摘要:

AbstractCancer is naturally very common, and practical questions about the possibility of radiation-induced harm are often questions about what in other contexts would be called background noise. Central to the question of whether small radiation exposures are carcinogenic is the effect of antenatal radiography. A comparison of singleton and twin births with radiography rates of 10 and 55 per cent respectively showed that radiography must be the main cause of the elevated frequency of malignant disease. In Japanese bomb survivors, most radiation-induced cancer has been found in those irradiated in adult life, less in those irradiated in childhood and adolescence, and least for exposurein utero. Specific biological differences between different kinds of malignant disease in their induction by ionizing radiation are becoming increasingly evident. When dose-response relationships for observed cancer frequencies are to be used as evidence about dose-response relationships for cancer induction, it will always be necessary to allow for the concomitant cell sterilization. When this is done, there is little support for linearity as the method of extrapolation when making predictions about possible effects of low doses but the absence of threshold seems scientifically inescapable. In cellular terms, radiation induction of cancer must be a very rare phenomenon, so rare compared with cell sterilization or mutation induction, that the general corpus of radiobiological understanding may be inapplicable.

DOI:10.1259/0007-1285-48-567-157

出版商:The British Institute of Radiology    

年代:1975

数据来源: WILEY

摘要:

AbstractThree cases of keratosis obturans, which were studied by tomography of the petrous temporal bone, are described. The widening of the deep bony part of the external auditory canal by pressure erosion of an impacted benign slowlygrowing mass is the key radiological finding. Erosion was so severe as to involve the facial nerve canal in one and the temporo-mandibular joint in two cases. The theories of causation are reviewed. Tomography using elliptical tube movement was valuable in diagnosis, pre- and post-operative management.

DOI:10.1259/0007-1285-48-567-170

出版商:The British Institute of Radiology    

年代:1975

数据来源: WILEY

摘要:

AbstractHypothalamic masses associated with histiocytosis-X may be mistaken for neoplasms. As a result radiation therapy will often be administered rather than chemotherapy, which appears to be the treatment of choice for histiocytosis-X of the hypothalamus. Particularly in young people, the possibility of granulomatous disease should be entertained and biopsy should be considered in the presence of a hypothalamic mass.

DOI:10.1259/0007-1285-48-567-176

出版商:The British Institute of Radiology    

年代:1975

数据来源: WILEY

摘要:

Radiology has played little part in the diagnosis of scrotal swellings in the past. A technique has been developed from that used in mammography to aid the diagnosis of difficult cases. A single Medichrome film is backed by a fine-grain, high-definition screen and these are vacuum packed in a thin opaque polythene envelope. A Machlett, HD 50 Mo tube is used. The exposure factors used are 30 kVp, 12–15 mAs at 70 cm FFD. The skin radiation dose measured by an EIL 37C dose meter and lithium borate sachets is less than 0·3 rad per exposure. The patient is usually positioned in a semi-reclining position with the scrotum resting on the film in its vacuum pack. The X-ray tube is angled 15 deg towards the feet. Usually one antero-posterior view is adequate but a certain degree of ingenuity may be required to overcome variations in build and physique, and oblique views are sometimes taken.Twenty-three patients have now been examined radiologically. There were seven neoplasms and 16 cases of benign conditions. In all these patients the diagnosis was confirmed at operation and on subsequent histological examination.

DOI:10.1259/0007-1285-48-567-179

出版商:The British Institute of Radiology    

年代:1975

数据来源: WILEY

摘要:

AbstractRegional ventilation has been measured in 17 healthy volunteers, and 24 patients with chronic obstructive lung disease during tidal breathing using133Xe.The wash-in and wash-out of133Xe were recorded by a gamma camera interfaced to a small digital computer. Regional ventilation was calculated as the distribution of tidal volume per unit lung volume—a measure of relative ventilation—and from the wash-out curves as the fractional exchange of air per second.Determination of the regional fractional exchange of air showed a significant difference between the patients with chronic obstructive lung disease and normal subjects for all regions. The distribution of tidal volume per unit lung volume did not effect such a clear separation.Significant correlations were found between the wholelung fractional exchange of air in the patients with chronic obstructive lung disease and their FEV1r=0·70, MMFRr=0·70, FVCr=0·56 and FEV1/FVCr=0·57.It is suggested that measurement of regional ventilation as the fractional exchange of air is more realistic than methods that determine relative ventilation or only make use of the early part of the wash-out of133Xe.

DOI:10.1259/0007-1285-48-567-181

出版商:The British Institute of Radiology    

年代:1975

数据来源: WILEY

摘要:

Abstract198Au-gold colloid liver scans and75Se-selenomethionine pancreas scans in 72 patients with extrahepatic obstructive jaundice were assessed by blind marking. They were compared with liver and pancreas scans from 20 control patients and liver scans from 33 patients with diffuse liver disease. 56 per cent of the liver scans in extrahepatic obstructive jaundice showed a filling defect in the hilar region of the liver. This was most frequently seen in the most deeply jaundiced patients, and was reported in 80 per cent of patients with a serum bilirubin greater than 15 mg/100 ml. The liver scan alone cannot distinguish between different forms of extrahepatic obstructive jaundice although severe loss of left lobe uptake appeared to favour a diagnosis of carcinoma of the bile or hepatic ducts.A normal pancreas scan virtually excludes a pancreatic carcinoma as the cause of obstructive jaundice. A pancreas scan showing severely reduced uptake suggests a carcinoma of the pancreas or of the lower end of the common bile duct.

