21.   No studies linked this drug with the heart valve disease.

22.   Not surprisingly, the study linked various strains of salmonella to a high percentage of food-related illness.

23.   No studies linked this drug with the heart valve damage.

24.   Now, a new study has linked food allergies to the respiratory difficulties that underlie asthma.

25.   Numerous studies have linked it to serious health problems.

26.   Only a few small studies previously linked high cholesterol early in life to heart disease later on.

27.   Other studies have linked aspirin use to protection against cancer of the colon and rectum.

28.   Other studies had linked high levels of homocysteine in the blood to a greatly raised risk of suffering a heart attack.

29.   One study linked coffee with an increased risk of pancreatic cancer.

30.   People with severe sleep apnea have trouble staying awake during the day and are prone to car accidents, and studies have also linked the condition to cardiovascular problems.