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

Example Input: Abstract: Previous studies of the effect of tricyclic antidepressants on left ventricular function in depressed patients with moderate to severe ventricular impairment have focused primarily on imipramine hydrochloride. In a prior study, we found that although imipramine had no effect on ejection fraction as measured by first-pass radionuclide angiography, the treatment could not be tolerated by 50% of the patients because of intolerable drug-induced orthostatic hypotension. Nortriptyline hydrochloride is an effective antidepressant that, in depressed patients without heart disease, causes significantly less orthostatic hypotension than imipramine. To see if this advantage could be safely extended to patients with congestive failure, we measured the effect of nortriptyline on ejection fraction and blood pressure in 21 depressed patients with left ventricular impairment. Ejection fraction was unchanged by nortriptyline treatment, and orthostatic hypotension developed in only one (5%) of 21 patients. Nortriptyline emerges as a relatively safe treatment for depression in patients with left ventricular impairment.
Example Output: Nortriptyline in depressed patients with left ventricular impairment.

Example Input: Abstract: Calcium performs a unique role in biology, achieving biological effects through highly specific interactions with and modulation of target proteins. It has been proposed that calcium-modulated proteins possess a characteristic, evolutionarily related, binding fold, known as the EF-hand. The high-resolution X-ray structure of alpha-lactalbumin reveals a Ca2+ binding fold that resembles an EF-hand only superficially and presumably has no evolutionary relationship with it. However, there is clear homology with the corresponding loop in c-type lysozyme (the 'parent' molecule of alpha-lactalbumin). This study, at 1.7 A resolution, represents one of the most accurate analyses of a calcium binding protein yet reported.
Example Output: Alpha-lactalbumin possesses a novel calcium binding loop.

Example Input: Abstract: Pediatric residency training programs were surveyed to assess current methods of educating house staff to manage pediatric cardiopulmonary resuscitations. Of the 155 programs responding, 96% provide Basic Life Support training, while 79% offer Advanced Cardiac Life Support training, but only 30% provide ongoing education in the form of mock arrests. In general, the availability of the various forms of resuscitation management instruction was not related to either program size or institution needs. The system of training pediatric residents to manage pediatric cardiopulmonary resuscitations at The Johns Hopkins Hospital is outlined.
Example Output:
Current methods of training residents to manage pediatric cardiopulmonary arrests.