DOI:10.1259/0007-1285-48-567-190

出版商:The British Institute of Radiology    

年代:1975

数据来源: WILEY

摘要:

AbstractThe proliferation kinetics of the transplanted adenocarcinoma 284 of C3H mice from the first to the sixth day after 600 R and from the first to the eighth day after 1,200 R has been studied by repeated labelling of the tumour cellsin vivowith3H-thymidine and measurement of the labelling index and the percentage of labelled mitotic cells. The time course of the post-irradiation synchronization was followed during the first day. Later, the mean generation times of the tumour cells were usually prolonged and the spread of the generation times increased. Three to four days after irradiation, the tumour increased its growth fraction to twice the normal value by triggering resting cells (G0cells) into cycle.

DOI:10.1259/0007-1285-48-567-200

出版商:The British Institute of Radiology    

年代:1975

数据来源: WILEY

摘要:

AbstractThe KHT transplantable tumour of C3H mice has been used as a model tumour for thein vivostudy of hypoxic cell sensitizers. Eleven sensitizers comprising four nitrofuran five nitrobenzene and two nitroimidazole derivatives, which have been shown to be effective on hypoxic mammalian cellsin vitro, have been investigated. Two of these compounds, metronidazole (2-methyl-5-nitroimidazole-1 ethanol) and tinidazole (ethy1 [2-(2′-methyl-5′-nitro-1′- imidazolyl) ethyl] sulfone), showed signs of hypoxic cell-sensitizationin vivowhen given systemically by intraperitoneal injections. In addition, preliminary testing of the nitrobenzene NDPP (p-nitro-3-dimethyl-propriophenone hydrochloride) indicated that when it was injected directly into the tumour and irradiation was completed within ten minutes after injection, appreciable sensitization was obtained. More detailed studies indicated that both metronidazole at 1,500 mg/kg and tinidazole at 750 mg/kg given intraperitoneally gave an enhancement ratio of 1·5 for a chronically hypoxic cell population in this solid tumour in air-breathing mice. Measures of plasma levels of metronidazole and enhancement ratios obtained in the presentin vivosystem seem in relative agreement with thein vitroandin vivoresults of others.

DOI:10.1259/0007-1285-48-567-209

出版商:The British Institute of Radiology    

年代:1975

数据来源: WILEY

摘要:

Intrathoracic histiocytomas are rare lesions, believed to be localised areas of reactive granulomatous inflammation. They nearly always arise in lung parenchyma or pleura. This is the first reported case in which a histiocytoma arising in a major bronchus has been demonstrated radiologically.A.C., an 11-year-old white boy, presented to out-patients with an attack of wheezing with cough and haemoptysis in June 1972. There were no previous chest symptoms and he had no family history of asthma. He was noted to have a few loud rhonchi on deep inspiration. The chest radiograph at that time was normal. At his next attendance four weeks later he reported one further episode of haemoptysis and was still wheezing. Treatment with sodium cromoglycate and orciprenaline elixir was started.

DOI:10.1259/0007-1285-48-567-221

出版商:The British Institute of Radiology    

年代:1975

数据来源: WILEY

摘要:

Pseudoaneurysm of the left ventricle is an uncommon abnormality rarely diagnosed correctly before death. Usually in adults the underlying cause has been found to be severe coronary arterial disease (Hurst, Fine and Keyes, 1963; Bjornsson, 1964; Cone and Hawley, 1964; Roberts and Morrow, 1967, Chesleret al., 1969; Erseket al., 1969; Gobel, Vidsudh and Edwards, 1971) although in one previous case no abnormality was demonstrated by coronary ateriography (Gueronet al., 1973). Other causes include both penetrating (Jamshidi and Berry, 1965) and non-penetrating (O'Reilly, Kazenelson and Spellberg, 1970) chest trauma and rupture of a cardiotomy wound (Bross, 1967). The formation of a pseudoaneurysm carries a poor prognosis but surgical correction is feasible and may favourably alter the outcome, particularly if a correct and detailed anatomic diagnosis can be made prior to surgery (Gueronet al., 1973).This report describes the clinical and radiological features of a unique case of left ventricular pseudoaneurysm formation occurring in a patient without significant coronary arterial disease. The etiologic factor is thought to be rupture of a small preexisting left ventricular diverticulum occurring 36 hours after mitral valvar replacement.A 64-year-old woman presented in 1973 with a history of increasing exertional dyspnoea and orthopnoea. Mitral stenosis had been first diagnosed in 1955 and in 1966 increasing exertional dyspnoea was noted and cardiac catheterisation was performed.

DOI:10.1259/0007-1285-48-567-223

出版商:The British Institute of Radiology    

年代:1975

数据来源: WILEY