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Showing papers by "University of Lisbon published in 1972"


Journal ArticleDOI
TL;DR: The results of this investigation suggest that local human “cancerisation” can occur and the radiation-leukaemia “risk” estimates which can be derived are important contributions to the sum of available human radiation risk data on leukaemia.
Abstract: A study was made of Portuguese who had, been injected with the radioactive contrast medium “Thorotrast” between 1930 and 1955; a control population matched for age and sex but injected with a non-radioactive contrast medium served for comparison. The study showed a gross excess, primarily in the liver, of the nearly “thorotrast specific” haemangioendotheliomata; there were a large number of other “local” lesions and tumours at the site of thorotrast injection and retention. Two and possibly three primary bone tumours had been observed in the thorotrast population. That was excessive but represents a much smaller incidence and risk than had been predicted. The incidence of lung cancer must be regarded as equivocal owing to the small numbers and lack of information on tobacco usage.

16 citations


Journal ArticleDOI
TL;DR: A new granuloma of this type related to wounds produced by the stubble of wheat is described, taking into consideration its localization in the lower limbs, the wounds caused by stubble, and the identification of intracellular plant material in thegranuloma.
Abstract: Summary.— The introduction into the skin of chemical substances or organic matter can produce granulomata of sarcoid type. A new granuloma of this type related to wounds produced by the stubble of wheat is described. The diagnosis of this lesion is easy, taking into consideration its localization in the lower limbs, the wounds caused by stubble, and the identification of intracellular plant material in the granuloma. A host factor of probable immunological nature is suggested. There is a similarity between these sarcoid granulomata of the skin and some epithelioid granulomatous lesions of the lung due to the inhalation of chemical substances and organic matter, known as “extrinsic allergic alveolitis”.

9 citations


Book ChapterDOI
01 Jan 1972
TL;DR: In this article, the Gumbel and Frechet distributions are derived from the basic notions of order statistics and the extremes of an univariate independent sample are derived, and the asymptotic behavior of the extremes is considered.
Abstract: From the basic notions of order statistics, the extremes of an univariate independent sample are derived. The asymptotic behavior of the extremes is considered and the three forms developed, of which the Gumbel and Frechet distributions are emphasized. Methods of estimation and prediction of parameters of both the Gumbel and Frechet distributions are presented as the underlying statistical decision related to some tests, sequential analysis and graphical procedures.

9 citations


Journal ArticleDOI
TL;DR: In this paper, a surface-barrier detector and a NaI (Tl) scintillation counter were used to measure the fluorescence in radium and uranium x-rays.
Abstract: Fluorescence (${\ensuremath{\omega}}_{2}$), Auger (${a}_{2}$), and Coster-Kronig (${f}_{23}$) ${L}_{\mathrm{II}}$-subshell yields, and the total $L$ fluorescence yield (${\overline{\ensuremath{\omega}}}_{L}$), in uranium and radium have been determined from measurements on $L$ x rays emitted following $\ensuremath{\alpha}$ decay of $^{238}\mathrm{Pu}$ and $^{228}\mathrm{Th}$, respectively. $\ensuremath{\alpha}$ x-ray coincidence techniques employing a surface-barrier detector for the $\ensuremath{\alpha}$ particles and Si(Li) $L$ x-ray spectrometer and a NaI (Tl) scintillation counter, for the $L$ x-rays, were used. The experimental results are ${\ensuremath{\omega}}_{2}=0.423\ifmmode\pm\else\textpm\fi{}0.023$, ${a}_{2}=0.522\ifmmode\pm\else\textpm\fi{}0.056$, ${f}_{23}=0.07\ifmmode\pm\else\textpm\fi{}0.05$, and ${\overline{\ensuremath{\omega}}}_{L}=0.442\ifmmode\pm\else\textpm\fi{}0.012$ for uranium, and ${\ensuremath{\omega}}_{2}=0.415\ifmmode\pm\else\textpm\fi{}0.027$, ${a}_{2}=0.571\ifmmode\pm\else\textpm\fi{}0.084$, ${f}_{23}=0.01\ifmmode\pm\else\textpm\fi{}0.7$, and ${\overline{\ensuremath{\omega}}}_{L}=0.404\ifmmode\pm\else\textpm\fi{}0.024$ for radium.

8 citations


Journal ArticleDOI
TL;DR: The existing bibliography on the vascular aspects of the normal and diseased gallbladder shows that several points of this subject have not been completely and satisfyingly discussed, and the importance of the vascular factor on the ethiology of cholecystitis justifies a deeper insight on the gallbladders vessels.
Abstract: The existing bibliography on the vascular aspects of the normal and diseased gallbladder, inspite so many references found thereof (Eliason, Goldman, Gordon, Hallendorf, Strohl, Thomas), shows that several points of this subject have not been completely and satisfyingly discussed. Particularly the importance of the vascular factor on the ethiology of cholecystitis justifies a deeper insight on the gallbladder vessels. Gordon compared the vascular anatomy of the gallbladder in 35 animals species and grouped the different types of angioarchytecture in three fundamental patterns. He injected the arterial net of the gallbladder with a suspension of barium sulfate and filled gallbladder lumen with a translucent resin. The gallbladder wall was turned transparent with a clearing agent. Photographs were taken and pictures enlarged one and a half times. On the bibliographic searches, also no documentation has been found, comparing the radiologic findings in the oral cholecystography with the microangiographic aspects of the gallbladder.

7 citations