继发性三尖瓣反流的治疗策略分级及其手术效果

目的:旨在随访继发性三尖瓣反流采用不同策略分级治疗后的疗效,验证策略分级的可行性,并总结影响三尖瓣反流复发的因素。方法:选取左心瓣膜疾病合并继发性三尖瓣反流的患者217例。根据三尖瓣瓣环直径指数和瓣叶闭合高度,把三尖瓣反流情况分为Ⅰ、Ⅱ、Ⅲ、Ⅳ四级,结合术前反流程度、肺动脉压力等选择最终三尖瓣成形方法。随访术后1周、术后近期(3~12个月)及术后中期(13~96个月)的三尖瓣功能。结果:共有Ⅰ级患者66例,30.3%未给于三尖瓣同期处理,63.6%采用线性Devega成形;Ⅱ级患者73例,82.2%采用线性Devega成形,17.8%使用成形环处理;Ⅲ~Ⅳ级患者78例,70.5%使用成形环。术后中期随访患者113例(52.1%),平均随访时间(45.0±21.9)个月。术后中期与术前比较,左心房前后径[(49.0±11.4)mm vs(53.5±12.7)mm]、肺动脉收缩压[(32.4±8.6)mmHg vs(49.1±18.7)mmHg,1 mmHg=0.133 kPa]、三尖瓣瓣环直径指数[(17.2±2.0)mm/m2 vs(23.0±3.7)mm/m2]和瓣叶闭合高度[(3.3±1.1)mm vs(4.5±2.1)mm]均明显减低(P均<0.0001)。最终共9例患者再次出现中量及以上程度三尖瓣反流,1例是Ⅰ级患者,余下8例均是Ⅲ~Ⅳ级患者。结论:继发性三尖瓣反流采用不同策略分级治疗,可以获得较满意的术后疗效,避免患者术后严重反流复发,有效降低三尖瓣再次手术的可能性。     

基于比率距离的自适应超声图像去噪方法

针对超声图像噪声的瑞利分布特性,使用一种新的自适应超声图像去噪方法,改进固定窗口包含边缘时无法做到沿边缘方向滤波的不足。采用可自由伸缩的自适应滤波窗口,首先针对瑞利分布的噪声引入比率距离,得到超声图像像素间的相似度距离,然后考虑像素的邻域图像块均值,解决相似度距离之间比较的问题,最后像素根据新的相似度距离进行八方向伸展,得到不规则形状的滤波窗口进行去噪。用仿真超声图像和临床超声图像进行实验,图像评价指标结果表明该算法优于经典算法,更适用于去除超声图像的斑点噪声,在去除噪声的同时能够较好地保留细节边缘。     

光源距离对6种LED固化灯光强度衰减的影响

目的:评估6种LED固化灯光照射强度随光源距离的增加出现衰减的程度。方法:选择6种LED光固化灯:配置标准光导棒的Bluephase、Bluephase C8和Elipar S10,配置聚光透镜的Ascent PX,配置涡轮光导棒的Demi和Ti-Lite GT-1500。使用光强测量仪在距光源0、1、2、3、4、5 mm测量光固化灯的光照射强度,每一距离测量10次,并计算光强度平均值及相应的光强度衰减率。结果:6种固化灯初始光强度分别为859 m W/cm2(Bluephase C8)、1 121 m W/cm2(Bluephase)、1 133 m W/cm2(Elipar S10)、1 300 m W/cm2(Ascent PX)、1 497 m W/cm2(Demi)和1 192 m W/cm2(Ti-Lite)。除Ascent PX的1~3 mm光源距离外,光源距离每增加1 mm,6种固化灯的光照射强度均出现显著降低(P<0.05)。距离光源5 mm时,只有Bluephase、Elipar S10和Ascent PX的光强度超过了400 m W/cm2,光强度衰减率分别为56.7%、58.7%、53.8%,明显低于Bluephase C8(66%)、Demi(78.8%)和Ti-Lite(>72.2%)。结论:临床中应尽可能选用高强度LED固化灯并延长照射时间以弥补光源距离增加所造成的光强度衰减,建议选择配置标准光导棒或聚光透镜的高强度LED光固化灯。     

Predictive value and reference ranges of anogenital distance for determining fetal gender in the first trimester: A retrospective cohort study

Objectives:To assess the usefulness of sonographically measured anogenital distance (AGD) in predicting fetal gender in Saudi fetuses during the first trimester and to provide normal reference centiles for AGD.Methods:A retrospective cohort study was conducted at King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia between November 2020 and May 2021. The ultrasound scans of 313 singleton pregnancies between 11–13 plus 6 gestational weeks and their gender-at-birth were collected. Anogenital distance was measured from the inferior base of the genital tubercle to the rump. Binominal logistic regression and receiver operating characteristic curves (ROC) evaluated the predictive performance of AGD for determining fetal gender.Results:There was a significant difference of approximately 15% in mean AGD between female (5.92 mm [95% CI= 6.70, 6.14]) and male (6.80 mm [95% CI= 6.61,7.00]) fetuses (p<0.001). Anogenital distance significantly correlated with gestational age (r=0.573, p<0.001) and crown-rump length (r=0.562, p<0.001). The logistic regression determined AGD as a significant predictor of fetal gender (p<0.001). However, ROC analysis showed that overall accuracies were low at 68% (p=0.001) for 11 weeks, 70% (p<0.001) for 12 weeks, and 64% (p=0.017), and for 13 weeks. The average AGD of our Saudi cohort was longer than what the literature reported from other populations.Conclusion:The first-trimester ultrasound evaluation of AGD was feasible and reliable. It showed a difference between the genders but did not yield high predictive accuracy. Future research should consider racial factors when evaluating AGD.     

