Given an abstract of a paper, generate a title for this paper such that conveys the key focus of the paper.

Ex Input:
Abstract: Seventy-five patients, 80-90 years old, each having approximately three associated diseases, underwent a total of 104 gastrointestinal endoscopies. Of these, 73 were upper (29 emergencies) and 31 lower endoscopies (21 were rigid sigmoidoscopies). There were two very mild short-lived complications; vomiting and bleeding. We found 16 gastric ulcers, 16 duodenal or pyloric ulcers, and 11 cases of esophagitis. Bleeding duodenal (8) or gastric (4) ulcers and polyps or malignant tumors (7) were seen less often. In 34 of 68 lesions the endoscopic and x-ray findings were the same. In the other 34 there were 10 endoscopic failures to identify colonic diverticula, hiatus hernia, and gastroesophageal reflux that were seen radiologically. In 24 patients, diagnoses were not made radiologically, but were recognized at endoscopy. The safety and accuracy of endoscopy in the old and sick does not differ from that in younger patients.

Ex Output:
Gastrointestinal endoscopy in octagenarians.

Ex Input:
Abstract: It has been suggested that the risk of breast cancer is increased by oral contraceptive use before the first birth, or by use before age 25, particularly if certain formulations are used. These hypotheses were evaluated in a hospital-based case-control study. A total of 521 patients under age 45 with breast cancer were compared with 521 controls matched for age, time of interview, and geographic area. Oral contraceptive use before the first birth was reported by 155 patients and 137 controls. With allowance for confounding by multivariate analysis, the estimated relative risk was 1.0 (95% confidence interval, 0.6-1.5). The estimate was 1.0 (0.2-3.9) for any use among nulliparous women and 0.6 (0.3-1.3) for use before the first birth among parous women. Use before age 25 was reported by 145 patients and 141 controls, and the multivariate relative risk estimate was 1.0 (0.7-1.6); the results were similar when use of specific formulations was examined. For oral contraceptive use before either the first birth or age 25, the relative risk estimates were compatible with 1.0 for use of five or more years' duration or an interval since first use of at least 15 years. There was also no evidence of an increased risk in any subgroup including those at increased underlying risk because of factors such as a family history of breast cancer or a history of cystic breast disease. The findings suggest that, up to age 45, the risk of breast cancer is not influenced by the use of oral contraceptives before the first birth or before age 25 even if the use lasted for five or more years.

Ex Output:
Breast cancer risk in relation to early oral contraceptive use.

Ex Input:
Abstract: Double filtration plasmapheresis (DFPP) is a technique devised in an attempt to selectively remove pathogenetic macromolecules such as antibodies, immune complexes or viscosity-increasing substances directly from blood. In order to realize the differential filtration principle, two filters, one for separation of plasma and another for fractionation of plasma components, are installed in an extracorporeal circulation line. Selective separation of the plasma components is dependent on the filtration property of the two filters. Clinical experiences evidence the usefulness of this technique in regard to conservation of human blood products for supplementation.

Ex Output:
Selective removal of pathogenetic macromolecules directly from whole blood by double filtration technique.