九江哪里有印刷厂:stem cell lines 是什么？

stem cell lines 干细胞系
干细胞系就是拥有分化能力的细胞，理论上在特定的条件下可以分化为任何体细胞。

cell line 细胞系， 就是可以在试验室培养的，可以储存的纯化的具有某些特定基因特征的细胞。

现在stem cell research 很热门。

干细胞的轮廓

外形,轮廓[P1]
The new car has very sleek lines.

好象是胚胎的干细胞线吧

stem cell lines 干细胞系
干细胞系就是拥有分化能力的细胞，理论上可以分化为任何体细胞。

干细胞系

Researchers chafing under President Bush's restrictions on human embryonic stem-cell research will have free access to 17 new cell lines provided by a team of academic scientists.
The new lines were created from frozen embryos by scientists led by stem-cell researcher Douglas Melton of Harvard. The research was financed by the Juvenile Diabetes Foundation and the Howard Hughes Medical Institute.

Melton is a critic of Bush's stem-cell policy. In 2001, the president restricted National Institutes of Health funding to a limited number of existing cell lines.

Other critics have been more vocal since the last breakthrough in stem cell research took place outside of the United States, which had been a leader in the field. South Korean researchers announced last month that they have created a stem cell line from a cloned human embryo.

Stem cells are a kind of master cell and embryonic stem cells have the potential to grow into any kind of cell or tissue. Researchers see such cells as a new approach to creating rejection-free transplant tissues for people suffering ailments such as Alzheimer's, diabetes and spinal injury.

Opponents decry the destruction of human embryos required to produce the stem cells.

"For me, these cells mean we now have easy access to materials to make medical advances," says Melton. His team started with 344 donated frozen embryos created at fertility clinics through in-vitro fertilization. From those, 17 lines, or colonies, of stem cells were successfully grown in petri dishes.

Researcher John Gearhart of Johns Hopkins University calls the creation of the new lines a "tour-de-force" in a commentary accompanying the report in an upcoming issue of the New England Journal of Medicine. Gearhart notes the new cells are free, tolerant of antibiotics and quick-growing in some cases, unlike the NIH-approved cell lines. Melton says the new cells are better and more accessible than those in the NIH-approved lines.

The ever-growing cells can be sent to many researchers. But there is the danger of defects after a long period of duplication, which is why scientists want new lines.

A New England Journal editorial called for adding the new cells to the federal registry, which now lists only 15 cell lines available for funding. "There is too much suffering that may be remediable through the therapeutic application of this new approach to place stem cell lines off limits," write journal editors Elizabeth Phimaster and Jeffrey Drazen.

Melton criticized the "chilling effect" that the federal funding ban has had on stem cell research.

James Battey, head of the NIH stem cell task force, defended his agency, saying the new cells "are no better or no worse than cells on the registry." He says that the number of researchers capable of handling stem cells is the true limiting factor on such research, not the funding ban.

Although Bush had said that about 60 lines would be available to researchers, a February NIH summary sent to Reps. Henry Waxman, D-Calif. and Louise Slaughter, D-N.Y. says the "best case scenario" is that 23 lines will eventually be available.