61.   Researchers suspect the water in the shuttle aquarium was too warm.

62.   Scientists had previously found these cells in HIV-infected people without AIDS, and some researchers suspect the cells may help keep those people healthy.

63.   Researchers earlier suspected that human chorionic gonadotropin, or HCG, a hormone produced during pregnancy, was responsible for protecting against HIV and other viruses.

64.   Researchers have long suspected, even before HIV was identified, that drugs like cocaine and heroin can suppress the immune system and accelerate the spread of the virus.

65.   Researchers suspected some special cells in the bone marrow somehow were prompted to start making new cells for the distressed organ.

66.   Researchers suspected that repeated blows to the head could have been the cause.

67.   Researchers have long suspected that some heart-transplant failures are caused by viruses.

68.   The comparative number of males has been declining in several industrialized countries over the past few decades and researchers suspect toxic substances may be partly to blame.

69.   The exact cause of the glandular problem has not been established, but researchers suspect a link with PCBs and perhaps other chemicals, she said.

70.   The researchers suspect these babies may be prone to elevated blood pressure as they age, which would increase their risk of heart trouble.