不同清洗方法对血渍干涸器械清洗质量的对比

目的 探讨医院血渍干涸器械有效的清洗方法,以提高清洗质量,保证灭菌效果。方法 选择人工血液污染的金属器械1 800件,分为三组,每组齿牙器械500件,管腔类器械100件,分别接受直接机洗（常规组）、酶泡加机洗（试验A组）、酶液超声加机洗（试验B组）进行清洗,评价清洁合格率并进行对比。结果 目测显示：常规组、试验A组、试验B组的合格率分别为66.17%、86.83%、100.00%;放大镜检测：常规组、试验A组、试验B组的合格率分别为60.17%、82.33%、100.00%;潜血检测：常规组、试验A组、试验B组的合格率分别为60.00%、81.67%、100.00%,三组两两比较,差异均有统计学意义（P〈0.05）。结论 酶液超声加机洗的器械清洗方法的清洁效果明显优于其他两种方法。     

Theoretical Methods of Domain Structures in Ultrathin Ferroelectric Films: A Review

This review covers methods and recent developments of the theoretical study of domain structures in ultrathin ferroelectric films. The review begins with an introduction to some basic concepts and theories (e.g., polarization and its modern theory, ferroelectric phase transition, domain formation, and finite size effects, etc.) that are relevant to the study of domain structures in ultrathin ferroelectric films. Basic techniques and recent progress of a variety of important approaches for domain structure simulation, including first-principles calculation, molecular dynamics, Monte Carlo simulation, effective Hamiltonian approach and phase field modeling, as well as multiscale simulation are then elaborated. For each approach, its important features and relative merits over other approaches for modeling domain structures in ultrathin ferroelectric films are discussed. Finally, we review recent theoretical studies on some important issues of domain structures in ultrathin ferroelectric films, with an emphasis on the effects of interfacial electrostatics, boundary conditions and external loads.     

关于“得气”的古今认识和近10年研究情况的分析

ObjectiveWith the development of science of acupuncture and moxibustion, people have, in the knowledge of “deqi”, developed from subjective level to the quantitative level, and discovered many factors influencing the “deqi” of acupuncture. In this report, the relationship between “deqi” and these factors was explored in terms of different acupuncture methods and quantity and depth of stimulus.MethodsAncient literature about “deqi”, as well as related literature for clinical and basic research on “deqi” in recent 10 years were systematically collected.Results(1) Cerebral functional imaging technology and the scale of “deqi” were the most common quantitative indexes for “deqi” in recent 10 years. (2) There were many factors influencing “deqi” in acupuncture, which involved personal physiological status, nature of disease, anatomical features under the acupoint, different acupuncture methods, quantity and depth of stimulus, etc. Different acupuncture methods, quantity and depth of stimulus would bring different influences on and mechanisms of “deqi”.Conclusions(1) “Deqi” is not equal to needling sensation; (2) recessive needling sensation should be re-recognized; (3) the sensation of doctor should be paid attention; (4) The meaning of “deqi” should be re-defined and re-understood.     

Choosing the net survival method for cancer survival estimation

BackgroundA new net survival method has been introduced by Pohar Perme et al. (2012 [4]) and recommended to substitute the relative survival methods in current use for evaluating population-based cancer survival.MethodsThe new method is based on the use of continuous follow-up time, and is unbiased only under non-informative censoring of the observed survival. However, the population-based cancer survival is often evaluated based on annually or monthly tabulated follow-up intervals. An empirical investigation based on data from the Finnish Cancer Registry was made into the practical importance of the censoring and the level of data tabulation. A systematic comparison was made against the earlier recommended Ederer II method of relative survival using the two currently available computer programs (Pohar Perme (2013) [10] and Dickman et al. (2013) [11]).ResultsWith exact or monthly tabulated data, the Pohar-Perme and the Ederer II methods give, on average, results that are at five years of follow-up less than 0.5% units and at 10 and 14 years 1–2% units apart from each other. The Pohar-Perme net survival estimator is prone to random variation and may result in biased estimates when exact follow-up times are not available or follow-up is incomplete. With annually tabulated follow-up times, estimates can deviate substantially from those based on more accurate observations, if the actuarial approach is not used.ConclusionAt 5 years, both the methods perform well. In longer follow-up, the Pohar-Perme estimates should be interpreted with caution using error margins. The actuarial approach should be preferred, if data are annually tabulated.     

Adolescents’ Food Choice and the Place of Plant-Based Foods

A diet dominated by plant foods, with limited amounts of refined processed foods and animal products conveys substantial health benefits. This study sought to explore adolescents’ attitudes and perceptions towards plant-based foods. Semi-structured focus group interviews were conducted with adolescents (age 14–15 years) (n = 29) attending an inner city school in Yorkshire, UK. Using a grounded theory methodology, data analysis provided four main categories and related concepts revolving around adolescents’ perspectives on plant-based foods: food choice parameters; perceived drivers and benefits of plant-based foods; environmental food cues; barriers to plant-based food choice. In the emergent grounded theory, a clear disconnect between plant-based foods and the parameters that adolescents use to make food choices, is highlighted. Further, key barriers to adolescents adopting a plant-based diet are differentiated and considered with respect to practice and policy. The analysis offers a framework to remodel and re-present plant-based foods. In this way, it is proposed that a closer connection is possible, with consequent shifts in adolescents’ dietary behaviour towards a more plant-based diet and associated health benefits.     

A review of the effects of the cell environment physicochemical nanoarchitecture on stem cell commitment

Physicochemical features of a cell nanoenvironment exert important influence on stem cell behavior and include the influence of matrix elasticity and topography on differentiation processes. The presence of growth factors such as TGF-β and BMPs on these matrices provides chemical cues and thus plays vital role in directing eventual stem cell fate. Engineering of functional biomimetic scaffolds that present programmed spatio-temporal physical and chemical signals to stem cells holds great promise in stem cell therapy. Progress in this field requires tacit understanding of the mechanistic aspects of cell-environment nanointeractions, so that they can be manipulated and exploited for the design of sophisticated next generation biomaterials. In this review, we report and discuss the evolution of these processes and pathways in the context of matrix adhesion as they might relate to stemness and stem cell differentiation. Super-resolution microscopy and single-molecule methods for in vitro nano-manipulation are helping to identify and characterize the molecules and mechanics of structural transitions within stem cells and matrices. All these advances facilitate research toward understanding of stem cell niche and consequently to developing new class of biomaterials helping the “used biomaterials” for applications in tissue engineering and regenerative medicine.     

重酒石酸长春瑞滨长循环脂质体的制备与表征

目的采用pH梯度法制备重酒石酸长春瑞滨长循环脂质体并进行表征。方法以粒径为指标,考察水化温度和挤出次数对空白脂质体粒径的影响;以粒径及包封率为指标,考察孵化温度和孵化时间对载药脂质体粒径和包封率的影响。并采用Malvern粒度仪测定脂质体的粒径分布、多分散系数及Zeta电位,透射电镜考察其形态,并考察脂质体稳定性。结果重酒石酸长春瑞滨长循环脂质体粒径（96.4±27.2） nm,多分散系数（0.162±0.042）,Zeta电位（－26.7±3.5） mV;透射电镜显示脂质体粒径均一,成单层膜球状分布;长期稳定性研究显示,脂质体在5 ℃条件下放置3个月稳定。结论pH梯度法可以用于重酒石酸长春瑞滨长循环脂质体的制备。