Operation optimization strategy of existing residential building energy-saving renovation market:From the perspective of subject behavior

The energy-saving renovation of existing residential buildings is a crucial measure to achieve the strategic goal of energy conservation and emission reduction in China and build ecologically livable cities.This article focuses on the perspective of subject behavior,starting from analyzing the current situation and difficulties of the operation of the energy-saving renovation market for existing residential buildings in China,drawing on the practical experience of the operation of the existing residential building energy-saving renovation market abroad.Based on principles such as systematicity,humanization,feasibility,and sustainability,the article constructs an operation optimization system of the existing residential building energy-saving renovation market from the perspective of subject behavior.In order to provide a reference for the healthy and orderly operation of the existing residential building energy-saving renovation market,this paper proposes implementation strategies for optimizing the operation of the existing residential building energy-saving renovation market.Suggestions are proposed from four aspects:optimizing the market environment,innovating the financing model,building the information sharing platform,and utilizing the synergies of the main subjects.

Generation of typical operation curves for hydrogen storage applied to the wind power fluctuation smoothing mode

In this paper,a typical-operation-curve generation method of a hydrogen energy storage system operating under the mode of stabilizing wind power fluctuations is proposed.This method is used to optimize the power and capacity configuration of the energy storage system.The time series curves of the charging and discharging powers of the hydrogen energy storage are obtained by EMD decomposition,and the curves are classified according to the similarities and differences of the characteristic parameters in different time periods.After the classification,typical charging and discharging power values of each type of curve at each moment are obtained by a cloud model,and then,typical operation curves of each type are obtained by integration.On this basis,the power and capacity of the energy storage system are optimized with the objective of economic optimization through the MATLAB CPLEX toolbox.Combined with the measured data of a wind farm with an installed capacity of 400 MW in Northeast China,the validity and rationality of the typical operation curve generation method proposed in this paper are verified.

Incentive operation characteristics and influence feedback of existing building energy-saving renovation market development

The quality of the existing building energy-saving renovation market determines the inherent inevitability of incentive,while unique requirements for the incentive should be satisfied by stage characteristics and individualization of the three entities of the existing building energy-saving renovation market development.Firstly,the analysis of internal and external factors’composition and system influencing the existing construction market development incentive structure was performed.Then,system dynamics was implemented to build the feedback model of incentive effects of market development of existing buildings energy-saving reconstruction.Discussions on the realization path of the incentive for the development of the existing energy-saving building market were also pointed out.Finally,this paper conducted the analysis of the dynamic feedback characteristics and key incentive factors of the incentive for the development of the existing building energy-saving renovation market.Based on the analyses and discussions above,this paper provides methodological guidance and implementation approach for the incentive path selection and policy-making of the existing building energy-saving transformation market,trying to help improve the incentive effectiveness of the market,and also promote healthy and sustainable development of the existing building energy-saving renovation market.

Prediction of Abdominal Visceral Obesity From Body Mass Index,Waist Circumference and Waist-hip Ratio in Chinese Adults:Receiver Operating Characteristic Curves Analysis

Objective To evaluate the sensitivity and specificity of body mass index (BMI), waist circumference (WC) and waist-to-hip ratio (WHR) measurements in diagnosing abdominal visceral obesity. Methods BMI, WC, and WHR were assessed in 690 Chinese adults (305 men and 385 women) and compared with magnetic resonance imaging (MRI) measurements of abdominal visceral adipose tissue (VA). Receiver operating characteristic (ROC) curves were generated and used to determine the threshold point for each anthropometric parameter. Results 1) MRI showed that 61.7% of overweight/obese individuals (BMI≥25 kg/m2) and 14.2% of normal weight (BMI<25 kg/m2) individuals had abdominal visceral obesity (VA≥100 cm2). 2) VA was positively correlated with each anthropometric variable, of which WC showed the highest correlation (r=0.73-0.77, P<0.001). 3) The best cut-off points for assessing abdominal visceral obesity were as followed: BMI of 26 kg/m2, WC of 90 cm, and WHR of 0.93, with WC being the most sensitive and specific factor. 4) Among subjects with BMI≥28 kg/m2 or WC≥95 cm, 95% of men and 90% of women appeared to have abdominal visceral obesity. Conclusion Measurements of BMI, WC, and WHR can be used in the prediction of abdominal visceral obesity, of which WC was the one with better accuracy.

