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The United States seems to be losing patience with the only existing agreement on strategic arms. But the US's tetchy demeanour may prove to be an embarrassment.
Molecular biology is providing novel means of testing for genetic disease, with the result that researchers are having to spend their time on repetitive testing. Now is the time to make better plans.
Heparin-affinity chromatography allows the isolation and chemical definition of a family of hormone-like polypeptide growth factors that support several important cell types in defined culture conditions.