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71.
Smith JR Edland SD Novotny TE Hofstetter CR White MM Lindsay SP Al-Delaimy WK 《American journal of public health》2011,101(10):1876-1879
Hookah use is gaining popularity nationwide. We determined the correlates and trends for hookah use from the California Tobacco Survey. Between 2005 and 2008 hookah use increased more than 40%, and in 2008, 24.5% of young men reported ever using a hookah. Hookah use was more common among the young (18-24 years), the educated, the non-Hispanic Whites, and the cigarette smokers. Hookah use is increasing in California, especially among young adults, and in 2008 reached the highest prevalence ever reported for both genders. 相似文献
72.
Rebreathing of expired air may be a lethal hazard for prone sleeping infants. This paper describes a mechanical model to simulate infant breathing, and examines the effects of bedding on exhaled air retention. Under simulated rebreathing conditions, the model allows the monitoring of raised carbon dioxide (CO2) inside an artificial lung-trachea system. Resulting levels of CO2 (although probably exaggerated in the mechanical model compared with an infant, due to the model's fixed breathing rate and volume) suggest that common bedding materials vary widely in inherent rebreathing potential. In face down tests, maximum airway CO2 ranged from less than 5% on sheets and waterproof mattresses to over 25% on sheepskins, bean bag cushions, and some pillows and comforters. Concentrations of CO2 decreased with increasing head angle of the doll, away from the face down position. Recreations of 29 infant death scenes also showed large CO2 increases on some bedding materials, suggesting these infants could have died while rebreathing. 相似文献
73.
Polysaccharide of Danggui Buxue Tang,an Ancient Chinese Herbal Decoction,Induces Expression of Pro‐inflammatory Cytokines Possibly Via Activation of NFκB Signaling in Cultured RAW 264.7 Cells 下载免费PDF全文
74.
75.
心房扑动患者的下腔静脉-三尖瓣环峡部和房间隔缓慢传导的电生理意义 总被引:1,自引:0,他引:1
目的 用电 解剖标测方法标测右心房 ,然后比较心房扑动 (AFL)和房室结折返性心动过速(AVNRT)患者在下腔静脉 三尖瓣环峡部 (CTI)和心房间隔部 (AS)的电冲动传导速度 ,以便确定AFL患者除了解剖结构上的异常外 ,是否伴有心房电生理方面的异常变化。方法 1 0例AFL患者 ,男性 7例 ,女性 3例 ,平均 (53± 1 0 )岁 ;1 3例AVNRT患者 ,男性 5例 ,女性 8例 ,平均 (51± 1 1 )岁。对这两组患者进行了详细的电 解剖标测、电生理检查和射频消融术。分别以周长为 60 0、40 0、和 30 0ms在冠状静脉窦 (CS)起搏的情况下测量AFL和AVNRT患者的CTI和AS的冲动传导速度 ,并将两组患者在CTI和AS的冲动传导速度进行比较。结果 与AVNRT患者相比 ,AFL患者在各个起搏周长 (PCL)时CTI和AS的冲动传导速度都明显减慢 (P <0 0 5)。另外 ,在AFL组 ,AS的冲动传导速度在起搏周长 60 0、40 0ms时低于CTI,但在 30 0ms时差异无显著性 (P >0 0 5)。因为在AFL组 ,PCL为 30 0ms时的冲动传导速度明显低于 60 0和 40 0ms时的冲动传导速度 ,致使PCL为 30 0ms时CTI和AS的冲动传导速度差异无显著性。结论 与CTI相比 ,AS的冲动传导速度在所有患者都较慢 ,而AFL患者在CTI和AS的冲动传导速度减低更明显 ,并且在CTI的冲动传导速度减慢具有频率依 相似文献
76.
Bony inlet stenosis as a cause of nasal airway obstruction 总被引:2,自引:0,他引:2
Two cases of congenital bony stenosis of the nasal piriform aperture (anterior nares) are presented. Both patients experienced episodes of respiratory distress and clinical symptoms similar to those seen in patients with posterior choanal atresia. The underlying anatomic abnormalities in congenital bony inlet stenosis are quite different from those in choanal atresia and require different surgical approaches for correction. Computed tomography demonstrates in detail the underlying anatomic abnormality and allows differentiation of bony inlet stenosis from choanal atresia. 相似文献
77.
Asthma is the most common chronic pulmonary disease worldwide and places a considerable economic burden on society. China is the world''s largest developing country and has the largest population. China has undergone dramatic changes in the past few decades. The traditional lifestyle and living environment have changed in ways that directly affect the prevalence of asthma. The prevalence of asthma is lower in Chinese children and adults than in developed countries, but the prevalence has been on the rise during the past 30 years. The prevalence significantly varies among different parts of China. Polymorphisms of multiple genes, outdoor air pollution caused by PM2.5, PM10, SO2, NO2, environmental tobacco smoke, and coal, indoor pollution, and inhaled allergens, such as house dust mites, pollen, and cockroach particles, are risk factors for asthma. 相似文献
78.
Eugenia HC Woo Peter White Christopher WK Lai 《Journal of paediatrics and child health》2016,52(6):590-594
This article provides a general framework for understanding the use of information and communication technology in education and discusses the impact of computer usage on students' health and development. Potential beneficial and harmful effects of computer use by children are discussed. Early epidemiological and laboratory studies have indicated that children are at least of similar risk of developing musculoskeletal and vision problems as adults, and musculoskeletal and visual health problems developed in childhood are likely to persist into adulthood. This article, therefore, aims to provide a reflection on the deficits of existing policy and recommendations for child‐specific guidelines in computer use. 相似文献
79.
目的:观察染料木黄酮对成骨细胞活性的影响及其相关机制。方法:实验于2001-05/2003-05在卫生学环境医学研究所实验室完成。①成骨细胞培养:无菌条件下分离出生3d的乳鼠颅盖骨,剪碎,加入胰蛋白酶和Ⅱ型胶原酶,用含体积分数为0.1的胎牛血清的F-12培养基重悬,调整细胞浓度后接种于25mL细胞培养瓶,Ⅱ代细胞用于实验。②实验方法:实验分为染料木黄酮组、雌激素组和对照组(吐温20),染料木黄酮剂量分别为10-5,10-6、10-7mol/L,雌激素剂量分别为10-9,10-10mol/L,培养48,72h后,应用MTT和3H-TdR掺入实验观察不同剂量的染料木黄酮和雌激素对成骨细胞活性影响,免疫组化的方法测定白细胞介素6表达。结果:①A570nm值:培养48h,染料木黄酮10-5,10-6,10-7mol/L组分别比对照组增加105%,136%和143%;10-9,10-10mol/L雌激素组分别比对照组增加84%和100%;培养72h,染料木黄酮3个剂量组分别比对照组增加93%,113%和146%,各剂量组与对照组相比均有显著性差异(P<0.05)。②3H-TdR掺入量:10-5,10-6,10-7mol/L染料木黄酮组分别比对照组增加0.47,11.29,6.45倍;10-9和10-10mol/L雌激素组增加15.4倍和16.5倍(P<0.05)。③白细胞介素6表达:各组成骨细胞周围均有较强的呈棕色的阳性颗粒,但染料木黄酮组组与对照组相比无明显差别。结论:①10-5~10-7mol/L染料木黄酮和雌激素一样可促进成骨细胞增殖和DNA合成。②染料木黄酮不是通过促进白细胞介素6表达来促进成骨细胞增殖与分化。 相似文献