Application of artificial neural networks for operating speed prediction at horizontal curves: a case study in Egypt

Horizontal alignment greatly affects the speedof vehicles at rural roads. Therefore, it is necessary toanalyze and predict vehicles speed on curve sections.Numerous studies took rural two-lane as research subjectsand provided models for predicting operating speeds.However, less attention has been paid to multi-lane highwaysespecially in Egypt. In this research, field operatingspeed data of both cars and trucks on 78 curve sections offour multi-lane highways is collected. With the data, correlationbetween operating speed （V85） and alignment isanalyzed. The paper includes two separate relevant analyses.The first analysis uses the regression models toinvestigate the relationships between V85 as dependentvariable, and horizontal alignment and roadway factors asindependent variables. This analysis proposes two predictingmodels for cars and trucks. The second analysisuses the artificial neural networks （ANNs） to explore theprevious relationships. It is found that the ANN modelinggives the best prediction model. The most influential variableon V85 for cars is the radius of curve. Also, for V85 fortrucks, the most influential variable is the median width.Finally, the derived models have statistics within theacceptable regions and they are conceptually reasonable.

Braking distance prediction for vehicle consist in low-speed on-sight operation:a Monte Carlo approach

The first and last mile of a railway journey, in both freight and transit applications, constitutes a high effort and is either non-productive(e.g. in the case of depot operations) or highly inefficient(e.g. in industrial railways). These parts are typically managed on-sight, i.e. with no signalling and train protection systems ensuring the freedom of movement. This is possible due to the rather short braking distances of individual vehicles and shunting consists. The present article analyses the braking behaviour of such shunting units. For this purpose, a dedicated model is developed. It is calibrated on published results of brake tests and validated against a high-definition model for lowspeed applications. Based on this model, multiple simulations are executed to obtain a Monte Carlo simulation of the resulting braking distances. Based on the distribution properties and established safety levels, the risk of exceeding certain braking distances is evaluated and maximum braking distances are derived. Together with certain parameters of the system, these can serve in the design and safety assessment of driver assistance systems and automation of these processes.

Determining endemic values of cutaneous leishmaniasis in Iranian Fars province by retrospectively detected clusters and receiver operating characteristic curve analysis

Objective: To determine the endemic values of cutaneous leishmaniasis in different cities of Fars province, Iran. Methods: Totally, 29 201 cases registered from 2010 to 2015 in Iranian Fars province were selected, and the endemic values of cutaneous leishmaniasis were determined by retrospective clusters derived from spatiotemporal permutation modeling on a time-series design. The accuracy of the values was assessed using receiver operating characteristic(ROC) curve. SPSS version 22, Arc GIS, and ITSM 2002 software tools were used for analysis. Results: Nine statistically significant retrospective clusters(P<0.05) resulted in finding seven significant and accurate endemic values(P<0.1). These valid endemic scores were generalized to the other 18 cities based on 6 different climates in the province. Conclusions: Retrospectively detected clusters with the help of ROC curve analysis could help determine cutaneous leishmaniasis endemic values which are essential for future prediction and prevention policies in the area.

WEAK TYPE ESTIMATES FOR THE MAXIMAL OPERATORS ASSOCIATED TO PLANE CURVES

For the plane curves Γ,the maximal operator associated to it is defined by Mf(x)=sup|∫f(x-Γ(t))(r^(-1)t)r^(-1)dt| where is a Schwartz function.For a certain class of curves in R^2,M is shown to bounded on (H(R^2),Weak L^1(R^2).This extends the theorem of Stein & Wainger and the theo- rem of Weinberg.

