改良ABC设计的非球面IOL植入对白内障患者术后视觉质量的影响

目的:评估改良非球面平衡曲线(ABC)设计的非球面人工晶状体(IOL)植入术后的视觉质量,同时进行临床IOL选择的影响因素分析,指导患者的IOL选择方案。方法:前瞻性病例对照研究。选取拟行白内障超声乳化联合折叠式IOL植入术的单纯性白内障患者67例74眼,其中观察组植入改良设计IOL 23眼(HOYA Vivinex XY1组),对照组植入传统设计IOL 51眼(Tecnis ZCB00组27眼,IQ SN60WF组24眼),术后1wk, 1mo测量裸眼视力及最佳矫正视力、不同瞳孔直径下(3、4、5、6mm)全眼球差及彗差、不同瞳孔直径(3、4、5mm)下的调制传递函数(MTF)曲线、客观散射指数(OSI)、眼内散射光值Log(s)及对比敏感度。对所得的数据进行统计学分析。结果:三组术后1wk, 1mo裸眼视力及最佳矫正视力均较术前显著提高,组间均无差异(P>0.05)。术后全眼球差值比较,术后1wk, 5、6mm瞳孔直径下三组存在差异(P=0.045、0.037),术后1mo 6mm瞳孔直径下三组存在差异(P=0.042)。全眼彗差值比较,术后1wk, 1mo 5、6mm瞳孔直...     

Investigation of the Thermodynamic Transformation and Rare Earth Microalloying of a Medium Carbon-Medium Alloy Steel for Large Ball Mill Liners

The medium carbon-medium alloy steel was developed for the manufacture of large ball mill liners and sports equipment. In this study, the continuous cooling transformation curve of a novel type of medium carbon-medium alloy steel was measured with a thermal simulation machine; based on this curve, the hardening and tempering processes were optimized. The steel was then complex modified with alkaline earth and rare earth alloys. The mechanical properties of the treated steel were tested. The microstructure of the steel was analyzed by metallographic microscopy, X-ray diffraction, scanning electron microscopy and transmission electron microscopy, and the wear surface of the steel was analyzed by a three-dimensional morphometer. After high-temperature tempering, the microstructure transformed into tempered sorbite, which possesses good mechanical properties and can adapt to working conditions that require high strength and toughness. Rare earth or alkaline earth modification of the medium carbon-medium alloy steel promoted microstructural uniformity and grain refinement and improved the mechanical and anti-wear properties.     

Rotor-Gene链融解曲线法甲基化标记筛选技术的建立

目的:建立基于Rotor-Gene的链融解曲线法的甲基化标记筛选技术,分析各种影响因素,评估其实用性.方法:克隆Hela细胞雄激素受体基因外显子-1的Bisulfite-PCR产物,挑出经测序证实的可以代表不同甲基化程度的一组质粒,并以之为模板,在Rotor-Gene 3 000实时定量PCR仪进行扩增和链融解,分析融链温度、链融解曲线与甲基化程度、甲基化模式的相关性及各种影响因素.结果:基于Rotor-Gene 的链融解曲线法,不仅可以区分甲基化与非甲基化,而且能够鉴别片段内细微的甲基化差异;主要的影响因素有升温幅度、缓冲液离子强度、产物浓度等.结论:基于Rotor-Gene 的链融解曲线法,可以集扩增和链融解于一体,是一种经济简便的甲基化分析技术,可用于样品的甲基化筛选.     

液相连续反应釜反应效果预测

液相连续反应釜反应效果可如下进行预测。通过实验室装置测定并绘制拟定条件下的反应动力学曲线。把生产釜模拟为带死角和短路的理想釜,用水作介质在生产釜中进行流动模型试验,测量一系列停留时间分布密度函数,得到两个模型参数,并建立操作线方程。反应动力学曲线和操作线的交点为此液相连续反应釜的预测结果。     

Cumulative exposure to high estradiol levels during the follicular phase of IVF cycles negatively affects implantation

