title: Results obtained in peforating keratoplasty with preserved corneas, using liquid nitrogen.
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D016039:Corneal Transplantation; D005260:Female; D005615:Freezing; D006801:Humans; D008297:Male; D008722:Methods; D008875:Middle Aged; D009584:Nitrogen; D011183:Postoperative Complications; D014021:Tissue Preservation; D014184:Transplantation, Homologous
chemical_list: D009584:Nitrogen