基于Curvelet变换的肺结节CT图像良恶性分类研究

目的早期肺癌患者的CT图像表现为结节状(在肺野内直径≤3cm的病灶),需要与结核球等良性病变鉴别开,以提高患者的5年生存率。方法本文基于Curvelet变换提取能量、熵、灰度均值及灰度标准差四种纹理特征值,按7∶3比例将样本分为训练集与验证集。使用BP(back propagation)神经网络作为分类器。每一种纹理参数测试集的神经网络仿真值结合病理诊断结果绘制受试者工作特征曲线(receiver operator characteristic curve,ROC曲线),根据ROC下面积得到最优的几种纹理参数用于良恶性分类,并将分类结果与病理诊断结果进行比较。结果四种纹理参数构建的BP网络均具有诊断价值,每种纹理参数诊断价值各不相同,其中熵与灰度标准差的诊断价值优于能量与灰度均值,并且通过组合多种纹理参数可以提高诊断准确性。结论使用熵与灰度标准差两种纹理特征值构建BP神经网络能达到最好的分类效果,在一定程度上有利于肺癌的早期诊断。

Comparative study of CEA and CA19-9 in esophageal,gastric and colon cancers individually and in combination(ROC curve analysis)

Objective： To determine the clinical serum levels of carcinoembryonic antigen （CEA） and carbohydrate antigen 19-9 （CA19-9）, individually and in combination, for the diagnosis of 50 healthy subjects and 150 cases of esophageal, gastric, and colon cancers. Methods： The sensitivities of the two markers were compared individually and in combination, with specificity set at 100%. Receiver operating characteristic （ROC） curves were plotted. Results： Serum CEA levels were significantly higher in cancer patients than in the control group. The sensitivity of CEA was determined： in esophageal cancer, sensitivity=28%, negative predictive value （NPV）=61.72%, and AUC=0.742 （SE=0.05）, with a significance level of P〈0.0001; in gastric cancer, sensitivity=30%, NPV=58.82%, and AUC=0.734 （SE=0.0S）, with a significance level of P〈0.0001; in colon cancer, sensitivity=74%, NPV=79.36%, and AUC=0.856 （SE=0.04）, with a significance level of P〈0.0001. The sensitivity of CA19-9 was also evaluated： in esophageal cancer, sensitivity=18%, NPV=54.94%, and AUC=0.573 （SE=0.05）, with a significance level of P=0.2054. In gastric cancer, sensitivity=42%, NPV=63.29%, and AUC=0.679 （SE=0.05）, with a significance level of P〈0.0011. In colon cancer, sensitivity=26%, NPV=57.47%, and AUC=0.S80 （SE=0.05）, with a significance level ofP=0.1670. The following were the sensitivities of CEA/CA19-9 combined： in esophageal cancer, sensitivity=42%, NPV=63.29%, SE=0.078 （95% CI： 0.0159-0.322）; gastric cancer, sensitivity=S8%, NPV=70.42%, SE=0.072 （9$% CI： -0.0866-0.198）; and colon cancer, sensitivity=72%, NPV=78.12%, SE=0.070 （9S% CI： 0.137-0.415）. Conclusion： CEA exhibited the highest sensitivity for colon cancer, and CA19-9 exhibited the highest sensitivity for gastric cancer. Combined analysis indicated an increase in diagnostic sensitivity in esophageal and gastric cancer compared with that in colon cancer.

Operational Safety Assessment of a High-Speed Train Exposed to the Strong Gust Wind

The operational safety characteristics of trains exposed to a strong wind have caused great concern in recent years.In the present paper,the effect of the strong gust wind on a high-speed train is investigated.A typical gust wind model for any wind angle,named“Chinese hat gust wind model”,was first constructed,and an algorithm for computing the aerodynamic loads was elaborated accordingly.A vehicle system dynamic model was then set up in order to investigate the vehicle system dynamic characteristics.The assessment of the operational safety has been conducted by means of characteristic wind curves(CWC).As some of the parameters of the wind-train system were difficult to measure,we also investigated the impact of the uncertain system parameters on the CWC.Results indicate that,the descending order of the operational safety index of the vehicle for each wind angle is 90°-60°-120°-30°-150°,and the worst condition for the operational safety occurs when the wind angle reaches around 90°.According to our findings,the gust factor and aerodynamic side force coefficient have great impact on the critical wind speed.Thus,these two parameters require special attention when considering the operational safety of a railway vehicle subjected to strong gust wind.

