instruction:
Given an abstract of a paper, generate a title for this paper such that conveys the key focus of the paper.
question:
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.
answer:
Breast cancer risk in relation to early oral contraceptive use.

question:
Abstract: We have developed a new cellulose membrane in which the active hydroxyl and carboxyl groups of the original cellulose fibers are masked with cationic synthetic polymers. The membrane was shown by in vitro and clinical tests to affect the activation of the complement system very little, and it retains the high dialysis efficiency, good tolerance to steam autoclave sterilization, and economical production cost characteristics of the original cellulose membrane. It thus appears that the new cellulose provides the optimum combination of qualities needed in a hemodialysis membrane.
answer:
Development of a regenerated cellulose non-complement activating membrane for hemodialysis.

question:
Abstract: Virus-associated hemophagocytic syndrome has been recently identified as a benign, reactive histiocytic proliferation distinct from Rappaport's malignant hystiocytosis. Other etiologic agents, including different bacteria, have also been identified. Three autopsy cases of hemophagocytic syndrome associated to acute tuberculous sepsis are presented. Benign histiocytic proliferation with striking hemophagocytosis was present in a disseminated, multisystemic pattern in all three cases. A relationship between systemic histiocytic proliferation and an anergic status in these patients is suggested.
answer:
Tuberculosis-associated hemophagocytic syndrome. A systemic process.