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.
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.
Cervical Intraepithelial Neoplasia
A malignancy arising in uterine cervical epithelium and confined thereto, representing a continuum of histological changes ranging from well-differentiated CIN 1 (formerly, mild dysplasia) to severe dysplasia/carcinoma in situ, CIN 3. The lesion arises at the squamocolumnar cell junction at the transformation zone of the endocervical canal, with a variable tendency to develop invasive epidermoid carcinoma, a tendency that is enhanced by concomitant human papillomaviral infection. (Segen, Dictionary of Modern Medicine, 1992)
Prostatic Intraepithelial Neoplasia
A premalignant change arising in the prostatic epithelium, regarded as the most important and most likely precursor of prostatic adenocarcinoma. The neoplasia takes the form of an intra-acinar or ductal proliferation of secretory cells with unequivocal nuclear anaplasia, which corresponds to nuclear grade 2 and 3 invasive prostate cancer.