Learning curves of robot-assisted pedicle screw fixations based on the cumulative sum test

BACKGROUND In robot-assisted(RA)spine surgery,the relationship between the surgical outcome and the learning curve remains to be evaluated.AIM To analyze the learning curve of RA pedicle screw fixation(PSF)through fitting the operation time curve based on the cumulative summation method.METHODS RA PSFs that were initially completed by two surgeons at the Beijing Jishuitan Hospital from July 2016 to March 2019 were analyzed retrospectively.Based on the cumulative sum of the operation time,the learning curves of the two surgeons were drawn and fit to polynomial curves.The learning curve was divided into the early and late stages according to the shape of the fitted curve.The operation time and screw accuracy were compared between the stages.RESULTS The turning point of the learning curves from Surgeons A and B appeared in the 18th and 17th cases,respectively.The operation time[150(128,188)min vs 120(105,150)min,P=0.002]and the screw accuracy(87.50%vs 96.30%,P=0.026)of RA surgeries performed by Surgeon A were significantly improved after he completed 18 cases.In the case of Surgeon B,the operation time(177.35±28.18 min vs 150.00±34.64 min,P=0.024)was significantly reduced,and the screw accuracy(91.18%vs 96.15%,P=0.475)was slightly improved after the surgeon completed 17 RA surgeries.CONCLUSION After completing 17 to 18 cases of RA PSFs,surgeons can pass the learning phase of RA technology.The operation time is reduced afterward,and the screw accuracy shows a trend of improvement.

Optimal Weights in Nonparametric Analysis of Clustered ROC Curve Data

In diagnostic trials, clustered data are obtained when several subunits of the same patient are observed. Within-cluster correlations need to be taken into account when analyzing such clustered data. A nonparametric method has been proposed by Obuchowski (1997) to estimate the Receiver Operating Characteristic curve area (AUC) for such clustered data. However, Obuchowski’s estimator gives equal weight to all pairwise rankings within and between cluster. In this paper, we modify Obuchowski’s estimate by allowing weights for the pairwise rankings vary across clusters. We consider the optimal weights for estimating one AUC as well as two AUCs’ difference. Our results in this paper show that the optimal weights depends on not only the within-patient correlation but also the proportion of patients that have both unaffected and affected units. More importantly, we show that the loss of efficiency using equal weight instead of our optimal weights can be severe when there is a large within-cluster correlation and the proportion of patients that have both unaffected and affected units is small.

基于新生儿、孕妇临床特征构建新生儿呼吸窘迫综合征的预测模型

目的基于新生儿、孕妇临床特征构建新生儿呼吸窘迫综合征(NRDS)的预测模型。方法选取2020年1月—2023年1月收治的102例NRDS患儿纳入NRDS组,另择同期健康新生儿150例纳入无NRDS组,回顾性收集临床资料。分析2组新生儿情况、孕妇情况,采用多因素Logistic回归分析NRDS发生的危险因素,建立预测模型,并绘制受试者工作特征(ROC)曲线分析预测模型对NRDS的预测价值。结果与无NRDS组比较,NRDS组胎龄<34周、出生体质量<2 kg、分娩方式为剖宫产、胎儿窘迫、胎膜早破、酸中毒比例高(P<0.05,P<0.01)。与无NRDS组比较,NRDS组孕妇年龄≥35岁、初产、妊娠期高血压疾病、妊娠期糖尿病、合并生殖道感染、产前检查低于9次比例高,血清25-羟基维生素D(25-OH-D)水平低(P<0.05,P<0.01)。胎龄<34周、出生体质量<2 kg、分娩方式为剖宫产、胎儿窘迫,以及孕妇年龄≥35岁、妊娠期糖尿病、产前检查低于9次为NRDS发生的独立危险因素(P<0.05,P<0.01);孕妇血清25-OH-D水平升高为其保护因素(P<0.01)。根据上述结果构建预测模型,并绘制ROC曲线,结果显示,当Logit(P)>18.570时,预测NRDS发生的曲线下面积为0.893,诊断敏感度为81.37%、特异度为82.00%。结论胎龄<34周、出生体质量<2 kg、分娩方式为剖宫产、胎儿窘迫,以及孕妇年龄≥35岁、妊娠期糖尿病、产前检查低于9次为NRDS的独立危险因素,孕妇血清25-OH-D水平升高为其保护因素,据此构建预测模型对NRDS预测价值较高,可为筛选高危患儿、制订临床干预策略提供依据。

