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1.
The aim of this study was to investigate the test–retest (TRT) repeatability of various parametric quantification methods for [18F]Flortaucipir positron emission tomography (PET). We included eight subjects with dementia or mild cognitive impairment due to Alzheimer’s disease and six cognitively normal subjects. All underwent two 130-min dynamic [18F]Flortaucipir PET scans within 3 ± 1 weeks. Data were analyzed using reference region models receptor parametric mapping (RPM), simplified reference tissue method 2 (SRTM2) and reference logan (RLogan), as well as standardized uptake value ratios (SUVr, time intervals 40–60, 80–100 and 110–130 min post-injection) with cerebellar gray matter as reference region. We obtained distribution volume ratio or SUVr, first for all brain regions and then in three tau-specific regions-of-interest (ROIs). TRT repeatability (%) was defined as |retest–test|/(average (test + retest)) × 100. For all methods and across ROIs, TRT repeatability ranged from (median (IQR)) 0.84% (0.68–2.15) to 6.84% (2.99–11.50). TRT repeatability was good for all reference methods used, although semi-quantitative models (i.e. SUVr) performed marginally worse than quantitative models, for instance TRT repeatability of RPM: 1.98% (0.78–3.58) vs. SUVr80–100: 3.05% (1.28–5.52), p < 0.001. Furthermore, for SUVr80–100 and SUVr110–130, with higher average SUVr, more variation was observed. In conclusion, while TRT repeatability was good for all models used, quantitative methods performed slightly better than semi-quantitative methods.  相似文献   
2.
The clinical spectrum of postpartum thyroid disease   总被引:1,自引:0,他引:1  
The clinical and biochemical features of postpartum thyroid disease were analysed in 152 antithyroid peroxidase antibody-positive (anti TPO+ve) women and compared with 239 anti-TPO-ve age-matched control postpartum women. All were assessed monthly for up to 12 months postpartum. Seventy three anti-TPO+ve women developed post-partum thyroiditis (PPT): 19.2% hyperthyroid alone, 49.3% hypothyroid alone, and 31.5% characterized by hyper- followed by hypothyroidism. None of the antibody-negative women developed any thyroid dysfunction. A significant increase in many of eleven symptoms of hypothyroidism and some of eight symptoms of hyperthyroidism compared to control women was observed in all anti-TPO+ve women, independent of thyroid status. This was particularly seen in women who later developed PPT when they were euthyroid, but was also observed in euthyroid anti-TPO+ve women who showed no decline of thyroid function during the postpartum period. Although PPT is usually transient, this condition, and the euthyroid antibody-positive state, may be associated with significant symptomatology, including an increased incidence of minor to moderate depression. Early recognition of this syndrome by antenatal screening of thyroid antibodies may contribute to improved management of women during the postpartum period.   相似文献   
3.
Nearly all countries in the world today are burdened with malnutrition, manifesting as undernutrition, micronutrient deficiencies, and/or overweight and obesity. Despite some progress, efforts to alleviate malnutrition are hampered by a shortage in number, skills, and geographic coverage, of a workforce for nutrition. Here, we report the findings of the Castel Gandolfo workshop, a convening of experts from diverse fields in March 2014 to consider how to develop the capacity of a global cadre of nutrition professionals for the post-2015 development era. Workshop participants identified several requirements for developing a workforce for nutrition, including an ability to work as part of a multisectoral team; communication, advocacy, and leadership skills to engage decision makers; and a set of technical skills to address future challenges for nutrition. Other opportunities were highlighted that could immediately contribute to capacity development, including the creation of a consortium to link global North and South universities, online training modules for middle managers, and practical, hands-on experiences for frontline nutrition workers. Institutional and organizational support is needed to enable workshop recommendations on education and training to be effectively implemented and sustained. The findings from the Castel Gandolfo workshop can contribute to the delivery of successful nutrition-relevant actions in the face of mounting external pressures and informing and attaining the forthcoming Sustainable Development Goals.  相似文献   
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5.
An outbreak of Tunga Penetrans (Jigger Flea) infestation affecting a number of villages near to a Central Hospital in Malawi is described. Due to the large number of affected individuals, high parasitic load, and extended duration of infection an alternative to the recommended approach of surgical removal of the flea was required. Benzyl benzoate paint and liquid paraffin had been used in local Primary Healthcare settings previously and topical treatment with antiparasitic agents has been advocated in the literature, particularly for severe infestation. Benzyl benzoate and liquid paraffin were applied topically to four adults with numerous jigger flea burrows, and their progress assessed regularly. After completion of 7 days of treatment patients noted that fleas were dislodging spontaneously, and that embedded parasites had not increased in size to the same extent that untreated fleas had in previous infestations. Following confirmation of the viability of its implementation in a resource-poor setting, this treatment regimen has subsequently been adopted by the local branch of the District Health Office for distribution to infected communities.  相似文献   
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7.
