免散瞳眼底照相在糖尿病视网膜病变筛查中的应用分析

目的:观察并分析免散瞳眼底照相在糖尿病视网膜病变(DR)筛查中的作用,为临床筛查提供依据。方法:选取我院2016-12/2017-11确诊为糖尿病(DM)患者120例240眼为观察对象,由同一操作者逐一进行免散瞳眼底照相、散瞳后7方位眼底照相及眼底荧光血管造影检查(FFA)。以糖尿病视网膜病变国际临床分级为标准,采取盲法由同一医师分别对以上三项检查进行阅片、分级并记录。最后以眼底荧光血管造影检查为金标准,分别对前两种方法与眼底荧光造影的结果进行对比性研究,计算每种方法对不同程度的DR的敏感度、特异度、Youden指数、Kappa值,筛选出简单易行、有效的糖尿病视网膜病变的筛查方法。结果:通过眼底血管造影筛查出糖尿病视网膜病变168眼(70. 0%),散瞳后眼底照相筛查出糖尿病视网膜病变160眼(66. 7%),免散瞳眼底照相筛查出糖尿病视网膜病变156眼(65. 0%)。不同方法筛查出的糖尿病视网膜病变分级结果基本一致,差异无统计学意义(P> 0. 05)。对不同程度糖尿病视网膜病变进行筛查时,免散瞳眼底照相组的敏感度和特异度分别为92. 9%、90. 3%,与散瞳后眼底照相组的结果无明显差异。与金标准组(FFA)比较,其Youden指数(83. 14%)接近于1,结果可靠度高,Kappa=0. 81,检验具有一致性。对中度非增殖期糖尿病视网膜病变进行筛查时,免散瞳眼底照相组的敏感度和特异度的分别是90. 6%、95. 5%,与散瞳后眼底照相结果无明显差异。与金标准组比较,免散瞳眼底照相的Youden指数为86. 09%,结果可靠度高,Kappa=0. 86,检验具有一致性。结论:免散瞳眼底照相作为一种筛查糖尿病视网膜病变的简单、准确率高的可行性方法。此项检查简单易行,无风险,可培训专科技师进行多点操作,借助如今方便的网络传输图像至有经验的眼科医师阅片、诊断,方便快捷,让患者就近诊治,避免了来回奔波的辛劳,对社会具有积极的意义。

全视网膜光凝联合雷珠单抗与曲安奈德治疗糖尿病黄斑水肿的疗效及费用比较

目的:比较分析全视网膜光凝联合雷珠单抗与曲安奈德(TA)玻璃体腔注射治疗糖尿病黄斑水肿的疗效及医疗费用。方法:收集我院糖尿病视网膜病变伴黄斑水肿患者48例48眼。所有患者行全视网膜激光光凝后随机分为两组。雷珠单抗组:玻璃体腔注射雷珠单抗0.5mg,4 wk 1次。共3次。TA组:注射曲安奈德4mg/0.1mL。治疗12wk后若黄斑中心凹视网膜厚度(CMT)≥400μm,则再次注射各组对应药物。随访6mo,对比观察两组患者治疗前及注射药物后的最佳矫正视力(BCVA)、CMT、眼压及相关治疗费用。结果:两组患者BCVA和CMT均无显著统计学差异(P>0.05),不同测量时间点BCVA和CMT具有显著统计学差异,不同治疗方法和时间点BCVA及CMT均存在交互作用(P<0.05)。除了TA组注药后1wk时BCVA较治疗前无明显提高(P=0.33),其余各时间点两组BCVA均较治疗前提高(P<0.05)。治疗12、16wk雷珠单抗组BCVA提高较TA组明显,两组差异有统计学意义(P=0.03、0.045)。雷珠单抗组及TA组CMT注药后较注药前均有降低(P<0.05)。注射后1wk两组之间CMT差异有统计学意义(P<0.01)。除了1例患者需使用降眼压药物,其余两组患者眼压均在正常范围内。治疗12wk内本研究相关诊疗平均费用雷珠单抗组患者为38736元,TA组为5790元。治疗24wk两组平均费用分别为42564元及7053元。结论:短期内全视网膜光凝联合雷珠单抗与曲安奈德玻璃体腔注射均能有效控制DME,两组治疗方法无显著差异,但全视网膜激光联合玻璃体腔注射曲安奈德治疗DME更经济。

