Bone and joint lesions in decompression sickness.

1 Of 450 divers, 268 (59.5%) has aseptic necrosis of bone; 81 had articular lesions. 2 In proportion to duration of diving experience and maximum depth of diving, incidence of bone necrosis increases. 3 The radiological lesions have been classified by modified Ohta-Matsunaga criteria. 4 Yearly progress of bone changes were mentioned. 5 Pathological appearances of aseptic necrosis of bone in divers are compared with different types of bone necrosis. 6 Experimental studies for aseptic necrosis were mentioned. 7 Etiology of bone necrosis is not yet clear, but some etiological factors were discussed. It was suggested that fat embolism was an important factor, because fat embolisms were seen in our pathological findings of the divers and compressed-air workers. 8 Periodic radiological examination of the bones of divers and compressed-air workers should be carried out. It is important to research the new modified decompression table to prevent bone necrosis. 9 Surgical treatment of bone necrosis was mentioned.

The Microwave Spectrum of n-Butyraldehyde Oxime.

The microwave spectrum of n-butyraldehyde oxime was observed in the frequency region 26.5-40 GHz. Four rotational conformers were found to exist in the gas phase; among these, two conformers belonged to the (E)-geometrical isomer and the other two to the (Z)-geometrical isomer. The microwave spectrum attributed to one of these two rotational conformers of (E)-butyraldehyde oxime was analyzed, and its rotational constants for the ground vibrational state were determined: A = 15883(379), B = 1269.97(1), C = 1251.60(1) MHz. The conformational structure of the molecule is discussed, referring to the rotational constants obtained and the ab initio molecular orbital calculation. Copyright 1998 Academic Press.