目的:临床局部辐射条件下会造成非辐射区域组织及细胞功能损害,最为突出的是对造血功能的影响。实验建立60Coγ射线左半身辐射动物模型,观察局部电离辐射对其非辐射区域骨髓巨核细胞的影响。方法:实验于2003-10/2005-03在解放军第三军医大学辐照中心和全军复合伤研究所完成。①实验动物:6~8周龄SPF级雄性昆明小鼠180只,随机数字表法分为正常对照组、全身辐射组、左半身辐射组、全身屏蔽辐射组,45只/组。②实验方法:全身辐射组小鼠固定于辐射架内;左半身辐射组小鼠麻醉后固定体位,用铅砖屏蔽右半身;全身屏蔽辐射组小鼠麻醉固定体位,用铅砖屏蔽全身。以60Coγ射线一次性辐射,剂量率68.46cGy/min。正常对照组不作任何干预。③实验评估:辐射后不同时相检测小鼠血清丙二醛含量及超氧化物歧化酶活性变化,计数外周血血小板,检测骨髓巨核祖细胞集落形成单位,观察骨髓组织病理改变及CD41a、CD61的表达。结果:全身辐射组第8天死亡2只,第9天死亡4只,其余各组无脱失。①外周血血小板计数:辐射后第2,7天,左半身辐射组外周血血小板数量显著低于正常对照组(P<0.01),但高于全身辐射组(P<0.01)。②血清丙二醛含量及超氧化物歧化酶活性变化:辐射后第2,9天,左半身辐射组血清丙二醛含量显著高于正常对照组(P<0.01),低于全身辐射组(P<0.01);血清超氧化物歧化酶活性显著低于正常对照组(P<0.01),高于全身辐射组(P<0.01)。③骨髓巨核祖细胞集落形成单位的变化:与正常对照组比较,辐射后6h左半身辐射组非辐射侧的巨核祖细胞集落形成单位显著降低(P<0.01),高于全身辐射组及左半身辐射组(P<0.01)。④骨髓组织病理改变:正常对照组有核细胞比例较高,分布均匀,并见多量散在分布的细胞龛;辐射2d后,左半身辐射组非辐射侧骨髓有核细胞较正常对照组减少,但好于全身辐射组、左半身辐射组。⑤骨髓CD41a及CD61表达的变化:辐射后2d与正常对照组比较,左半身辐射组非辐射侧骨髓CD41a及CD61阳性细胞数和相对荧光强度均显著降低(P<0.01),但高于全身辐射组、左半身辐射组(P<0.01)。结论:局部电离辐射作用后,可导致小鼠非辐射区域骨髓巨核细胞增殖能力降低,血小板减少,产生功能障碍。氧自由基激活可能参与了该损伤过程。  相似文献   
8.
目的:认识影响大学生骨密度的各种生活因子,以便指导大学生提高骨密度,预防骨质疏松症的发生。方法:于2005-07/08选择延边大学医学院在校生自愿者638人,其中朝鲜族男生130人,朝鲜族女生110人,汉族男生196人,汉族女生202人。采用问卷调查方式,调查内容包括被调查者的自然状况、饮食、运动情况及其他与骨密度有关的生活方式。同时对调查对象进行右足跟骨骨密度测定。综合骨评价值=透过指数×超声波传导速度。结果:纳入受试对象638人,均进入结果分析。①汉族男生的综合骨评价值明显低于朝鲜族男生(分别为3.0±0.4,3.2±0.4,P<0.05),女生不存在民族差异。②男生的生活方式与骨密度的关系:注意平衡膳食及摄取充足的豆制品有利于骨密度提高(t=10.693,P<0.01;t=2.483,P<0.05);进行定期的运动(足球、篮球、排球、网球等球类运动和使用健身器)以及中学时期除了上体育课之外进行过体育运动能明显提高骨密度(t=10.693,P<0.01;t=1.998,P<0.05);有骨折史的学生骨密度明显低于无骨折史的学生(t=2.028,P<0.05)。③女生的生活方式与骨密度的关系:经常不吃早餐的学生骨密度低于按时吃早餐的学生(t=6.600,P<0.01);注意均衡饮食和进行定期运动的学生骨密度明显高于不注意均衡饮食和不做定期运动的学生(t=4.149,P<0.01;t=2.992,P<0.01)。③女生中也表现出有骨折史的学生骨密度显著低于无骨折史的学生(t=1.965,P<0.05)。结论:影响大学生骨密度的因素有骨折史、定期运动、均衡饮食、豆制品摄取。  相似文献   
9.
We describe a young man who developed extensive hypothalamicdysfunction including diabetes insipidus, adipsia, hyperprolactinaemia,and poikiliothermia together with central sleep apnoea followingexposure to toluene.  相似文献   
10.
Occupational violence (OV) is a daily risk for ED staff. It contributes to staff stress, sick leave, turn‐over and burn‐out, and limits the capacity of staff to provide unimpeded quality care to patients and their families. Many factors contribute to incidents of OV; however, early detection of such risk factors could pre‐empt incidences of OV during ED episodes of care. A five‐stage methodological framework for scoping reviews was used to identify, summarise and synthesise OV risk factors from five key databases. A validated tool was used to appraise the quality of included studies. Independent evaluation by the reviewers was used throughout. Patient factors were extracted and described from 24 methodologically and geographically diverse papers. Methodological quality for these studies varied from moderate to high. A total of 34 OV risk factors were identified. Although there was variation in, and differences between, staff‐perceived and objective (documented) OV risk factors, patient risk factors can be categorised into three main groups: clinical presentation, behaviours and past history. Five existing ED OV risk assessment tools were identified, with limited supporting evidence for each. The results support the development of a reliable and validated OV risk assessment tool to be initiated at triage.  相似文献   
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