Indigo Carmine: Indolesulfonic acid used as a dye in renal function testing for the detection of nitrates and chlorates, and in the testing of milk.Carmine: Coloring matter from the insect Coccus cacti L. It is used in foods, pharmaceuticals, toiletries, etc., as a dye, and also has use as a microscopic stain and biological marker.Organ Culture Techniques: A technique for maintenance or growth of animal organs in vitro. It refers to three-dimensional cultures of undisaggregated tissue retaining some or all of the histological features of the tissue in vivo. (Freshney, Culture of Animal Cells, 3d ed, p1)Isatin: An indole-dione that is obtained by oxidation of indigo blue. It is a MONOAMINE OXIDASE INHIBITOR and high levels have been found in urine of PARKINSONISM patients.Coloring Agents: Chemicals and substances that impart color including soluble dyes and insoluble pigments. They are used in INKS; PAINTS; and as INDICATORS AND REAGENTS.Vitellins: Major egg yolk proteins from egg-laying animals such as non-mammalian VERTEBRATES; ARTHROPODS; and others. They are high-density lipoglycoproteins derived from circulating precursors, VITELLOGENINS. Vitellins serve as nutrients for the growing non-mammalian embryos (EMBRYO, NONMAMMALIAN).Methylene Blue: A compound consisting of dark green crystals or crystalline powder, having a bronze-like luster. Solutions in water or alcohol have a deep blue color. Methylene blue is used as a bacteriologic stain and as an indicator. It inhibits GUANYLATE CYCLASE, and has been used to treat cyanide poisoning and to lower levels of METHEMOGLOBIN.Fallopian Tube Patency Tests: Methods for assessing the patency of the fallopian tubes.Oxygen Isotopes: Stable oxygen atoms that have the same atomic number as the element oxygen, but differ in atomic weight. O-17 and 18 are stable oxygen isotopes.