慢性高眼压动物模型视网膜中睫状神经生长因子及其受体的表达

目的观察慢性高眼压动物模型视网膜中CNTF及CNTFRα的定位及表达变化。方法选取健康新西兰大白兔为实验对象建立兔慢性高眼压模型。选取造模成功的24只(48眼)兔慢性高眼压眼,随机分为4组慢性高眼压模型组,每组6只(12眼),分别存活7、14、21、28d。另设正常兔6只(12眼)为假手术对照组(简称对照组)。免疫组织化学染色方法测定兔视网膜中CNTF及CNTFRα的定位及表达变化。结果在对照组中,RGCs层均有大量的CNTF及CNTFα存在,在其它各层也存在散在颗粒状分布的CNTF及CNTFRα。慢性高眼压损伤后,CNTF及CNTFRα在视网膜各层显著增加,并呈弥漫性分布,造模后7、14d与正常对照组比较相差非常显著(P<0.01)。在造模后7d,是CNTF及CNTFRα在视网膜各层表达的高峰,在造模后28d两者的表达均显著高于正常对照组(CNTF:P<0.05;CNTFR:P<0.05)。结论慢性高眼压损伤导致视网膜CNTF和CNTFRα表达量的增加和分布的改变。     

高眼压情况下青光眼小梁切除术的探讨

青光眼是眼科常见疾病,由于眼内压间断或持续升高的水平超出眼球所能耐受的最大程度,导致眼内各组织及视功能受到不同程度的损害[1]。患者会出现视神经萎缩、视力下降、视野减小,甚至可能出现失明,一般情况下眼内压越高,对眼的损害越大。因此,测定眼内压是诊断、治疗青光眼和评价其疗效的重要依据,也只有将眼内压控制到合适范围才能减缓青光眼的进一步发展。部分患者采用药物治疗则可以较好的控制眼压[2],另有部分患者     

内核－边层：可控的放权式改革－对中国改革的政治学解读

本文认为,中国改革的动因与进程来自于内部,来自于内核一边层权力结构的延续性。权力边层率先发起对统制主义的单一性体制的冲击。从改革的发生看,中国的改革属于放权式改革,只是在放权过程中产生了分权的后果。而放权式改革本身就意味着是可控的,权力内核可以控制改革的速率和领域,从而避免改革可能出现的激烈震荡。改革后的体制创新,使权力内核和边层处于新的互动过程中。由于边层已发生重大变化,权力内核必须作出调适性改革。     

上市公司高管层货币性报酬影响因素实证研究

在委托代理理论的框架下,对我国国有企业薪酬演变制度背景进行了分析。利用2001年￣2004年沪市上市公司的数据,对高管人员货币性薪酬的影响因素进行了检验。结果表明:货币性薪酬水平与公司期初资产总额、规模、总资产报酬率是正相关关系;与国有股比例是负相关关系,报酬激励受转轨经济中的管制约束;与主营业务收入增长率关系为负。     

我国上市公司高管层股权激励中存在的问题及对策研究

高管层股权激励是上市公司管理中的重要机制,是极为重要的薪酬激励模式之一。高管层股权激励加强了公司股东与高管之间的利益关系,促进公司高管为股东创造更多的利益。就此,以上市公司的高管股权激励为研究对象,初步探讨高管股权激励的基本类型和特点,对我国上市公司高管层股权激励中存在的问题进行分析研究,并提出一些行之有效的对策。     

Cost-effectiveness analysis of standalone trabecular micro-bypass stents in patients with mild-to-moderate open-angle glaucoma in Canada

Objectives: To estimate the cost-utility of two trabecular micro-bypass stents (TBS) implantation vs standard of care (SOC) in patients with mild-to-moderate open-angle glaucoma (OAG) in the Canadian healthcare setting.

Methods: The deterioration in visual field (VF) defect over a 15-year time horizon was tracked using a Markov model with Hodapp-Parrish-Anderson stages of glaucoma (mild, moderate, advanced, severe/blind) and death as health states. Meta-analyses of randomized clinical trials were conducted to estimate the pooled reduction in intraocular pressure (IOP) and medication use due to TBS and SOC. The rate of decline in VF loss was adjusted by the extent of IOP reduction to estimate transition probabilities. Healthcare resource utilization, unit costs (2017 CAD), and progression-related utility scores were obtained by literature review, and medication costs with wastage were obtained from IMS Brogan PharmaStat. The impact of parameter and methodological uncertainty on costs and quality-adjusted life years (QALYs) was examined using probabilistic and 1-way sensitivity analyses.

