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1.
阿尔茨海默病是一种进行性且不可逆转的神经系统疾病,由于视网膜和中枢神经系统有相似的胚胎起源和生理特征,眼科检查可提供简单无创的诊断方法。光学相干断层扫描技术(OCT)能够精确地测量视网膜各个组织层面的厚度,以评估视网膜的退行性改变,光学相干断层扫描血管成像(OCTA)可以提供高分辨率三维成像,从而更直观地检测视网膜血管的变化,间接地反映脑神经元和血管的病理特征。就OCT测量视网膜厚度及OCTA测量视网膜血流变化在阿尔茨海默病诊断中的研究进展进行综述。 相似文献
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《Radiography》2022,28(3):663-667
IntroductionAnti-scatter grids efficiently reduce scatter radiation from reaching the imaging receptor, enhancing image quality; however, the patient radiation dose increases in the process. There is disagreement regarding the thickness thresholds for which anti-scatter grids are beneficial. This study aims to establish a thickness threshold for the use of anti-scatter grids to optimise adult knee radiography.MethodsThe study consisted of two phases. In Phase 1 phantom knee radiographs were acquired at varying thicknesses (10–16 cm) and tube voltages (60–80 kV). For each thickness and tube voltage, images with and without an anti-scatter grid were obtained. In Phase 2, two radiologists and three radiographers, evaluated the image quality of these images. Visual Grading Analysis (VGA) scores were analysed using Visual Grading Characteristics (VGC) based on the visualisation of five anatomic criteria.ResultsThe average DAP decreased by 72.1% and mAs by 73.1% when removing the anti-scatter grid. The VGC revealed that overall images taken with an anti-scatter grid have better image quality (AUC ≥0.5 for all comparisons). However, the anti-scatter grids could be removed for thicknesses 10, 12 and 14 cm in conjunction with using 80 kVp,.ConclusionAnti-scatter grids can be removed when imaging adult knees between 10 and 12 cm using any kVp setting since the radiation dose is reduced without significantly affecting image quality. For thicknesses >12 cm, the use of anti-scatter grids significantly improves image quality; however, the radiation dose to the patient is increased. The exception is at 14 cm used with 80 kVp, where changes in image quality were insignificant.Implications for practiceOptimisation by removing anti-scatter grids in adult knee radiography seems beneficial below 12 cm thickness with any kVp value. Since the average knee thickness ranges between 10 and 13 cm, anti-scatter grid can be removed for most patients. Nevertheless, further studies are recommended to test if this phantom-based threshold applies to human subjects. 相似文献
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笔者根据现代临床子宫内膜的病理演变过程结合中医“异病同治”理念,提出“子宫内膜功能亢进性疾病”概念,涵盖5种常见的子宫内膜疾病:无排卵性异常子宫出血(Abnormal Uterine Bleeding Ovulatory dysfunction,AUB-O),子宫内膜息肉(Endometrial Polyp,EP),子宫内膜异位症(Endometriosis,EMs),子宫腺肌病(Adenomyosis,AM),子宫内膜癌(Endometrial Carcinoma,EC)。基于文献的汇总,分析得到此类疾病的子宫内膜病理演变与中医病因病机的关联性,为寻找关键通路、创新性治疗此类疾病提供了重要的参考方向,对深化中医妇科学常见疾病的共性病因病机提供了理论依据和探索思路。 相似文献
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《Obesity research & clinical practice》2022,16(1):44-49
BackgroundPre-pregnancy obesity is a well-recognized risk factor for gestational diabetes mellitus (GDM). There is a continuity of obesity from childhood to adolescence and then adulthood. However, it is unknown whether early childhood obesity predicts GDM.MethodsWe investigated the prospective association of childhood triceps skinfold thickness and body mass index (BMI) with GDM risk among women from the Mater-University of Queensland Study of Pregnancy (MUSP), a multigenerational cohort study. A multiple logistic regression model was applied to estimate the odds of experiencing GDM by childhood skinfold thickness and BMI.ResultsOut of 552 women in the study for whom data were available on triceps skinfold thickness and BMI at average age 5 (range 3–7) years old, 52 (9.42%) developed GDM by average age 30 (range 28–33) years. We found that the risk of developing GDM was greater among women who had greater skinfold thickness but not greater BMI at age 5 years. Women who were classified as overweight or obese based on skinfold thickness at age 5 years had an increased odds ratio of GDM compared to women who had normal skinfold thickness. This association remained significant after adjustment for the potential confounders (OR 2.74; 95% confidence interval = 1.28–5.86).ConclusionThe risk of developing GDM was associated with higher skinfold thickness at age 5 years. 相似文献
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目的 开发并评估一种用于预测子宫内膜病变患者内膜病理类型的临床模型;方法 选取2019年11月至2021年11月因妇科B超发现子宫内膜病变并于山东中医药大学附属医院行宫腔镜下内膜活检的患者,结合其病史与最小绝对收缩和选择算子法(Least absolute shrinkage and selection operator,LASSO)筛选影响内膜病变的独立危险因素,列线图(nomogram)函数建立列线图模型,采用ROC曲线下方的面积大小(Area Under Curve, AUC)、C指数(C-index)、拟合优度(Hosmer-Lemeshow)检验、自举法(bootstrap)评估及验证模型,依据列线图对纳入患者进行风险赋分,绘制ROC曲线获取风险评分的截断值,从而划分高低风险的人群;结果 阴道流血、绝经、无流产史、并发高血压、B超内膜厚度增厚、内膜回声不正常,中医证型为虚实夹杂证是发生子宫内膜癌及癌前病变的独立危险因素,评估模型所得AUC值与C-index均>0.9,Hosmer-Lemeshow检验显示P>0.05,bootstrap内部验证法所得C-index亦高于0.9,均说明模型准确度、区分度及可信度良好,当患者的风险评分总和≥177分时,属于高风险人群;结论 本模型可以预测B超提示子宫内膜病变患者的内膜病理类型为癌前或恶变型的概率并识别高风险人群。 相似文献
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《Taiwanese journal of obstetrics & gynecology》2022,61(6):1082-1085
ObjectiveWe report a low-grade endometrial stromal sarcoma (ESS) with a novel CDKN1A-JAZF1 fusion gene arising from abdominal wall endometrioma.Case reportA 40-year-old woman presented with a 5.5-cm abdominal wall mass juxtaposed to the postoperative scar of two cesarean sections. Histologically, the tumor exhibited obvious tongue-like protrusions into the surrounding tissue, showed spindle cells with multinodular growth pattern that occasionally rotate around small arteries. Immunohistochemically, the tumor cells were positive for CD10, estrogen receptor (ER), progesterone receptor (PR), negatively stained for smooth muscle actin (SMA), CD117, CyclinD1. In addition, a previously undescribed gene fusion between CDNK1A 5′ end of exon 1(NM_000389.5) and JAZF1 3′ end of exon 5 (NM_175,061,3) was reported in this case.ConclusionThis report of ESS suggesting that rapidly growing abdominal wall masses without menstruation-related should be promptly evaluated and treated aggressively. In addition, we have expanded the molecular landscape of low-grade ESS. 相似文献