蛋白质组学的研究现状及其在2型糖尿病中的应用

蛋白质组学是对基因编码蛋白质进行大规模分析的一门新兴学科。本文概述蛋白质组学的基本技术:双相凝胶电泳、多维液相色谱、生物质谱技术及蛋白质芯片在2型糖尿病(T2DM)中的应用,从而探讨T2DM中与炎症及脂代谢紊乱相关的生物蛋白:C反应蛋白、α2-巨球蛋白、载脂蛋白A1、Clusterin及锌-α-2糖蛋白的研究进展,发现早期诊断T2DM新的特异性标志物及药物作用靶点。

Geology and mineralization of the supergiant Shimensi granitic-type W-Cu-Mo deposit(1.168 Mt)in northern Jiangxi,South China:A Review

The Shimensi deposit is a recently discovered W-Cu-Mo polymetallic deposit located in the Jiangnan porphyry-skarn W belt in South China.The deposit has a resource of 0.74×10^(6)t of WO_(3)accompanied by 0.4×10^(6)t Cu and 28000 t Mo and other useful components like Ga,making it one of the largest W deposits in the world.This paper is aimed to reveal the ore-controlling mechanisms of the Shimensi deposit,involving the role of the ore-related granites,the tectonic background for its formation,and the metallogenesis model.The systematic geological survey suggests multi-types of alteration are developed in the deposit,mainly including greisenization,potassic-alteration,sericitization,chloritization,and silicification.Drilling engineering data and mining works indicate that the Shimensi deposit consists of two main orebodies of I and II.Therein,the W resource has reached a supergiant scale,and the accompanied Cu,Mo,Au,Bi,Ga,and some other useful components are also of economic significance.The main ore-minerals consist of scheelite,wolframite and chalcopyrite.Disseminated mineralization is the dominant type of the W-Cu-Mo polymetallic orebodies,and mainly distributes in the inner and external contact zone that between the Neoproterozoic biotite granodiorite and the Yanshanian granites.The main orebody occurs at the external contact zone,and the pegmatoid crust near the inner contact zone is an important prospecting marker of the W mineralization.Of them,the disseminated W ores within the wall rock of the Neoproterozoic biotite granodiorite is a new mineralization type identified in this paper.Combining previous geochronological and isotopic data,we propose that the mineralization of the Shimensi deposit is closely related to the intruding of the Yanshanian porphyritic biotite granite and granite porphyry.Geochemical data suggest that the biotite granodiorite is rich in Ca and had provided a large amount of Ca for the precipitation of scheelite in this area.Thus,it is a favorable wall rock type for W mineralization.The Shimensi deposit belongs to granitic-type W polymetallic deposit related to post-magmatic hydrothermal,and the ore-forming fluid was initially derived from the Yanshanian magmas.

Endodontic management of the maxillary first molar with special root canals:A case report and review of the literature

BACKGROUND As the complex anatomy of maxillary first molars is one of the major challenges in endodontic therapy,knowledge of the complicated root canal anatomy and configuration is crucial to ensure the success of endodontic treatment and prognosis.This article presents an endodontically managed left maxillary first molar with an unusual palatal root morphology.The available literature on the anatomic variation of maxillary first molars is also reviewed.CASE SUMMARY A 36-year-old man with no medical history presented to the Stomatology Department of Peking University Third Hospital complaining of a toothache during mastication in the maxillary left posterior region for approximately 3 mo.He had a spontaneous and intermittent toothache that had worsened,particularly at night.The diagnosis based on clinical examination,X-ray imaging,and cone beam computed tomography(CBCT)was symptomatic irreversible pulpitis.Nonsurgical endodontic therapy was performed for the left maxillary first molar.Five root canals revealed by CBCT included a special palatal root canal(1-2-1-shaped),two mesiobuccal root canals,and one distobuccal root canal.Evaluation of the CBCT images confirmed the root canal morphology and the clinician performed more effective cleaning,obturation,and therapy.Finally,the tooth was restored using composite resin,and the patient was satisfied with the result.CONCLUSION CBCT and a complete review of the literature may be beneficial for investigating the root canal system to achieve a biological and functional therapeutic effect.

