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It is suggested that the numerous variants of diverticula occurring in the region of the major duodenal papilla should be grouped into four types. Type I--the major duodenal papilla (MDP) is on the floor of the diverticulum; type II--the MDP is in the region of the lower ++semi-circumference of the diverticular orifice while the longitudinal fold runs radially on the wall of the diverticulum; type III--the MDP is in the region of the orifice of the diverticulum while the longitudinal fold does not pass on its wall; type IV--two diverticula located above the MDP to both sides of the longitudinal fold. Endoscopic papillosphincterotomy is considered contraindicated in patients with type I diverticulum. When indicated, the intervention was carried out in patients with types III and IV diverticula. Endoscopic papillosphincterotomy can be conducted in patients with type II diverticulum measuring more than 2 cm. 相似文献
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T P Semenova E A Gromova N I Grischenko I V Nesterova A V Kulikov G N Smirnova T M Tretyak A G Bragin O S Vinogradova 《Neuroscience》1987,22(3):993-1002
Exploratory activity in the open field and noradrenaline concentration in the neocortex and brain stem were investigated in intact rats (n = 10) and in the following groups of rats with early postnatal neurotoxic (6-hydroxydopamine) lesion of the catecholaminergic system: (i) rats with embryonal locus coeruleus grafts in the frontal neocortex (n = 5); (ii) rats with the same grafts in lateral ventricles (n = 4); (iii) a control group with intracortical hippocampal tissue grafts (n = 3); (iv) sham-operated rats (n = 3). Experiments were performed by four independent groups of investigators using a double-blind method. In sham-operated rats as well as in rats with hippocampal grafts, and with locus coeruleus grafts in the ventricles, both exploratory activity and noradrenaline content of the forebrain were significantly lowered. In the rats with intracortical locus coeruleus grafts the level of exploratory activity was much higher (almost as in intact controls). This improvement of exploratory behaviour correlated highly with increased noradrenaline concentration in the forebrain. In all animals with locus coeruleus in lateral ventricles a significant increase in noradrenaline level of the brain stem was present, but no change of exploratory behaviour was observed. The grafts with the 3-mm-thick slabs of the adjacent tissue were dissected from the brain and used for histological analysis. The presence of typical locus coeruleus cells was shown in neocortex of all animals which received the grafts of corresponding tissue. The data show the possibility of stable compensation of the forebrain noradrenaline level and exploratory behaviour by embryonic noradrenergic neurons grafted into the neocortex, but not into lateral ventricles. 相似文献
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A decrease in the amplitude of miniature and evoked end-plate potentials (MEPPs and EPPs) as well as changes in EPP facilitation and depression during frequency stimulation were observed in psychosine-treated m. cutaneous-pectoris of the frog. Electron-microscopic investigation demonstrated severe changes in synaptic Schwann cells embracing motor terminals and disturbances in the inner mesaxon structure of the myelinated parts of motor terminals. 相似文献
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