Box-Behnken设计法优化奥沙利铂脂质体的处方工艺

目的 采用Box-Behnken实验设计法优化奥沙利铂（oxaliplatin,Ox）脂质体的制备工艺。方法 以磷脂质量浓度（X1）、磷脂与Ox质量比（X2）和磷脂与胆固醇质量比（X3）为考察对象,以包封率（Y）为评价指标,采用三因素三水平的Box-Behnken实验设计筛选奥沙利铂脂质体最佳的处方。结果 最优处方是磷脂质量浓度为10.20g·L1,磷脂与药物的质量比为31∶1,脂质体膜材料中磷脂与胆固醇质量比为3.8∶1。包封率的预测值与理论值偏差较小。结论 Box-Behnken实验设计法可用于奥沙利铂脂质体的处方优化。     

沙美特罗替卡松联合BiPAP在慢性阻塞性肺疾病治疗中的应用研究

目的：探讨沙美特罗替卡松联合双水平气道正压通气（BiPAP）在慢性阻塞性肺疾病（COPD）合并呼吸衰竭治疗中的应用价值。方法：选取本院2007年7月~2011年3月收治的250例COPD合并Ⅱ型呼吸衰竭患者的临床资料,随机分为治疗组（130例）和对照组（120例）,对照组患者采用沙美特罗替卡松粉吸入剂治疗,治疗组患者采用沙美特罗替卡松粉吸入剂联合BiPAP呼吸机治疗,随访4周,比较两组患者动脉血气分析及肺功能变化情况。结果：治疗组患者肺功能及动脉血气分析明显优于对照组,两组患者比较差异有统计学意义（P〈0.05）。结论：沙美特罗替卡松联合BiPAP呼吸机治疗慢性阻塞性肺疾病,疗效满意,值得在临床推广。     

Topology Optimization of Piezoelectric Energy Harvesters for Enhanced Open-Circuit Voltage Subjected to Harmonic Excitations

Energy harvesting devices made of piezoelectric material are highly anticipated energy sources for power wireless sensors. Tremendous efforts have been made to improve the performance of piezoelectric energy harvesters (PEHs). Noticeably, topology optimization has shown an attractive potential to design PEHs with enhanced energy conversion efficiency. In this work, an alternative yet more practical design objective was considered, where the open-circuit voltage of PEHs is enhanced by topologically optimizing the through-thickness piezoelectric material distribution of plate-type PEHs subjected to harmonic excitations. Compared to the conventional efficiency-enhanced designs, the open-circuit voltage of PEHs can be evidently enhanced by the proposed method while with negligible sacrifice on the energy conversion efficiency. Numerical investigations show that the voltage cancellation effect due to inconsistent voltage phases can be effectively ameliorated by optimally distributed piezoelectric materials.     

医用外科口罩和防护口罩生物气溶胶过滤效率的评价

目的:对医用外科口罩和防护口罩的颗粒过滤效率(particle filtration efficiency,PFE)、细菌过滤效率(bacte-rial filtration efficiency,BFE)及病毒过滤效率(viral filtration efficiency,VFE)进行评价.方法:参照YY 0469...     

Experimental evidence of physician social preferences

Physicians’ professional ethics require that they put patients’ interests ahead of their own and that they should allocate limited medical resources efficiently. Understanding physicians’ extent of adherence to these principles requires understanding the social preferences that lie behind them. These social preferences may be divided into two qualitatively different trade-offs: the trade-off between self and other (altruism) and the trade-off between reducing differences in payoffs (equality) and increasing total payoffs (efficiency). We experimentally measure social preferences among a nationwide sample of practicing physicians in the United States. Our design allows us to distinguish empirically between altruism and equality–efficiency orientation and to accurately measure both trade-offs at the level of the individual subject. We further compare the experimentally measured social preferences of physicians with those of a representative sample of Americans, an “elite” subsample of Americans, and a nationwide sample of medical students. We find that physicians’ altruism stands out. Although most physicians place a greater weight on self than on other, the share of physicians who place a greater weight on other than on self is twice as large as for all other samples—32% as compared with 15 to 17%. Subjects in the general population are the closest to physicians in terms of altruism. The higher altruism among physicians compared with the other samples cannot be explained by income or age differences. By contrast, physicians’ preferences regarding equality–efficiency orientation are not meaningfully different from those of the general sample and elite subsample and are less efficiency oriented than medical students.

