以胶原蛋白为基质的肠内营养制剂应用效果多中心临床研究

目的通过多中心随机对照的临床试验研究,比较以胶原蛋白为基质的新型肠内营养制剂与标准型肠内营养制剂对患者营养状况的影响,以了解新型肠内营养制剂的临床应用效果。方法本研究共6家医疗单位共同参与,共收集91例,分为对照组（标准肠内营养）及干预组（以胶原蛋白为基质的肠内营养）,管饲补充104.6~125.5kJ（25~30kcal）/（kg·d）,共7d,检测研究开始前后患者体格指标、营养相关指标、安全性指标等。结果组内比较显示两组患者在管饲两种不同的肠内营养制剂后营养风险筛查评分（NRS2002）较管饲前均有所降低（均P＜0.025）;组间差值比较显示患者营养状况、营养风险筛查（NRS2002）评分、胃肠道不良反应在两组间均无统计学差异（均P＞0.025）。结论以胶原蛋白为基础经氨基酸模式优化后的肠内营养制剂与标准型肠内营养制剂均可以有效改善患者的营养状况,有助于促进患者的疾病预后。     

早期肠内营养在胃癌根治术后的应用分析

目的 探讨术后早期肠内营养（EN）在胃癌患者中应用的安全性和可行性。方法 将78 例接受胃癌根治术的患者 随机分为两组,其中EN 组40 例,全肠外营养（TPN）组38例。比较两组患者营养状况变化、肠功能恢复情况、术后并发症发生情况、营养费用和住院时间等。结果 术后第7天,EN 组患者总淋巴细胞计数（TLC）为（1.74±0.25）×109/L,明显高于TPN 组的TLC（1.59±0.28）×109/L（P＜0.05）,其他营养指标两组间比较均无统计学差异（均P＞0.05）;EN 组患者肠功能恢复较TPN 组快,营养费用和住院时间较TPN 组少,均有统计学差异（均P＜0.05）;EN 组与TPN 组术后并发症的发生率分别为12.50%和18.42%,比较无统计学差异（P＞0.05）。结论 术后早期EN 可促进肠道功能的恢复,有效改善患者营养状态,降低住院费用。     

考虑患者止步行为的动态入院接收决策模型

大型公立医院病床供需矛盾日益突出,医院作为服务系统有必要考虑由于病床需求响应速度不及时而引起的患者策略性行为。针对患者到达时间的随机性与住院时长的不确定性,本文提出考虑患者止步行为的动态入院接收决策问题,制定了适用于可等待慢性病患者的入院接收决策方法,旨在提高患者的就医满意度,有效权衡多类患者的接收数量,降低由于科室响应速度过慢引发的患者止步频率。首先,本文对考虑患者止步行为的动态入院接收决策问题进行数学描述及符号定义;然后,对患者止步行为的影响因素进行分析并构建止步概率函数;进一步地,构建考虑患者止步行为的动态入院接收马尔可夫决策过程(MDP)模型,并针对模型特点设计值迭代算法,最后通过数值算例验证本文所提方法的可行性与有效性。     

完全腹腔镜胰十二指肠切除术6例临床疗效分析

目的 评估完全腹腔镜胰十二指肠切除术（laparoscopic pancreaticoduodenectomy,LPD）的可行性、安全性。方 法 采用LPD 治疗胰头或十二指肠肿瘤患者6 例,回顾性分析手术时间、术中出血量、淋巴结清扫数目、术后肛门排气时间、术后住院天数、手术并发症发生率及术后短期疗效。结果 6 例手术均在完全腹腔镜下完成,无中转开腹病例。手术时间（380.5±38.1）min;出血量（241.7±189.3）ml;清扫淋巴结（15.3±2.8）枚;平均肛门排气时间（3.5±1.0）d;术后住院（14.0±5.7）d。手术并发症发生率为33.3％（2/6）,其中轻度胰漏1例,肺炎1例;本组患者术后随访3~12个月,无肿瘤复发及转移。结论 LPD 安全、可行,能达到胰头或十二指肠肿瘤根治性切除的目的。     

