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

Example Input: Abstract: High-volume intravenous urography was performed in 63 women with surgically proven endometriosis. Subtle abnormalities were found in 15.9% of these women. No patient had urologic symptoms, and there was no evidence of hydroureter or ureteral obstruction on the IVP. Long-term follow-up study will be required to determine whether or not these lesions will progress and cause ureteral obstruction.
Example Output: Ureteral abnormalities in women with endometriosis.

Example Input: Abstract: When bovine parathyroid cells in culture are exposed to the active vitamin D metabolite 1,25(OH)2D3, a significant decrease in the steady-state levels of pre-proparathyroid hormone (pre-proPTH) mRNA occurs. The possibility that the fall in specific mRNA is due to a decrease in rate of transcription of the PTH gene was examined in this study. In the presence of 1,25(OH)2D3, there was a rapid and steady decline in PTH gene transcription rate which fell to a minimum of 10-15% of control at 24 h. The effect was observed at physiological levels (10(-11)M) and was also fully reversible.
Example Output: Suppression by 1,25(OH)2D3 of transcription of the pre-proparathyroid hormone gene.

Example Input: Abstract: This paper reports the Authors' 8 year experience in the clinical use of charcoal hemoperfusion as a means to reduce the weekly time of treatment in chronic uremic patients. Two different programmes were applied. Programme A (34 patients) which involved substituting the 3 procedures per week of standard dialysis (4 hours duration each) by 2 procedures of combined hemodialysis and hemoperfusion, again of 4 hours duration each. Programme B (18 patients) which involved substituting the 3 procedures per week of 4 hours duration by 3 procedures of 3 hours each, 2 of combined hemodialysis and hemoperfusion, 1 of conventional dialysis. The net weekly reduction was 33% for Programme A and 25% for Programme B. The efficacy of the two Programmes was evaluated by clinical, hematochemical, nutritional and instrumental parameters.
Example Output:
Hemoperfusion in reduced-time programmes for chronic uremia. Long-term results.