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21.
Six of 12 children with Down syndrome (DS) tested by means of long-term tape-recordings of oxygen saturation, breathing movements and expired CO2 were found to have previously undetected and severe upper airway obstruction during sleep. In five cases the obstruction occurred in the pharynx and in the sixth it was due to bilateral choanal stenosis. When compared with age-matched controls, overnight tape-recordings showed episodes of abnormal arterial hypoxaemia and an abnormally elevated end-tidal CO2. Episodes of obstruction were most marked during sleep associated with a non-regular breathing pattern. Abnormal episodes of hypoxaemia were associated with continued breathing movements. Sometimes there was no airflow (complete obstruction); at other times airflow continued normally or was reduced in amplitude (partial obstruction). During episodes of partial or complete airway obstruction the inspiratory waveform showed a characteristic shape. These results show sleep-related upper airway obstruction to be an often undetected complication of DS and all necessary measures should be taken to overcome the obstruction when it reaches the stage of producing abnormal hypoxaemia. Choanal dilatation and tracheostomy were successful in treating two of the children. Tonsillectomy and adenoidectomy were successful for one child, but only of marginal benefit for two others.  相似文献   
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Self-report questionnaires completed by young adults with Type I diabetes were examined to determine if individuals differing in recent metabolic control (Poor, Moderate or Very Good) or disease duration (Long, Short) also vary in either occurrence or type of life events during the past year or occurrence of recent emotional distress. Subjects in Poor control reported more positive and neutral life events during the past year, suggesting even those life changes individuals view benignly may be associated with metabolic control difficulties. Individuals in Poor control also reported more recent symptoms of depression, anxiety and hostility than did individuals in Moderate or Very Good control--symptomatology which may further impair their ability to adhere to a complex self-care regimen. Individuals with Long disease duration reported more positive and negative recent life experiences than did subjects with Short disease duration, but did not evidence concomitant disruptions in metabolic control. The role experience with a chronic disease may play in this finding was unclear, however. Although more research is required to clarify the exact relation of psychosocial variables and diabetic control, these findings suggest that clinically relevant subgroup parameters, subjects' perceptions of life change, and demographic variables may be important factors to assess.  相似文献   
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The pathophysiological changes in neural activity that characterize multiple system atrophy (MSA) are largely unknown. We recorded the activity of pallidal neurons in 3 patients with clinical and radiological features of MSA who underwent unilateral microelectrode-guided pallidotomy for disabling parkinsonism. Findings in these patients were compared with 4 control patients with a clinical diagnosis of Parkinson's disease (PD). The position, firing rates, and firing patterns of single neurons in the pallidal complex were analyzed in both MSA and PD patients. The mean spontaneous firing rate of neurons in the internal segment of the globus pallidus internus (GPii) was significantly lower in MSA than in PD patients. There were no significant differences between MSA and PD patients, however, in firing rates of neurons in the external globus pallidus (GPe) or in the external segment of GPi (GPie). In addition, no significant differences in firing pattern were found between MSA and PD patients. In conclusion, this study has shown that firing rates of neurons in GPii but not in GPie and GPe are different in MSA patients compared with that in PD patients, a finding that may reflect the poor clinical results of pallidotomy reported in patients with MSA.  相似文献   
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The Lambert-Eaton myasthenic syndrome (LEMS) is an autoimmune disease that can be transmitted from human to mouse with immunoglobulin G (IgG). Electrophysiological studies indicate that LEMS IgG acts on presynaptic voltage-sensitive calcium channels, probably reducing their number, and freeze-fracture electron microscopy demonstrates that LEMS IgG has an effect on the presynaptic active zone particles, which represent putative voltage-sensitive calcium channels. The active zone particles, normally arranged in double parallel rows, move closer together, form clusters, and are reduced in number. The morphological data suggest modulation of the active zone particles crosslinked by LEMS IgG. If this were the case, then only divalent LEMS IgG and F(ab')2 should alter the deployment of active zone particles and monovalent Fab should be without effect. To test this hypothesis, mouse diaphragms were exposed to control and LEMS IgG and IgG fragments in organ culture for 24 hours and then studied by quantitative freeze-fracture electron microscopy. Divalent LEMS IgG and F(ab')2 aggregated and depleted the active zone particles, whereas monovalent Fab had no effect. The findings reconfirm that the active zone particles are targets of LEMS IgG and are direct evidence for modulation of the particles by LEMS IgG. The findings are in harmony with parallel electrophysiological studies of the effects of LEMS IgG fragments on transmitter release in the same diaphragm muscles (Lang et al, J Physiol 1987;390:173P).  相似文献   
27.
Zentrale Gallengangskarzinome   总被引:1,自引:0,他引:1  
Surgical resection provides the only chance of cure for patients suffering from hilar cholangiocarcinoma. Due to the central anatomic localization within the liver hilum, established guidelines of oncologic surgery are difficult to apply. Resection of the hilar bifurcation alone or in combination with limited hepatic resection can be performed with low morbidity and low mortality but shows a high rate of local tumor recurrence. Usually, extended resection is required to achieve adequate safety margins. Right trisectionectomy complies best with the basic rules of oncologic surgery while allowing the maximum safety margin. The 5-year survival rates reported after right trisectionectomy range between 20% and 40% and reach 59% in selected patients. The increasing experience with living donor transplantation and recent advances in neoadjuvant tumor therapy may lead to renewed discussion of liver transplantation in hilar cholangiocarcinoma.  相似文献   
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The following article presents two new cases of a lipofibroma of the median nerve. This formation is a very rare benign tumor of peripheral nerve tissue. Up to now 30 cases have been reported in the literature and are reviewed in this article and are compared with the two cases reported. Besides the operative treatment, which made the neuropathological diagnosis possible, preoperative diagnosis has been extended by MNT-scans of the involved parts of the nerve. The noninfiltrating character of the tumor could be well recognized on these scans. The signal quality and the anatomical proximity to the median nerve made the diagnosis of a lipofibroma likely. By the postoperative histological reviews the diagnosis was confirmed in classic manner. The immunological marking of the S-100 protein showed a remarkable reduction of this protein in these peripheral nerve tumors. The two cases reported by us recapitulate the clinical history typically and describe symptoms and our treatment for the lipofibroma of the median nerve.  相似文献   
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