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A total of 128 primary mammary tumors (66 of them malignant) occurred in 35 female beagles injected with {sup 226}Ra at eight dose levels ranging from 0.2 to 440 kBq/kg body mass as young adults, while a total of 156 mammary tumors (57 of them malignant) were seen in 46 female control beagles not given any radioactivity. Sixty-three of 65 control dogs and 59 of 61 dogs given {sup 226}Ra survived the minimum age for diagnosis of mammary tumors of 3.75 years. Based on the observed age-dependent tumor incidence rates in the controls and on the corresponding number of dog-years at risk, the total number of observed malignant tumors in the radium group was statistically greater than the number of expected malignant tumors (66 observed vs 34 expected, P < 0.005). There was no such difference for the benign tumors. Cox regression analysis indicated no increased risk for the first tumor occurrence in irradiated dogs. Cox regression analysis of the multivariate risk sets showed no significantly increased risk for the occurrence of benign tumors but a statistically higher risk of 1.66 with a confidence interval of 1.15-2.40 for the occurrence of malignant tumors. The increased risk was dependent on dose,more » but a dependence on the frequency of previous occurrence of mammary tumors could not be confirmed. Censoring ovariectomized dogs at time of surgery decreased the relative risks slightly but did not alter the significance. Exposure to diagnostic X rays with cumulative exposures below 0.2 Gy had no effect on tumor formation. It is unknown whether the increased risk for malignant mammary tumors was due to some initial deposition of radium in sensitive tissue, a possible irradiation of fatty mammary tissue from transient radon {yields} polonium deposition, or a general effect of the overall radium deposition on the immune system of the dogs that lowered their resistance to formation of mammary tumors. 27 refs., 5 figs., 4 tabs.« less

An animal model of tubal sterilisation would be valuable in order to examine the problem of severe damage of the tubal wall and to study the criteria for optimal anastomosis. In a preliminary experimental group the Fallopian tubes of 30 rabbits were ligated at the isthmic segment. Specimens of the ligated portion and other tubal segments have been investigated by light microscopy and scanning and transmission electronmicroscopy one, four and twelve weeks following the ligature. Changes in the Fallopian tubes following the ligature were limited to the ligated portion. The morphological findings consisted of a flattening and decrease of differentiation of the mucous epithelium, and of a slight scarring in the tubal wall and in the subperitoneal tissue within the constricted segment. Tubal ligation at the isthmic segment provides good conditions for refertilisation, following resection of the altered portion and microsurgical anastomosis.

Two types of summary measures of joint disease were evaluated in 2 controlled clinical trials in rheumatoid arthritis patients. One measure was based solely on the clinical/biologic judgment approach; the other combined this methodology with statistical approaches using reliability and factor analyses. "Signal joint" indices, summarizing disease activity in 2-5 key joints, were found to be insensitive to deterioriation of nonsignal joints. Therefore, they are not recommended as replacements for the complete articular survey in rheumatoid arthritis. A reduced version of the complete articular survey was found to be desirable based on its validity, reliability, accuracy, precision, and sensitivity to active drugs. Its sensitivity can be slightly higher or lower than that of the full joint survey.

Es ist bekannt, das Lebertransplantate immunologisch gunstiger sind als andere Organe. So kann ein Leberempfanger beim Schwein und der Ratte ohne Immunsuppression unbegrenzt uberleben. Einige Autoren meinen, das Leberextrakt einen inhibierenden Effekt auf die cellulare Immunreaktion zeigt (1), andere haben darauf hingewiesen, das die Antigenitat der Leber relativ gering ist (2). Diese Faktoren sollten fur das gunstige Verhalten der Lebertransplantate verantwortlich sein. Trotzdem ist es noch unklar, welcher Mechanismus direkt auf die Verlangerung des Uberlebens von Lebertransplantaten einwirkt.