新疆高校新生身体形态指标和血压的特征及关联性研究

目的了解新疆高校新生身体形态指标与血压的特征及差异性,分析其关联性,为新疆高校新生高血压防治和干预提供参考依据。方法采用随机抽样对新疆4所高校的1853名18~21岁大学新生进行身体形态、腰围、臀围、血压等指标测量,根据受试者血压分为正常血压组和血压偏高组,分析不同性别、民族、年龄段新生血压的差异;统计学方法采用χ^(2)检验、Pearson相关性分析、Logistic回归分析及受试者操作特征(receiver operating characteristic,ROC)曲线分析。结果女生的体脂率(percent body fat,PBF)和体脂量高于男生[(24±8)%与(18±7)%,t=-17.95,P<0.01);(18±7)kg与(14±7)kg,t=-4.27,P<0.01],其他指标均低于男生;除体脂率外,汉族学生的身体形态指标均高于少数民族(P值均<0.01)。男生的血压偏高检出率高于女生[51.5%(538/1044)与42.4%(343/809),χ^(2)=15.250,P<0.01];汉族血压偏高检出率高于少数民族[59.4%(372/626)与41.5%(509/1227),χ^(2)=53.503,P<0.01];18~19岁新生的血压偏高检出率高于20~21岁[(51.4%(348/677)与45.3%(533/1176),χ^(2)=6.369,P<0.05)]。不同性别血压偏高组的身体形态指标均>正常血压组;大学新生收缩压与舒张压与身体形态呈现不同程度的相关性,多因素Logistics回归分析结果显示,男生的身体质量指数(body mass index,BMI)、PBF、体脂量、内脏脂肪等级(visceral fat level,VFL)、腰臀比(waist to hip ratio,WHR)和女生的体质量、BMI、体脂量、VFL超标以及女生体表面积(body surface area,BSA)下降都会增加血压偏高的风险;不同身体形态指标对血压偏高的曲线下面积(area under the curve,AUC)均>0.5,且男生的每项指标AUC均大于女生,其中男生身体形态中有多项指标与血压偏高的AUC>0.65。结论身体形态指标对男生血压偏高的诊断意义大于女生,尤其是PBF指标,全身性肥胖,特别是皮下脂肪肥胖与血压的相关性较高。

动态增强磁共振成像定量参数联合表观扩散系数值对外周带前列腺癌的诊断价值研究

目的探究动态增强磁共振成像(DCE-MRI)定量参数联合表观扩散系数(ADC)值诊断外周带早期前列腺癌的价值。方法选取2019年2月至2021年12月经穿刺病理学检查确诊为外周带早期前列腺癌31例和前列腺炎27例为研究对象。患者均进行DCE-MRI定量参数检查,以病理学检查结果为金标准,分析不同患者的DCE-MRI特征。并采用受试者工作特征曲线下面积(AUC)分析基于DCE-MRI定量参数与扩散加权成像(DWI)序列对外周带早期前列腺癌与前列腺炎的诊断价值。结果31例前列腺癌患者中,T2加权成像(T2WI)以外周带结节状低信号为主,占58.06%;DWI以结节状、弥漫性高信号,ADC值下降为主,占51.61%;DCE-MRI可见病灶早期强化,以延迟后病灶造影剂退出,强化曲线呈流出型为主,占64.52%。27例前列腺炎患者中,T2WI以外周带单侧或双侧弥漫性不均匀低信号为主,占51.85%;DWI可见外周带单侧或双侧不规则高信号,ADC值降低为主,占59.26%;DCE-MRI可见病灶早期强化,以延迟后造影剂退出不明显,强化曲线呈流入型为主,占81.48%。外周带早期前列腺癌患者ADC值低于前列腺炎,速率常数(Kep)值、转移常数(K^(trans))高于前列腺炎(P<0.05)。DCE-MRI定量参数联合ADC值诊断外周带早期前列腺癌的AUC为0.862(95%CI:0.659,0.865)、敏感度为87.10%,特异度为81.48%,准确度为84.48%,阳性预测值为84.38%,阴性预测值为84.62%。结论DCE-MRI定量参数联合ADC值对外周带早期前列腺癌的诊断效能良好,能显著提高临床检出率,为疾病的诊断与治疗提供依据。

