室内氡的危害研究进展

阐述了人类赖以生存的环境中氡的来源、性质、进入人体的途径及致病机制和主要危害。同时介绍了世界各国在氡研究领域中的现状和最新进展情况。资料表明：随着经济的发展，住宅的条件逐步得到改善，特别是家庭空调的使用，以及不适当建筑材料或装饰材料的使用，已经使室内氡的问题成为人人都要面临的普遍性问题。介绍了过去10年各国对氡的研究情况，包括室内空气中氡的浓度，它给人们带来的内照射剂量，以及为减少氡所带来的危害要采取的补救措施和降低室内氡的主要技术方法。     

染铅对大鼠脾脏NOS、NO、SOD、MDA的影响

目的 探讨染铅对大鼠脾脏一氧化氮合酶（NOS）活力、一氧化氮（NO）含量的影响及其与血铅相互关系。方法 Wistar大鼠经饮水（加0，18．4，184．0mg/L醋酸铅，分别供对照组、低剂量组、高剂量组自由饮用）染毒，测定脾脏NOS活力、NO含量、SOD活力、MDA含量。结果 NOS活力高剂量染铅组7d时显著低于对照组和低剂量组（P＜0．05），90d高于对照组和低剂量组（P＜0．05），低剂量组90d高于对照组（P＜0．05）；NO含量高剂量组和低剂量组60d、90d时均显著低于对照组（P＜0．05）；SOD活力高剂量组14d、30d、60d、90d时均低于对照组（P＜0．05），低剂量组30d、90d时显著低于对照组（P＜0．05）；MDA含量高剂量组14d、60d、90d时均显著高于对照组，60d时显著低于低剂量组，90d时显著高于低剂量组（P＜0．05），低剂量组在各时点与对照组比较，差异无显著性（P＞0．05）。血铅与脾脏NO含量呈倒S型剂量－效应曲线；血铅与脾脏SOD活力呈倒抛物线型剂量－效应曲线；血铅与脾脏MDA含量呈正抛物线型剂量－效应曲线。结论 铅可引起大鼠脾脏NOS活力、NO含量、SOD活力、MDA含量改变，表明铅可引起体内氧应激反应导致脂质过氧化损伤。     

House dust mites and human dander

The occurrence of house dust mites was measured in the homes of 12 patients with the scaly skin disease, psoriasis. The median number of mites in the mattress dust and floor dust was 27 (range 10-153)/0.1 g and 56 (range 12-114)/0.1 g respectively, which is significantly higher than the background pollution of house dust mites in normal Danish homes. The results support the idea that the amount of mites in our homes not only depend on relative air humidity but also on the production of dandruff.     

Relation of radon exposure and tobacco use to lung cancer among tin miners in Yunnan Province, China

We studied the relation of radon exposure and tobacco use to lung cancer among tin miners in Yunnan Province in the People's Republic of China. Interviews were conducted in 1985 with 107 living tin miners with lung cancer and an equal number of age-matched controls from among tin miners without lung cancer to obtain information on lung cancer risk factors including a detailed history of employment and tobacco use. Occupational history was combined with extensive industrial hygiene data to estimate cumulative working level months (WLM) of radon daughter exposure. Similar data were also used to estimate arsenic exposure for control in the analysis. Results indicate an increased risk of lung cancer for water pipe smoking, a traditional form of tobacco use practiced in 91% of cases and 85% of controls. Ever use of water pipes was associated with a twofold elevation in risk when compared with tobacco abstainers, and a dose-response relation was observed with increasing categories of pipe-year (dose times duration) usage. Estimated WLM of radon exposure varied from 0 to 1,761 among subjects but averaged 515 in cases versus only 244 in controls. Analyses indicated that the persons in the highest quarter of the radon exposure distribution had an odds ratio (OR) = 9.5 (95% confidence interval = 2.7-33.1) compared to persons without radon exposure after controlling for arsenic exposure and other potential confounders. Examination of duration and rate of radon exposure indicated higher risk associated with long duration as opposed to high rate of exposure. Cross-categorizations of radon exposure and tobacco use suggest greater risk associated with radon exposure than tobacco in these workers.     

Low-level cadmium exposure increases one-way avoidance in juvenile rats

Twenty-seven pregnant rats from three genetic lines, Roman High Avoidance (RHA), Roman Low Avoidance (RLA), and Satinder's Heterogeneous Stock (SHS), received daily SC injections of either 0.075 mg/kg CdCl₂ (low dose), 0.225 mg/kg CdCl₂ (high dose), or an equivalent volume of saline vehicle (control) throughout gestation. Cd-exposed progeny from the RHA genetic line weighed significantly less than RHA control progeny (pd 35–44); however, SHS progeny from the low-dose group weighed significantly more than progeny from any other group (pd 14–44). Unconditioned escape response (UER) level was determined on pd 39. Progeny from the high-dose group required a significantly lower UER level as compared to the low-dose group. Acquisition of conditioned avoidance responses was tested from pd 41 to 44. There were significant differences due to dose for one-way avoidance responses. Cd-related differences in one-way avoidance were restricted to progeny from the SHS genetic line. SHS progeny from the high-dose group demonstrated significantly more one-way responses when compared to the control group. Differences in avoidance responses are discussed in relation to Cd-induced hyper-nociception. The concentration of Cd in the liver and kidney of dams and progeny was determined by Inductively Coupled Plasma spectroscopy (ICP). There were significant dose-related differences in Cd concentration in maternal tissues.     