Purpose: To investigate the effect of the cumulative exposure to estradiol (E₂) during the follicular phase on IVF outcome. Methods: Patients were stimulated with recombinant FSH after GnRH agonist suppression and had a day 3-embryo transfer. Estrogen exposure was determined as the area under the curve (AUC) for serum E₂ levels measured from the first day of stimulation through the day after hCG administration. Results: E₂ AUC thresholds for 10th and 90th percentiles were 4704 pg/ml and 16338 pg/ml, respectively. The pregnancy and implantation rates were highest in the 10th–90th percentile group, and were statistically higher in this group than in the >90th percentile group (54.6% vs. 33.3% and 24.8% and 12.9%, respectively, for pregnancy and implantation rates, P < 0.05). Recovered mature oocytes, fertilization, and number and mean score of transferred embryos were similar. Conclusions: High cumulative E₂ exposure during the follicular phase of IVF cycles has detrimental effects on implantation.     

Neural network-based computer-aided diagnosis in distinguishing malignant from benign solitary pulmonary nodules by computed tomography

Background Computer-aided diagnosis (CAD) of lung cancer is the subject of many current researches. Statistical methods and artificial neural networks have been applied to more quantitatively characterize solitary pulmonary nodules (SPNs). In this study, we developed a CAD scheme based on an artificial neural network to distinguish malignant from benign SPNs on thin-section computed tomography (CT) images, and investigated how the CAD scheme can help radiologists with different levels of experience make diagnostic decisions.Methods Two hundred thin-section CT images of SPNs with proven diagnoses (135 small peripheral lung cancers and 65 benign nodules) were analyzed. Three clinical features and nine CT signs of each case were studied by radiologists, and the indices of qualitative diagnosis were quantified. One hundred and forty nodules were selected randomly to form training samples, on which the neural network model was built. The remaining 60 nodules, forming test samples, were presented to 9 radiologists with 3–20 years of clinical experience, accompanied by standard reference images. The radiologists were asked to determine whether a nodule was malignant or benign first without and then with CAD output. Diagnostic performance was evaluated by receiver operating characteristic (ROC) analysis.Results CAD outputs on test samples had higher agreement with pathological diagnoses (Kappa=0.841, P&lt;0.001). Compared with diagnostic results without CAD output, the average area under the ROC curve with CAD output was 0.96 (P&lt;0.001) for junior radiologists, 0.94 (P=0.014) for secondary radiologists and 0.96 (P=0.221) for senior radiologists, respectively. The differences in diagnostic performance with CAD output among the three levels of radiologists were not statistically significant (P=0.584, 0.920 and 0.707, respectively). Conclusions This CAD scheme based on an artificial neural network could improve diagnostic performance and assist radiologists in distinguishing malignant from benign SPNs on thin-section CT images.     

RUMA and RUPCR in children with Henoch–Schonlein purpura

ObjectiveThe aim of this study was to compare the qualitative and quantitative targets in the detection of proteinuria in children with HSP.MethodsThree hundred and forty children were taken as the research subjects. Qualitative and a series of quantitative indicators of urine protein were tested.ResultsThe qualitative and quantitative of protein in 340 children were analyzed retrospectively. Correlation analysis found that 24hUTP had a strong correlation with age, RUMA, RUPCR, and qualitative urine occult blood (p < 0.01, for all). After regression analysis, RUMA and RUPCR were still significantly correlated with 24hUTP (p < 0.01). At the same time, RUMA and RUPCR had good diagnostic accuracy for proteinuria. When the RUPCR ratio was set as 0.415, the diagnostic sensitivity was 83%, and the specificity was 98.7%. When RUMA was set as 68.215, the sensitivity was 94.3% and the specificity was 96.2%.ConclusionCompared with 24hUTP, RUMA and RUPCR had high sensitivity and specificity for monitoring proteinuria in children with HSP.     

聚苯乙烯在环己烷、甲基环己烷系统中的液液平衡 Ⅰ．雾点线和旋节线的实验测定

建立了高分子溶液雾点线和旋节线的测定方法及其实验装置，测定了环己烷－聚苯乙烯（Ｍ＿ｗ＝１９００００；Ｍ＿ｗ／Ｍ＿ｎ＝１．０４）、甲基环己烷－聚苯乙烯（Ｍ＿ｗ＝３７９００；Ｍ＿ｗ／Ｍ＿ｎ＝１．０１）系统的雾点线和旋节线，经与文献数据比较，表明本方法及其装置是可行的。