instruction:
Given an abstract of a paper, generate a title for this paper such that conveys the key focus of the paper.
question:
Abstract: Prolonged exposure to nitrous oxide produces a recognized neurologic syndrome. We report clinical and electrophysiologic studies of nervous system involvement in a 25-year-old student who abused nitrous oxide. He developed signs of a sensorimotor polyneuropathy and of myelopathy. Routine blood studies, CSF examination, and myelogram were normal. Clinical electrophysiologic studies were performed serially. Nerve conduction studies demonstrated reduced amplitude and slowed sensory potentials, and mildly prolonged late responses. Sensory evoked potentials revealed prolonged latency of scalp-evoked potentials from tibial nerve stimulation with normal median nerve values. The foveal visual evoked potential was delayed in the right eye, with normal visual acuity, funduscopic examination, and spatial contrast sensitivity. Repeat electrophysiologic studies demonstrated improvement. Nitrous oxide produces multifocal reversible dysfunction within the nervous system similar to that described in patients with vitamin B12 deficiency.
answer:
Nitrous oxide: clinical and electrophysiologic investigation of neurologic complications.

question:
Abstract: We treated 11 psoriatic patients with topical 1 alpha,24-dihydroxycholecalciferol, a new synthetic analogue of active vitamin D3. In 10 of 15 tests the lesions cleared completely within 1-4 weeks, although some relapses occurred shortly after cessation of treatment. There were no side-effects. We suggest that 1 alpha, 24(OH)2D3 merits further investigation as a potentially useful topical therapy for psoriasis.
answer:
Successful treatment of psoriasis with topical application of active vitamin D3 analogue, 1 alpha,24-dihydroxycholecalciferol.

question:
Abstract: To better understand declining autopsy rates, data have been gathered prospectively on 1080 consecutive deaths over six years among patients admitted to a medical intensive care/coronary care unit. Overall autopsy rate was 36%. Autopsy rates declined sharply with age from 60% for those aged 16 to 34 years to 23% for those 85 and over (P less than .001). The highest rates by diagnosis were aortic aneurysm (70%), hepatic failure (52%), heart rhythm disturbance (48%), pulmonary embolism (45%), and sepsis (41%). Patients receiving major procedures had a significantly higher autopsy rate (38 versus 29%, P less than .05) but rates bore little relation to prognoses given at admission by house officers, suddenness of death, sex, marital status or year of admission. Even among intensively treated patients, autopsy rates decline strikingly with age, demanding honest re-appraisal to restore the place of autopsy in medical education, clinical research, and quality of care assessment for an increasingly elderly population.
answer:
Age and the declining rate of autopsy.