Word: drs
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Dates: during 1950-1959
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...Virus Laboratory of the University of California, two researchers announced this week that they have taken an infectious virus apart and reduced it to a mixture of utterly dead chemicals, then put it together and made it infectious again. Drs. H. Fraenkel-Conrat and Robley C. Williams do not want it said that they have "created life"; a simple virus is alive in a special sense only. But they do believe that they have come closer to one of science's major aims-knowing the nature of life. Says Dr. Williams: "We have no doubt that eventually we will...
Degraded Virus. The two researchers worked with the simple and well-known virus that causes mosaic disease in tobacco plants and is called TMV for short. Its particles are rod-shaped, and are known to consist of central cores of nucleic acid with protein molecules strung around them. Drs. Fraenkel-Conrat and Williams prepared pure solutions of the submicroscopic rods, mixed them with dilute alkaline chemicals and held them close to the freezing point for two to three days. This treatment "degraded" some of the virus, separating the rods into nucleic acid and protein molecules. Undegraded rods were taken...
...Drs. Fraenkel-Conrat and Williams then mixed the two parts of the virus together, made the solution slightly acid and held it just above freezing point for 24 hours. At the end of this period, the protein molecules had rearranged themselves on the nucleic acid cores. When tested on tobacco plants, the virus proved infectious. It grew and multiplied in the green leaves, producing the characteristic spots of tobacco mosaic disease...
...When a blood clot in a coronary artery causes a heart attack, one result may be an aneurysm-something like a big blister-bulging from the heart muscle. Drs. William Likoff and Charles P. Bailey of Philadelphia's Hahnemann Hospital report what is believed to be the first successful operation to remove one. A man of 56, formerly bedridden, has been, able to climb stairs without distress since the operation 15 months...
...Ohio State University, Drs. Henry M. Moser, John J. Dreher and Herbert Oyer, backed by the Air Force, are trying to develop a special ear microphone. They have found that when a speaker's mouth is covered by a sound-absorbing baffle, his speech can be heard, weakly but distinctly, through a stethoscope in one of his ears. Picked up with a microphone, ear speech can be amplified until it is as loud as desired. It has a rather "bright" sound, but is not very different from mouth speech...