Practice Essentials. Perinatal asphyxia, more appropriately known as hypoxic-ischemic encephalopathy (HIE), is characterized by clinical and laboratory evidence of acute or subacute brain injury due to asphyxia. The primary causes of this condition are systemic hypoxemia and/or reduced cerebral blood flow (CBF) (see the image below).
Chondrichthyes (/kÉnËdrÉªkÎ¸É¨.iËz/ ; from Greek ÏÎ¿Î½Î´Ï- chondr- 'cartilage', á¼°ÏÎ¸ÏÏ ichthys 'fish') is a class that contains the cartilaginous fishes: they are jawed vertebrates with paired fins, paired nares, scales, a heart with its chambers in series, and skeletons made of cartilage rather than bone.he skeleton is cartilaginous. The notochord, which is present in the young, is gradually replaced by cartilage. Chondrichthyes also lack ribs, so if they leave water, the larger species' own body weight would crush their internal organs long before they would suffocate.
Sharks, skates, rays, and even stranger fish make up the Chondrichthyes, or cartilaginous fish.. First appearing on Earth almost 450 million years ago, cartilaginous fish today include both fearsome predators and harmless mollusc-eaters (harmless, that is, unless you are a mollusc).embers of the Chondrichthyes all lack true bone and have a skeleton made of cartilage (the flexible material you can feel in your nose and ears). Only their teeth, and sometimes their vertebrae, are calcified; this calcified cartilage has a different structure from that of true bone.