In a classic article, Kenneth Arrow (1) argued that asymmetric information pervades the health-care market. Patients rely on physicians’ expert knowledge in planning their medical care. Health insurers and government agencies (Medicare and Medicaid) largely rely on physicians to decide which treatments are appropriate for their patients. This deference to physicians’ authority may be justified given their superior expertise and informational advantages (2). However, the dual role of recommending and providing treatments creates opportunities for physicians to place their interests ahead of their patients’ interests, for example by recommending profitable tests and treatments that offer little or no health benefits. A second risk is more subtle. Physicians must trade off their individual patients’ interests in getting care, even if the benefit is likely to be small, against society’s interest in allocating limited medical resources efficiently, in order to generate the greatest benefits for the overall health of a population.The norms of physician professionalism—including, in particular, the patient-centered norms that constitute physicians’ traditional professional ethic—are intended to address the risk of selfishness. Arrow argues that due to information asymmetry, the principle of“buyer beware” that governs ordinary consumer markets should be replaced, in health care, by the physicians’ professional responsibility to put patients’ interests ahead of their own (1). Physician leaders publicly promote the importance of professionalism, while exhorting physicians to act altruistically. For example, the editors of the New England Journal of Medicine have asserted that “medicine is one of the few spheres of human activity in which the purposes are unambiguously altruistic” (3), while the American Board of Internal Medicine similarly asserts that “altruism is the essence of professionalism … the best interest of patients, not self-interest, is the rule” (4). On the other hand, empirical studies have suggested that, at least in some situations, some physicians create “supplier-induced demand,” which influences a patient’s demand for care “against the physician’s interpretation of the best interest of the patient” (5), contributing to skepticism about whether physicians do in fact behave altruistically. [Such skepticism is not limited to medicine. Legal ethics, for example, has long sought to control lawyers’ abuse of discretion through professional norms of client loyalty and care (6). But skeptics have cast these norms as self-serving, and the law governing lawyers increasingly subjects them to elaborate institutionalized mechanisms of bureaucratic control.]While the effects of professional norms on physician behavior are difficult to measure directly, a clearer understanding of physicians’ social preferences can help to illuminate whether professional norms and physicians’ individual preferences are oppositional or aligned. Our study therefore helps to evaluate the likely effectiveness of both professional norms and the turn to bureaucracy. While altruism and related professional norms are important in many other professions (7), the distinct characteristics of the market for medical care, namely information asymmetry and uncertainty in the relationship between medical treatments and patient outcomes (1), render it especially critical to study these issues among physicians.Health care systems in the US and elsewhere address the second risk—concerning efficiency—in more complex ways. Although professional ethics give physicians a responsibility to conserve scarce medical resources (8), the norm that directs individual physicians to put their patients first may render a norm-based approach inadequate to the problem of efficiency (9). Health insurers therefore use bureaucratic mechanisms and financial incentives to manage the information asymmetry between a physician who knows the specific patient’s situation and the insurer which does not (9).^*We deploy an incentivized economic experiment to investigate both altruism (the trade-off between self and other) and equality–efficiency orientation (the trade-off between reducing self–other differences in payouts and increasing payout totals) in practicing US physicians, and we compare our results with analogous experiments that measure parallel behaviors in other populations. A vast literature considers social preferences, and laboratory experiments have been very fruitful in both establishing the empirical reliability of such preferences and directing theoretical attention to them. [We will not attempt to review the enormous body of work in behavioral and experimental economics on social preferences. Camerer (10) provides a comprehensive discussion, if now somewhat dated, of the vast body of experimental and theoretical research in economics focusing on dictator, ultimatum, and trust games. Engel (11) provides the most comprehensive meta-study of dictator games.] After presenting our results, we relate them to the results from prior work that are particularly relevant to our study (Discussion). We note that the social preferences of physicians and professionals more generally remain relatively understudied, and our discussion of the relationship between our study and prior work explains the specific contributions that we make.Our sample consists of 284 physicians from 36 medical groups around the United States, including physicians in primary care (internal medicine and family medicine) and cardiology, and physicians in private practices and employed by hospitals. Our experiment gives subjects broad discretion to implement their preferences, free from bureaucratic control or even surveillance. Our results therefore inform the question whether norms are likely to affect physician choices along both dimensions of behavior. Our study measures altruism in a large multisite sample of practicing physicians and measures both dimensions of social preferences.Our experiment asked subjects to make trade-offs between their own self-interest and the interest of an anonymous other and, at the same time, between equality and efficiency. These two aspects of social preferences often operate together, but they remain conceptually distinct. [Social preferences can be weighted toward equality (reducing differences in payoffs) or weighted toward efficiency (increasing total payoffs) and range from pure utilitarian