Pneumothorax and other lung diseases: effect of altered resolution and edge enhancement on diagnosis with digitized radiographs

Prior studies have shown that pneumothorax is one of the more difficult entities to diagnose with digitized radiography. This study was designed to test whether increasing resolution from 1.25 to 2.5 line pairs per millimeter (lp/mm) and image processing (edge enhancement from unsharp masking) would increase accuracy and confidence in the diagnosis of pneumothorax, as well as normal cases and other forms of lung disease. Conventional radiographs were digitized with use of a laser reader and then reformatted as film hard copy. Eleven observers read 35 cases reformatted in three different ways (1.25 lp/mm, 2.5 lp/mm, 1.25 lp/mm unsharp mask). The images with finer resolution (2.5 lp/mm) and unsharp mask images were superior to those with coarser resolution (1.25 lp/mm) for the diagnosis of pneumothorax. There was no difference in diagnostic accuracy for normal patients. For abnormalities other than pneumothorax, the unsharp mask images were significantly worse. Confidence in the diagnosis of pneumothorax and other abnormalities was highest with the finest resolution (2.5 lp/mm).     

Preventive oral health related behaviour of dentally anxious schoolchildren aged 13-14 years in Lothian, Scotland.

The aim of this study was to determine the self-reported preventive oral health related behaviours of dentally anxious schoolchildren. 1103 children participated in the study, mean age 14 years (SD 0.35 years), and the prevalence of high dental anxiety was 7.1 per cent (95 per cent confidence interval = 5.6 per cent, 8.6 per cent). Children with high self reported dental anxiety were more likely to defer, cancel and or not attend dental appointments. In addition, for this group the last dental visit was more likely to be as a result of pain and less likely to have been for a dental examination only. Overall dentally anxious children did not help themselves by keeping their teeth clean. Fluorides were infrequently used by all the children, and only 12 per cent of all who participated in the study used fluoride supplements regularly. In this context it is not surprising that no differences in present or past use of fluoride supplements could be determined between high and low/moderate dental anxiety groups. The high dental anxiety group spend significantly more (median = 50p) on sweets per day and drank more cans of fizzy drinks (median = 2) compared with the low/moderate anxiety groups. These effects were significant after taking into account social class and gender differences. It was clear from the study that even when social class and gender are taken into account the children with high dental anxiety were not helped by their relatively poor attitudes towards preventing disease in their own mouths.     

导数光谱系数倍率法测定多组分体系感冒清胶囊中盐酸吗啉胍的含量

This paper provides a basic principle and experimental technique of derivative signal multiplier spectrophotometry in multicomponent mixture. A microcomputer was used to process the spectral data measured on a manual spectrophotometer (UV-7520) for the determination of moroxydine hydrochloride in Gan Mao Qing capsules. Quantitative analysis of multicomponent mixture can be done without sample separation. The selection of optimal wavelength pairs is performed through the program with a computer. The method needs no special spectrophotometer and is simple, rapid and easy to operate. The mean recovery was 99.98 +/- 0.53% (n = 12).