Long-term airborne lead exposure, even below official occupational limits, has been found to cause lead poisoning at higher frequencies than expected, which suggests that China's existing occupational exposure limits should be reexamined. A retrospective cohort study was conducted on 1832 smelting workers from 1988 to 2008 in China. These were individuals who entered the plant and came into con...

Aberration-corrected electron microscopy can resolve the smallest atomic bond-lengths in nature. However, high-convergence angles that enable spectacular resolution 2D have unknown 3D limits for all but objects ($< \sim$8nm). We show aberration-corrected tomography offers new imaging by measuring several focal planes at each specimen tilt. present a theoretical foundation establishing analytic ...

BACKGROUND AND PURPOSE Computer-assisted navigation is increasingly used in functional endoscopic sinus surgery (FESS) to prevent injury to vital structures, necessitating preparative CT and, thus, radiation exposure. The purpose of our study was to investigate currently used radiation doses for CT in computer-assisted navigation in sinus surgery (CAS-CT) and to assess minimal doses required. ...

background: a substantial part of the public’s natural radiation dose is due to the inhalation of radon gas. most of the exposure occurs indoors where the airborne concentration of radon and its decay products is usually higher than outdoors. materials and methods: radon activity concentration has been measured twice in 50 classrooms in 5 levels (10 each) during summer and winter using solid-st...

Aims: It was aimed to investigate postoperative conformal radiotherapy planning that provides the best target volume and the least dose for critical organs in cancers of stomach. Methods: This study was conducted on the CT simulation images of thirty patients diagnosed with gastric cancer. Target volumes and the organs at risk were contoured. AP-PA reciprocal parallel field conventional plan an...

The opiate antagonist naltrexone (Ntx) has demonstrated efficacy in the treatment of alcohol dependence and as a component of treatment to reduce heavy drinking. At present, there are no published dose-ranging clinical trials of the oral preparation for treatment of problem drinking. The present study evaluated the effects of Ntx on alcohol use among the subset of hazardous drinkers (n=102) who...