Shares of stem-cell therapy developers continued gaining ground Monday after President Barack Obama said he would overturn restrictions on federal funding for embryonic stem cell research.The reversal has been widely anticipated since the election, as Obama had pledged on the campaign trail to overturn the ban. The policy's main effect was on choking off funding to government agencies and academic research centers, as most stem cell companies relied on venture capital and other forms of funding to conduct research.Still, lifting the ban is symbolically positive for many companies, including Menlo Park, California-based Geron Corp., which has been working on embryonic stem-cell therapies for about a decade.Geron shares jumped 81 cents, or 20.1 percent, to $4.68 in midday trading. The stock has traded between $1.95 and $8.50 over the last 52 weeks. Geron is the first company to receive federal approval to begin human studies of an embryonic stem cell therapy.Embryonic stem cells are early-stage cells capable of becoming any of the more than 220 cell types in the human body. Their use in research and eventual treatments has been controversial because they are collected by cloning embryos in a laboratory, but the embryo is destroyed in the process.Other types of stem cells, such as adult stem cells, can be gathered from a person's skin, for example, and are less controversial, though many scientists have said that embryonic stem cells have a greater potential for medical therapies.Elsewhere, Rockville, Maryland-based Neuralstem is seeking FDA approval for human studies using adult stem cells. The stock rose 20 cents, or 23.3%, to $1.06 per share.Columbia, Maryland-based Osiris Therapeutics Inc., which focuses on adult stem cell-based therapies, gained 30 cents to reach $18.31. San Diego-based Cytori Therapeutics Inc. gained 47 cents, or 20.4%, to reach $2.78. The company is studying adult stem cells but also operates a tissue bank for the preservation of stem and regenerative cells.Shares of Palo Alto, California-based StemCells Inc., which also focuses on adult stem cells, surged 66 cents, or 47.8%, to $2.04.