Parity and carotid atherosclerosis in elderly Chinese women

Background The relationship between parity and atherosclerosis has been reported in some ethnic populations.However,results regarding Chinese women are still lacking.This study aimed to investigate the association of parity and carotid atherosclerosis,which has a predictive value of subsequent atherosclerotic events in elderly Chinese women.Methods A total of 2,052 participants from the medical examination center of the Third Xiangya Hospital were enrolled in the study.A standardized,structured questionnaire was administered to collect information on subjects’demographic characteristics,socioeconomic status,and cardiovascular risk factors.High-resolution ultrasound was used to examine carotid plaques and carotid intima-media thickness(IMT).Results The mean age of participants was 66.1±5.5 years.Women with more birth appeared to have a higher risk of carotid artery plaques.A multivariate-adjusted model yielded an odds ratio of 1.38(95%CI:12%-70%,P=0.003)per birth.A positive association was observed between parity and common carotid IMT(β±SE:0.029±0.006,P<0.001),and internal carotid IMT(β±SE:0.011±0.005,P=0.03)in a univariate model;however,these associations became non-significant in multivariate-adjusted models.When common carotid IMT was classified into an IMT≥1 mm group and an IMT<1 mm group,higher parity was associated with more obvious thickening both in the unadjusted model(OR=1.61,95%CI:1.29-2.00,P<0.001)and in the fully adjusted model(OR=1.43,95%CI:1.09-1.88,P=0.01).Conclusions There is a positive association between parity and risk of carotid plaques,as well as between parity and risk of obvious thickening for common carotid IMT in elderly Chinese women,indicating multiparous women might experience more atherosclerotic challenges.

Synthetic Control of Thorium Metal-Organic Frameworks for Sequencing and Sensing of Radioiodine Species

Exploring the physiochemical properties and expanding the applications of actinide-containing materials is paramount to address the escalating challenge of radioactive waste accumulation.However,unlocking the full potential of these materials is largely crippled by the radiotoxicity of the actinides.We report here two porous and luminescent thorium-based metal-organic frameworks(Th-BITD-1 and Th-BITD-2)that serve as a bifunctional platform for sequencing and sensing of radioiodine,a much more radioactive fission product discharged during the nuclear fuel reprocessing.In particular,Th-BITD-1 displays better iodine uptake performance than Th-BITD-2 via the solution-based process and vapor diffusion with the maximum adsorption capacities of 831 and 1099 mg/g,respectively.Fur thermore,Th-BITD-1 can function as a highly sensitive luminescence sensor for iodate with a quenching constant(Ksv)of 6.6(5)×10^(3) M^(-1)and a detection limit of 2.02μM,respectively,outperforming 2.96(6)×10^(3)M^(-1)and 10.5μM of Th-BITD-2.Moreover,a positive correlation between the sensing efficacy and the iodate adsorption capacity has been revealed.This work highlights the opportunity in designing novel actinide-based MOFs for their potential applications in radiological fields,e.g.,radionuclide separation and detection.