替罗非班在老年STEMI患者PCI治疗中的作用

目的 观察小剂量替罗非班在老年急性ST段抬高型心肌梗死(STEMI)急诊经皮冠状动脉介入（PCI）术中的治疗效果, 并探讨其临床安全性。方法 选取急性STEMI并行急诊PCI治疗的老年患者150 例,使用随机数字表法分为替罗非班组（80 例）和对照组（70例）,两组患者术前均予以阿司匹林300mg 及氯吡格雷300mg顿服,术后长期服用阿司匹林100mg、氯吡格雷75mg,1 次/d,替罗非班组在常规治疗基础上给予替罗非班负荷量（5μg/kg）在3min内静脉推注后以0.075μg/（kg·min）静脉滴注维持24h。观察两组手术前后梗死相关动脉TIMI血流情况、术后心电图相关导联抬高的ST 段回落幅度、住院期间出血及继发血小板减少症等事件发生率、术后3个月左心室射血分数（LVEF）及主要不良心血管事件（MACE）发生情况。结果 PCI术后,替罗非班组TIMI 血流2～3 级者75例（93.75%）,ST 段回落幅度为（69.96±15.53）%,均显著高于对照组的58 例（82.86%）和（64.18±14.02）%,差异均有统计学意义（均P＜0.05）;住院期间替罗非班组出血事件发生6例（7.5%）,低于对照组（P＜0.05）,而血小板减少情况未见明显增多（P＞0.05）。3个月随访结果显示,替罗非班组LVEF改善情况显著优于对照组（P＜0.01）,而MACE 发生率则降低（P＜0.05）。结论 小剂量替罗非班能有效提高老年急性STEMI患者PCI术后冠状动脉血流灌注,且不增加出血及血小板减少的风险,同时可改善心功能、降低MACE的发生。     

带蒂脾段后腹膜固定术在门静脉高压症外科治疗中的应用

目的：评价带蒂脾段后腹膜固定术治疗门静脉高压症的临床应用可行性及疗效。方法选择肝炎后肝硬化、门静脉高压症、脾功能亢进患者44例,其中行带蒂脾段后腹膜固定术24例（观察组）,行全脾切除术20例（对照组）。比较两组患者手术时间、术中出血量、术后住院时间及术后并发症发生情况,以及周围血象（白细胞计数、血小板计数）、免疫功能指标（CD4、CD8、CD4/CD8）等。结果观察组手术时间明显短于对照组、术后并发症发生率明显低于对照组（均P＜0.05）;观察组术后10d、术后2个月白细胞计数均明显低于对照组（均P＜0.05）,术后3、10d及术后2个月血小板计数均明显低于对照组（均P＜0.05）;观察组术后10d CD4比例及IgG含量均明显高于对照组（均P＜0.05）,术后2个月CD4比例、CD4/CD8及IgA、IgM含量均明显高于对照组（均P＜0.05）,CD8比例明显低于对照组（P＜0.05）。结论带蒂脾段后腹膜固定手术是一种较好的保脾手术方式,保留了脾脏的部分或大部分功能,避免了术后门静脉血栓的发生,并且远期具有分流作用,技术上是安全可行的。     

