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Biomedical subjects

J A Dick

Publications and source records attributed to J A Dick.

17 recordsLinked to original sources
PubMed1992

The significance of irregular opacities on the chest roentgenogram.

Scanty irregular opacities are not uncommonly observed on the chest roentgenogram in the absence of interstitial fibrosis of the lungs. In such circumstances the irregular opacities, when present, tend to be relatively scanty and seldom, if ever, exceed an ILO category of 1/1. They are found in association with cigarette smoking, especially when emphysema is also present. The development of irregular opacities is also related to exposure to various mineral and other dusts, and although their prevalence increases with cumulative dust exposure, in general the type of dust, whether fibrogenic or relatively inert, seems to be of little moment. The presence of irregular opacities remains a troublesome confounding factor in epidemiologic studies of both dust-exposed and nonexposed populations. The morbid anatomic changes that occur in the lungs of nondust-exposed workers and which are responsible for the development of irregular opacities in the chest roentgenogram remain unknown.

Age Factors↗
PubMed1988

Piezo-ceramic lithotripsy of gallbladder stones: initial experience in 38 patients.

The efficacy, safety, and side-effects of a piezo-ceramic system for extracorporeal shock-wave lithotripsy of gallbladder stones were assessed in the first 38 patients treated. Gallstone fragmentation was achieved in 34 patients; 25 required more than 1 treatment session (range 1-5). Extracorporeal shock-wave lithotripsy, conducted without sedation, analgesia, or anaesthesia, was well tolerated by all patients; no patient reported pain or discomfort either during or after the procedure. Side-effects were negligible: transient microscopic haematuria in 2 patients, transiently abnormal liver function tests in 1, and short-lived cutaneous petechiae in 4. Initial experience shows that lithotripsy with this system is effective, safe, and well tolerated.

Ceramics↗
PubMed1988

Irregularly shaped small shadows on chest radiographs, dust exposure, and lung function in coalworkers' pneumoconiosis.

The predominant shapes of small opacities on the chest radiographs of 895 British coalminers have been studied. The aims were to determine whether irregular (as distinct from rounded) small opacities can be identified reproducibly, whether their occurrence is related to dust exposure, and whether they are associated with excess prevalence of respiratory symptoms or impairments of lung function. Six of the doctors responsible for regular radiological surveys of all British coalminers each classified all 895 radiographs twice and independently, using the International Labour Organisation's 1980 classification system. The majority view was that 39 films showed predominantly irregular small opacities, 131 showed predominantly small rounded opacities, and 587 showed no small opacities. Readers' opinions varied about the presence and shapes of shadows on the other 138 films. In general, consistency between readers (and within readers on repeated viewings) was satisfactory. The occurrence and profusion of irregular shadows were related significantly both to the men's ages and additionally to their cumulative exposure to respirable coalmine dust as determined from 15 years' dust monitoring close to where the miners had worked. For any given level of exposure, the average level of profusion of the small irregular opacities was less than the corresponding profusion of small rounded opacities. The prevalence rates of chronic cough and phlegm, and of breathlessness, were higher in those with small irregular opacities than in those with no small opacities (category 0/0), but the differences were not statistically significant after adjustment for other factors including smoking habits. The presence of irregular (but not rounded) small shadows was associated with an impairment in respiratory function averaging about 190 ml deficits in both FEV1 and FVC. These deficits were not explicable in terms of the men's ages, body sizes, and smoking habits and they were in addition to the lung function losses attributable to the miners' dust exposure as such. It is concluded that the presence and profusion of small irregular opacities should be taken into consideration when assessing the severity of coalworkers' simple pneumoconiosis.

Age Factors↗
PubMed1986

Complex urinary undiversion.

Thirty-one previously diverted patients with various complex lower urinary tract problems have been undiverted with simultaneous reconstruction of the anorectum and vagina when these structures were also affected. No patient was denied undiversion on the basis of pelvic pathology. The only contraindications were a lack of motivation and when the patient's general condition, intelligence and mobility made it an unrealistic proposition.

Adolescent↗
PubMed1986

Continence and potency preserving cystoprostatectomy and substitution cystoplasty for patients with bladder cancer.

Fifteen potent men with T3 M0 transitional cell carcinoma of the bladder underwent a technique for cystoprostatectomy designed to preserve the innervation of the distal sphincter mechanism and the corpora cavernosa, and substitution cystoplasty. All patients had previously had radiotherapy. When the neurovascular bundles were seen to be preserved all patients were continent by day (although one had objectively demonstrable stress incontinence) and 60% were potent. Damage to the neurovascular bundles was usually associated with impotence and a degree of stress incontinence, although the latter was correctable by implantation of an artificial sphincter. Cystectomy need not necessarily lead to an abdominal stoma or to impotence.

Aged↗
PubMed1981

Quartz and pneumoconiosis in coalminers.

In a routine survey of 623 miners in one colliery, 21 men, an unusually high number, showed radiological progression of simple pneumoconiosis in spite of generally low exposures to mixed coalmine dust. Comparison of the dust exposures of the 21 men with those of matched controls without pneumoconiosis showed highly significant differences in the proportion of quartz in the mixed dust to which they had been exposed. Quartz exposure may be an important factor in the development and rapid progression of coalworkers' pneumoconiosis. Some indication of the levels of quartz exposure which are likely to be hazardous is given.

Air Pollutants, Occupational↗
PubMed1979

The relationship between coal rank and the prevalence of pneumoconiosis.

As part of the Periodic X-ray Scheme of the National Coal Board (NCB), a comparison is made between the previous and new films of all miners who were face-workers on the former occasion, five years earlier. This assessment is made by distributing the films randomly to all the NCB readers. This paper compares the rank of coal mined in each colliery with each colliery's percentage prevalence of pneumoconiosis of at least ILO category 1 in the films of previous face-workers obtained during the third survey round (1969-73). Of the NCB's 291 collieries in Britain, information enabling a rank classification to be made was available for 250, employing 62 362 face-workers. In these 250 mines a progressive and five-fold increase in prevalence was observed from collieries mining low-rank (bituminous) coal to those mining coal of high ranks (anthracite and high-grade steam and coking coal). A possible reason for this is that, in the past, high-rank collieries may have had the highest mass-concentrations of respirable dust.

Carbon↗