Clinical Research Enhancement Act of 1997 - Amends the Public Health Service Act to require the Director of the National Institutes of Health (NIH) to: (1) support and expand the NIH's involvement in clinical research; (2) support and expand the resources available for the clinical research community; and (3) establish peer review mechanisms.

(Sec. 4) Mandates grants to: (1) establish general clinical research centers to provide the infrastructure for clinical research, including clinical research training and career enhancement; (2) support individual careers in clinical research at general clinical research centers or other institutions (to be known as clinical research career enhancement awards); (3) support individual clinical research projects at general clinical research centers or other institutions; and (4) support individuals pursuing master's or doctoral degrees in clinical investigation (to be known as graduate training in clinical investigation awards). Authorizes appropriations.

(Sec. 5) Increases the limit on the aggregate number of scholarship (regarding professions needed by the NIH) and loan repayment (regarding clinical researchers from disadvantaged backgrounds) contracts under specified provisions.

Modifies the loan repayment program to: (1) remove current references to disadvantaged backgrounds; and (2) require a period of service in a general clinical research center, in clinical NIH research, or as a physician receiving a clinical research career enhancement award or a graduate training in clinical investigation award (currently, a period of service as an NIH employee). Requires that at least 50 percent of the loan repayment contracts involve individuals from disadvantaged backgrounds. Authorizes appropriations to carry out the loan repayment provisions.