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991.
Association between indoor and outdoor air pollution and adolescent asthma from 1995 to 1996 in Taiwan 总被引:2,自引:0,他引:2
The study aim was to estimate the contribution of indoor and outdoor air pollution to the 1-year prevalence of adolescent asthma after personal susceptibility and other potential risk factors were taken into account. A large-scaled cross-sectional study was conducted among 165,173 high school students aged 11 to 16 years in the different communities of Kaohsiung and Pintong in Taiwan, from October 1995 to June 1996. Each student and his/her parents participating in the study completed a video and a written International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire about symptoms of wheezing and allergies, passive smoking, and demographic variables. After adjustment for potential confounders, adolescents exposed to cigarette smoking (odds ratio = 1.29, 95% confidence interval (CI), 1.17-1.42) and environmental tobacco smoke (odds ratio = 1.08, 95% CI, 1.05-1.12) were found to suffer from asthma at an increased frequency. We observed a statistically significant association between outdoor air pollution and asthma, after controlling for potential confound variables. Total suspended particulate, nitrogen dioxide, carbon monoxide, ozone, and airborne dust particles all displayed an independent association with asthma, respectively. There were no selection biases in this community-based study, which provides evidence that passive smoking and long-term, high average outdoor air pollution are independent risk factors of asthma. 相似文献
992.
Climate, traffic-related air pollutants, and asthma prevalence in middle-school children in taiwan 总被引:7,自引:0,他引:7 下载免费PDF全文
Guo YL Lin YC Sung FC Huang SL Ko YC Lai JS Su HJ Shaw CK Lin RS Dockery DW 《Environmental health perspectives》1999,107(12):1001-1006
This study compared the prevalence of asthma with climate and air pollutant data to determine the relationship between asthma prevalence and these factors. We conducted a nationwide survey of respiratory illness and symptoms in middle-school students in Taiwan. Lifetime prevalences of physician-diagnosed asthma and of typical symptoms of asthma were compared to air monitoring station data for temperature, relative humidity, sulfur dioxide, nitrogen oxides, ozone, carbon monoxide, and particulate matter with aerodynamic diameter [less than/equal to] 10 microm (PM(10)). A total of 331,686 nonsmoking children attended schools located within 2 km of 55 stations. Asthma prevalence rates adjusted for age, history of atopic eczema, and parental education were associated with nonsummer (June-August) temperature, winter (January-March) humidity, and traffic-related air pollution, especially carbon monoxide and nitrogen oxides, for both girls and boys. Nonsummer temperature, winter humidity, and traffic-related air pollution, especially carbon monoxide and nitrogen oxides, were positively associated with the prevalence of asthma in middle-school students in Taiwan. 相似文献
993.
Paroxetine (Paxil) is a widely prescribed antidepressant of the selective serotonin reuptake inhibitor (SSRI) class for which multiple cutaneous adverse effects have been reported, including urticaria, ecchymoses, vasculitis, and pruritus. In contrast, fluoxetine (Prozac) is the only SSRI previously reported to cause urticarial vasculitis. Urticarial vasculitis is a chronic disorder marked by recurrent episodes of erythematous, indurated wheals that histologically manifest the features of leukocytoclastic vasculitis. This case represents the first reported incidence of paroxetine-induced urticarial vasculitis, and highlights the need to consider the entire SSRI class as s as a potential cause of the condition. 相似文献
994.
STUDY OBJECTIVE: To compare the cost-effectiveness of various antimuscarinic agents for the treatment of overactive bladder (OAB). METHODS: A decision-analysis model was developed and included clinical outcomes (i.e., therapy continued or discontinued, treatment success or failure, OAB-induced comorbidities) and costs for drugs and treatment of OAB-induced comorbidities (i.e., urinary tract infections, fractures, depression, and skin infections). Treatment success was defined as complete continence. A systematic MEDLINE literature search from January 1990-January 2006 identified English-language articles concerning the eight antimuscarinic drugs: darifenacin, solifenacin, trospium, immediate-release oxybutynin, extended-release oxybutynin, transdermal oxybutynin, immediate-release tolterodine, and extended-release tolterodine. Probabilities and cost data for these drugs were retrieved from the literature, and drug costs were based on 2005 average wholesale prices. The analysis was constructed from a payer's perspective. The time frame for the model was 3 months. RESULTS: Expected costs for each patient with OAB ranged from $3373 when treated with solifenacin to $3769 when treated with immediate-release oxybutynin. The average cost/patient with continued and successful treatment was lowest for solifenacin ($6863). Solifenacin dominated all other antimuscarinic agents because they were associated with high costs and low effectiveness. Success rates were the key parameters driving the sensitivity analysis. CONCLUSION: Among various antimuscarinic agents, solifenacin 5 mg had the lowest costs and highest effectiveness in the treatment of OAB. 相似文献
995.
Deltamethrin, a synthetic pyrethroid contaminating aquatic ecosystems as a potential toxic pollutant, was investigated in the present study for acute toxicity. The purpose of this study was to evaluate LC(50) values of deltamethrin on Nile tilapia (Oreochromis niloticus L.) fingerlings and investigate histopathological responses of fish exposed to deltamethrin. The 48 h LC(50) value for Nile tilapia fingerlings was estimated as 4.85 microg/L using static test system. In addition, behavioral changes at each deltamethrin concentration were observed closely. All fish, exposed to 5 microg/L deltamethrin revealed severe morphological alterations in the gills and liver. In the gills hyperemia, fusion of secondary lamellae and telangiectasis were observed; whereas hydropic degenerations in liver were observed in all examined fish. The results are significant for reporting acute deltamethrin toxicity in terms of behavioral and histopathological changes: Deltamethrin is highly toxic to fingerlings. 相似文献
996.
