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81.
Research into online addictions has increased substantially over the last decade, particularly amongst youth. This study adapted the Problematic Internet Entertainment Use Scale for Adolescents [PIEUSA] for use with a British population. The adapted scale was used to (i) validate the instrument for English-speaking adolescent samples, (ii) estimate the prevalence of adolescent online problem users and describe their profile, and (iii) assess the accuracy of the scale’s classification of symptomatology. A survey was administered to 1097 adolescents aged between 11 and 18 years. The results indicated that (i) reliability of the adapted scale was excellent; factor validity showed unidimensionality, and construct validity was adequate. The findings also indicated that (ii) prevalence of online problem users was 5.2% and that they were more likely to younger males that engaged in online gaming for more than two hours most days. The majority of online problem users displayed negative addictive symptoms, especially ‘loss of control’ and ‘conflict’. The adapted scale showed (iii) very good sensitivity, specificity, and classification accuracy, and was able to clearly differentiate between problem and non-problem users. The results suggest certain differences between adolescent and adult online problem users based in the predominance of slightly different psychological components. 相似文献
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83.
Respiratory activity and phenolic compounds in pre-cut celery 总被引:1,自引:0,他引:1
The effect of temperature on respiratory activity and total phenol and flavonoid contents in pre-cut celery was assessed within the 24 h following this minimal processing. To this end, celery petioles were cut as strips, conditioned in crystal polyethylene terephthalate trays covered with PVC film and stored at 0, 10 and 20 °C. Samples were removed at 0, 2, 4, 6 and 24 h after processing to analyse respiratory activity and concentrations of total phenols and flavones. For the samples kept at 0 °C for 24 h, chlorogenic acid was also determined, along with total flavonoids and antioxidant power. At this temperature, the total phenol contents remained basically constant, though at 10 °C it increased considerably two hours after applying the cutting stress. At 20 °C the increase observed was less important. The flavones, identified by HPLC in pre-cut celery were apigenin and luteolin, whose concentrations also increased between two to six hours after processing. However, exposure for 24 h at 0 °C produced a considerable decrease in total flavonoids. 相似文献
84.
Modified atmosphere packaging improved quality of kohlrabi stems 总被引:1,自引:0,他引:1
Víctor H. Escalona 《LWT》2007,40(3):397-403
To improve the keeping quality of the kohlrabi stems and avoiding wilting of the leaves, modified atmosphere packaging (MAP) with oriented polypropylene and amide-polyethylene copolymer bags was applied. Avoiding wilting of the kohlrabi leaves is crucial because European consumers consider the freshness of kohlrabi leaves as a key quality parameter. Whole kohlrabies were stored within, above-mentioned sealed bags, for 14 days at 0 °C and 95% RH, followed by 3 days at 10 °C. In the MA packages gas compositions of about 5 kPa O2 and 10-15 kPa CO2 were generated. The respiratory activity, C2H4 production, firmness (of stems and leaves), sugars, organic acids contents, as well as chemical and sensory quality attributes were monitored. The respiratory rate of the kohlrabi stems in air at 0 °C was 10-11 mg CO2/kg/h with a C2H4 production lower than 0.05 μl/kg/h (traces). However, when the temperature was increased at 10 °C the respiration rate raised 3.5 folds. Acidity, pH, soluble solids, sugars and organic acids content and firmness did not show significant changes at the end of both cold storage and retail sale periods. MAP was very effective improving keeping quality of the stems and retarding wilting of the leaves. During the retail sale period at 10 °C, the bags must to be perforated to avoid anaerobic conditions. 相似文献
85.
目的 结合临床实践经验,对肺间质病变进行临床分析。方法 选取我院2005年1月至2009年12月期间31例肺间质病变患者为研究对象,总结患者的临床资料,采用回顾性研究的方法对其进行总结分析,探讨肺间质病变的发病病因、临床特点及诊治方法。结果 常见病因有长期大量吸烟、风湿性关节炎以及粉尘接触,临床特点有进行性呼吸困难、干咳、杵状指、双肺均可闻及湿啰音、两肺底可闻及爆破音以及双肺可闻及干啰音喙卣锒现副昙恚场丁V瘟品椒ㄎ∮没妨柞0贰⒓谆康乃闪⒑烀顾氐冉兄瘟疲?效率为56.75%。结论 肺间质病变的诊断是要依据病史、临床表现、结合肺功能、动脉血气分析、胸片、胸CT检查的结果进行。而治疗方面目前尚未发现特效药,常规药物治疗效果差,有待改善和提高。 相似文献
86.
