51.   A previous study has also shown a similar rate of diagnosis of coeliac disease.

52.   In previous studies no clearly identifiable risk factors for colorectal cancer have been found except age, and family history.

53.   Human papillomavirus have been reported to be associated with the genital tract and extragenital tumours in previous studies.

54.   High molecular weight DNA was extracted from CC-M cells as in previous studies.

55.   This study shows that supplemental oxygen improves oxygen saturation values during upper gastrointestinal endoscopy, which is in keeping with previous studies of both gastroscopy and ERCP.

56.   This study has shown a larger proportion of electrocardiographic changes than previous studies, even though some of these included sinus tachycardia as an arrhythmia.

57.   Previous studies on longterm results of fundoplication were based mainly on questioning patients, with only sporadic endoscopical examination.

58.   Previous studies have attempted to evaluate the severity of duodenogastric reflux and to determine whether specific constituents of duodenal juice are responsible for symptoms.

59.   This confirms the results of previous studies.

60.   According to previous studies, gastric metaplasia is an almost constant finding in patients with duodenal ulceration.