The potential of tacrine in altering cognitive/behavioral function as well as in causing toxicity was evaluated in mice of 17 and 30 days of age. Cognitive and behavioral studies were performed using a step-through passive avoidance task and a habituation open-field test with a 24-h retention interval. Tacrine was subcutaneously injected (1.25-80 micro mol/kg) 30 min prior to the first session of both tests. During the training session in step-through task, tacrine treatment dose-dependently decreased the number of footshocks, with IC(50) values being 7.8 and 23.3 micro mol/kg in 17- and 30-day-old mice, respectively. Treatment with tacrine at a low dose (5 micro mol/kg) significantly prolonged the retention latency in 17-day-old mice only, but it shortened the retention latency at high doses of 20 and 40 micro mol/kg in 17- and 30-day-old, respectively. During the acquisition session in the open-field test, tacrine treatment dose-dependently decreased the locomotor activity in 17- and 30-day-old mice, with IC(50) values being 15.1 and 24.7 micro mol/kg, respectively. High doses of tacrine invariably increased the locomotor activity during the recall session. Tacrine treatment at a dose of 40 micro mol/kg caused a significant increase in serum alanine aminotransferase activity in 17- and 30-day-old mice at 6 h post-dosing, with the extent of stimulation in 30-day-old mice being more prominent. In conclusion, tacrine was more potent in enhancing/disrupting the cognitive function, inhibiting locomotor activity as well as in causing hepatotoxicity in 17-day-old than in 30-day-old mice. 相似文献
997.
998.
This study was aimed to examine the Attitudes-Social influence-Efficacy Model for the use of MDMA among college students in Taiwan. A representative sample of 3743 college students participated in this study. Each participant completed a comprehensive survey and 3090 valid data were collected. Correlation analyses displayed that either positive outcome expectancy or social influence was positively related to intention while refusal self-efficacy was negatively associated with intention. Using the Structural Equation Model, the results showed that the model fitted the data well. Intention for using MDMA affected MDMA use. Refusing self-efficacy significantly predicted intention and MDMA use indirectly via intention. Social influence had a direct impact on intention or MDMA use as well as an indirect effect on MDMA use via intention. However, positive outcome expectancy did not have an effect on both intention and the use of MDMA. Our results suggested that preventive programs in colleges for MDMA use should focus on developing strategies in decreasing the social influence and enhancing the refusal self-efficacy. 相似文献
999.
Chen PH Tsai CC Lin YC Ko YC Yang YH Shieh TY Ho PS Li CM Min-Shan Ko A Chen CH 《Journal of toxicology and environmental health. Part A》2006,69(11):1055-1069
Areca quid (AQ) chewing has been implicated an independent risk factor for the development of oral cancer. Taiwanese areca quid (AQ) refers to a combination of areca nut (AN), lime, and inflorescence of Piper betle Linn. (IPB) or Piper betle leaf (PBL). Studies of AQ in other countries reported that AN extract combined with lime generates reactive oxygen species (ROS), such as hydroxyl radical (HO.), known to be a contributing factor in oral mucosa damage. To determine whether HO. is formed in the oral cavity during AQ chewing, the formation of meta-tyrosine (m-Tyr) and ortho-tyrosine (o-Tyr) from l-phenylalanine (Phe) was confirmed. It was demonstrated that combined aqueous extracts of AN, lime, metal ions (such as Cu2+ and Fe2+), and IPB or PBL produced HO.. Thus, the yield of HO. significantly increases when higher amounts of IPB or lime are added and also when Cu2+ and Fe2+ are increased. Further, the omission of any one of these ingredients significantly reduces the formation of HO.. Our results found that chewing AQ with IPB generated significantly higher HO. than chewing AQ with PBL, and may result in greater oxidative damage to the surrounding oral mucosa. 相似文献
1000.
Ulmus davidiana NAKAI (UDN) has traditionally been used for healing of inflammatory diseases. This study was carried out to investigate the hepatoprotective effect of the glycoprotein isolated from UDN in carbon tetrachloride (CCl4)-induced liver injury. We evaluated the activities of alanine aminotransferase (ALT), lactate dehydrogenase (LDH), thiobarbituric acid-reactive substances (TBARS), and antioxidant enzymes [superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx)] activities in CCl4-treated mice. When mice were treated with CCl4 in the absence of UDN glycoprotein, the activities of ALT, LDH, and TBARS were increased, while the antioxidant enzymes activities were decreased. However, when the mice were treated with CCl4 in the presence of UDN glycoprotein, the activities of ALT, LDH, and TBARS were significantly reduced and SOD, CAT, and GPx activities were remarkably increased. In addition, UDN glycoprotein increased the nitric oxide production and decreased the nuclear factor-kappa B and activator protein-1 activation in CCl4-treated mice. We also investigated the protective effects of UDN glycoprotein in glucose/glucose oxidase (G/GO)-induced cytotoxicity in primary cultured mouse hepatocytes. UDN glycoprotein markedly inhibited the cell death induced by G/GO. These results suggest that UDN glycoprotein protects against CCl4-induced liver injury in the mouse. 相似文献