Recognition performance and perceived quality of video enhanced for the visually impaired

Subjects with central field loss (CFL) individually selected enhancement parameters to improve visibility of static video images. The effect of enhancement on performance and on perceived quality of motion video was assessed. Performance, e.g. recognition of visual details, was assessed by having subjects answer questions regarding visual information contained in the video motion segments that were enhanced using the individually-selected parameters. Enhancement did not improve subject performance on questions about video content. This result might be due to a ceiling effect limitation of the performance assessment method. In a second procedure, subjects' continuous perceptions of quality (using an adjective-based rating scale) were made while the enhancement parameters were abruptly switched among multiple values; these included the individually-selected enhancements, as well as unenhanced, over-enhanced, and degraded segments. The results indicate that adaptive enhancement (individually-tuned using a static image) adds significantly to perceived image quality when viewing motion video. Subjects who selected stronger contrast enhancement also perceived the enhancement to provide a larger benefit in image quality.     

浅谈电子文档的原始性和真实性及法律证据作用

该文针对电子文件或档案的原始性真实性与电子档案的法律证据作用,参考了最新的研究结果,并提出了自己的思考,逐步探讨了它们的涵义及关系.     

低密度及氧化低密度脂蛋白对内皮细胞分泌肾上腺髓质素的影响

目的探讨低密度及氧化低密度脂蛋白对内皮细胞分泌肾上腺髓质素(ADM)的影响.方法利用培养的内皮细胞株ECV-304细胞,分别与不同浓度的低密度(50 100mg/L)、氧化低密度脂蛋白(50 100mg/L)及低密度脂蛋白(50 mg/L) 氧化低密度脂蛋白(50 mg/L)进行孵育,24 h后分别收集培养上清及细胞,用放免分析检测上清及细胞内肾上腺髓质素的含量.结果低密度脂蛋白对肾上腺髓质素的分泌无影响,而氧化型低密度脂蛋白能明显刺激ADM的分泌,二者合用的作用接近于100mg/L的OX-LDL.结论OX-LDL可能具有氧化LDL使其成为OX-LDL的作用,ADM的分泌可能是对细胞损伤的一种反应.     

Transcatheter closure of the patent arterial duct using the Flipper coil in a premature infant weighing 1,400 g: a case report.

A symptomatic 1,400 g premature triplet underwent successful transcatheter coil embolization of patent arterial duct using the umbilical artery. One 3 mm x 3 cm Flipper coil was used with no angiographic residual shunt. To the best of our knowledge, this is one of the smallest preterm infants to undergo this transcatheter procedure.     

Early rapid weight gain and current overweight in relation to asthma in adolescents born with very low birth weight

Early catch-up growth and subsequent overweight are suggested to be associated with later cardiovascular diseases and later type II diabetes. However, the impact of early catch-up growth and childhood overweight on the development of asthma has been less studied, particularly in children born with very low birth weight (VLBW). A birth cohort of 74 VLBW children (birth weight < or = 1500 g) was followed from birth and investigated on asthma at 12 yr of age. Early rapid weight gain was in one way defined as an increase of weight > or =1 standard deviation score (SDS) at 6 months of corrected postnatal age. Current overweight was defined by body mass index (BMI) exceeding 21.2 and 21.7 kg/m(2), respectively, for boys and girls at 12 yr of age. Current asthma was diagnosed by a pediatrician, according to asthma ever in combination with a positive response to hypertonic saline bronchial provocation test and/or wheeze at physical examination at 12 yr old. Being overweight at 12 yr of age was associated with an increased risk for current asthma in the VLBW children [crude odds ratio (OR): 5.5, 95% confidence interval (CI): 1.3-22.2]. After adjustment for early weight gain and neonatal risk, the OR of overweight increased nearly three times (adjusted OR: 15.3, 95% CI: 2.5-90.6). Early rapid weight gain seemed to be inversely associated with current asthma (adjusted OR: 0.49 for an increase of weight equal to 1 SDS, 95% CI: 0.23-1.02, p = 0.06). In addition, early rapid weight gain was inversely associated with the magnitude of bronchial responsiveness at 12 yr (coefficient -1.15, p < 0.01). There was a strong and positive association between overweight and asthma at 12 yr of age in the VLBW children. This strong association had been reduced by early rapid weight gain, possibly via the reduction of bronchial responsiveness.     

