RESUMEN
The plateau is a special environment with low air pressure and low oxygen content. The average altitude of Qinghai-Tibet is 3,500 m, and the atmospheric oxygen partial pressure in most areas is lower than 60% of that at sea level. In order to adapt to the plateau low-oxygen environment, the human body has developed corresponding physiological structure and functions adjust. In the present review, the regulation mechanism of cerebral blood flow (CBF) under high-altitude environments was elaborated in eight aspects: the arterial blood gas, endogenous substances in the nerve and blood, the cerebral neovascularization, the hematocrit, cerebral auto-regulation mechanism, cerebrovascular reactivity, pulmonary vasoconstriction, and sympathetic automatic regulation, aiming to further explore the characteristics of changes in brain tissue and cerebral blood flow in a hypoxic environment.
Asunto(s)
Circulación Cerebrovascular , Hipoxia , Adaptación Fisiológica , Altitud , Circulación Cerebrovascular/fisiología , Humanos , OxígenoRESUMEN
OBJECTIVE: To understand the epidemiological characteristics of essential hypertension in the northern and western areas of China. METHODS: A community-based sampling survey. RESULTS: Rates of awareness, treatment and control were 78.6%, 59.7% and 5.9%, respectively. About half of the diagnosed and treated patients took antihypertensive medicine irregularly before the survey was carried out. CONCLUSION: It is necessary to carry out education, prevention and control on hypertension and to establish a series of standards for the management and treatment on cases of hypertension.