Sandra Axberg Plsson Vaishnovi Sekar Claudia Kutter Marc R. Friedlnder Anna-Lena Spetz 《International journal of molecular sciences》2022,23(11)
Respiratory syncytial virus (RSV) causes acute lower respiratory tract infection in infants, immunocompromised individuals and the elderly. As the only current specific treatment options for RSV are monoclonal antibodies, there is a need for efficacious antiviral treatments against RSV to be developed. We have previously shown that a group of synthetic non-coding single-stranded DNA oligonucleotides with lengths of 25–40 nucleotides can inhibit RSV infection in vitro and in vivo. Based on this, herein, we investigate whether naturally occurring single-stranded small non-coding RNA (sncRNA) fragments present in the airways have antiviral effects against RSV infection. From publicly available sequencing data, we selected sncRNA fragments such as YRNAs, tRNAs and rRNAs present in human bronchoalveolar lavage fluid (BALF) from healthy individuals. We utilized a GFP-expressing RSV to show that pre-treatment with the selected sncRNA fragments inhibited RSV infection in A549 cells in vitro. Furthermore, by using a flow cytometry-based binding assay, we demonstrate that these naturally occurring sncRNAs fragments inhibit viral infection most likely by binding to the RSV entry receptor nucleolin and thereby preventing the virus from binding to host cells, either directly or via steric hindrance. This finding highlights a new function of sncRNAs and displays the possibility of using naturally occurring sncRNAs as treatments against RSV. 相似文献
87.
88.
Outi M. Koskinen Tuula M. Husman Anne M. Hyvrinen Tiina A. Reponen Aino I. Nevalainen 《Indoor air》1997,7(4):262-268
Abstract The aim was to study the respiratory symptoms among children exposed to indoor air molds in a day-care environment in Finland. Two day-care centers with a mold problem and two reference day-care centers were included in the study and the health data of the children were collected with a follow-up study of two periods. A total of 229 children 3-7 years old attended the day-care centers. During the first follow-up period, the children in the two day-care centers with mold problems had a significantly increased risk of sore throat, purulent and non-purulent nasal discharge, nasal congestion, hoarseness and common cold. During the second follow-up period, a significantly increased risk of purulent nasal discharge, nasal congestion, hoarseness and cough was observed. Upper respiratory tract symptoms, at least once during the study period, were more prevalent among the children attending mold-problem day-care centers. The mold-exposed children had such symptoms repeatedly or the symptoms were prolonged. In conclusion, in the mold-problem day-care centers, overall morbidity for respiratory symptoms and for common cold increased in comparison with the reference day-care centers. 相似文献
89.
Sensory Responses To Environmental Tobacco Smoke From Tobacco-Burning And Tobacco-Heating Cigarettes
James C. Walker Roger A. Jennings Paul R. Nelson Walter T. Morgan David L. Heavner John H. Robinson J. Don DeBethizy Melanie W. Stancill 《Indoor air》1993,3(3):170-180
Sensory ratings, respiratory behavior and eye blink rate were recorded in 11 nonsmokers exposed to a no-smoking (CONTROL) condition or to environmental tobacco smoke (ETS) from one of three kinds of cigarettes: a Kentucky reference (1R4F), an ultra-low tar (ULT) and one that heats tobacco (TEST).For each two-hour session in a controlled-environment room, two smokers “puffed” unlit cigarettes, for the CONTROL condition, or smoked 16 cigarettes to generate ETS (sidestream plus exhaled mainstream smoke). Concentrations of nicotine and respirable suspended particles (RSP) observed with the 1R4F and ULT cigarettes were 10- to 20-fold higher than those typically found in field sampling studies of office and restaurant smoking environments. The ULT and TEST cigarettes resulted in ETS analyte concentrations that were 77-100% and O-56%, respectively, of those observed with 1R4E Sensory ratings (odor, irritation, annoyance, acceptability) with the two tobacco-burning cigarettes were similar and were much greater than those recorded for the TEST or CONTROL conditions which were, in turn, rated similarly. Respiratory parameters (respiratory rate, tidal volume, expiratory time), which generally failed to discriminate the TEST and CONTROL conditions, were altered during exposure to ETS from the 1R4F and, to a lesser extent, the ULT cigarette. Eye blink rate was not significantly altered by ETS from any of the cigarettes. 相似文献
90.
Watson David; O'Hara Michael W.; Chmielewski Michael; McDade-Montez Elizabeth A.; Koffel Erin; Naragon Kristin; Stuart Scott 《Canadian Metallurgical Quarterly》2008,20(3):248
The authors explicated the validity of the Inventory of Depression and Anxiety Symptoms (IDAS; D. Watson et al., 2007) in 2 samples (306 college students and 605 psychiatric patients). The IDAS scales showed strong convergent validity in relation to parallel interview-based scores on the Clinician Rating version of the IDAS; the mean convergent correlations were .51 and .62 in the student and patient samples, respectively. With the exception of the Well-Being Scale, the scales also consistently demonstrated significant discriminant validity. Furthermore, the scales displayed substantial criterion validity in relation to Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV; American Psychiatric Association, 1994) mood and anxiety disorder diagnoses in the patient sample. The authors identified particularly clear and strong associations between (a) major depression and the IDAS General Depression, Dysphoria and Well-Being scales, (b) panic disorder and IDAS Panic, (c) posttraumatic stress disorder and IDAS Traumatic Intrusions, and (d) social phobia and IDAS Social Anxiety. Finally, in logistic regression analyses, the IDAS scales showed significant incremental validity in predicting several DSM-IV diagnoses when compared against the Beck Depression Inventory-II (A. T. Beck, R. A. Steer, & G. K. Brown, 1996) and the Beck Anxiety Inventory (A. T. Beck & R. A. Steer, 1990). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献