Electron microscopic and immunohistochemical studies of oral malignant melanoma

Abstract

Abstract.A rare variety of malignant melanoma in the maxilla was studied by electron microscopic observation and an immunohistochemical investigation of the transferrin receptor (TfR). A number of low-stage melanosomes were seen, and the TfR was found in both the cell membrane and the cytoplasm.

Deposition of osmium thin films using pyrazolate complexes as CVD source reagents

“…As indicated in Fig. 2, the complex 1 consists of three Os atoms that form an isosceles triangle with distances Os(1)-Os(2) ~2.9135(4), Os(1)-Os(3) ~2.8685(4) and Os(2)-Os(3) ~2.8642(4) A ˚, of which the longer Os-Os edge is bridged by the pyrazolate ligand and a hydride ligand at the opposite position, with distances Os(1)-H(1) ~1.79 (6) and Os(2)-H(1) ~1.80(6) A ˚. Basically, this structure can be considered to derive from the parent complex Os 3 (CO) 12 by replacement of two axial CO groups on adjacent Os atoms by the bridging pyrazolate and hydride ligands.…”

“…Since the first successful deposition of Os metal by hydrogen reduction of OsCl 4 vapor, 4 only a few reports have been focused on its continued improvement. In recent years, work on the chemical vapor deposition of osmium has started to utilize the commercially available osmocene (C 5 H 5 ) 2 Os, 5 osmium tetraoxide OsO 4 , 6 or even the metal carbonyl complexes such as Os(CO) 5 , 7 Os 3 (CO) 12 , 8 and Os(CO) 4 (hfb), 9,10 where hfb ~hexafluorobut-2-yne, to produce pure osmium metal or the respective metal oxide material OsO 2 . It has been reported that thin films with reasonable purity were obtained in most of the previous studies; however, the usage of these source reagents has encountered difficulties such as the greater toxicity of OsO 4 , poor thermal stability of Os(CO) 5 , and lower gas phase transportation capability for the osmocene complex (C 5 H 5 ) 2 Os and polynuclear metal complex Os 3 (CO) 12 .…”