Constructing a 3D multichannel structure to enhance performance of Ni–Co–Mn hydroxide electrodes for flexible supercapacitors

The balancing of the electrochemical performance,mechanical stability,and processing technology for applying supercapacitors to flexible and wearable electronics continues to encounter severe challenges.Herein,we prepare Ni-Co-Mn hydroxide electrodes with a threedimensional multichannel structure via a simple hydrothermal method.These are constructed using vertically contiguous nano sheets with a uniform thickness and rough surface.The electrodes can provide numerous electroactive sites and accelerate the transmission of electrolyte ions.The relationship between the structure and electrochemical performances is verified by experiments and theoretical calculations.Two-dimensional(2D)planar and one-dimensional(1D)fiber electrodes are prepared using a flexible carbon cloth(CC)and carbon fiber(CF),respectively,as substrates.The assembled quasi-solid-state flexible asymmetric supercapacitor(FASC)with a twodimensional sandwich structure using NiCoMn-OH/CC as the electrode achieves a remarkable energy density of73.8 Wh·kg^(-1)at a power density of 1.03 kW·kg^(-1).The quasi-solid-state FASC with a 1D linear structure using NiCoMn-OH/CF as the electrode also attains a high energy density(12.9 Wh·kg^(-1)at a power density of0.75 W·kg^(-1)).Moreover,the electrochemical performances of the NiCoMn/CC//AC/CC and NiCoMn/CF//AC/CF FASCs are not disturbed at different bending angles(0°,45°,90°,135°and 180°),This indicates the superior flexibility of the devices.We also assemble a self-powered energy-harvesting storage system by integrating FASCs and commercial solar cells to verify its practicability.It displays sustainable development potential for energy storage.

Effect of La on the Corrosion Behavior and Mechanism of 3Ni Weathering Steel in a Simulated Marine Atmospheric Environment

The corrosion behavior and mechanism of 3Ni weathering steel in a simulated oceanic atmospheric environment are investigated in order to comprehend the impacts of La,as determined through electrochemical analysis and rust layer characterization.The results of this study demonstrate that the addition of La enhances the corrosion resistance of 3Ni weathering steel in the marine atmospheric environment,thereby reducing the corrosion rate and improving the protection of the rust layer.The influence of La on corrosion resistance can be attributed to two primary factors.Firstly,La functions as a grain refiner,minimizing the potential difference of the micro-regions on the substrate surface,thereby significantly reducing the corrosion of bare steel in the marine environment.Secondly,La inhibits the process of Fe_(3)O_(4) oxidation back toγ-FeOOH during corrosion at the local site,thus decreasing the formation ofγ-FeOOH and enhancing the charge transfer resistance.This research work may serve as a reference for expanding the application of rare earth elements in the field of weathering steel.

Metallurgy and Solidification Microstructure Control of Fusion-Based Additive Manufacturing Fabricated Metallic Alloys:A Review

The metal-based additive manufacturing(AM),also referred to as metal 3D printing,has drawn particular interest because it enables direct creation,aided by computationally-directed path design,of intricate components with site-specific compositions and geometrical requirements as well as low buy-to-fly ratios.During the last two decades,the objective of this revolutionary technology has been shifting from only“rapid prototyping”to advanced manufacturing of special high-end products or devices,which,in many aspects,outperform conventional manufacturing technologies.For fusion-based AM,significant progress has been achieved in understanding the processing window of macroscopic scales,non-equilibrium metallurgy of mesoscale scales,and grain evolution of microscopic scales.Although the versatile capacity of AM facilitates new avenues for discovering advanced materials and structures,their potential has still not been fully explored.Given the unique non-equilibrium solidification during the AM process,coarse columnar grains with strong textures are usually developed along the build direction,which downgrades the mechanical performance.To push the limits of this digital manufacturing,this review attempts to provide in-depth and comprehensive overviews of the recent progress in understanding the evolution and control of the as-built microstructure that has been made recently and the challenges encountered during the AM process.

A synthesis of the Cretaceous wildfire record related to atmospheric oxygen levels?