压裂施工曲线应用于深层页岩气水平井裂缝评价

页岩气水平井通常没有取芯、电成像等资料,增加了裂缝识别难度,而压裂施工曲线能较好地反映出压裂效果和压前天然裂缝的发育情况。以川南泸州Y101区块深层页岩气地层为例,根据携砂液阶段压裂施工曲线类型及特征刻度水平井压前裂缝层段、基质层段的测井响应特征,利用小波变换提取反映裂缝信息的高频微弱信号建立小波变换综合系数(W_(I))、交会图优选6项对裂缝响应敏感的参数指标、层次分析法与模糊数学法构建裂缝评价综合系数(F_(I)),并进一步结合不同压裂施工曲线类型与测井信息的关系,实现了水平井裂缝层段识别及发育级别评价。研究结果表明,携砂液阶段压裂施工曲线形态有下降型(Ⅰ)、下降稳定型(Ⅱ)、稳定型(Ⅲ)及上升型(Ⅳ)4种类型,其中,当自然伽马高值、补偿中子和密度明显增大、声波时差增大伴“锯齿状”周波跳跃、双侧向呈“正差异”且W_(I)>0.18,F_(I)>0.430时,压裂施工曲线为下降型,裂缝发育好(F-A级);0.3906F_(I)<0.430时,既有下降型又有下降稳定型,裂缝较发育(F-B级);0.3506F_(I)<0.390时,为下降稳定型,裂缝一般发育(F-C级)。

卡托普利抑制试验在原发性醛固酮增多症诊断和分型以及临床转归中的应用

背景 原发性醛固酮增多症(PA)作为继发性高血压中发病率最高、心脑血管危害大但手术后治愈率高的疾病,已被各大高血压指南推荐扩大筛查、早期诊断和治疗。但该类患者的确诊、分型和治疗后临床转归判定方式繁多且存在较多争议。卡托普利抑制试验(CCT)因其便捷、安全可直接用于社区、门诊,期望CCT能对PA患者进行全程管理以改善预后。目的 探究CCT对PA的诊断、分型以及临床转归的判断能力。方法 选取2020-10-01—2022-12-30在四川大学华西医院内分泌代谢科接受内分泌性高血压病因筛查并登记的824例患者为研究对象。经筛选后最终370例患者纳入研究,其中123例原发性高血压(EH)患者纳入EH组,247例PA患者分别纳入单侧醛固酮瘤(APA)组81例、特发性醛固酮增多症(IHA)组55例和未分型PA(u-PA)组111例。比较4组间差异并绘制CCT后各指标及联合诊断PA的受试者工作特征(ROC)曲线,确定最佳截断值。其次绘制CCT后各指标诊断APA和IHA亚型的ROC曲线,计算ROC曲线下面积(AUC)评估CCT对APA和IHA的分型判断能力。最后根据术后临床结局将单侧肾上腺切除患者分为3组:未缓解组11例、临床改善组27例和临床缓解组54例,比较3组间差异并判断CCT对APA患者术后临床转归的判断能力。结果 CCT后血浆醛固酮浓度(PAC)对PA的诊断效能最高(AUC=0.921,95%CI=0.893~0.950),最佳截断值为11.7 ng/dL,灵敏度、特异度分别为84.6%和86.0%;CCT后醛固酮/肾素比值(ARR)对PA也有较好的诊断效能(AUC=0.868,95%CI=0.823~0.923),最佳截断值为2.8(ng/dL)/(mU/L),灵敏度、特异度分别为82.2%和81.0%。CCT后PAC>17.0 ng/dL可协助诊断APA亚型,CCT后PAC<11.7 ng/dL同时ARR<2.8(ng/dL)/(mU/L)的患者可排除APA亚型。在接受手术治疗的患者中,有87.2%患者经CCT后PAC<11.7 ng/dL,89.7%患者CCT后ARR<2.8(ng/dL)/(mU/L)均接近术后临床缓解水平(88.0%)。结论 CCT可全程用于PA患者的诊断、分型和临床转归评价,CCT后PAC及CCT后ARR诊断PA的最佳截断值分别为11.7 ng/dL和2.8(ng/dL)/(mU/L),也可用于APA的分型判断以及术后生化缓解的判断。CCT前采血检验临床意义小,可适当简化流程。

