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Data are presented on a group of cases of primary carcinoma of the bladder, detailing red cell surface blood group antigenic phenotypes, serum haptoglobin phenotypes, and some red cell isoenzyme phenotypes. Account is taken of the stage of the disease at presentation. The results are compared with corresponding phenotype frequencies in groups of presumed healthy persons originating either in Yorkshire or County Durham. Differences in relative incidences were found in the haptoglobin, phosphoglucomutase (PGM), and some other systems. These are both differences between all cases and controls and between particular stages at presentation and controls.  相似文献   
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A proportionate mortality study of deceased white male workers in the pattern and model making trades was conducted. Death certificates were obtained for 1257 death benefit-eligible members of the Pattern Makers' League of North America who had died in the years 1972-1978, and age-adjusted proportionate mortality was calculated using 1975 United States white male death rates. For the entire nationwide union, statistically significant excess proportions of deaths were observed due to colon cancer (proportionate mortality ratio, PMR = 167) and to brain tumors (PMR = 211). A statistically significant excess proportion of deaths due to colon cancer (PMR = 163) and to leukemia (PMR = 200) were observed among the members of the predominantly wood shop locals. Nonsignificant excess proportions of cancer deaths occurred at a number of other anatomical sites. Predominant occupational exposures included wood and plastic dusts and epoxy resins in wood shops and cutting oil mists and solvent vapors in the metal shops. These results suggest the need for better work practices in this industry while more definitive studies are completed.  相似文献   
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The mechanical properties of human extraocular muscles have recently been described. This allows one to use the force-balance equation of mechanics to solve for the complete mechanical state of all six extraocular muscles and the passive orbital tissues in any eye position. This includes each muscle's force, length, innervation, and unit action vector, which describes how its force is distributed to act horizontally, vertically, and in torsion. Most important, this calculation method allows one to predict the tropias that occur in an eye subject to any imaginable form of peripheral pathology. It also permitts, by calculation, an estimation of the correction that might be expected from any sort of muscle surgery. The tight lateral rectus syndrome is used to illustrate the application of the method in diagnosis and surgery. It also offers, for the first time, a quantitative estimate of the multitude of ways in which muscles can interact and interfere with each other when they hold the globe. Two of the results are interesting: because muscles have different lengths and sizes, their innervational participation in a movement can appear to be quite different than their mechanical participation. From an innervational standpoint, the vertical recti and obliques participate equally in vertical gaze. Muscles interfere with each other a good deal and necessitate changes of innervation to counteract these cross-couplings. This causes unexpected dependencies of innervation on eye position and leads, for example, to the fact that the superior rectus innervation in up gaze is just as large in adduction as in abduction.  相似文献   
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