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关键词： Electric field   Electric double layer   Direct electron transfer   Orientation   Denaturation   SELF-ASSEMBLED MONOLAYERS   FRUCTOSE/DIOXYGEN BIOFUEL CELL   MODIFIED GOLD ELECTRODES   HEART CYTOCHROME-C   DIRECT ELECTROCHEMISTRY   VOLTAMMETRIC RESPONSE   ESCHERICHIA-COLI   CYCLIC VOLTAMMETRY   REDOX PROTEINS   COPPER SITE  

摘要： Effects of the electrode poential on the activity of an adsorbed enzyme has been examined by using copper efflux oxidase (CueO) as a model enzyme and by monitoring direct electron transfer (DET)-type bioelectrocatalysis of oxygen reduction. CueO adsorbed on bare Au electrodes at around the point of zero charge (E-pzc) shows the highest DET activity, and the activity decreases as the adsorption potential (E-ad; at which the enzyme adsorbs) is far from E-pzc. We propose a model to explain the phenomena in which the electrostatic interaction between the enzyme and electrodes in the electric double layer affects the orientation and the stability of the adsorbed enzyme. The self-assembled monolayer of butanethiol on Au electrodes decreases the electric field in the outside of the inner Helmholtz plane and drastically diminishes the E-ad dependence of the DET activity of CueO. When CueO is adsorbed on bare Au electrodes under open circuit potential and then is held at hold potentials (E-ho) more positive than E-pzc, the DET activity of the CueO rapidly decreases with the hold time. The strong electric field with positive surface charge density on the metallic electrode (sigma(M)) leads to fatal denaturation of the adsorbed CueO. Such denaturation effect is not so serious at E-ho << E-pzc, but the electric field with negative sigma(M) induces an orientation inconvenient for the DET reaction during the adsorption process. A positively charged neomycin shows a promoter ability to Cue adsorbed at E-ad << E-pzc. The phenomenon is also explained on the proposed model. (C) 2014 Elsevier B.V. All rights reserved.

关键词： 医院感染   微生物检验   控制   应用效果  

摘要： 目的：分析充分发挥临床微生物检验在控制医院感染中的作用。方法：选择2013年12月到2014年12月期间在我院进行治疗的600例患者为研究对象，然后将其根据随机数字表分为两组，每组300例。其中一组作为观察组，该组患者在治疗时进行微生物检验。另一组作为观察组，该组患者在治疗时不进行微生物检验，然后对两组患者医院感染发生率和感染程度进行比较分析。结果：观察组的医院感染发生率和感染程度均明显低于对照组，两组之间的差异均有统计学意义（P〈0.05）。结论：对患者进行微生物检验可以有效控制医院感染，减少医院感染发生率和感染程度，效果理想，值得在临床上广泛推广。

关键词： eutrophication   Lake Taihu   nitrogen   nutrient management   phytoplankton   cyanobacterial blooms   phosphorus   LARGE SHALLOW LAKE   CHLOROPHYLL-ALPHA   NITROGEN   PHOSPHORUS   DOMINANCE   GROWTH   RATIOS   HPLC  

摘要： Rapidly increasing urban, agricultural, and industrial growth in the Taihu basin during the past four decades has led to accelerated nitrogen (N) and phosphorus (P) loading to the lake. This has caused the lake to shift from oligo-mesotrophic to hypertrophic conditions, symptomized by toxic cyanobacterial blooms, dominated by the non-N-2 fixing genus Microcystis. From 2008 to 2013, a series of in situ microcosm and mesocosm nutrient addition bioassays were conducted that were focused on the heavily polluted northern region (i.e., Meiliang Bay) and other lake locations. Bioassays showed that phytoplankton production, as chlorophyll a and photopigments diagnostic of major phytoplankton groups, was controlled by P inputs from spring to early summer, while N played a more dominant controlling role in summer-fall. In most cases, combined N and P additions promoted maximum growth. This pattern proved true for both the highly eutrophic northern region and the less-eutrophic central and southern regions. Cyanobacteria, chlorophytes, and cryptophytes all showed the strongest positive responses to N and N+P enrichment during the summer bloom period, while diatoms were the least abundant then and just moderately stimulated by nutrient additions. Cyanobacteria failed to selectively respond to P inputs during the summer bloom period, contradicting the paradigm that selective P enrichment will favor them, especially the N-2-fixing genera. Rather, Microcystis-dominated blooms remained N-limited during summer months and were not replaced by N-2-fixing genera, indicating that internal N and P regeneration of previously loaded nutrients must be sustaining blooms. Successful 'de-eutrophication' of Taihu will require reductions of both N and P inputs in all lake regions in order to control blooms and counter the legacy of several decades of nutrient over-enrichment.

关键词： contexts   methodology   ritual   prehistory   psychoactive substances   NEANDERTHAL BURIAL   FLOWER BURIAL   COASTAL PERU   SAN PEDRO   NIGER L.   OPIUM   ANTIQUITY   HISTORY   DRUGS   IDENTIFICATION  

摘要： The relationship between humans and psychoactive substances can be traced back over millennia. This paper aims to provide a comprehensive overview of the consumption of drug plants and fermented beverages in prehistoric times by drawing upon some archaeological examples worldwide that illustrate the early use of these substances. The archaeological evidence of psychoactive substances is assessed in the light of some indicators that should be taken into consideration when examining this type of data.