安徽省学生近20年常见病患病情况分析

目的了解安徽省学生视力低下、龋齿、贫血的患病状况及变化趋势,为开展学生常见病防治工作提供参考。方法对1985,1995,2000,2005年4个不同时期安徽省学生体质健康调研资料7～22岁学生视力低下、龋齿、贫血等常见病的患病状况进行分析。结果20a间,学生贫血患病率明显下降,从1985年的55.5%下降到2005年的5.3%;龋患率1985年至2000年明显上升,从32.1%上升到42.6%,2000年以后呈下降趋势,达18.8%;近视率逐年上升并居高不下,从1985年的23.0%上升到2005年的55.2%,尤其是高中生和大学生,高达70%～80%。结论通过开展学生常见病防治工作,学生贫血患病率和龋患率明显下降,但学生近视率逐年上升并居高不下,应引起有关部门的重视。     

Growth, bone maturation and pubertal development in children with the EMG-syndrome

In 7 patients (5 girls, 2 boys) with the EMG or Wiedemann-Beckwith syndrome, statural growth, bone age (BA), weight and pubertal development were studied longitudinally. Height was above the 90th percentile (%) for chronological age (CA) after age 2 years, reaching an average of 2.5 SD above the mean at or after puberty. Adult or attained height also exceeded significantly (P<0.015) parental (genetic) target height by 13.2 cm on the average. In one girl, adult height prognosis (190 cm) could be reduced to an adult height of 183 cm by high-dose estrogen treatment. In most children, growth velocity remained above the 90th % up to 4–6 years of age and normalized thereafter. In all patients studied, bone age was markedly advanced and particularly so during the first 4 years after birth. Weight was above the 90th–97th % during infancy and early childhood and remained there, appropriate or slightly subnormal for height, until adulthood, except for 3 girls who reached and maintained the 50th % during or after puberty. Spontaneous pubertal development occurred within normal limits for CA and around the 50th % for BA. Except for the marked bone age acceleration, the reason for the increased statural growth and adult height in patients with the EMG syndrome is still unknown.     

Adrenocortical responsiveness in neonates weaned from the ventilator with dexamethasone

Adrenocortical responsiveness was assessed in eight very low birthweight neonates who had bronchopulmonary dysplasia and had been weaned from mechanical ventilation using dexamethasone. Three of the eight infants did not respond to ACTH stimulation during the first week after cessation of dexamethasone, but all three responded normally when retested at least 1 month later. The present authors have thus demonstrated that some infants have at least temporary adrenocortical unresponsiveness after prolonged courses of glucocorticoid therapy, and suggest that adrenocortical function should be assessed in all infants who are weaned from mechanical ventilation using dexamethasone.     

对儿童X线体检中减少照射剂量的探讨

目的:探讨儿童在X线体检中减少照射剂量的方法。方法:应用东芝500mA遥控X线机、FJ-427型热释光剂量仪等设备,对100名3~5岁儿童体检时,随机分成两个对照组、每组50名,分别接受胸透或平片检查,对检查测得数据均进行统计学处理。结果:胸透时胸部接受的照射剂量是平片的22倍多,其它部位接受的X线散射剂量平均值之比亦在20~30倍之间。结论:在儿童X线体检中应采用常规胸片替代胸透,可以有效地降低其辐射危害。     

Homocysteinylation of low-density lipoproteins (LDL) from subjects with Type 1 diabetes: effect on oxidative damage of human endothelial cells.

BACKGROUND: Homocysteine (Hcy) is an independent risk factor for cardiovascular disease (CVD). Individuals with Type 1 and Type 2 diabetes are more susceptible to the effects of homocysteine than non-diabetic subjects. The interaction between homocysteine-thiolactone (Hcy-thiolactone), a reactive product of Hcy, and low-density lipoproteins (LDL) induces the formation of homocystamide-LDL adducts (Hcy-LDL) and it has been suggested that homocysteinylation could increase atherogenicity of lipoproteins. AIM: The aim of the study was to compare the effect of in vitro homocysteinylation of LDL isolated from healthy control subjects (C-LDL) and from Type 1 diabetic patients (DM-LDL) and to investigate the effect of homocysteinylated LDL (Hcy-C-LDL and Hcy-DM-LDL) on peroxynitrite production of endothelial cells. METHODS: The in vitro homocysteinylation of LDL isolated from control (n = 12) and DM subjects (n = 12) was carried out by incubating lipoproteins with Hcy-thiolactone. The reaction was verified by quantifying the increase in sulphydryl groups (-SH groups) in Hcy-LDL with respect to control LDL. Control and homocysteinylated LDL were incubated with human aortic endothelial cells (HAEC) in culture. Peroxynitrite production in cells treated in different experimental conditions was assayed by a fluorimetric method. RESULTS: The increase in -SH groups after incubation with homocysteine was greater in LDL from diabetic subjects compared with LDL from control subjects (P < 0.001). In addition, peroxynitrite production from HAEC incubated with Hcy-LDL from diabetic patients was greater than after incubation with Hcy-LDL from control subjects and untreated LDL from diabetic patients (P < 0.001). CONCLUSIONS: These results show that LDL from diabetic patients is more susceptible to in vitro homocysteinylation than LDL from non-diabetic individuals and demonstrate that the compositional changes in Hcy-LDL from diabetic subjects have cytotoxic effects on human endothelial cells.