Takaaki Ito

A Case of Somatostatinoma of the Pancreas, Accompanied with Pancreas Divisum, that was Found at a Time of Acute Pancreatitis

Somatostatinomaは膵臓あるいは十二指腸に好発するまれな内分泌腫瘍である, 今回, 我々は膵癒合不全のため膵液の主排出路となっていた副膵管がsomatostatinomaにより閉塞し急性膵炎を発症した症例を経験した. 症例は65歳の男性で, 上腹部痛を主訴に来院し, 急性膵炎と診断された. 膵炎軽快後の内視鏡的逆行性膵管造影検査で背側膵管と腹側膵管が分枝のみで交通する膵管非癒合の所見を認め, また, 副膵管の途絶とその上流側膵管の拡張を認めた. 内視鏡所見では十二指腸下行脚副乳頭に一致する部位に潰瘍性腫瘍病変を認めた. 腫瘍により副膵管が閉塞し, その結果急性膵炎が発症したと考えられた. 急性膵炎の軽快した後に膵頭部癌の診断で膵頭十二指腸切除術を施行した. 病理組織学的に膵内分泌腫瘍と診断され, 免疫組織学的にsomatostatinで濃染された. 膵somatostatinomaと診断された.

Numerical Prediction of NOx Reduction Amount by NOx Storage-Reduction Catalysts under Sulphur Poisoning Condition (Application of Catalyst Model Considering Diffusion into Wash-Coat)

The catalyst model which considers diffusion phenomena in the wash-coat layer has been developed and applied to NOx storage reduction (NSR) catalysts under sulphur poisoning condition. In this model, the effective reaction rate, which can be measured by experiments, is expressed as the harmonic mean of the diffusion rate from bulk gas phase to wash-coat surface in the channel, the diffusion rate in the wash-coat layer which has a large number of pores and reaction rate on the noble metal surface. Analysis of numerical results of NOx reduction phesomena of NSR catalysts by means of this model leads to following conclusions. Sulphur poisoning level doesnt affect NOx reduction reaction rate constants on the noble metal surface. The effective NOx reduction rate is dominated by the diffusion rate in the wash-coat layer at temperatures approximately over 600 K.