to maxmin or Rawlsianism. As the dispute between Harsanyi (12, 13) and Rawls (14) shows, fair-minded people (who are all perfectly impartial between self and other) can disagree about how to trade off equality and efficiency. The work of Harsanyi and Rawls, and of the many others who have followed them, has had broad-reaching influence across many disciplines, including philosophy, economics, and law.] To capture both of these features in our experiment, we employ a modified dictator game (15–17) in which we ask physicians to allocate real money between themselves and an anonymous other drawn from a broadly representative sample of the US population. Our experiment presents subjects with allocation decisions in which the “price of giving” varies across decision problems—sometimes the subject may need to sacrifice more than a token (the experimental currency)—to give a single token to other (the recipient); in other decisions, it may cost only a fraction of a token. These decisions are made through an intuitive “point-and-click” graphical interface in which the choices are represented as a budget line where each point represents a possible allocation. The slope of the line captures the price of giving tokens to other.^†Intuitively, this method allowed us to collect a rich dataset capable of measuring both altruism and equality–efficiency orientation at the level of the individual subject. [The importance of studying individual heterogeneity in social preferences is emphasized by Andreoni and Miller (17). Because of this heterogeneity, it is necessary to investigate behavior at an individual level. Our experimental design allows subjects to make numerous choices over a wide range of budget lines, and this yields a rich dataset that is well-suited to analysis at the individual level. It is clearly advantageous to estimate individual-level parameters and then generate individual-level distributions of the estimations rather than to pool data and then estimate population-level parameters.] The degree of altruism is reflected in the amount subjects give on average, whereas equality–efficiency orientation is captured by how subjects respond to the price of giving. Increasing the fraction of the budget spent on other as the price of giving increases indicates social preferences weighted toward equality (reducing the difference in payoffs between self and other), whereas decreasing it when the price of giving increases indicates social preferences weighted toward efficiency (increasing the total payoffs to self and other). We rely on techniques developed in our prior work (15, 16, 18) to evaluate the consistency of physicians’ choices (i.e., whether they reflect a complete and transitive preference ordering) and to explore the structure of the social utility functions that rationalize the observed data.We further compare physicians’ preferences with preferences previously measured in three other populations using equivalent experiments: 1) a broadly representative sample of US adults (18), 2) an “elite” subsample of those who hold a graduate degree and have an annual household income over $100,000 (15, 18), and 3) a sample of medical students from nine schools around the United States (19, 20). The social preferences of these populations provide important benchmarks against which physicians’ social preferences can be assessed; furthermore, the comparison with medical students may shed light on whether physicians’ distinctive social preferences reflect a “selection effect” based on who enters medicine or a “treatment effect” of practicing medicine.^‡We begin our analysis of the experimental data by using classical revealed preference theory (21–23) to test whether subjects’ choices are consistent with the essence of all traditional models of economic decision-making—utility maximization.^§ Our physician subjects exhibit a remarkably high degree of consistency when compared with other populations, including medical students and also students from Yale Law School (YLS), the population that had exhibited the highest degree of consistency in prior experiments (15). [In our subsequent analysis, we do not draw detailed comparisons between our physician sample and the sample YLS students (15). The experimental design in Fisman et al. (15) differs from the current one in that the YLS student subjects were asked to allocate money between themselves and another student, rather than an individual drawn from a sample broadly representative of the US adults.] This result reveals that our physician subjects are highly adept at implementing a consistent, well-behaved social preference ordering. This makes it natural to estimate—at the level of the individual subject—the substantive social preferences that physicians display.We then estimate social preferences at the level of the individual physician using a constant elasticity of substitution (CES) utility function commonly employed by economists in demand analysis. The CES functional form is appealing because the degree of altruism and equality–efficiency orientation are each independently represented in a precise and transparent manner through its two parameters, which we estimate separately for each subject (further details on the CES specification and estimation are provided in Empirical Framework).We find that physicians are more altruistic than any other population, while physicians’ preferences concerning the trade-off between equality and efficiency are almost indistinguishable graphically from the preferences of the American Life Panel (ALP) elites and also the broader ALP sample. These findings on physicians’ distinctive social preferences have direct and concrete implications for professionalism, incentives, and bureaucratic rules directed at physicians. Insofar as physicians are altruistic, they may be more likely to live up to the professional ideal of putting patients’ interests ahead of their own. At the same time, altruism as captured in our experiment is far from ubiquitous, even among physicians and, furthermore, physicians’ efficiency orientation is indistinguishable from than that of the general population. Taken together, our findings suggest that the ideal of physician professionalism—putting the patient first—is not merely a self-serving myth but that other mechanisms may be required to support the quality of medical care and to promote efficient allocation of medical resources.     

