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ObjectiveIn cases of head and neck cancer treated with intra-arterial chemotherapy, no objective indices are available for determining the distribution of anticancer drugs administered to multiple arteries. To establish such indices, noninvasive measurements of drug concentrations are required in the arterial perfusion area of each artery. In MRI, changes in 1/T1 (Δ1/T1) are correlated with the contrast agent concentration. We focused on these properties and investigated whether it is possible to estimate anticancer drug concentrations within tissue based on Δ1/T1.MethodsWe employed the fast spin echo (FSE) sequence to determine optimum imaging parameters using a phantom. Subsequently, contrast agent was administered via the lingual and external carotid arteries for seven cases of tongue cancer. Δ1/T1 were then measured in tumor and nontumor tissues. The results of this study were compared with those of a previous study in which intratumor concentrations of anticancer agent were measured in excised specimens.ResultsThe optimum imaging parameters for the FSE was two repetition times (TR, 500 and 1000 ms). When compared with the external carotid artery administration, the lingual artery administration of contrast agent resulted in significantly higher Δ1/T1 in both tumor and nontumor tissues (2.13 and 2.62 times, respectively). The multiplying factor for the nontumor tissue and high homogeneity of the contrast agent concentration were reasonably consistent with the results of the previous study.ConclusionThis method can be applied to estimating intratissue concentrations of intra-arterially administered anticancer drugs, thus possibly providing useful information in determining the distribution of anticancer drugs.  相似文献   
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Modified-release opioids are often prescribed for the management of moderate to severe acute pain following total hip and knee arthroplasty, despite recommendations against their use due to increasing concerns regarding harm. The primary objective of this multicentre study was to examine the impact of modified-release opioid use on the incidence of opioid-related adverse events compared with immediate-release opioid use, among adult inpatients following total hip or knee arthroplasty. Data for total hip and knee arthroplasty inpatients receiving an opioid analgesic for postoperative analgesia during hospitalisation were collected from electronic medical records of three tertiary metropolitan hospitals in Australia. The primary outcome was the incidence of opioid-related adverse events during hospital admission. Patients who received modified with or without immediate-release opioids were matched to those receiving immediate-release opioids only (1:1) using nearest neighbour propensity score matching with patient and clinical characteristics as covariates. This included total opioid dose received. In the matched cohorts, patients given modified-release opioids (n = 347) experienced a higher incidence of opioid-related adverse events overall, compared with those given immediate-release opioids only (20.5%, 71/347 vs. 12.7%, 44/347; difference in proportions 7.8% [95%CI 2.3–13.3%]). Modified-release opioid use was associated with an increased risk of harm when used for acute pain during hospitalisation after total hip or knee arthroplasty.  相似文献   
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崔娜  王小刚  董磊 《西部医学》2022,34(8):1230-1234
目的 探讨血管内超声虚拟组织学成像(VH-IVUS)与实时剪切弹性成像技术(SWE)评估颈动脉斑块稳定性及脑梗死的价值。方法 选取2018年12月~2020年12月在中国人民解放军联勤保障部队第960医院就诊的颈动脉粥样硬化斑块患者130例(201个斑块),分析不同性质斑块VH-IVUS评分及平均杨氏模量差异,及评估稳定性斑块的价值。130例颈动脉粥样硬化斑块患者近期发生脑梗死53例(脑梗死组),无脑梗死77例(无脑梗死组),比较两组甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)、VH-IVU评分及平均杨氏模量水平,同时分析VH-IVUS评分及平均杨氏模量评估脑梗死的价值。结果 易损性斑块VH-IVUS评分高于稳定性斑块(P<0.05),而平均杨氏模量低于稳定性斑块(P<0.05);VH-IVUS评分、平均杨氏模量评估稳定性斑块的ROC曲线下面积分别为0.789和0.875。脑梗死组TG、LDL-C明显高于无脑梗死组(P<0.05),而HDL-C明显低于无脑梗死组(P<0.05);脑梗死组斑块VH-IVUS评分明显高于无脑梗死组(P<0.05),而平均杨氏模量明显低于无脑梗死组(P<0.05);VH-IVUS评分、平均杨氏模量评估脑梗死的ROC曲线下面积分别为0.658和0.822。结论 VH-IVUS与SWE技术评估颈动脉斑块稳定性及脑梗死方面有较好的价值,其中SWE评估价值较高。  相似文献   
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目的了解临床护士工作自主性与行为目标达成度现状,并探讨两者的相关性,为提高护士行为目标达成度提供参考。方法以方便抽样法选取临床护士286名,采用工作自主性量表、护士行为目标达成度量表进行调查。结果临床护士工作自主性得分为(5.16±1.45)分,行为目标达成度得分为(4.22±0.69)分;工作自主性与行为目标达成度呈正相关(P<0.01);多元回归分析结果显示,护理层级、婚姻状况和工作自主性是护士行为目标达成度的主要影响因素(P<0.05,P<0.01)。结论临床护士的工作自主性和行为目标达成度均处于较高水平,临床护士工作自主性越高,其行为目标达成度越好。护理管理者应重视培养护士的工作自主性,挖掘护士的工作潜能,提高护士行为目标达成度,提升优质护理服务质量。  相似文献   
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International Ophthalmology - To report a series of patients who developed neurotrophic keratopathy following scleral fixation of intraocular lenses. Retrospective case series of patients...  相似文献   
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Pharmaceutical Chemistry Journal - Metformin hydrochloride is widely used to treat diabetes mellitus. This review presents its physical and chemical properties and discusses methods of analysis...  相似文献   
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In the last decade, the development of new radiopharmaceuticals for the imaging and therapy of prostate cancer has been a highly active and important area of research, especially focusing on the prostate-specific membrane antigen (PSMA), an antigen which is upregulated in prostate, as well as in other tumor cells. A large variety of PSMA ligands have been radiolabeled, to date. Among the various derivatives, PSMA-617 resulted to be one of the most interesting in terms of interaction with the antigen and clinical properties, and its lutetium-177 labeled version has recently been approved by regulatory agencies for therapeutic purposes. For this reasons, the radiolabeling with fluorine-18 of a PSMA-617 derivative might be of interest. Beside other methodologies to radiolabel macromolecules with fluorine-18, the “click-chemistry” approach resulted to be very useful, and the copper-catalyzed azide-alkyne cycloaddition (CuAAC) is considered one of most efficient and reliable. This paper proposes the synthesis of a suitable precursor for the radiolabeling with fluorine-18 of a new PSMA-617 derivative. The whole radiosynthetic procedure has been fully automated, and the final product, which proved to be stable in plasma, has been obtained with radiochemical yield and purity suitable for subsequent preclinical studies.  相似文献   
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