Word: pellucida
(lookup in dictionary)
(lookup stats)
Dates: all
Sort By: most recent first
(reverse)
Finally, after a third failure, they tried a different approach: doctors retrieved a fresh batch of eggs, and this time they used assisted zona hatching, in which the egg's membrane, known as the zona pellucida, is chemically weakened so sperm can penetrate more easily. (Another way to do this is to drill a tiny hole in the egg; both methods are less tricky than full-fledged ICSI.) Their son, Eric Richard, was born in October...
...first step in development, the scientists quickly separated the cells, creating two different embryos with the same genetic information. (This sometimes happens naturally inside a mother, and the result is identical twins.) In the process, though, the researchers had to strip away an outer coating, called the zona pellucida, that is essential to development. Then came the trickiest part of the procedure. Over the years, Hall had been working with a gel derived from seaweed that could serve as a substitute for the zona pellucida. When Hall put the artificial coating around the cloned embryos, they began to grow...
...latest clue in the mystery of implantation was hit upon by scientists working on a completely different problem: lazy sperm. Some sperm lack the ability to penetrate the egg's outer membrane, or zona pellucida, often as a result of old testicular injuries or early exposure to toxic chemicals. Several methods have been devised to give these sperm a boost, including microinjection (the sperm is inserted directly into the egg by means of a microscopic needle) and partial zona drilling (a tiny hole is made in the egg's protective shell...
| 1 |