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91.
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This study aimed to identify the factors associated with timely (within four weeks) HCV RNA testing and timely (within six months) DAA initiation following HCV notification in the DAA era. We conducted a cohort study of people with an HCV notification in NSW, Australia. Notifications of positive HCV serology were linked to administrative datasets. Weights were applied to account for spontaneous clearance. Logistic regression analyses were performed. Among 5582 people with an HCV notification during 2016–2017, 3867 (69%) were tested for HCV RNA, including 2770 (50%) who received timely testing. Among an estimated 3925 people with chronic HCV infection, 2372 (60%) initiated DAA therapy, including 1370 (35%) who received timely treatment. Factors associated with timely HCV RNA testing included age (≥30 years), female sex, non-Aboriginal ethnicity, country of birth being Australia, and no history of drug dependence. Factors associated with timely treatment were age (≥30 years), male sex, non-Aboriginal ethnicity, country of birth being Australia, no history of drug dependence, and HCV/HIV co-infection. In the DAA era, 50% of people with an HCV notification did not receive timely HCV RNA testing. Most people with an HCV infection received therapy; however, DAA initiation was delayed among many.  相似文献   
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Smoking cessation after a cancer diagnosis can significantly improve a person’s prognosis, treatment efficacy and safety, and quality of life. In 2012, Cancer Care Ontario (now part of Ontario Health) introduced a Framework for Smoking Cessation, to be implemented for new ambulatory cancer patients at the province’s 14 Regional Cancer Centres (RCCs). Over time, the program has evolved to become more efficient, use data for robust performance management, and broaden its focus to include new patient populations and additional data collection. In 2017, the framework was revised from a 5As to a 3As brief intervention model, along with an opt-out approach to referrals. The revised model was based on emerging evidence, feedback from stakeholders, and an interim program evaluation. Results showed an initial increase in referrals to cessation services. Two indicators (tobacco use screening and acceptance of a referral) are routinely monitored as part of Ontario Health’s system-wide performance management approach, which has been identified as a key driver of change among RCCs. Due to the COVID-19 pandemic, many RCCs reported a decrease in these indicators. RCCs that were able to maintain a high level of smoking cessation activities during the pandemic offer valuable lessons, including the opportunity to swiftly leverage virtual care. Future directions for the program include capturing data on cessation outcomes and expanding the intervention to new populations. A focus on system recovery from COVID-19 will be paramount. Smoking cessation must remain a core element of high-quality cancer care, so that patients achieve the best possible health benefits from their treatments.  相似文献   
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Bone-related defects that cannot heal without significant surgical intervention represent a significant challenge in the orthopedic field. The use of implants for these critical-sized bone defects is being explored to address the limitations of autograft and allograft options. Three-dimensional cellular structures, or bone scaffolds, provide mechanical support and promote bone tissue formation by acting as a template for bone growth. Stress shielding in bones is the reduction in bone density caused by the difference in stiffness between the scaffold and the surrounding bone tissue. This study aimed to reduce the stress shielding and introduce a cellular metal structure to replace defected bone by designing and producing a numerically optimized bone scaffold with an elastic modulus of 15 GPa, which matches the human’s cortical bone modulus. Cubic cell and diagonal cell designs were explored. Strut and cell dimensions were numerically optimized to achieve the desired structural modulus. The resulting scaffold designs were produced from stainless steel using laser powder bed fusion (LPBF). Finite element analysis (FEA) models were validated through compression testing of the printed scaffold designs. The structural configuration of the scaffolds was characterized with scanning electron microscopy (SEM). Cellular struts were found to have minimal internal porosity and rough surfaces. Strut dimensions of the printed scaffolds were found to have variations with the optimized computer-aided design (CAD) models. The experimental results, as expected, were slightly less than FEA results due to structural relative density variations in the scaffolds. Failure of the structures was stretch-dominated for the cubic scaffold and bending-dominated for the diagonal scaffold. The torsional and bending stiffnesses were numerically evaluated and showed higher bending and torsional moduli for the diagonal scaffold. The study successfully contributed to minimizing stress shielding in bone tissue engineering. The study also produced an innovative metal cellular structure that can replace large bone segments anywhere in the human body.  相似文献   
96.
