english speaking final exam

for a fleeting time, a day or two at most, all things are possible to an extraordianry group of newly created embryo, called embryonic stem cells. they have capacity to grow into nerves, blood, herat, bone and all the rest.  that embryonic stem cells could be terrifically useful in their unspecialized state as well, not only as a source of cells information, but also as a source of replacement for tissue damaged.

isolating stem cells in their pristine state proved difficult, but two independent team from University of Wisconsin in Madison and in Johns Hopkins annouced that they both had pulled it off. the stem cells can survive in petri dish for along nine month.

the researcher coaxed Wisconsin group to take next step and differentiate into neural, gut, muscle, and bone cells.

because, it is illegal to use the federal money for research that involves human embryo, wisconsin group ang johns hopkins seek finding from Geron Corp, an biotech firm in california.

the source of cells, johns hopkins took from fetused that had been aborted in early of pregnancy. the wisconsin group use blastocysts, cluster of about 140 cells that develop within a week after fertilization.

in principle, stem cells could be used for a vast array of profitable and lifesaving therapies. they could be coaxed into forming heart. they might be turned into neuron to replace brain cells destroyed by alzeimer's. they may someday provide new pancreatic cells to pump insulin into bloodstream of diabetics.

the list goes on to include irtually any disorder that involves the loss of normal cells, such as muscullar dystrophy, spinal cord injury, kidney or lives dieases, and blindness caused degeneration of retina. stem cells colud also provide drug companies with a limitless supply of norml human tissue to testing the toxicity of new drugs. 

at this point, it is not clear whether the isolated stem cells produce literally any tissue in the body or can make a few type that already seen in the lab. if the experiment had been done in mice, the next step would been to test the stem cells' versality by trying to grow an entire mouse. such an experiment would clearly have been unethical with human cells.

Another key question is whether scientists can learn to guide stem cells into specific paths of development. Answering all these questions and turning the answers into useful therapies is a daunting undertaking. unvornately, geron's pocket are not bottomless and the traditional source of funding is unavailable. johns hopkins and wisconsins group had to declare that no federal funds were used in their work.

Title                : The Biological Mother Lode

Author            : Michael D. Lemonick

Date                : November 16, 1998

Source             : Time magazine

next step, I would create ppt to help my presentation ..

I'm getting nervous for speaking test tommorow :

wish me get nice examinier, and wish me luck :')

you too :)

ganbatte :D