更多"For the first time, scientists have"的相关试题:
[填空题]For the first time, scientists have profiled specific genetic changes during the aging of experimental animals, a discovery that could aid work to extend life span and preserve health. The study, conducted with mice at the University of Wisconsin, combines a powerful new genetic technique with dietary restriction, the only known way to delay the aging process.
66. ______
Moreover, it reveals how a low-calorie diet, the only known method of slowing aging in several animal species, works at the most basic level to extend life span and preserve health. Such knowledge, used in concert with new technologies capable of rapidly surveying the activity of thousands of genes at once, premises to accelerate the development of drugs that mimic the age-retarding effects of a low-calorie diet, according to the Wisconsin scientists.
The Wisconsin team, led by Tomas A Prolla, a UW-Madison professor of genetics, and Richard Weindruch, a UW-Madison professor of medicine, profiled th
[单项选择]Is this the first time you have traveled by air ()
A. I had many travels by train.
B. Here you are.
C. I like traveling.
D. Yes, it’s very comfortable.
[单项选择]A. It is the first time they have climbed the mountain.
B. They think it is not worth to climb the mountain.
C. They hope to climb the mountain again when they are old.
D. They found it hard to climb the mountain this time.
[简答题]
For the first time in decades, doctors have begun making major changes in the treatment of lung cancer, based on research proving that chemotherapy can significantly lengthen life for many patients for whom it was previously thought to be useless.
The shift in care applies to about 50,000 people a year in the United States who have early cases of the most common form of the disease, non-small-cell lung cancer, and whose tumors are removed by surgery. (46) Many of these patients, who just a few years ago would have been treated with surgery alone, are now being given chemotherapy as well, just as it is routinely given after surgery for breast or colon (结肠)cancer. The new approach has brightened a picture that was often bleak.
"The benefit is at least as good, and maybe better than in the other cancers," said Dr. John Minna, a lung cancer expert and research director at the University of Texas Southwestern Medical Center in Dallas. He said new disco
[单项选择]Scientists have for the first time used cloning to create human embryos that live long enough in a laboratory dish to have their stem cells harvested. The feat could set the stage for physicians to produce cells and tissues, tailored to a patient’s genetic identity that can treat a wide variety of human illnesses. The accomplishment also provides a road map for how to clone a person, an even more divisive undertaking.
The new work, performed in South Korea, represents "a major advance in stem cell research. It could help spur a medical revolution as important as antibiotics and vaccines", says Robert Lanza of Advanced Cell Technology (ACT), a company in Worcester, Mass., that’s also investigating the promising stem cell strategy called therapeutic cloning.
"However, now that the methodology is publicly available", Lanza adds, "I think it is absolutely imperative that we pass laws worldwide to prevent the technology from being abused for reproductive-cloning purposes."
Wh
A. make DNAs that are very small and have immune systems.
B. make DNAs that are as strong as antibiotics and vaccines.
C. make DNAs that are identical with those in the patients’ cells.
D. make DNAs that are consistent with the ACT research results.