Delayed neurotoxic complications of chemical warfare agents (CWA), such as sulphur mustard (SM) and tabun, in human beings have not been reported in detail. We thus aimed to investigate possible neurotoxic complications of these agents in Iranian veterans 22–27 years after exposure. After co‐ordination with the veteran foundation and obtaining the approval of the medical research ethics committee, 43 Iranian veterans with late complications of CWA exposure during the Iran–Iraq conflict were studied after obtaining signed written informed consent. Demographic and clinical findings were recorded on pre‐designed forms. Neurological examination was performed by a neurologist. Routine biochemical tests were performed for all the patients. Electromyography (EMG), nerve conduction velocity (NCV) and electroencephalography (EEG) were carried out as clinically indicated. The majority of the patients (38) had been exposed to SM and only five patients to tabun. Hyperaesthesia was the most objective finding (72.1%). Fatigue (93%), paraesthesia (88.3%) and headache (83.7%) were the most common subjective findings in the patients. Sensory nerve impairments, including paraesthesia (88.3%), hyperaesthesia (72.1%) and hypoesthesia (11.6%), were the most common observed clinical complications. EMG and NCV were impaired in seven patients (16.3%) who were all SM‐exposed patients but did not show any significant correlation with organ complications. EEG was negative even in the seized patients. Cholesterol, LDL and triglyceride levels were significantly above the normal ranges. Late neurological complications of CWA, particularly SM poisoning, are considerable even after three decades of exposure and require medical attention.  相似文献   
97.
β-Carbolines (BCs) are considered to be endogenous toxins and have been proposed as possible causative candidates inducing Parkinson's disease (PD). However, there is controversy about the effect and also effective dose of these compounds in the etiology of PD. This study was designed to further examine the effect of norharman (NH), a BC which in mammalian brain occurs at high levels in the substantia nigra, on the development of Parkinsonism-like behaviors in rats. A small amount (4μl) of NH solution at 2 or 200ng/ml was unilaterally injected into either striatum or substantia nigra (SN) by stereotaxic surgery. The development of Parkinsonism was assessed by three conventional behavioral tests, compared to the effects of unilateral 6-hydroxydopamine (6-OHDA) - induced lesions in the nigrostriatal pathway. An apomorphine-induced rotational test revealed no Parkinsonism-like behavior in the NH treated groups. However, rats that received the high concentration of NH into their SN showed significant biased swings in the elevated body swing test. In a rotarod test, NH treated groups showed relatively weak motor performance and their learning patterns were close to that of the 6-OHDA treated rats. Considering that the rotational test is only valid in animals with severe Parkinsonism, but time spent on the rotating rod correlates inversely with severity of Parkinsonism, our results indicate that a single exposure to low amounts of NH is effective in producing moderate Parkinsonism-like behavioral symptoms, possibly through a neurotoxic effect of this agent on the SN dopaminergic neurons.  相似文献   
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We report the destructive adsorption of Diazinon pesticide by porous webs of activated carbon nanofibers containing Al2O3 and MgO nanoparticles. The results show that, the presence of Al2O3 and MgO nanoparticles in the activated carbon nanofibers increases the amount of destructively adsorbed Diazinon pesticide by activated carbon nanofibers. Moreover, type, amount, and specific surface area of metal oxide nanoparticles affect the adsorption rate as well as the total destructively adsorbed Diazinon. Liquid chromatography proved the degradation of Diazinon by chemical reaction with Al2O3 and MgO nanoparticles. Liquid chromatography–mass spectrometry showed that the main product of reaction between Diazinon and the metal oxides is 2-isopropyl-6-methyl-4-pyrimidinol with less toxicity than Diazinon.  相似文献   
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