温州地区维持性血液透析患者矿物质代谢紊乱情况调查

目的 了解温州地区维持性血液透析患者矿物质代谢紊乱情况及相关影响因素。方法 收集2013 年在温州地区长期维持性血液透析患者血钙、血磷、全段甲状旁腺激素（iPTH）的资料,并根据美国肾脏病协会指南（KDOQI）及中华医学会肾脏病学分会（CSN）制订的《慢性肾脏病矿物质和骨异常诊治指导》计算患者的血钙、血磷、iPTH 的达标率,并对相关影响因素进行分析。结果 共收集2 227 例2013 年在温州地区各家透析中心维持性血液透析患者的资料。按KDOQI 指南标准,患者血钙、血磷、iPTH 的达标率分别为44.90%、46.30%、27.64%,3 项均达标者占6.29%;按《慢性肾脏病矿物质和骨异常诊治指导》建议,患者血钙、血磷、iPTH 的达标率分别为57.66%、46.30%、61.14%,3 项均达标者占16.97%。此外,三级医院维持性血液透析患者的平均血磷水平为（1.67±0.51）mmol/L,血磷达标率49.10%,二级医院患者的平均血磷水平为（1.79±0.53）mmol/L,达标率为43.22%,三级医院维持性血液透析患者的血磷达标率情况优于二级医院。血白蛋白、含钙磷结合剂的使用及透析频率是影响血钙达标的独立相关因素。患者的性别、年龄、活性维生素D 的使用、透析龄及透析频率是影响血磷达标的独立相关因素。患者活性维生素D的使用是影响iPTH 达标的独立相关因素。结论 温州地区维持性血液透析患者矿物质代谢紊乱纠正情况与有关指南的要求仍然存在较大差距;患者性别、营养状态、透析频率、含钙磷结合剂的服用、活性维生素D 的使用等是影响维持性血液透析患者矿物质代谢紊乱纠正的主要相关因素。     

Coronary Risk Prediction by Logical Analysis of Data

The objective of this study was to distinguish within a population of patients with known or suspected coronary artery disease groups at high and at low mortality rates. The study was based on Cleveland Clinic Foundation's dataset of 9454 patients, of whom 312 died during an observation period of 9 years. The Logical Analysis of Data method was adapted to handle the disproportioned size of the two groups of patients, and the inseparable character of this dataset – characteristic to many medical problems. As a result of the study, we have identified a high-risk group of patients representing 1/5 of the population, with a mortality rate 4 times higher than the average, and including 3/4 of the patients who died. The low-risk group identified in the study, representing approximately 4/5 of the population, had a mortality rate 3 times lower than the average. A Prognostic Index derived from the LAD model is shown to have a 83.95% correlation with the mortality rate of patients. The classification given by the Prognostic Index was also shown to agree in 3 out of 4 cases with that of the Cox Score, widely used by cardiologists, and to outperform it slightly, but consistently. An example of a highly reliable risk stratification system using both indicators is provided.     

基于MDP和动态规划的医疗检查预约调度优化方法研究

医疗检查对医生诊断病人病情具有重要作用。针对医疗检查资源的预约调度问题,考虑两台设备、三类病人且各类病人所需检查时间不同的情况。以医院在检查设备方面收益最大化为目标,建立有限时域马尔可夫决策(Markov decision process,MDP)模型,并结合动态规划理论,得出系统最优的预约排程策略。通过matlab仿真模拟医院的检查预约情况,并结合调研数据,实例验证了该预约策略相对于传统预约策略的优越性。最后,对设备的最大可用时间和住院病人的预约请求到达率模型进行敏感性分析,研究了预约策略的适用性。     

Networth exposure to interest rate risk: An empirical analysis of Indian commercial banks

In the Basel II era, management of interest rate risk in the banking book has become significant. In the first study of its kind, we develop a simulation based driver-driven approach to estimate the impact of interest rate volatility on the networth of Indian banks during the period 2002–2004. We derive the interest rates that drive changes in deposit and prime lending rates (PLR). Then we perform Monte Carlo simulation and multiple regressions, on these driver rates, to obtain simulated shocks to deposit rates and PLR. We use these simulated shocks to get the 99% worst EVE loss for the sample banks. These losses are much larger than what the existing literature suggests. This is because, apart from repricing risk, we are the first to find evidence of significant basis risk. Our results have important policy implications both for banks and regulators.     

