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).     

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).     

Allodynia in rats infected with varicella zoster virus—a small animal model for post-herpetic neuralgia

The most common complication of herpes zoster is post-herpetic neuralgia (PHN), which has been defined as severe pain occurring 1 month after rash onset or persisting for greater than 3 months. PHN is classed as a neuropathic pain that is associated with mechanical allodynia where normally innocuous tactile stimuli are perceived as painful. The development of therapies to treat PHN has been hampered by the lack of animal models, which mimic the clinical situation. We have previously reported that varicella zoster virus (VZV) infection in the rat results in mechanical allodynia and thermal hyperalgesia. Here, we report that following VZV infection of the left footpad rats develop a chronic mechanical allodynia, which is present for longer than 60 days post-infection and which resolves by 100 days PI. The model is robust and reproducible with animals consistently developing allodynia by 3 days PI and continuing to present with symptoms for at least 30 days. The reproducible nature of the induction and course of the allodynia allows the use of this model to determine the effect of various compounds on, and to investigate the pathogenic mechanisms underlying the development of VZV-induced allodynia. Comparative studies using HSV-1 show that the induction of the chronic allodynia is VZV-specific and is not a result is of virus replication-induced tissue damage or accompanying inflammation.Therefore, we propose that the rat VZV infection model could prove useful in studying the mechanisms underlying post-herpetic neuralgia.     

Application of reflectance spectroscopy to the estimation of uric acid, urea and glucose: an evaluation of the Ames Seralyzer

An original approach to the measurement of analytes in clinical chemistry has now become available, in which dry reagent strip technology is linked to measurement by reflectance spectroscopy. The present studies have evaluated the performance of the first of these test systems—for uric acid, urea and glucose, in serum—by comparison with conventional liquid chemistry methods. Satisfactory performance in terms of both precision and accuracy was obtained for all three test systems, the current “state-of-the-art” performance criteria being met; the Seralyzer system proved reliable and easy to use in the hands of trained operators. It should find a place as a “Stat” analyser in the laboratory, in specified wards and in Health Centres.