All subjects attended the laboratory on one occasion only, for approximately 2 hours.
The subjects attended the laboratory on 4 separate days within one week.
For instance, skin and cartilage could be grown in the laboratory on a synthetic base to form an ear to replace one lost to, say, cancer.
A national accreditation agency placed the laboratory on probation in December after finding procedural and policy violations in drug testing.
A spokesman for the laboratory on the Tropicana job, Site-Blauvelt of Mount Laurel, N.J., said only that the company was cooperating with the investigation.
In addition, a few, in their 30's, are the equivalent of human centenarians, said Dr. Donald K. Ingram, acting chief of the laboratory on experimental gerontology.
Mr. Domenici, who toured the laboratory on Monday with its director, G. Peter Nanos, added, "This entire situation only reinforces that we need to improve the inventory system".
The Harvard-Wisconsin team discovered the receptor for protective antigen by growing cells in the laboratory on a diet that included a mildly mutagenic chemical.
In each study, participants attended the laboratory on consecutive days.
The zinc sulfide precipitate was filtered in the laboratory on 0.45 µm nylon filters (Pall, Nylaflo).
The crew had spotted particles of ammonia drifting away from the laboratory on Thursday.
