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Physics of the Future: How Science Will Shape Human Destiny and Our Daily Lives by the Year 2100

Physics of the Future: How Science Will Shape Human Destiny and Our Daily Lives by the Year 2100

Titel: Physics of the Future: How Science Will Shape Human Destiny and Our Daily Lives by the Year 2100 Kostenlos Bücher Online Lesen
Autoren: Michio Kaku
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Diego Zoo asked him to clone a banteng, an endangered species of wild ox, from the body of one that had died twenty-five years before. Lanza successfully extracted usable cells from the carcass, processed them, and sent them to a farm in Utah. There, the fertilized cell was implanted into a female cow. Ten months later he got news that his latest creation had just been born. On another day, he might be working on “tissue engineering,” which may eventually create a human body shop from which we can order new organs, grown from our own cells, to replace organs that are diseased or have worn out. Another day, he could be working on cloning human embryo cells. He was part of the historic team that cloned the world’s first human embryo for the purpose of generating embryonic stem cells.
    THREE STAGES OF MEDICINE
    Lanza is riding a tidal wave of discovery, created by unleashing the knowledge hidden within our DNA. Historically, medicine has gone through at least three major stages. In the first, which lasted for tens of thousands of years, medicine was dominated by superstition, witchcraft, and hearsay. With most babies dying at birth, the average life expectancy hovered around eighteen to twenty years. Some useful medicinal herbs and chemicals were discovered during this period, like aspirin, but for the most part there was no systematic way of finding new therapies. Unfortunately, any remedies that actually worked were closely guarded secrets. The “doctor” earned his income by pleasing wealthy patients and had a vested interest in keeping his potions and chants secret.
    During this period, one of the founders of the Mayo Clinic kept a private diary when he made the rounds of his patients. He candidly wrote in his diary that there were only two active ingredients in his black bag that actually worked: a hacksaw and morphine. The hacksaw was used to cut off diseased limbs, and the morphine was used to deaden the pain of the amputation. They worked every time. Everything else in his black bag was snake oil and a fake, he lamented sadly.
    The second stage of medicine began in the nineteenth century, with the coming of the germ theory and better sanitation. Life expectancy in the United States in 1900 rose to forty-nine years. When tens of thousands of soldiers were dying on the European battlefields of World War I, there was an urgent need for doctors to conduct real experiments, with reproducible results, which were then published in medical journals. The kings of Europe, horrified that their best and brightest were being slaughtered, demanded real results, not hocus-pocus. Doctors, instead of trying to please wealthy patrons, now fought for legitimacy and fame by publishing papers in peer-reviewed journals. This set the stage for advances in antibiotics and vaccines that increased life expectancy to seventy years and beyond.
    The third stage of medicine is molecular medicine. We are seeing the merger of physics and medicine, reducing medicine to atoms, molecules, and genes. This historic transformation began in the 1940s, when Austrian physicist Erwin Schrödinger, one of the founders of the quantum theory, wrote an influential book called
What Is Life?
He rejected the notion that there was some mysterious spirit, or life force, that animated living things. Instead, he speculated that all life was based on a code of some sort, and that this was encoded on a molecule. By finding that molecule, he conjectured, one could unravel the secret of life. Physicist Francis Crick, inspired by Schrödinger’s book, teamed up with geneticist James Watson to prove that DNA was this fabled molecule. In 1953, in one of the most important discoveries of all time, Watson and Crick unlocked the structure of DNA, a double helix. When unraveled, a single strand of DNA stretches about six feet long. On it is contained a sequence of 3 billion nucleic acids, called A,T,C,G (adenine, thymine, cytosine, and guanine), that carry the code. By reading the precise sequence of these nucleic acids placed along the DNA molecule, one could read the book of life.
    The rapid advances in molecular genetics finally led to the creation of the Human Genome Project, truly a milestone in the history of medicine. A massive, crash program to sequence all the genes of the human body, it cost about $3 billion and involved the work of hundreds of scientists collaborating around the world. When it was finally completed in 2003, it heralded a new era in

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