RESUMO
This paper reports the existence of mast cells in an epithelial location in the gallbladders of both cattle and sheep. The histochemical studies performed on these cells showed that their cytoplasmic granules contain heparin and biogenic amines in both species. Optical- and electron microscopic observations demonstrated that, in both species, mast cells from the connective tissue of the gallbladder diapedese across the basal lamina and migrate through the epithelium all the way to the luminal surface, and that a degranulation process takes place during this migration. The biochemical results showed a correlation between the number of mast cells present in the epithelium and the amount of heparin detected in the different regions of the gallbladders of the species studied. Unusually high contents of heparin were found in both cattle and sheep gallbladders, suggesting that they should be studied as possible commercial sources of this polimer.
Assuntos
Vesícula Biliar/anatomia & histologia , Mastócitos/ultraestrutura , Animais , Aminas Biogênicas/análise , Bovinos , Grânulos Citoplasmáticos/ultraestrutura , Epitélio/ultraestrutura , Fluorescência , Glicosaminoglicanos/análise , Microscopia Eletrônica , Microscopia Eletrônica de Varredura , OvinosRESUMO
This paper reports the existence of granulated cells in the bovine gallbladder epithelium. The histochemical studies performed on these cells showed that their cytoplasmic granules contain heparin. Optical- and electron microscopic observations demonstrated that these mast cells migrated from the adjacent connective tissue, and crossed the basal membrane in order to enter the epithelium and reach the luminal surface.
Assuntos
Grânulos Citoplasmáticos/fisiologia , Vesícula Biliar/ultraestrutura , Mastócitos/fisiologia , Animais , Bovinos , Fracionamento Celular , Movimento Celular , Cães , Epitélio/ultraestrutura , Glicosaminoglicanos/isolamento & purificação , Heparina/isolamento & purificação , Técnicas HistológicasRESUMO
The progressive fall in the status and numbers of general practitioners has produced a dangerous void in the field of comprehensive medical care. The Millis Commission and other national study committees have recommended that family practice be made a board-certified specialty in order to restore the status and numbers of family physicians. The scope of family practice that is envisioned, however, would be so restricted in depth as to raise serious doubts that sufficient medical graduates would be attracted to careers in this new specialty. Better training in broadly-based general or family practice-rather than a specialty board, per se-is the only realistic way to elevate status and attract more medical students to this field.