肾小管及肾小球标志物在2型糖尿病患者不同肾损伤阶段诊断价值的研究

目的探讨肾小管及肾小球相关标志物在2型糖尿病(type 2 diabetes mellitus,T2DM)患者不同肾损伤阶段的诊断价值。方法选取于2018年4月1日至2019年10月31日入住首都医科大学附属北京同仁医院内分泌科的T2DM患者272例,完善临床生化指标及尿蛋白四项:尿微量白蛋白/肌酐(urinary albumin to creatinine ratio,ACR)、α1-微球蛋白/肌酐(urinary α1-microglobulin to creatinine ratio,UA1CR)、免疫球蛋白G/肌酐(urinary immunoglobulin G to creatinine ratio,UIGG)、转铁蛋白/肌酐(urinary transferrin to creatinine ratio,UTRF);进行眼底照相、核医学99mTc-EC检测肾有效血浆流量(effective renal plasma flow,ERPF)和99mTc-DTPA检测肾小球滤过率(glomerular filtration rate,GFR)。根据ACR和眼底检查结果分为4组:正常蛋白尿无糖尿病视网膜病变(diabetic retinopathy,DR)132例,即对照组(ACR≤30 mg/g);正常蛋白尿合并DR 32例,为糖尿病肾病(diabetic kidney disease,DKD)前期组;微量蛋白尿组78例(30<ACR≤300 mg/g)和大量蛋白尿组30例(ACR>300 mg/g)。比较四组间尿蛋白四项和ERPF、GFR的水平,通过受试者工作特征(receiver operating characteristic,ROC)曲线评价上述各指标在不同肾损伤阶段的诊断价值。结果尿蛋白四项和ERPF、GFR的水平在不同组间差异有统计学意义(P<0.05)。在尿蛋白正常组中,DR组中肾小管功能标志物UA1CR较对照组明显升高(P<0.01);肾小球功能标志物ACR、UTRF和GFR在两组间差异无统计学意义(P>0.05),DR组UIGG较对照组升高(P<0.01)。在微量蛋白尿组和大量蛋白尿组,尿蛋白四项随肾损伤程度增加而增加,而ERPF和GFR随肾损伤程度增加而降低。ROC曲线分析显示,在尿蛋白排出正常的T2DM患者中合并DR组中肾小管功能标志物UA1CR和ERPF的曲线下面积(area under the curve,AUC)分别为68.2%(P<0.01)和60.5%(P<0.05),而肾小球功能标志物ACR和GFR的AUC均小于60%,差异无统计学意义(P>0.05)。尿蛋白四项及GFR在微量和大量蛋白尿组的AUC均大于60%(P<0.05),ERPF在大量蛋白尿组AUC为67.2%(P<0.05)。结论T2DM极早期微血管改变即ACR正常仅有DR时,肾小管标志物UA1CR先于肾小球标志物ACR和GFR发生变化。肾损伤早期,肾小管标志物诊断效能优于肾小球;肾损伤后期,肾小球标志物诊断效能优于肾小管。提示DKD肾小管功能的改变可能早于肾小球。

颅脑创伤患者早期并发心脏收缩功能不全存在较多影响因素

目的:研究颅脑创伤患者早期并发心脏收缩功能不全相关因素。方法:收集123例单纯性颅脑创伤(iTBI)患者的临床资料,均行超声心动图检测,根据检测结果将患者分为心脏收缩功能正常组(100例)及心脏收缩功能不全组(23例)。比较2组患者的临床资料,采用Logistic回归分析影响患者并发心脏收缩功能不全的相关因素,绘制受试者工作特征(ROC)曲线评估各指标对iTBI患者并发心功能不全的预测价值。结果:与心脏收缩功能正常组比较,心脏收缩功能不全组入院时格拉斯哥昏迷(GCS)评分更低;而入院时心率、收缩压及血清hs-cTnT水平更高(P均<0.05)。多因素Logistic回归分析显示,入院时心率、GCS评分、血清hs-cTnT是iTBI患者并发心脏收缩功能不全的影响因素(P均<0.05)。经ROC曲线分析入院时血清hs-cTnT水平预测iTBI患者并发心脏收缩功能不全的曲线下面积、灵敏度、特异性及约登指数高于入院时心率和GCS评分预测(P均<0.05)。结论:iTBI患者早期并发心脏收缩功能不全相关因素包括入院时心率、GCS评分、血清hs-cTnT水平,其中入院时血清hs-cTnT水平预测iTBI患者早期并发心脏收缩功能不全的效能较高。