Laser lithotripsy. Laser lithotripsy is a surgical procedure to remove stones from urinary tract, i.e., kidney, ureter, bladder, or urethra.
HIV-1 is surprisingly old, and it probably debuted in humans at least three separate times -- one for each subtype, M, N, and O. Scientists' best guess is that the precursor of the most common M virus jumped from the Cameroon chimps to humans sometime before 1931.art One: Chapter Four Scientific Breakthroughs. HIV-1, which is responsible for the vast majority of AIDS cases worldwide, is divided into three groups -- the major group M, and the much rarer outlier group O and new group N -- that have diverged over years of mutation and evolution.
HIV-2 is less transmittable and is largely confined to West Africa, along with its closest relative, a virus of the sooty mangabey (Cercocebus atys atys), an Old World monkey inhabiting southern Senegal, Guinea-Bissau, Guinea, Sierra Leone, Liberia, and western Ivory Coast.he authors proposed that HIV-1 originated in the area of French Equatorial Africa in the early 20th century (when the colonial abuses and forced labor were at their peak). Later researches proved these predictions mostly correct: HIV-1 groups M and O started to spread in humans in late 19thâearly 20th century.