【評論主題】10.下列何者與牛隻飼養於7000英呎以上高海拔區域所出現的病灶無關？(A)肺因性高血壓 (B)皮下水腫 (C)荳蔻肝 (D)左心室肥大

【評論內容】

Although many factors may contribute to the incidence of BMHD, the pathogenesis is directly related to the hypoxic condition that results from high altitude. Pulmonary vascular shunting is a normal physiologic response to hypoxic conditions and is seen in all animals. Strong responses are seen in cattle, horses, and pigs, whereas people, dogs, guinea pigs, and llamas are less responsive. These findings and the high incidence of disease in cattle indicate they are uniquely susceptible. The vasoconstriction mechanism of shunting is a way to divert unoxygenated blood to oxygen-rich regions of the...