关键词： 质量检验   产品   管理活动   问题   建议  

摘要： 随着经济社会的发展,科学技术的进步,人们对产品的耐用性要求是越来越高,在追求物美价廉的基础上对产品的质量有了更深层次的要求。因此这也就衍生出了工业企业质检部门,为了尽可能的满足消费者的需求,质检部门就应该在产品质量检验中发挥重要的作用,严格,务实的把握好产品质量检验关,真正做到维护广大消费者的权益。本文就质检机构发挥的现实作用进行浅谈。

关键词： 尿糖   尿微量白蛋白   联合检验   糖尿病早期肾损伤  

摘要： 目的探究尿糖与尿微量白蛋白联合检验对糖尿病早期肾损伤的诊断价值。方法 233例早期糖尿病患者作为观察组,将同期进行健康体检的256名健康体检人员作为对照组。对此489名实验人员的临床资料进行回顾性分析。观察统计两组实验人员的尿糖与尿微量白蛋白含量。以临床检验数据来明晰尿糖与尿微量白蛋白联合检验对糖尿病早期肾损伤的诊断价值。结果观察组233例早期糖尿病患者的尿糖平均含量(3.62±0.32)mmol/L,尿微量白蛋白平均含量(172.54±9.63)μmol/L,而对照组健康体检人群的尿糖平均含量(1.22±0.44)mmol/L,尿微量白蛋白平均含量(16.88±1.64)μmol/L,两组实验人员的尿糖含量、尿微量白蛋白含量比较,差异有统计学意义(P<0.01)。结论糖尿病导致人体内环境大大改变,高糖环境对肾脏内部精细结构造成损害,无法截留原尿中的糖和蛋白成分。尿糖与尿微量白蛋白联合检验对糖尿病早期肾损伤有很好的诊断效果,与健康人群平均差值明显,有很明确的诊断作用,值得临床借鉴和推广。

关键词： 银行间债券市场   债券违约   违约风险   破产清算   资产剥离  

摘要： 2014年以来中国债券市场频现违约风险,目前我国债券市场背后仍存在隐性"刚性兑付"条件,几例临近违约的债券都采取了政府斡旋兜底,主承销商贷款支持的解决方案。但这不是长久之计,一个真正健康、健全的债券市场需要一套市场化的债券违约处理机制,本文将对此展开研究和探讨。

关键词： 检验检疫   技术   壁垒  

摘要： 出口法检目录大幅削减，但检验检疫仍然承担着法律赋予的进出口商品质量安全监管责任。新形势下，检验检疫应充分发挥自身优势，及时预警为政府、行业协会以及相关企业提供决策参考和依据。

关键词： English for Medical Purposes   English for Nursing   Internationally educated nurses   Corpus linguistics   Discourse analysis   LANGUAGE NEEDS   COMMUNICATION   STUDENTS   CARE   ENGLISH   TALKING   SKILLS  

摘要： Within English for Medical Purposes (EMP), one area of concern is to develop programs for international medical graduates (IMGs) working in the U.S. (Hoekje & Tipton, 2011). Along with IMGs, internationally educated nurses (IENs) are an increasingly important part of the U.S. workforce (Davis & Nichols, 2002). While communication difficulties for 1ENs are well documented (Davis & Nichols, 2002; Xu, 2007), few previous studies have investigated the discourse of IENs' interactions with patients. In order to inform IEN training programs, it is important to determine linguistic characteristics that distinguish IEN speech from that of U.S. nurses (USNs), native English speaking nurses born and trained in the U.S. To investigate differences between the two groups, a corpus of 102 nurse patient interactions (52 IENs and 50 USNs) was collected and analyzed for lexico-grammatical features. Results show that USNs used particular lexico-grammatical features more frequently, including past tense and various stance features (e.g., certainty adverbs such as maybe and kind of), all of which play an important role in creating rapport with patients and providing more patient-centered interactions. The findings have implications for IEN training programs, as well as EMP courses for nursing students and other medical professionals. (C) 2014 Elsevier Ltd. All rights reserved.

关键词： 输血检验   凝聚胺技术   作用  

摘要： 目的:进一步对凝聚胺技术在输血检验中所发挥的作用进行分析和探讨.方法:选取我院于2012年10月-2014年10月期间所采集的200例患者的血液样本,将其作为本次的研究对象,血液样本分别采用凝聚胺技术、盐水介质试验、木瓜酶试验、抗球蛋白试验等常规配血试验进行检验,并将所得到的结果进行对比,同时对其中50例疑难标本进行检查.结果:经过不同方法检验之后,凝聚胺技术较盐水介质试验、木瓜酶试验、抗球蛋白试验等常规配血实验的灵敏度较高,能够快速检测出IgG抗体.结论:在输血检验中,凝聚胺技术的操作较为简单,具有较高的灵敏度,能够有效预防临床输血过程中所出现的溶血性输血反应,在临床上具有极为重要的意义,今后值得推广和应用.