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IntroductionOne of the current harm reduction debates in Australia concerns the legalisation of the extended distribution of sterile needles and syringes, a practice that is currently unlawful in most Australian settings.MethodsWe used data from a unique pilot program of authorised extended distribution to document the opinions held by 22 key stakeholders -service staff, drug users and police - about the risks and benefits of authorisation, and to analyse the ways in which drug users were understood within these.ResultsOpinions were strongly in favour of authorising extended distribution, based on the belief that this would reduce the transmission of hepatitis C. However, stakeholders also identified that distributors risked attention from police and some noted that the consequences of this would be borne by distributors themselves and not the services that support them. These opinions rested on specific assumptions about people who inject, some of which reflect negative constructions of drug users as a source of danger to the public or as helpless ‘addicts’ with little control over their risk reduction. But there were other representations that positioned drug users more positively as responsible agents with a strong duty of care to themselves and others whose choices are often limited by inadequate service structures. Staff participants drew on these understandings in careful and strategic ways, arguing for the rationality and expertise of drug users, while also problematizing the individualised approach that any form of authorised extended distribution might take.ConclusionWe argue that localised and incremental changes such as those that took place to support this pilot project, and the extensive support for extended distribution among stakeholders in this study including police, creates meaningful opportunities to think about extended distribution differently, which can in turn support conditions for future discussions about legislative change.  相似文献   
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Anaesthesia for endoscopic airway surgery involves unique challenges. The anaesthetist and surgeon are working in close anatomical proximity and the concept of shared airway is never more relevant. Understanding the planned procedure and the needs of the surgeon for access to the surgical field will enable the provision of anaesthesia and airway management using a variety of techniques. Planning for safe induction, maintenance and emergence of anaesthesia will also be guided by the specific pathology and patient characteristics and requires effective communication between the surgeon and anaesthetist.  相似文献   
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The mechanism of jet flow expanding into vacuum environment (or extremely low density environment) is important for the propulsion unit of micro-electro-mechanical systems (MEMS), the thruster of spacecraft, the attitude control system of satellite, etc.. Since its flow field is often composed of local continuum region and local rarefied region, the jet flow into vacuum has noteworthy multi-scale transportation behaviors. Therefore, the numerical study of such flows needs the multi-scale schemes which are valid for both continuum and rarefied flows. In the past few years, a series of unified methods for whole flow regime (from continuum regime to rarefied regime) have been developed from the perspective of the direct modeling, and have been verified by sufficient test cases. In this paper, the compressible conserved discrete unified gas-kinetic scheme is further developed and is utilized for predicting the jet flows into vacuum environment. In order to cover the working conditions of both aerospace and MEMS applications, the jet flows with a wide range of inlet Knudsen (Kn) numbers (from 1E-4 to 100) are considered. The evolution of flow field during the entire startup and shutdown process with Kn number 100 is predicted by the present method, and it matches well with the result of analytical collisionless Boltzmann equation. For Kn numbers from 1E-4 to 10, the flow field properties such as density, momentum, and pressure are investigated, and the results are provided in details, since the published results are not sufficient at the present stage. The extent and intensity of the jet flow influence are especially investigated, because they are strongly related to the plume contamination and momentum impact on objects facing the jet, such as the solar paddles which face the attitude control thruster during the docking process.  相似文献   
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We report a case of bronchopleural fistula (BPF) in a patient submitted to conventional mechanical ventilation in which high frequency jet ventilation (HFJV) was applied during five consecutive days. Gas exchange was adequate, the bronchial secretions could easily be cleared and the patient adapted comfortably to HFJV. In spite of PEEP levels between 4 and 8 mm Hg, the leak through the BPF ceased completely.  相似文献   
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目的 比较标准心肺复苏、主动按压减压心肺复苏、主动按压减压结合高频通气心肺复苏三种复苏法对心肺复苏循环效应影响 ;评价主动按压减压结合高频通气用于心肺复苏的可行性。方法 将9条犬经电击致颤制成心搏骤停模型 ,每只犬先后实施三种复苏法 ,①标准心肺复苏 ;②主动按压减压心肺复苏 ;③主动按压减压结合高频通气心肺复苏 ,实验顺序由随机法确定 ,每种复苏方法进行 5min ,待循环动力学稳定后记录收缩压、舒张压、心输出量。结果 收缩压、舒张压、心输出量均为主动按压减压结合高频通气模式大于主动按压减压心肺复苏模式 (P <0 0 1) ;主动按压减压心肺复苏模式大于标准心肺复苏模式 (P <0 0 1)。标准心肺复苏模式和主动按压减压心肺复苏模式胸外按压停顿期血压降至零 ,而主动按压减压结合高频通气心肺复苏模式血压持续稳定。结论 主动按压减压心肺复苏优于标准心肺复苏模式。主动按压减压结合高频通气心肺复苏模式既可产生较高的动脉血压、心输出量 ,又可提供充分的气体交换 ,值得进一步研究和推广应用  相似文献   
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目的 观察高频喷射通气结合小剂量氟碳 (3ml/kg)液体通气对吸入性损伤犬呼吸的功影响。方法 将 16条犬经蒸气吸入造成吸入性损伤模型 ,并随机分为两组 ,即对照组和治疗组。两组动物致伤后均行高频喷射通气 ,但治疗组动物同时经气管导管将氟碳液体 (3ml/kg)缓慢注入肺内 ,在 90min内测机械通气功 (WOBvent)。结果 治疗组在给予小剂量氟碳后的WOBvent与致伤后比较差异无显著意义 (P >0 0 5 ) ,对照组治疗后的WOBvent与致伤后比较差异亦无显著意义 (P >0 0 5 ) ,治疗组与对照组各时间点的WOBvent比较差异均无显著意义 (P >0 0 5 )。结论 高频喷射通气合并小剂量氟碳 (3ml/kg)部分液体通气并不增加动物的呼吸功。  相似文献   
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