U.S. Healthcare Technologies Competitiveness Act of 2006 - Amends the Internal Revenue Code to provide tax incentives for investment in biomedical research corporations and related entities, by: (1) exempting investors in biomedical research corporations from limitations on net operating losses acquired through stock sales and mergers involving such corporations; (2) permitting a complete offset against the alternative minimum tax for the net operating losses of biomedical research corporations; (3) making permanent and increasing the rates for the tax credit for increasing research activities; (4) allowing tax credits for countermeasures equity investments and research expenses, qualified medical innovation expenses, equity investments in incubational companies, and investment in qualified biotechnology zone bonds; (5) accelerating eligibility for the tax credit for orphan drug expenses; (6) allowing expensing of biotechnology science park property and medical research equipment; (7) allowing deferral of the tax on gain from the sale of stock in a biomedical research corporation; (8) increasing the tax deductibility of capital losses on the sale of stock in biomedical research corporations; and (9) modifying passive loss deduction rules and S corporation shareholder requirements for biomedical research corporations.