Researchers at UCLA Medical Center in Los Angeles， California found that a 12-minute bed-side visit with a dog can help reduce anxiety levels by 24percent in heart failure patients， compared to a 10percent drop when patients had a visit from a human volunteer， and no drop in patients who had no visit． Results of the 76-patient study were presented last week at the American Heart Association's yearly Scientific Sessions in Dallas， Texas． The study was supported by the Pet Care Trust Foundation， a non-profit（非赢利）organization which promotes human-animal interaction and connection． In the study， effects of dog and volunteer visits were compared with those of volunteers only， and with patients who had no visits and stayed at rest． Heart pressures were monitored and patients were asked to answer a list of anxiety assessment questions before and after the visits． Although critical pressure measures also fell， suggesting improved heart function， the most obvious reaction was seen in anxiety levels． "The first thing you notice is that the patient's facial expression， changes to a smile and the stress of the world seems to be lifted off their shoulders，" study author Kathy Cole said． Feelings of disappointment and helplessness are common among heart patients， Cole said， and just three nights in a hospital is enough to make some patients feel anxious and uncomfortable． During the visit， the furry friend is allowed to lie on the bed next to the patient with its head within two feet of the patient's． Most patients petted the dog， while others talked about the dog with human volunteers in conversation． Dogs used in the study are specially trained animal-assisted therapy dogs that go through a series of trainings， assessments and certifications（认证）to qualify as therapy dogs． There are different kinds of dogs． Researchers used everything from Bernese mountain dogs to small schnauzers． However， a dog doesn't have to be specially trained to have a calming effect on a person． In fact， the animal doesn't even have to be a dog in order to help． "As long as the animal has meaning to the patient， or a relationship with the patient， it can help calm the patient，" Cole said．（1）We learn from the text that heart patients benefit most from visits by ____ ．A． a volunteer on his own B． a well-trained dog aloneC． a non-profit organization D． a volunteer with a dog（2）The study shows that， for heart patients， ____ ．A． their recovery depends on contact with animalsB． their heart pressure reduces if they stay at restC． their contact with animals improves their conditionD． their anxiety is reduced if they stay longer in hospital（3）According to Cole， the change of patients' expression on the face indicates that ____ ．A． they are mentally comfortedB． they are happy with the experimentC． their treatment time may be shortenedD． their heart function is returning to normal（4）This report concentrates on ____ ．A． the treatment of heart diseaseB． the cure power of animalsC． the relationship between dogs and humans D． the promotion of human-animal interaction