The Cretaceous was a significant greenhouse period in Earth's history with higher atmospheric CO_(2) levels and temperatures than today. Although evidence of combustion has been widely described from the Cretaceous deposits, our understanding of the spatiotemporal diversification pattern and process of the Cretaceous wildfires is still limited. In this study, we comprehensively synthesize a total of 271 published Cretaceous wildfire occurrences based on the by-products of burning, including fossil charcoal, pyrogenic inertinite(fossil charcoal in coal), and pyrogenic polycyclic aromatic hydrocarbons(PAHs). Spatially, the dataset shows a distinctive distribution of reported wildfire evidence characterized by high concentration in the middle latitudinal areas of the Northern Hemisphere(30°N-60°N) over the Cretaceous. Temporally, an overall increasing trend of the reported wildfire data from the Early Cretaceous to the Late Cretaceous is coincident with higher atmospheric O_(2) levels. However, the spatial and temporal patterns may result from many types of factors, such as taphonomy, preservation, and researcher biases, instead of a real picture of the Cretaceous wildfire evolution. To better understand the spatiotemporal diversification of the Cretaceous wildfire, more investigations on the record of wildfire occurrences during this period would be necessary in the future.

Single-Molecule Studies on Artificial Small-Molecule Machines

Molecular machines transduce energy from one form to another through controlled motion in response to stimuli.Despite the ubiquitous use of molecular machines in biology,understanding the detailed mechanisms of such complex structures remains challenging.Recent progress in studying the modes of operation of synthetic small-molecule machines at the single-molecule level has shed new light on the mechanisms of nano-machinery.In this mini-review,we focus on the study of artificial small-molecule machines using single-molecule techniques,including single-molecule force spectroscopy,single-molecule electrical spectroscopy,and single-molecule optical spectroscopy.We survey the techniques used to monitor single-molecule behavior to date and describe the latest studies on small-molecule machines,highlighting their common features and challenges that need to be overcome to realize the potential of these techniques in unraveling the behavior of small molecule systems.

Changes of microstructure of different quench sensitivity 7,000 aluminum alloy after end quenching

The quench sensitivity and their influential factors of 7,021, 7,085, and 7,050 alloys were investigated by the end quenching test method and the measurement of electrical conductivity, hardness, and microstructure after aging. The results indicate that 7,050 alloy has the largest changes with hardness decreasing from HV 199 to HV 167,and electrical conductivity increases from 16.6 to18.2 MS m-1when the distance from quenched end increases from 2 to 100 mm. Alloys 7,085 and 7,021 have relatively smaller changes. According to the relationship between the hardness and electrical conductivity of a supersaturated solid solution, 7,050 alloy has higher quench sensitivity than 7,085 and 7,021 alloys. The microstructure of 7,050 alloy with higher major alloy element（Zn ？ Mg ？ Cu） addition and Cu element addition is mostly affected by the changes of distance from quenched end. In 7,050 alloy, the size of intragranular precipitates is from about 10-200 nm, and the（sub） grain boundary precipitates are about 20-300 nm. Alloy 7,085 with lower Cu content is moderately affected, while 7,021 is least affected. It is found that with the increase of distance from quenched end, quenched-induced precipitate preferentially nucleates and grows in the（sub） grain boundary and then on the pre-existing Al3 Zr particles.

Intensive peatland wildfires during the Aptian-Albian oceanic anoxic event 1b:Evidence from borehole SK-2 in the Songliao Basin,NE China

The Cretaceous has been considered a“high-fire”world accompanied by widespread by-products of combustion in the rock record.The mid-Cretaceous oceanic anoxic event 1b(OAE1b)is marked by one of the major perturbations in the global carbon cycle characterized by deposition of organic-rich sediments in both marine and terrestrial settings.However,our understanding is still limited on changes in wildfire activity during OAE1b period.Here,we carried out a comprehensive analysis,including organic carbon isotope(δ^(13)C_(org)),total organic carbon(TOC),coal petrology,trace elements,and pyrolytic polycyclic aromatic hydrocarbons(pyroPAHs),of coal seams of the middle Aptian to early Albian Shahezi Formation from borehole SK-2 in Songliao Basin,Northeast China.Two negativeδ^(13)C_(org) excursions in the Shahezi Formation can be corresponded with the 113/Jacob and Kilian sub-events of OAE1b.Moreover,the intensive peatland wildfires have been identified during the sub-event periods of OAE1b based on the co-occurrence of high abundance of charcoal and pyroPAHs at that time.In addition,Sr/Ba,Sr/Cu and Sr/Rb ratios demonstrate that enhanced peatland wildfires were controlled by dryer climate conditions owing to episodic northward migration of arid zones in East Asia related with rising global temperature during the sub-events of OAE1b.The climate-driven extensive wildfire activity in the mid-latitude terrestrial ecosystems can be a contributing factor for OAE1b through the increased flux of nutrients fuelling primary producers in the lake and marine environments and leading to more speculative anoxia to allow the deposition of organic-rich sediments.Our results provide essential understanding of the importance of wildfires in driving mechanism of oceanic anoxic events(OAEs)in Earth's history.

