In its classic definition, by FranÃ§ois-Louis Ganshof (1944), feudalism describes a set of reciprocal legal and military obligations among the warrior nobility revolving around the three key concepts of lords, vassals and fiefs.
The exact cause of intracardiac echogenic foci remains unclear; however, they appear to be caused by small deposits of calcium in the papillary muscle of the fetal heart.
Pulmonary embolism can cause a focal infiltrate or focal at-. electasis; more commonly, the chest radiograph is normal or. shows multifocal infiltrates or multiple nodules. Pulmonary in-. farcts are always based at a visceral pleural surface, including. fissures.