三种仪器测量白内障眼生物学参数的比较

目的:比较最新的IOL Master 700与已广泛应用的IOL Master 500及A型超声测量白内障眼生物学参数的一致性,分析评价IOL Master 700在白内障术前检查中的测量优势。方法:前瞻性研究。随机选取2018-04-05/04-20于我院住院行白内障超声乳化摘除及人工晶状体植入手术的年龄相关性白内障患者共52例100眼(其中4例为单眼),对所有患者分别采用IOL Master 700、IOL Master 500、A型超声波(A超)进行检查,获取眼轴长度(AL)、角膜曲率(Km)、中央前房深度(ACD)、角膜横径(W-W)、瞳孔直径(P)等参数。结果:IOL Master 700、IOL Master 500、A超对AL和ACD的检出率分别为98%、87%、99%和100%、99%、99%;IOL Master 700、IOL Master 500对Km的检出率分别为100%、99%;对W-W及P的检出率均为99%。其中高度近视伴后巩膜葡萄肿且AL≥26mm的24眼,IOL Master 700、IOL Master 500、A超的AL检出率分别为96%、79%、96%。三种设备间测得的AL、ACD有差异(F=11.58,P=0.03;F=12.46,P=0.02),Km、W-W、P的参数无差异(均P>0.05)。三种设备对AL测量的平均差值:IOL Master 700和IOL Master 500为0.05±0.12mm,IOL Master 700和A超为0.16±0.14mm;三种设备对AL≥26mm的AL测量的平均差值:IOL Master 700和IOL Master 500为0.17±0.16mm,IOL Master 700和A超为0.55±0.22mm,IOL Master 500和A超为0.11±0.17mm。Pearson相关性分析显示各设备间在AL测量结果中具有较高的相关性,IOL Master 500与IOL Master 700(r=0.85,P=0.03);IOL Master 500与A超(r=0.69,P=0.02);IOL Master 700与A超(r=0.61,P=0.03);通过Bland-Altman法对各设备的AL数据进行一致性分析,显示结果的一致性较好。结论:三种设备的不同眼部生物测量结果一致性较高。IOL Master 700对AL的检出率高于IOL Master 500;同时在高度近视伴后巩膜葡萄肿的AL测量中,IOL Master 700测量的精确性及可靠性更高。与传统检查设备相比,IOL Master 700更好的穿透力和精准度可以提供更加精确的测量参数。

Clinical significance of NT-proBNP, myocardial enzymes, and inflammatory cytokines in diagnosis of acute coronary syndrome

Objective:To explore the clinical significance of NT-proBNP, myocardial enzymes, and inflammatory cytokines in diagnosis of acute coronary syndrome (ACS).Methods: A total of 120 patients with ACS confirmed by CAG who were admitted in our hospital from December, 2014 to December, 2016 were included in the study and divided into UAP group (n=28), NSTEMI group (n=41), and STEMI group (n=51) according to different lesion degrees. Moreover, 40 cases with negative CAG results were served as the control group. The standard Judkins method was used for CAG examination. Multi-position projection was performed to confirm the coronary lesion degrees. The peripheral venous blood was collected on admission, and the serum was separated. The fluorescence immunoassay was used to detect NT-proBNP and CK-MB levels. The chemiluminiscence was used to detect cTnI level. The immunoturbidimetry was used to detect hs-CRP level. ELISA was used to detect IL-18, TNF-α, and MMP-9 levels.Results:The serum NT-proBNP, CK-MB, cTnI, hs-CRP, IL-18, TNF-α, and MMP-9 levels were graudally increased in the control group, UAP group, NSTEMI group, and STEMI group, and the comparison among each group was statistically significant.Conclusions: The combined detection of serum NT-proBNP, CK-MB, cTnI, hs-CRP, IL-18, TNF-α, and MMP-9 is of great significance in diagnosis of ACS, evaluation of severity degree, risk stratification, and formulation of therapeutic schemes.

Efficient Side-chain Modification of Dextran via Base-catalyzed Epoxide Ring-opening and Thiol-ene Click Chemistry in Aqueous Media

In this study, a novel approach by combining base-catalyzed epoxide ring-opening and thiol-ene click chemistry is presented for the side-chain modification of dextran. The vinyl-modified dextran is prepared by a basic epoxide ring opening reaction of allyl glycidyl ether in 0.1 mol/L NaOH, followed by thiol-addition click reaction of three model sulfhydryl compounds using water-soluble Irgacure 2959 as the photoinitiator, leading to side-chain functionalized dextran modified with carboxyl, bidentate dicarboxyl or amino groups. This is the first example of combining epoxide ring-opening and thiol- ene click chemistry for side-chain modification of dextran in aqueous media. Importantly, it may also be extended as a convenient and efficient method for the side-chain modification of other polysaccharides.

Periodic synchronization in a system of coupled phase oscillators with attractive and repulsive interactions

In this study we investigate the collective behavior of the generalized Kuramoto model with an ex- ternal pinning force in which oscillators with positive and negative coupling strengths are conformists and contrarians, respectively. We focus on a situation in which the natural frequencies of the oscilla- tors follow a uniform probability density. By numerically simulating the model, it is shown that the model supports multistable synchronized states such as a traveling wave state, π state and periodic synchronous state： an oscillating π state. The oscillating π state may be characterized by the phase distribution oscillating in a confined region and the phase difference between conformists and contrar- ians oscillating around π periodically. In addition, we present the parameter space of the oscillating state and traveling wave state of the model.

A united tension/compression asymmetry micro-mechanical model for nickel-base single-crystal alloys

In recent years, the micro-deformation mechanisms of the tension/compression behavior for nickel-base single-crystal superalloys have been studied extensively and general agreements have been derived. Based on these researches, a new model called united tension/compression asymmetry micro-mechanical model (UTCAM) has been proposed, which can effectively estimate the initial yield strength of nickel-base single-crystal (SC) superalloys under different loading directions. Considering the combined effects of octahedral slip system and cubic slip system, slip control factor is introduced in the UTCAM to determine the type of the open slip system of nickel-base single-crystal superalloys during deformation, thus making this model cover a rather wide range of application. Furthermore, the UTCAM is applied to hot tension and compression tests of three typical nickel-base SC superalloys (PWA1480-593 ℃, RENE N4-760 ℃ and DD407-760 ℃). The predicted initial yield strengths of the nickel-base SC superalloys are in good agreement with the experimental results, and the UTCAM proves to be effective.