The Chievitz juxtaparotid organ.

The Chievitz juxtaparotid organ represents a macroscopic longitudinal formation, which is developed from oral cavity ectoderm in its lateral wall. As to its function, the organ probably represents a mechanosensor with different qualities of perception. The information coming from its sensors takes part in different activities of the lateral wall of oral cavity during sucking, swallowing, mastication, speech, protecting reflexes and wall tonus.

Thymectomy and multiple sclerosis: ultrastructural study of an experimental model.

Transmission electron microscopy was performed on specimens of the thymus of rats induced for acute experimental allergic encephalomyelitis (EAE). The ultrastructural alterations of the thymus were progressive and correlated with EAE development. The thymic disorganization was due to a progressive degeneration of both epithelial cells and thymocytes.

Venous drainage of the stomach in the domestic rabbit (Oryctolagus cuniculus f. domestica, breed large Chinchilla) and the domestic cat (Felis catus L. f. domestica).

Two basic patterns of venous drainage of the stomach were found in rabbits. In the first, which is highly prevalent (27 cases-90.0%), the v.

Venous drainage of the stomach in the golden hamster (Mesocricetus auratus) and the guinea pig (Cavia aperea f. porcellus).

Venous drainage patterns of the stomach were studied in 30 golden hamsters (Mesocricetus auratus) and in 30 guinea pigs (Cavia aperea f. porcellus). In golden hamsters the most frequent group had a v.

Nerve fibers--mast cells correlation in the rat parietal pleura.

Our results show that a morphological correlation exists between catecholaminergic nerve fibers and mast cells in the rat parietal pleura. Mast cells are found in proximity to catecholaminergic nerve fibers. Moreover we have demonstrated that mast cells and nerve fibers in the perivascular areas of rat parietal pleura show the same formaldehyde fluorescence.