 2 598,仭=1 1 4 52°,s=94 0 7,仭 >S ,故P <0 0 0 5。结论 :该地区分娩时间存在集中趋势 ,以当地 7时3 8分为中心 (P <0 0 0 5) ,提示援外医务人员予以重视。     

音强斜率特性区别同卵双胞胎语音的实验研究*

为了寻找司法话者识别中区别同卵双胞胎语音的有效参量,该文利用音节音强的斜率特性对同卵双胞胎语音进行了实验研究。结果发现,在90%的置信度下,所有实验的双胞胎语音均能够被音节音强斜率予以区别,并且音强下降斜率的区别力明显高于音强上升斜率的区别力。因此得出结论,音节音强的斜率特性具有比音节间相对音强与相对时长二者联合检验更强的区别力,可以作为区别同卵双胞胎语音的有效参量。     

Speaking Fundamental Frequency in Monozygotic and Dizygotic Twins

The speaking fundamental frequency (SFF) and the intraindividual variation of the SFF during the reading of a Dutch standard text were measured in 30 female monozygotic twins (MT) and 30 dizygotic twins (DT), aged 15–29 years. A control group was created that consisted of 30 nonrelated paired individuals of equal age. Studying the intrapair correlation coefficients it seemed that the SFF was similar to a greater degree in MT and to a lesser degree in DT, while there was no correlation at all in nonrelated peers. These results are compatible with a genetic basis for the SFF. On the other hand, the intraindividual variation of the SFF was highly similar in MT and in DT (but not in nonrelated peers), so that for this parameter it was not possible to discern the influences of genetic disposition and shared environment.     

Mineralogical changes of bioapatite in femoral bones of mice during pregnancy

Mineralogical changes and solubility of bioapatite in mice cortical bones (2- and 5 months old) were investigated by Raman spectroscopy and inductively coupled plasma spectrometry in this study. The Raman analyses show that the full width at half maximum values of the 960?cm^?1 peak exhibit a slight increase during mouse pregnancy, which suggests slightly decreasing crystallinity. Additionally, aging significantly increases the solubility of bone bioapatite. The 1070?cm^?1 peak indicates the enriched carbonate incorporation during aging from 2 to 5 months. The elevated solubility of bioapatite and low bone density are consistent with the low crystallinity of bioapatite.     

双盘工作电极参比电位采样快扫伏安方法

报道一种双铂盘工作电极、相应的毛细管参比电极和竖直式电化学池设计并用于快速循环伏安测量.双工作电极包括一个常规工作电极,一个辅助工作电极.后者在使用中接地,仅提供参比电位来控制工作电极的电位.参比毛细管尖端安设在接近辅助工作电极的位置上;用0.3mm直径Pt盘工作电极,在电位扫描速度高达10kV/s都可以得到类似于100%iR补偿的伏安曲线,而不必使用iR补偿电路.本文围绕高扫速伏安法中工作电极电位的准确控制问题做了一些初步的探讨.     

A crystal plasticity theory for latent hardening by glide twinning through dislocation transmutation and twin accommodation effects

Imagine a residual glide twin interface advancing in a grain under the action of a monotonic stress. Close to the grain boundary, the shape change caused by the twin is partly accommodated by kinks and partly by slip emissions in the parent; the process is known as accommodation effects. When reached by the twin interface, slip dislocations in the parent undergo twinning shear. The twinning shear extracts from the parent dislocation a twinning disconnection, and thereby releases a transmuted dislocation in the twin. Transmutation populates the twin with dislocations of diverse modes. If the twin deforms by double twinning, double-transmutation occurs even if the twin retwins by the same mode or detwins by a stress reversal. If the twin deforms only by slip, transmutation is single. Whether single or double, dislocation transmutation is irreversible. The multiplicity of dislocation modes increases upon strain, since the twin finds more dislocations to transmute upon further slip of the parent and further growth of the twin. Thus, the process induces an increasing latent hardening rate in the twin. Under profuse twinning conditions, typical of double-lattice structures, this rate-increasing latent hardening combined with crystal rotation to hard orientations by twinning is consistent with a regime of increasing hardening rate, known as Regime II or Regime B. In this paper, we formulate governing equation of the above transmutation and accommodation effects in a crystal plasticity framework. We use the dislocation density based model originally proposed by Beyerlein and Tomé (2008) to derive the effect of latent hardening in a transmuting twin. The theory is expected to contribute to surmounting the difficulty that current models have to simultaneously predict under profuse twinning, the stress-strain curves, intermediate deformation textures, and intermediate twin volume fractions.