A two week old walkout by 7,000 of the 27,000 public sector doctors in Venezuela is wreaking havov on a health care system that has been in steady decline for more than a decade. And no one has felt its effects more keenly than the poor, who rely on inexpensive medical treatment from government-funded hospitals and clinics and account for about 70 percent of the population. But the doctors despair of low pay, aging equipment and dying patients.