A small piece of fish each day may keep the heart doctor away．That's the finding of a scientific study of Dutch men in which deaths from heart disease were more than 50 percent lower among those who consumed at least an ounce（盎司）of salt water fish per day than those who never ate fish.
The Dutch research is one of three human studies that hold the belief that eating fish can provide health benefits, particularly to the heart. Heart disease is the number-one killer in the United States, with more than 550,000 deaths occurring from heart attacks each year．But researchers previously have noticed that the incidence （发生率） of heart disease is lower in cultures that consume more fish than Americans do．There are fewer heart disease deaths, for example, among the Eskimos of Greenland, who consume about 14 ounces of fish a day, and among the Japanese, whose daily fish consumption averages more than 3 ounces.
For 20 years, the Dutch study followed 852 middle-aged men, 20 percent of whom ate no fish. At the start of the study, the average fish consumption was about two-thirds of an ounce each day with more men eating thin fish than fatty fish.
During the next two decades, 78 of the men died from heart disease．The fewest deaths were among the group who regularly ate fish, even at levels far lower than those of the Japanese or Eskimos．This relationship was true regardless of other factors such as age, high blood pressure, or blood cholesterol （胆固醇） levels.
64．Which of the following is NOT true according to the passage?
A．The Dutch research has proved that eating fish can help to prevent heart disease.
B．Heart doctors won't call at your house so long as you keep eating fish each day.
C．Among all the diseases heart disease is the most dangerous in America.
D．There is a low incidence of heart disease in Japan and Greenland.
65．The underlined phrase "this relationship" refers to the connection between ______and the incidence of heart disease.
A．regular fish-eating B．the amount of fish eaten
C．the kind of fish eaten D．people of different regions
66．The passage is mainly about ______.
A．the high incidence of heart disease
B．the great changes in people's diet
C．the fish consumption in some countries
D．the effect of fish eating on people 's health
67．How many lives could probably be saved each year in the United States by eating fish according to the Dutch study?
A．152,000． B．110,000． C．275,000． D．550,000.