力量支持协同护理模式在经口喂养不耐受<34孕周新生儿中的应用

目的:探讨力量支持协同护理模式在经口喂养不耐受<34孕周新生儿中的应用效果。方法:选取2019年1月—2020年8月收治的102例<34孕周经口喂养不耐受新生儿作为研究对象,将2019年1月—2019年10月接受常规护理的51例患儿作为对照组,将2019年11月—2020年8月接受力量支持协同护理模式的51例患儿作为观察组。比较两组经口喂养进程(留置胃管时间、过渡时间、住院时间)、喂养效率及患儿行为状态变化。结果:观察组患儿留置胃管时间、过渡时间、住院时间均短于对照组(P<0.05);观察组患儿干预第3天、实现全口喂养时吸吮效率和喂养效率均高于对照组(P<0.05);观察组患儿干预3 d、干预5 d后行为状态优于对照组(P<0.05)。结论:力量支持协同护理模式能有效改善早产儿经口喂养表现,减轻经口喂养不耐受症状,进一步推进经口喂养进程,缩短经口喂养过渡时间。     

电子护理病历与手工护理病历优势比较的研究

目的 比较电子护理病历与手工护理病历的不同书写方式,从中找出丽者的差异.方法 采用临床调查的方式.2010年8月1-30日手工护理病历2031份,平均住院67.7人/天,为A组;2012年8月1-30日电子护理病历2132份,平均住院71人/天,为B组.调查体温表绘制、医嘱处理、护理记录书写速度、质量.手工护理病历与电子护理病历书写格式相同.结果 A组、B组体温表绘制耗时比较,A组:(82.93±1.92)批量/天(min),(1.23±0.02) min/份;B组:(14.97±0.46)批量/天(min),(0.21±0.00) min/份;t值分别为70.23与120.82,P均＜0.05.A组、B组医嘱处理耗时比较,A组:(187.93±5.89)批量/天(min),(2.78±0.05) min/份;B组:(80.67±3.05)批量/天(min),(1.13±0.04) min/份;t值分别为33.08与54.72,P均＜0.05.A组、B组书写耗时比较,首次护理记录单:A组(10.10±0.47) min,B组(2.85±0.21)min,t值为28.24,P＜0.05;护理记录单:A组(4.99±0.54)min/次,B组(1.72±0.23) min/次,t值为11.13,P＜0.05.结论 电子病历改变工作流程和方式,不仅提高工作效率和质量,还便于检索、查阅和管理护理病历.     

吉非替尼对肺鳞癌患者免疫功能的影响及其近期临床疗效

目的：研究吉非替尼对肺鳞癌患者免疫功能的影响及其近期临床疗效。方法选取诊断为肺鳞癌的患者84例,随机分为观察组和对照组,每组均为42例,两组患者均给予常规治疗,观察组在常规治疗的基础上给予口服吉非替尼,观察两组患者治疗后体液免疫和细胞免疫功能情况及其近期临床疗效。结果治疗后两组患者血清 CD3、CD4、IgG、IgM、IgA 浓度与 CD4／CD8较治疗前有所降低（P ＜0．05）,CD8较治疗前有所升高（P ＜0．05）;观察组患者血清 CD3、CD4、CD4／CD8、IgG、IgM、IgA 浓度明显高于对照组（P ＜0．05）,观察组 CD8较对照组低（P ＜0．05）;观察组临床疗效优于对照组,治疗后两组均出现恶心、恶心伴呕吐、骨髓抑制,差异无统计学意义（P ＞0．05）。结论在常规治疗的基础上给予口服吉非替尼能改善患者的免疫功能,提高临床疗效,且无严重不良反应。     

基于控墒补灌的春小麦滴灌制度研究

为优化北疆绿洲区滴灌春小麦的灌溉制度,采用控墒补灌法研究了不同灌水量对滴灌春小麦光合特征、干物质分配及水分利用效率的影响。结果表明,拔节～开花期小麦株高、干物质积累量和叶面积指数均随着灌水量的增加显著（P<0.05）升高。小麦旗叶各时期净光合（Pn）、气孔导度（Gs）和蒸腾速率（Tr）增加显著（P<0.05）升高,而胞间CO₂浓度（Ci）变化趋势相反;过量灌溉T5各时期Gs均有所降低,Pn和Tr成熟期下降显著（P<0.05）;亏缺灌溉（T1）Pn峰值提前至孕穗期,各时期WUE均最低、LS最高。干物质向籽粒的分配、花前同化物转运率和对籽粒的贡献率随墒度随灌水量增加显著（P<0.05）降低。二次曲线拟合表明,灌水量为371 mm时可取得7 450 kg·hm^-2的高产,灌溉频率约每7 d灌1次是本地区春小麦的最佳灌溉方案。     

多肽合成中"困难序列"的缩合研究进展

化学学科发展至今拥有极强的能力来获得高的合成效率，但是在多肽合成中“困难序列”的存在仍然成为成功缩合的巨大挑战。本文综述了影响多肽缩合效率的因素以及提高“困难序列”缩合效率的有效方法。所述方法均简便易行，适用于多肽的固相合成或液相合成。