Section, [act July 1, 1944, ch. 373, title III, § 312], formerly § 306, as added [Aug. 2, 1956, ch. 871], title I, § 101, [70 Stat. 923]; amended July 23, 1959, [Pub. L. 86–105, § 1], [73 Stat. 239]; Sept 8, 1960, [Pub. L. 86–720, § 1(b)], [74 Stat. 820]; Aug. 27, 1964, [Pub. L. 88–497, § 2], [78 Stat. 613]; Aug. 16, 1968, [Pub. L. 90–490, title III, § 302(b)], [82 Stat. 789]; Mar. 12, 1970, [Pub. L. 91–208, § 3], [84 Stat. 52]; Oct. 30, 1970, [Pub. L. 91–515, title VI, § 601(b)(2)], [84 Stat. 1311]; June 18, 1973, [Pub. L. 93–45, title I, § 104(a)], [87 Stat. 91]; renumbered § 312 and amended July 23, 1974, [Pub. L. 93–353, title I, § 102(b)], [88 Stat. 362]; Oct. 12, 1976, [Pub. L. 94–484, title I, § 101(a)(1)], [90 Stat. 2244], related to graduate or specialized training for physicians, engineers, nurses, and other professional personnel.