Ejaculatory Ducts: Paired ducts in the human male through which semen is ejaculated into the urethra.Hemospermia: Blood in the SEMEN, usually due to INFLAMMATION of the PROSTATE, the SEMINAL VESICLES, or both.Genital Diseases, Male: Pathological processes involving the male reproductive tract (GENITALIA, MALE).Seminal Vesicles: A saclike, glandular diverticulum on each ductus deferens in male vertebrates. It is united with the excretory duct and serves for temporary storage of semen. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Tetralones: A group of TETRAHYDRONAPHTHALENES containing a keto oxygen.Holmium: Holmium. An element of the rare earth family of metals. It has the atomic symbol Ho, atomic number 67, and atomic weight 164.93.Autonomic Agents: Agents affecting the function of, or mimicking the actions of, the autonomic nervous system and thereby having an effect on such processes as respiration, circulation, digestion, body temperature regulation, certain endocrine gland secretions, etc.Ejaculation: The emission of SEMEN to the exterior, resulting from the contraction of muscles surrounding the male internal urogenital ducts.Genitalia, Male: The male reproductive organs. They are divided into the external organs (PENIS; SCROTUM;and URETHRA) and the internal organs (TESTIS; EPIDIDYMIS; VAS DEFERENS; SEMINAL VESICLES; EJACULATORY DUCTS; PROSTATE; and BULBOURETHRAL GLANDS).Infertility, Male: The inability of the male to effect FERTILIZATION of an OVUM after a specified period of unprotected intercourse. Male sterility is permanent infertility.Premature Ejaculation: The emission of SEMEN and seminal fluid during the act of preparation for sexual intercourse, i.e. before there is penetration, or shortly after penetration.Constriction, Pathologic: The condition of an anatomical structure's being constricted beyond normal dimensions.Sexual Dysfunction, Physiological: Physiological disturbances in normal sexual performance in either the male or the female.