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AIM:To evaluate the efficacy of reduced cathartic bowel preparation with 2 L polyethylene glycol(PEG)-4000 electrolyte solution and 10 mg bisacodyl enteric-coated tablets for computed tomographic colonography(CTC).METHODS:Sixty subjects who gave informed consent were randomly assigned to study group A,study group B or the control group.On the day prior to CTC,subjects in study group A were given 20 mL 40% wt/vol barium sulfate suspension before 3 mealtimes,60 mL 60% diatrizoate meglumine diluted in 250 mL water after supper,and 10 mg bisacodyl enteric-coated tablets 1 h before oral administration of 2 L PEG-4000 electrolyte solution.Subjects in study group B were treated identically to those in study group A,with the exception of bisacodyl which was given 1 h after oral PEG-4000.Subjects in the control group were managed using the same strategy as the subjects in study group A,but without administration of bisacodyl.Residual stool and fluid scores,the attenuation value of residual fluid,and discomfort during bowel preparation in the three groups were analyzed statistically.RESULTS:The mean scores for residual stool and fluid in study group A were lower than those in study group B,but the differences were not statistically significant.Subjects in study group A showed greater stool and fluid cleansing ability than the subjects in study group B.The mean scores for residual stool and fluid in study groups A and B were lower than those in the control group,and were significantly different.There was no significant difference in the mean attenuation value of residual fluid between study group A,study group B and the control group.The total discomfort index during bowel preparation was 46,45 and 45 in the three groups,respectively,with no significant difference.CONCLUSION:Administration of 10 mg bisacodyl enteric-coated tablets prior to or after oral administration of 2 L PEG-4000 electrolyte solution enhances stool and fluid cleansing ability,and has no impact on the attenuation value of residual fluid or the discomfor  相似文献   
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Congenital microphthalmia is a rare phenotype characterized by eye growth retardation. Due to the lack of eyeball stimulation, children suffering from congenital microphthalmia always have bony orbital maldevelopment, which leads to facial asymmetry. In the present study, a structured light 3D scanning system was used as a novel method to measure the three-dimensional periorbital asymmetry in children with congenital microphthalmia.Children with unilateral congenital microphthalmia of 0–6 years old were enrolled in the present study. All participants underwent an ultrasound scan to measure the axial length, and accepted the structured light 3D scanning system for their periorbital appearance. The degree of periorbital asymmetry was evaluated using 17 facial landmarks within a three-dimensional cartesian coordinate system (the X-axis represented the horizontal direction, the Y-axis represented the vertical direction, and the Z-axis represented the sagittal direction). Paired student t-test and ANOVA were used in the present study. A three-dimensional periorbital topography was also established to further illustrate the periorbital asymmetry.A total of 67 children were recruited, which included 31 boys and 34 girls. The axial length on the affected side (12.28 ± 3.35 mm) was generally smaller than that on the unaffected side (20.54 ± 1.65 mm, P < 0.001). When grouped by age, the periorbital asymmetry mainly manifested in the Y-axis and Z-axis directions. The unaffected side had a higher orbitale superior (5.09 ± 0.35 vs. 3.02 ± 0.30, P < 0.001) and a lower orbitale inferior (?19.52 ± 0.51 vs. ?16.90 ± 0.53, P < 0.001) in 0–1 year old group. Same performances were also found in the 1–3 and 3–6 age groups. When grouped according to the proportion of axial length on the bilateral sides, seven of the 12 Y-values and all 12 Z-values had statistical differences.The structured Light 3D scanning system may serve as a beneficial complementary tool for computed tomography, in order to better understand the periorbital deformities caused by congenital microphthalmia.  相似文献   
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目的:分析甲醛染毒对体外培养的人Ⅱ型肺泡上皮细胞(A549)内8-羟基鸟嘌呤脱氧核苷(8-oxo-dG)水平、DNA5-甲基胞嘧啶(5-mC)含量的影响及其时间-效应和剂量-效应关系,探讨甲醛所致的细胞DNA氧化与DNA甲基化的关联性。方法:用5~20μmol/L甲醛作用于A549细胞,用高压液相色谱串联电化学检测技术分析细胞DNA8-oxo-dG水平,用免疫荧光和高效毛细管电泳法检测细胞全基因组DNA5-mC含量改变。 结果:甲醛染毒提高了细胞8-oxo-dG水平,但是降低了细胞的DNA5-mC含量。甲醛致细胞DNA氧化与DNA甲基化呈现不同特点,A549细胞暴露于20 μmol/L 甲醛后,DNA氧化水平在1周甚至更早时间就已显著增高,而相同条件下DNA 甲基化水平的改变需要6周以上的时间,DNA 甲基化的改变滞后于DNA氧化。 A549细胞经5~20μmol/L甲醛染毒8周后,DNA氧化水平与甲醛剂量呈正相关关系,而同样条件下DNA甲基化水平与甲醛剂量呈负相关关系。 结论:甲醛染毒可提高DNA氧化水平,降低细胞DNA甲基化水平。在甲醛的毒作用效应中,细胞DNA氧化损伤可能是早于其DNA甲基化的一个重要分子事件。  相似文献   
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Since segmentation labeling is usually time-consuming and annotating medical images requires professional expertise, it is laborious to obtain a large-scale, high-quality annotated segmentation dataset. We propose a novel weakly- and semi-supervised framework named SOUSA (Segmentation Only Uses Sparse Annotations), aiming at learning from a small set of sparse annotated data and a large amount of unlabeled data. The proposed framework contains a teacher model and a student model. The student model is weakly supervised by scribbles and a Geodesic distance map derived from scribbles. Meanwhile, a large amount of unlabeled data with various perturbations are fed to student and teacher models. The consistency of their output predictions is imposed by Mean Square Error (MSE) loss and a carefully designed Multi-angle Projection Reconstruction (MPR) loss. Extensive experiments are conducted to demonstrate the robustness and generalization ability of our proposed method. Results show that our method outperforms weakly- and semi-supervised state-of-the-art methods on multiple datasets. Furthermore, our method achieves a competitive performance with some fully supervised methods with dense annotation when the size of the dataset is limited.  相似文献   
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 报告皮下型分叶状毛细血管瘤1例。患者男,19岁,左手臂结节伴疼痛3月余。皮肤专科检查:左手臂约上1/3处见一类圆形暗红色皮下结节,稍隆起于皮面,大小约12 mm×10 mm,表面覆有少许细薄白色鳞屑,未见破溃、糜烂,边界较清,活动度欠佳,质地硬韧,按压痛阳性。皮损组织病理:真皮内大量增生的毛细血管密集排列,由纤维性间隔分隔,形成小叶状结构,无包膜,界限清楚。血管内皮细胞增生,未见核异形及病理性核分裂像。诊断:皮下型分叶状毛细血管瘤。治疗:手术切除。随访4个月未见复发。  相似文献   
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Clinical and Experimental Medicine - A biochemiluminescent assay of influenza diagnosis is presented. The assay diagnoses influenza based on detection of the influenza viral neuraminidase activity....  相似文献   
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正PM_(2.5) are fine inhalable particles with diameters that are generally 2.5 micrometers and smaller and are characterized by a small particle size, a large surface area, and a strong toxin absorption ability~([1-3]).PM_(2.5) contains heavy metals and organic pollutants that are harmful to human health and exert  相似文献   
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