On the regulator–insurer interaction in a structural model

In this paper, we provide a new insight to the previous work of Briys and de Varenne [E. Briys, F. de Varenne, Life insurance in a contingent claim framework: Pricing and regulatory implications, Geneva Papers on Risk and Insurance Theory 19 (1) (1994) 53–72], Grosen and Jørgensen [A. Grosen, P.L. Jørgensen, Life insurance liabilities at market value: An analysis of insolvency risk, bonus policy, and regulatory intervention rules in a barrier option framework, Journal of Risk and Insurance 69 (1) (2002) 63–91] and Chen and Suchanecki [A. Chen, M. Suchanecki, Default risk, bankruptcy procedures and the market value of life insurance liabilities, Insurance: Mathematics and Economics 40 (2007) 231–255]. We show that the particular risk management strategy followed by the insurance company can significantly change the risk exposure of the company, and that it should thus be taken into account by regulators. We first study how the regulator establishes regulation intervention levels in order to control for instance the default probability of the insurance company. This part of the analysis is based on a constant volatility. Given that the insurance company is informed of regulatory rules, we study how results can be significantly different when the insurance company follows a risk management strategy with non-constant volatilities. We thus highlight some limits of the prior literature and believe that the risk management strategy of the company should be taken into account in the estimation of the risk exposure as well as in that of the market value of liabilities.     

Limiting properties of the occurrence/exposure rate and simple risk rate

In this paper, we study the asymptotic distributions of the functions of the occurrence/exposure rates of several groups of patients as well as Berry-Esseen bound on the distribution function of the occurrence/exposure rate. Asymptotic distributions of functions of the simple risk rates are also derived. The results are useful in not only medical research but also in the area of reliability.The work of the first two authors was supported by Contract F49620-C5-C-0008 of the Air Force Office of Scientific Research. The United States Government is authorized to reproduce and distribute reprints for governmental purposes.     

On cross-risk vulnerability

We introduce the notion of cross-risk vulnerability to generalize the concept of risk vulnerability introduced by Gollier and Pratt [Gollier, C., Pratt, J.W. 1996. Risk vulnerability and the tempering effect of background risk. Econometrica 64, 1109–1124]. While risk vulnerability captures the idea that the presence of an unfair financial background risk should make risk-averse individuals behave in a more risk-averse way with respect to an independent financial risk, cross-risk vulnerability extends this idea to the impact of a non-financial background risk on the financial risk. It provides an answer to the question of the impact of a background risk on the optimal coinsurance rate and on the optimal deductible level. We derive necessary and sufficient conditions for a bivariate utility function to exhibit cross-risk vulnerability both toward an actuarially neutral background risk and toward an unfair background risk. We also analyze the question of the sub-additivity of risk premia and show to what extent cross-risk vulnerability provides an answer.     

考虑需求和质量双重风险的动力电池回收定价策略和协调机制研究

合理的定价策略和有效的协调机制是保障即将大量报废的动力电池实现回收利用的重要手段。本文同时考虑动力电池回收利用中来自市场的需求风险和来自回收渠道的质量风险,构建了两阶段逆向供应链分散式和集中式定价模型,发现分散决策下的最优回收价格始终低于集中决策下的最优回收价格,逆向供应链存在双重边际化现象;进一步,基于风险共享契约提出完全补偿契约来协调供应链,从而使供应链成员实现帕累托改进,并结合具体算例提出了相应的建议。     

Risk theory insight into a zone-adaptive control strategy

The main purpose of this paper is a risk theory insight into the problem of asset-liability and solvency adaptive management. In the multiperiodic insurance risk model composed of chained classical risk models, a zone-adaptive control strategy, essentially similar to that applied in Directives [Directive 2002/13/EC of the European Parliament and of the Council of 5 March 2002, Brussels, 5 March 2002], is introduced and its performance is examined analytically. That examination was initiated in [Malinovskii, V.K., 2006b. Adaptive control strategies and dependence of finite time ruin on the premium loading. Insurance: Math. Econ. (in press)] and is based on the application of the explicit expression for the finite-time ruin probability in the classical risk model. The result of independent interest in the paper is the representation of that finite-time ruin probability in terms of asymptotic series, as time increases.     

Nonparametric regression with interval-censored data

In many medical studies,the prevalence of interval censored data is increasing due to periodic monitoring of the progression status of a disease.In nonparametric regression model,when the response variable is subjected to interval-censoring,the regression function could not be estimated by traditional methods directly.With the censored data,we construct a new response variable which has the same conditional expectation as the original one.Based on the new variable,we get a nearest neighbor estimator of the regression function.It is established that the estimator has strong consistency and asymptotic normality.The relevant simulation reports are given.