Results: The meta-analysis showed an additional reduction of 1.13 medications/patient and an additional decrease in IOP of –1.10?mmHg at 36?months favoring TBS. TBS strongly dominated medication alone, due to higher improvement in quality-of-life (0.068 QALYs), fewer blind eyes (–0.0031), and a decrease in total healthcare costs of C$2,908.3 per patient over the time horizon (C$9,394.1 TBS vs C$12,302.4 medication alone). Sensitivity analyses showed that results were robust to the uncertainties in model inputs and assumptions. Time-to-dominance was 44?months (3.7?years).

Conclusions: The TBS procedure was cost-effective over SOC in a 15-year time horizon, with quality-of-life gains.     

Concurrent trading in two experimental markets with demand interdependence

Summary. We report results from fifteen computerized double auctions with concurrent trading of two commodities. In contrast to prior experimental markets, buyers' demands are induced via CES earnings functions defined over the two traded goods, with a fiat money expenditure constraint. Sellers receive independent marginal cost arrays for each commodity. Parameters for buyers' earnings functions and sellers' costs are set to yield a stable, competitive equilibrium. In spite of the complexity introduced by the demand interdependence, the competitive model is a good predictor of market outcomes, although prices tend to be above (below) the competitive prediction in the low-price (high-price) market.     

An experimental study of commitment in Stackelberg games with observation costs

We report on experiments examining the value of commitment in Stackelberg games where the follower chooses whether to pay some cost to perfectly observe the leader's action. Várdy [Games Econ. Behav. (2004)] shows that in the unique pure-strategy subgame perfect equilibrium of this game, the value of commitment is lost completely; however, there exists a mixed-strategy subgame perfect equilibrium where the value of commitment is fully preserved. In the data, the value of commitment is largely preserved when the cost of looking is small, while it is lost when the cost is large. Nevertheless, for small observation costs, equilibrium behavior is clearly rejected. Instead, subjects persistently play non-equilibrium strategies in which the probability of the follower choosing to observe the leader's action is a decreasing function of the observation cost.     

Technology adoption in markets with network effects: Theory and experimental evidence

We examine a technology-adoption game with network effects in which coordination on either technology A or technology B constitutes a Nash equilibrium. Coordination on technology B is assumed to be payoff dominant. We define a technology’s critical mass as the minimal share of users, which is necessary to make the choice of this technology the best response for any remaining user. We show that the technology with the lower critical mass implies risk dominance and selection by the maximin criterion. We present experimental evidence that both payoff dominance and risk dominance explain participants’ choices in the technology-adoption game. The relative riskiness of a technology can be proxied using either technologies’ critical masses or stand-alone values absent any network effects.     

Work productivity loss due to flares in patients with chronic gout refractory to conventional therapy

Abstract

Objective:

Joint pain and swelling during gout flares may lead to considerable morbidity and disability, having an impact on patient work productivity and social participation. The objective of this study was to assess how gout flares affect these activities in patients with chronic gout refractory to conventional therapy.

Methods:

A 1-year prospective observational study was conducted among patients with symptomatic disease in the United States in 2001. Inclusion criteria required patients (1) to be age 18 years or older, (2) to have documented, crystal-proven gout, (3) to have symptomatic gout, and (4) to be intolerant or unresponsive to conventional therapy, reflected by SUA?≥?6.0?mg/dL. Patients were evaluated every 2 months. At each visit, patients completed a gout diary, which included number of flares experienced, duration and severity of each flare, and whether the flare caused: (1) work loss, (2) missed appointments or social events, or (3) impairment of self-care activities. The Short-Form Health Survey (SF-36) was also completed each visit.

