Given a context passage, generate a question from the passage such that its answer is shortest continous span from the passage.
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Question: Sharman Douglas died of bone cancer at New York Hospital in 1996.

Answer: What medical condition killed Sharman Douglas?


Question: The Patriots travelled to the Metrodome for a Monday Night Football showdown with the Minnesota Vikings, who, like the Patriots, boasted an excellent run defense. The Patriots, who took to the air with a spread offense for the entire game, opened with a seven-play, 86-yard strike that ended with a touchdown pass from Brady to wide receiver Reche Caldwell. Their next drive was for 93 yards which resulted in a 23-yard Gostkowski field goal. And just before halftime the Patriots moved 74 yards in 11 plays to take a 17-0 lead on a nine-yard scoring toss to tight end Benjamin Watson. The only Vikings score of the game came on a 71-yard punt return by Mewelde Moore in the third quarter; Laurence Maroney immediately answered on the ensuing kickoff, with a 77-yard return to Minnesota's 21-yard line, his second return of over 70 yards in as many weeks. The Patriots' lead grew to 17 after a seven-yard touchdown reception by Brown with 9:03 in the third quarter and then became 31-7 with a touchdown catch by Jackson. The Patriots defense also intercepted four passes from quarterbacks Brad Johnson and Brooks Bollinger. On Bollinger's first drive after relieving Brad Johnson he was sacked three times in a row for a net loss of 23 yards. With their fourth straight victory, the Patriots advanced to 6-1.This was the Patriots' third and final game played in the Metrodome.

Answer: Which team scored more touchdowns, the Patriots or the Vikings?


Question: Since reports that precursor cells in the adult subventricular zone (SVZ) contribute to regenerative neuro- and gliogenesis in CA1, we wondered whether a similar route of migration might also exist under physiological conditions. Permanent labeling of SVZ precursor cells with a lentiviral vector for green fluorescent protein did not reveal any migration from the SVZ into CA1 in the intact murine brain. However, in a nestin-GFP reporter mouse we found proliferating cells within the corpus callosum/alveus region expressing nestin and glial fibrillary acidic protein similar to precursor cells in the neighboring neurogenic region of the adult dentate gyrus. Within 3 weeks of BrdU administration, BrdU-positive nestin-GFP-expressing protoplasmic astrocytes emerged in CA1. Similar to precursor cells isolated from the dentate gyrus and the SVZ, nestin-GFP-expressing cells from corpus callosum/alveus were self-renewing and multipotent in vitro, whereas cells isolated from CA1 were not. Nestin-GFP-expressing cells in CA1 differentiated into postmitotic astrocytes characterized by S100beta expression. No new neurons were found in CA1. The number of nestin-GFP-expressing astrocytes in CA1 was increased by environmental enrichment. We conclude that astrogenesis in CA1 is influenced by environmental conditions. However, SVZ precursor cells do not contribute to physiological cellular plasticity in CA1.

Answer:
Which intermediate filament (IF) protein can be used as a non-specific marker of the neuronal precursor cells of the subventricular zone?