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| Could you imagine having a cut heal
almost overnight(一夜之情) Scientists at the University of California in San Francisco have isolated(分离) a sub- stance in rabbits that can heal wounds in half the time! The substance, called angiogenesis(血管生成因子) factor, stimulates the growth of blood vessels after injury. Blood vessels are essential to recovery because they carry oxygen and nutrients to cells that both kill germs and repair tissues. All mammals(哺乳动物), from rats to whales to human beings, carry this substance in their bodies. Further research may permit scientists to create artificial angiogenesis factor in the laboratory. Angiogenesis factor, scientists say, would be of value to patients undergoing organ transplants and skin grafts because rapid healing would reduce the time during which infection could strike. The substance could also help "slow healer," such as diabetics, the aged, and the very ill. Cancer researchers are also interested in angiogenesis factor because tumors, like other tissues, depend on blood vessels for growth. Scientists believe that angiogenesis factor may cause this same blood vessel growth in tumors. If antibodies (special body substances that fight disease) against the factor could be found, cancerous tumors could be starved and destroyed. |