<p>By Rob Waters and Molly Peterson – Jul 30, 2010 <br /> Geron Corp. said it was cleared by U.S. regulators to proceed with the first human test of an embryonic stem-cell therapy, aimed at patients with spinal-cord injuries. The shares rose 17 percent.</p> <p>The Food and Drug Administration lifted a clinical hold on the study imposed last August when the company revealed that mice used in experimental work had…</p>