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1.
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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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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Three hypotheses for cognitive deficits among psychopaths were tested: executive dysfunction, left hemisphere activation, and an interaction between the two. Twenty-one psychopathic and 23 nonpsychopathic criminal offenders identified with the Hare Psychopathy Checklist-Revised participated in verbal and visual-spatial tasks during which the level of executive processing demands was manipulated. Consistent with prior research, psychopathic offenders made more errors than controls, but only during the verbal task and only on trials with high executive demand. Within those trials, most errors occurred when set-maintenance demands were the highest. No response latency differences between groups were found.  相似文献   
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Three patients with lymphoid interstitial pneumonia (two HIV 1+ patients with chronic lymphadenopathic syndromes and one with a not-characterized autoimmune disease) have been studied with high-resolution computed tomography (HR-CT). This technique reveals septal lines, small reticulonodular opacities, polyhedral micronodular opacities, "ground-glass" opacities and a dense, subpleural, curved broken line in one patient. The lesions dominate in the bases of the lungs. They are not characteristic for lymphoid interstitial pneumonia. If a patient present with a chronic lymphadenopathic syndrome, the diagnosis of an opportunistic infection should not be automatically made, since the syndrome can be caused by lymphoid interstitial pneumonia.  相似文献   
10.
将昆明小鼠随机分为低(0.025)、中(0.05)、高(0.1)剂量组及生理盐水对照组,以2号海洛因经腹腔注射染毒,20天后,取睾丸组织制成石蜡切片.HE染色,光镜下观察生精小管上皮细胞的形态变化,并应用图像分析系统对初级精母细胞的形态参数进行了分析;结果表明,(1)光镜观察 对照组及低剂量组小鼠睾丸组织未见明显的变化;中剂量组小鼠睾丸曲细精管上皮有不同程度的组织改变;高剂量组小鼠生精管壁细胞明显地出现上皮层次减少,精子细胞和精子减少,并发现曲细精管内有脱落的生精细胞;(2)形态定量分析显示 低剂量组及中剂量组各形态参数(中剂量组圆形度除外)较对照组无显著差异;高剂量组初级精母细胞核面积、核灰度与对照组相比无显著差异,细胞面积、细胞周长及浆面积较对照组明显增大(P<0.05).而核浆比例、圆形度较对照组有减小(P<0.05).结果提示 海洛因可明显改变小鼠生殖细胞的形态结构.  相似文献   
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