Experimental study on the effects of +Gz. Acceleration under gestational conditions. I. Ultrastructural myocardial lesions.

In the course of a complex experimental study concerning the effects of highly positive acceleration on gestation and development of the neonate, investigations were carried out of ultrastuctural myocardial lesions in the pregnant rat exposed to prolonged gravitational stress (+ 2G). The experimental animals presented various disseminated and partly irreversible myocardial lesions whose pathogeny is discussed.

[Posterior (retrovascular) mediastinocervical goiters].

Three cases are presented of endo-thoracic goiters with posterior, retro-vascular developement, a very rare variety of the mediastino-cervical goiter. The anatomic pathways are described, along which this variety of goiter can migrate inside the thorax, as well as the radiologic signs which allow to make a diagnosis. In view of making a choice of the access route the importance of the diagnosis is particularly stressed, before surgery is attempted.