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IntroductionIt is a well-established fact that concomitant diseases can affect the outcome of total hip arthroplasty (THA). Therefore, careful preoperative assessment of a patient''s comorbidity burden is a necessity, and it should be a part of routine screening as THA is associated with a significant number of complications. To measure the multimorbidity, dedicated clinical tools are used.MethodsThe article is a systematic review of instruments used to evaluate comorbidities in THA studies. To create a list of available instruments for assessing patient''s comorbidities, the search of medical databases (PubMed, Web of Science, Embase) for indices with proven impact on revision risk, adverse events, mortality, or patient''s physical functioning was performed by two independent researchers.ResultsThe initial search led to identifying 564 articles from which 26 were included in this review. The measurement tools used were: The Charlson Comorbidity Index (18/26), Society of Anesthesiology classification (10/26), Elixhauser Comorbidity Method (6/26), and modified Frailty Index (5/26). The following outcomes were measured: quality of life and physical function (8/26), complications (10/26), mortality (8/26), length of stay (6/26), readmission (5/26), reoperation (2/26), satisfaction (2/26), blood transfusion (2/26), surgery delay or cancelation (1/26), cost of care (1/26), risk of falls (1/26), and use of painkillers (1/26). Further research resulted in a comprehensive list of eleven indices suitable for use in THA outcomes studies.ConclusionThe comorbidity assessment tools used in THA studies present a high heterogeneity level, and there is no particular system that has been uniformly adopted. This review can serve as a help and an essential guide for researchers in the field.  相似文献   
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小叶买麻藤中买麻藤甲素的结构研究   总被引:4,自引:0,他引:4  
从小叶买麻藤[Gnetum parvifolium(Warb.)C.Y.Cheng]茎的乙酸乙酯部分得到五个成分,经理化常数测定、光谱(UV,IR,MS,~1HNMR,~(13)CNMR和2D-NMR)分析和衍生物制备,确定买麻藤甲素为一个新的2-苯基苯并呋喃类化合物,结构为2-(3′,5′-二羟基-4′-甲氧基苯基)_-3-甲氧基5-羟基苯并呋喃。另外三个鉴定为异丹叶大黄素、白黎芦醇和β-谷甾醇.还有一个化合物正在鉴定中。  相似文献   
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麻黄碱在受热时可挥发,在蒸除提取溶剂时相随挥发损失,不能用常规的提取重量法测定。使用本室新近研制的涂圈压电传感器作为超微量质量敏感元件,取常规提取重量法的基本原理,并加以改进,可以实现麻黄碱的快速分析,从而扩大该经典方法的应用范围。本法可测定低至亚μg级的麻黄碱,具有方法简便、灵敏度高等优点。  相似文献   
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OBJECTIVES: The aim of this study was to assess the level of occupational exposure to nitrous oxide (N(2)O) in operating rooms (ORs), as related to different ventilation and scavenging systems used to remove waste anaesthetic gases from the work environment. METHODS: The monitoring of N(2)O in the air covered 35 ORs in 10 hospitals equipped with different systems for ventilation and anaesthetic scavenging. The examined systems included: natural ventilation with supplementary fresh air provided by a pressure ventilation system (up to 6 air changes/h); pressure and exhaust ventilation systems equipped with ventilation units supplying fresh air to and discharging contaminated air outside the working area (more than 10 air changes/h); complete air-conditioning system with laminar air flow (more than 15 air changes/h). The measurements were carried out during surgical procedures (general anaesthesia induced intravenously and maintained with inhaled N(2)O and sevofluran delivered through cuffed endotracheal tubes) with connected or disconnected air scavenging. Air was collected from the breathing zone of operating personnel continuously through the whole time of anaesthesia to Tedlar((R)) bags, and N(2)O concentrations in air samples were analyzed by adsorption gas chromatography/mass spectrometry. RESULTS: N(2)O levels in excess of the occupational exposure limit (OEL) value of 180mg/m(3) were registered in all ORs equipped with ventilation systems alone. The OEL value was exceeded several times in rooms with natural ventilation plus supplementary pressure ventilations and twice or less in those with pressure/exhaust ventilation systems or air conditioning. N(2)O levels below or within the OEL value were observed in rooms where the system of air conditioning or pressure/exhaust ventilation was combined with scavenging systems. Systems combining natural/pressure ventilation with scavenging were inadequate to maintain N(2)O concentration below the OEL value. CONCLUSION: Air conditioning and an efficient pressure/exhaust ventilation (above 12 air exchanges/h) together with efficient active scavenging systems are sufficient to sustain N(2)O exposure in ORs at levels below or within the OEL value of 180mg/m(3).  相似文献   
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Hepatitis B and C infections are responsible for significant burden of disease accounting for 1.3 million deaths globally. There is a lack of quality data on the burden of disease due to these infections. One approach to informing policy makers on trends in hepatitis B and C is through case reporting of diagnosed cases. Data on these cases can identify outbreaks of hepatitis and monitor trends in acute and chronic infection. The European Centers for Disease Control (ECDC) has developed standardized case definitions and a harmonized reporting framework. Two articles in this issue summarize the trends in hepatitis B and C infection in Europe. The results show considerable variability in reported cases across countries, reflecting in part differences in testing practices. Risk factor information highlights the continued importance of injecting drug use as a risk factor for hepatitis C infection. Hepatitis case reporting provides valuable information, and more complete reporting will improve the utility of the data. For a comprehensive epidemiologic assessment of the burden of hepatitis, case reporting should be complemented by other sources of data, such as serologic and behavioural surveys.  相似文献   
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