不同地理居群新塔花的ITS2和psbA-trnH序列及聚类分析

目的:分析18个不同地理居群新塔花的内转录间隔区(ITS)2和psbA-trnH序列,为其种质资源评价和基原药用植物遗传多样性分析提供参考。方法:试剂盒法提取新塔花基因组DNA,聚合酶链式反应(PCR)扩增ITS2和psbA-trnH间隔区序列,双向测序,拼接,基于Kimura两参数模型(K2P)构建邻接法(NJ)系统发育树。结果:不同地理居群新塔花ITS2和psbA-trnH序列均有种内差异。ITS2序列长度平均为236 bp,检测有9个单倍型,遗传距离为0～0. 022,不同地理居群新塔花聚为两支,XTH3,XTH6,XTH9等10个地理居群聚为一支,XTH4,XTH5,XTH10等8个地理居群聚为另一支。除XTH6的psbAtrnH序列存在6 bp缺失外,其他地理居群的psbA-trnH序列长度均为355 bp,检测有4个单倍型,遗传距离为0～0. 023,不同地理居群新塔花聚为两支,XTH1,XTH3,XTH4等12个地理居群聚为一支,XTH14,XTH17,XTH18聚为另一支。基于ITS2+psbA-trnH组合序列的系统发育(NJ)树显示,不同地理居群的新塔花可分为两支,XTH11,XTH12,XTH16等12个地理居群聚为一支,XTH14,XTH17,XTH18聚为另一支。结论:不同地理居群的新塔花地理位置接近或相似,相对遗传距离较小,亲缘关系较为接近,说明不同地理居群新塔花的亲缘关系及其遗传多样性与地理位置相关。     

Regional specificity of cathodal transcranial direct current stimulation (tDCS) effects on spatial-numerical associations: Comparison of four stimulation sites

Based on a theory of impulsive and reflective human behavior, we test the effects of transcranial direct current stimulation (tDCS) targeting either prefrontal or parietal cortex in either hemisphere. In a confirmatory registered report, cathodal tDCS is administered to conceptually reproduce tDCS modulations of implicit spatial-numerical associations, numerical distance effects, and response inhibition. Those cognitive operations are hypothesized to draw on left prefrontal, parietal, and right prefrontal activations, respectively, thereby susceptible to inhibitory, cathodal tDCS across those regions. Vice versa, the mutual regional and behavioral specificity of tDCS effects on these behavioral indices is examined and expected to produce double dissociations. In a mixed within-subjects (baseline, during tDCS, post-tDCS) and between-subjects (target electrode: left/right prefrontal cortex/posterior parietal cortex, or sham tDCS) design, we collect (a) confirmatory data on the robustness of cathodal tDCS effects on three behavioral effects and (b) differential data on the specificity of regional targets in male and female human participants. Results will provide crucial tests of theories of cortical organization implied by implicit associations and explicit regulation, which can direct future brain stimulation studies.     

股浅动脉支架内再狭窄的再干预治疗疗效分析

目的 探讨股浅动脉支架内再狭窄患者再次干预治疗的近期疗效.方法 回顾性分析2011年12月-2013年1月20例股浅动脉支架内再狭窄患者的基本资料、病变特征及再次干预治疗后的症状改善和再狭窄发生情况.结果 20例支架内再狭窄患者就诊时的主要症状为间歇性跛行14例,急性下肢缺血3例,静息痛3例.术前踝肱指数（ankle brachial index,ABI）中位数0.43 （0～0.72）,间歇性跛行距离（238.50±76.80）m.20例患者中65％ （13/20）合并2型糖尿病,45％合并高血压（9/20）,25％合并高脂血症（5/20）.70％ （14/20）为TASCII C／D级病变.再次干预治疗的方法分别为经皮血管腔内成形术（percutaneous transluminal angioplasty,PTA）4例、经皮血管腔内成形术＋支架植入（percutaneous transluminal angioplasty＋stent,PTA＋S）9例、大隐静脉/人工血管旁路术（bypass）3例、斑块旋切治疗（SilverHawk）4例.随访患者14例,平均随访6m （2～18 m）.围手术期未出现死亡、心肌梗死、肾功能不全等并发症,无截肢发生.术后ABI中位数0.69 （0.5～0.85）,与术前ABI相比差异有统计学意义（P＜0.05）.间歇性跛行距离（835.00±217.80）m,（P＜0.01）,术后6m随访时,42.86％患者（6/14）再次出现支架内再狭窄.结论 再次干预治疗可以在近期明显改善支架内再狭窄患者的下肢缺血症状,但仍存在较高的再狭窄率.     

基于Hausdorff距离的CARTO电解剖图与CT曲面配准

我们提出一种全自动、高精度的CARTO电解剖图(EAM)与CT曲面的配准算法。算法首先以基于主轴的方法粗配准EAM与CT曲面,然后再以基于Hausdorff距离的方法进一步实现EAM与CT曲面精配准。实验结果表明,相对Carto-Merge配准软件以及随机配准算法,基于Hausdorff距离的配准算法能获得更稳定且更精确的EAM与CT曲面配准效果,同时算法完全自动,基于Hausdorff距离的EAM与CT曲面配准算法能很好地满足房颤消融手术的临床应用需求。