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Natural Medicines
Since earliest days, humans have used some kinds of medicines. We know this because hu-mans have survived. Ancient treatments for injury and disease were successful enough to keep hu-mans from dying out completely.
They were successful long before the time of modem medicine. Before the time of doctorswith white coats and shiny （发亮的）nstruments. Before the time of big hospitals with strangeand wonderful equipment.
Many parts of the world still do not have university-educated doctors. Nor do they have ex-pensive hospitals. Yet injuries are treated. And diseases are often cured. How? By ancient meth-ods. By medicines that might seem mysterious, even magical （有魔力的）Traditional medicinesare neither mysterious nor magical, however.
Through the centuries, tribal (部落的) medicine men experimented with plants. They foundmany useful chemicals in the plants. And scientists believe many of these traditional medicinesmay provide the cure for some of today&39;s most serious diseases.
Experts say almost 80% of the people in the world use plants for health care. These naturalmedicines are used not just because people have no other form. of treatment. They are used be-cause people trust them. In developed areas, few people think about the source of the medicinesthey buy in a store. Yet many widely-used medicines are from ancient sources, especially plants.Some experts say more than 25 % of modem medicines come, in one way or another, from nature.
Scientists have long known that nature is really a chemical factory. All living things containchemicals that help them survive. So scientists&39; interest in traditional medicine is not new. But ithas become an urgent concern. This is because the earth&39;s supply of natural medicines may bedropping rapidly.
The passage indicates that ancient treatments for injury and disease were 查看材料