As heart disease continues to be number-one killer in the United States, researchers have become increasingly interested in (36) the potential risk factors that (37) heart attacks. High fat diets and "life in the fast lane" have long been known to contribute to the high (38) of heart failure. But according to new studies, the list of risk factors may be (39) longer and quite surprising.
Heart failure, for example, appears to have seasonal and (40) patterns. A higher percent age of heart attacks occur in cold weather, and more people experience heart failure on Monday than on any other day of the week. In addition, people are more (41) to heart attacks in the first few hours after waking. Cardiologists first observed this morning (42) in the mid-1980s and have since discovered a number of possible causes. An early-morning rise in blood pressure, heart rate, and concentration of heart (43) hormones, plus a reduction of blood flow to the heart, (44) .
In other studies, both birthdays and bachelorhood have been implicated as risk factors.
Statistics reveal that (45) And unmarried men arc more at risk for heart attacks than their married counterparts. (46) .
【参考答案】
heart attack rates increase in the few days before and afte......