Stability of supersaturated solid solution of quenched Al–X(X 5 Zn, Mg, Cu) binary alloys

In this study, the changing trend of crystal-lattice constant and the influential factors of the stability of supersaturated solid solutions with various alloying additions in the Al–X（Zn, Mg, Cu） binary alloys were investigated. The samples were analyzed using X-ray diffraction（XRD）,X-ray absorption fine structure（XAFS）, and scanning electron microscope（SEM）. It is found that the addition of Cu causes the largest change of crystal-lattice constant of the Al–xCu supersaturated solid solution binary alloy. The most dramatic change occurs in the initial stage of Cu addition.The change is stabilized thereafter. Also, at the same alloying element addition to the Al–X（X = Zn, Mg, Cu）binary alloys, the Al–xCu is the most unstable system.Influential factors of the stability include the lattice constant change and the type of alloying element. The larger the lattice constant changes, the more unstable the supersaturated solid solution is. The alloying element, easy to aggregate, often leads to the solid solution less stable.

Mechanical Properties of Vermicular Graphite Cast Iron Processed by Selective Laser Surface Alloying with Ultra-fine ZrO2 Ceramic Particulates

In this work, the mechanical properties and microstructures of vermicular graphite cast iron processed by selective laser surface alloying with ultra-fine ZrO2 ceramic particulates were investigated. A particulate-reinforced metal matrix composite coating with the thickness of -650 μm was fabricated by laser treatment on the sample surface. The particulates were uniformly distributed in the microstructure of the coating. The tensile strength and microhardness both increased with the particulate fraction, since more tensile load was transferred from the matrix to the reinforcement showing essential strengthening effect. The composite coating also sharply reduced the wear mass loss and thus improved the wear resistance.

Synthesis of quaternary 8-(1-acylethene-1-yl)-13-methylcoptisine chlorides and their selective growth inhibitory activity between human cancer cell lines and normal intestinal epithelial cell-6

In this paper, quaternary 8-（1-acylethene-l-yl）-13-methylcoptisine chlorides targeting thioredoxin reductases （TrxRs） were designed to test the growth inhibitory activity against human cancer cell lines and the effect on viability of the normal intestinal epithelial cell-6 （IEC-6） in vitro and to evaluate structure-activity relationship （SAR）. The introduced α, β-unsaturated ketone groups at C-8 consisting of n-alkanoyls possessing five to ten carbons or aroyls or cyclohexylcarbonyl increased the tested activity against the target cancer cell lines. By and large, this type of improvement was increasingly graced by the elongation of the aliphatic chain of the n-alkanoyls in the range of less than ten carbon atoms. The relatively more polar l-acylethene-l-yls displayed no effect on improving the activity. All the explored aroyls showed significant effect on improving the activity of the target compounds against the tested cancer cell lines with no SAR being observed, The findings of this study suggested that oil]water partition coefficient of the test compounds was one of the key factors impacting the target activity against the tested cancer cell lines. At the concentration of 10 μmol/L, except for the compounds with n-all（anoyls possessing seven or more carbons or with α-naphthoyl, none of the other compounds displayed obvious cytotoxicity on normal IEC-6 cell when co-incubated. The survival rate of IEC-6 cell ranged from 75% to 100% for the noncytotoxic compounds.