Results:

Analyses were restricted to those who completed the first 6 months of the study (n?=?81). Mean number of flares per patient per year was 8.8. Of the patients who were <65 years, 78% reported at least 1 work day lost due to a gout attack during the year. Mean annual work day loss for those <65 years was 25.1 days. A total of 545 of patients reported at least one flare per year that impaired social activities, with a mean of 17.1 social days lost and 52% reported at least one flare per year that compromised normal self-care activities, with a mean of 16.9 days impairment. Correlations between the diary reports and activity-related questions from the SF-36 were significantly positive.

Limitations:

The study is limited by small sample size, lack of reference group, and inability to explicitly collect employment information. Age under 65 years was used as a proxy for employment eligibility.

Conclusion:

Flares in patients with chronic gout refractory to conventional therapy significantly affect patient work productivity and social activities.     

Costs associated with adverse events in patients with metastatic renal cell carcinoma

Objective:

To estimate adverse event (AE) costs in patients receiving targeted therapies for the first line treatment of metastatic renal cell carcinoma (mRCC).

Methods:

Retrospective study based on healthcare claims data for patients with mRCC, aged ≥18 years, receiving first-line treatment with targeted therapies. AEs of interest comprised of abdominal pain, back pain, diarrhea, dyspnea, extremity pain, fatigue/asthenia, hand-foot syndrome, hypertension, lymphopenia, nausea/vomiting, neutropenia, proteinuria, and thrombocytopenia. Healthcare encounters for AEs were based on ICD-9-CM diagnosis/procedure codes on healthcare claims. AE costs were examined over a 30-day period, beginning with the date of first mention of AE, and were estimated based on the difference in total costs between patients with and without events. Drug costs of targeted agents were excluded from the analysis. Multivariate generalized linear models with a log-link function and gamma response probability distribution were utilized to control for differences in baseline characteristics between patients with and without evidence of AEs.

Results:

A total of 533 patients were included in this analysis: 418 patients with AE and 115 patients without AE. Baseline characteristics were generally similar between patients in the two groups. The GLM-based estimate of incremental 30-day post-event costs among patients with evidence of any adverse events was $9807 (95% CI?=?$4386–$22,947). For all types of adverse events examined, the estimated difference in costs between evented and non-evented patients was positive; the 95% CI did not include zero for all of the adverse events considered, except hypertension and proteinurea. Study limitations include errors of commission/omission, especially as they may affect case-finding methods that rely on ICD-9-CM diagnosis and procedure codes, as was the case in the current study.

Conclusion:

Costs associated with AEs of first-line targeted therapies are substantial in patients with mRCC. Efforts to prevent and/or better manage these events may reduce overall healthcare costs.     

Testing the TASP: An experimental investigation of learning in games with unstable equilibria

We report experiments studying mixed strategy Nash equilibria that are theoretically stable or unstable under learning. The Time Average Shapley Polygon (TASP) predicts behavior in the unstable case. We study two versions of Rock-Paper-Scissors that include a fourth strategy, Dumb. The unique Nash equilibrium is identical in the two games, but the predicted frequency of Dumb is much higher in the game where the NE is stable. Consistent with TASP, the observed frequency of Dumb is lower and play is further from Nash in the high payoff unstable treatment. However, Dumb is played too frequently in all treatments.     

Investment decisions and coordination problems in a market with network externalities: An experimental study

We study decision-making and the associated coordination problems in an experimental setting with network externalities. Subjects decide simultaneously in every round how much to invest out of a fixed endowment; the gain from an investment increases with total investment, so that an investment is profitable iff total investment exceeds a critical mass. The game has multiple, Pareto-ranked equilibria; we find that whether first-round total investment reaches critical mass predicts convergence towards the Pareto optimal full-investment equilibrium. Moreover, first-round investments and equilibrium convergence vary with critical mass and group size in a complex way that is explicable by subtle effects of strategic uncertainty on decision making.     

The role of risk aversion in public goods dilemmas with environmental uncertainty: an experimental analysis

The purpose of this study is to extend earlier research on environmental uncertainty in public goods dilemmas. The present paper reports the results of an experiment designed to examine the effect of risk aversion on public goods provision. A von Neumann–Morgenstern utility function with constant coefficient of relative risk aversion is used to investigate the impact of risk attitudes within a threshold public goods environment. The outcome of the threshold public goods experiment shows that subjects are indifferent to the changes in environmental conditions. Additionally, the analysis indicates that risk aversion is a significant determinant of voluntary public goods contribution level.