红外分光光度法与焦磷酸重量法测定粉尘中游离二氧化硅的比较

本文对矿山粉尘和铸造粉尘的游离二氧化硅含量进行了红外分光光度法和焦磷酸重量法的对比测定。结果表明,红外法与重量法的结果之间有很好的相关性,其测定值在统计学上无显著性差异。两法测定值的相关回归方程:(?)=1.0001×-2.0610,r=0.947997。红外法的测定不受灰化的影响,对滤膜采集的粉尘中游离二氧化硅的含量测定是一简便、快速的方法,可较好地排除粉尘中难溶或不溶物质和无定形二氧化硅等因素的干扰,克服了重量法的不足。     

Inflammation of the visceral pleura, a nonspecific asbestos-related pleural reaction: chest radiograph and computed tomograph correlation

Nonspecific pleuritis, i.e., inflammation of the visceral pleura, is recognized by the presence of pleural strands on the routine posteroanterior chest radiograph. The computed tomograph counterparts of these strands are seen as interlobular septal intrusions and lenticular or wedge-shaped subpleural opacities. The pleural reaction is nonspecific and may be found with asbestos exposure, traumatic hemorrhagic effusions, pulmonary embolism, viral pleurisy, malignant pleural effusions, and lupus or rheumatoid effusions. The asbestos-related pleural changes may be found alone or in association with parietal pleural plaque formation or with asbestotic lung fibrosis.     

桡神经第二掌背支携筋膜蒂逆行岛状皮瓣修复指背骨外露

目的 探讨桡神经第二掌背支携筋膜蒂逆行岛状皮瓣修复指背骨外露的临床效果.方法 以桡神经第二掌背支携筋膜蒂逆行岛状皮瓣修复食指和中指中节指背骨外露患者共3例,观察皮瓣的成活率、质地、色泽.结果 随访3～24个月,平均18个月.3例皮瓣全部顺利成活,指端创面均获得覆盖;供区创面顺利愈合;皮瓣质地、弹性均正常,皮色与受区一致,无溃疡发生.结论 桡神经第二掌背支携筋膜蒂逆行岛状皮瓣修复指背骨外露具有操作相对简单、安全,皮瓣质地、色泽与受区一致等优点. Abstract： Objective To explore the clinical effect of reparing the bone exposure of finger back with a reverse island flap of the second metacarpal dorsal nerve of superficial radial nerve together with fascial pedicle.Methods Three cases with the bone exposure of finger back were repaired with a reverse island flap of the second metacarpal dorsal nerve of superficial radial nerve together with fascial pedicle.Then the survival rate, texture, and colour of the flaps were observed.Results All cases were followed up from 3 to 24 months (with the mean of 18 months).The flaps totally survivied in 3 cases, the bone exposure were repaired excellently.The raw surface of donor site were repaired.The flaps possessed good texture and flexibility.The flaps possess good quality and their colour match the recipient site.Conclusions The reverse island flap of the second metacarpal dorsal nerve of superficial radial nerve together with fascial pedicle is alternative to repair the bone exposure of finger back.The operation is easy and safe.     

Bayesian spatial modeling of disease risk in relation to multivariate environmental risk fields

The relationship between exposure to environmental chemicals during pregnancy and early childhood development is an important issue that has a spatial risk component. In this context, we have examined mental retardation and developmental delay (MRDD) outcome measures for children in a Medicaid population in South Carolina and sampled measures of soil chemistry (e.g. As, Hg, etc.) on a network of sites that are misaligned to the outcome residential addresses during pregnancy. The true chemical concentration at the residential addresses is not observed directly and must be interpolated from soil samples. In this study, we have developed a Bayesian joint model that interpolates soil chemical fields and estimates the associated MRDD risk simultaneously. Having multiple spatial fields to interpolate, we have considered a low‐rank Kriging method for the interpolation that requires less computation than the Bayesian Kriging. We performed a sensitivity analysis for a bivariate smoothing, changing the number of knots and the smoothing parameter. These analyses show that a low‐rank Kriging method can be used as an alternative to a full‐rank Kriging, reducing the computational burden. However, the number of knots for the low‐rank Kriging model needs to be selected with caution as a bivariate surface estimation can be sensitive to the choice of the number of knots. Copyright © 2009 John Wiley & Sons, Ltd.