What is the sum of the [3 H]CFT with an N ÷ D less than 393.8 and a [3H] paroxetine of 1045 (45)?
CREATE TABLE "pharmacotherapy_for_cocaine_abuse" (
  "3_h_cft" real,
  "3_h_nisoxetine" text,
  "3_h_paroxetine" text,
  "n_d" real,
  "s_d" real
);
SELECT SUM("3_h_cft") FROM "pharmacotherapy_for_cocaine_abuse" WHERE "n_d"<393.8 AND "3_h_paroxetine"='1045 (45)';