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91.
S Evers  B Bauer  B Suhr  H Voss  A Frese  I W Husstedt 《Neurology》1999,53(2):357-363
BACKGROUND: Cognitive processing in migraine is characterized by a loss of habituation during the interval and increased latencies in an attack. No studies are available on event-related potentials (ERPs) in cluster headache or chronic paroxysmal hemicrania. OBJECTIVE: To determine the involvement of cognitive processing in cluster headache and chronic paroxysmal hemicrania as measured by ERPs. METHODS: Visually evoked ERPs were measured in 50 patients with episodic cluster headache, 11 patients with chronic cluster headache, and 12 patients with chronic paroxysmal hemicrania. Measurements were performed in the cluster period outside an attack with and without prophylactic medication and not in the cluster period. RESULTS: Latencies of the endogenous ERP components were significantly increased during the cluster period as compared with outside the cluster period and with healthy subjects. In chronic cluster headache, latencies of both endogenous and exogenous components were increased. Medication with prophylactic drugs normalized the ERP latencies in episodic cluster headache; in chronic cluster headache, ERP latencies were decreased without complete normalization. No changes of ERP latencies and amplitudes could be observed in chronic paroxysmal hemicrania. A loss of cognitive habituation as it is known in migraine could not be observed in either cluster headache or chronic paroxysmal hemicrania. CONCLUSIONS: Our data suggest that central structures generating ERPs are involved in the pathophysiology of cluster headache during the cluster period but not outside the cluster period. This is in concordance with recent neuroimaging findings on the central role of the hypothalamus and the right frontal cortex in cluster headache and supports the hypothesis of a central origin of cluster headache. Furthermore, the data suggest that cluster headache and chronic paroxysmal hemicrania are distinct entities.  相似文献   
92.
Nineteen patients, who had undergone liver transplantation for familial amyloidotic polyneuropathy, had answered a quality of life questionnaire including 61 questions on somatic and mental symptoms, social aspects of life, confidence and satisfaction before, one year, and two years after transplantation. We found that patient satisfaction was generally good two years or more after the transplantation. Most of the patients were very or quite satisfied with the result. All of them had the drive to go on and felt hopeful about the future. However, on the second follow-up, 37% of the patients noted that they felt more insecure in their everyday life and there was a significant difference between the two assessments. The diarrhea score became worse between one and two years after the transplantation and was closely related to the duration of the gastrointestinal symptoms and to the duration of the disease before transplantation. The mental symptoms also increased significantly between the evaluations and this related to the severity of the somatic symptoms. Our conclusion is that liver transplantation should be performed before advanced somatic symptoms start to develop in order to improve the patients' chances of a good quality of life following liver transplantation.  相似文献   
93.
M el-Salhy  O Suhr  R Stenling  E Wilander    L Grimelius 《Gut》1994,35(10):1413-1418
Duodenal endocrine cells in 11 patients with familial amyloid associated polyneuropathy (FAP) were compared with those in 12 healthy volunteers by means of immunohistochemistry and morphometry. The total endocrine cell content, determined by the argyrophilic reaction and chromogranin A immunoreactivity, was significantly reduced in FAP patients compared with controls. There was a significant reduction in the serotonin, cholecystokinin/gastrin, and secretin immunoreactive cell content. A decreased cell content was also noted for somatostatin and gastric inhibitory polypeptide immunoreactive cells but this was not statistically significant. Amyloid deposits were noted in seven of the 11 biopsy specimens from FAP patients, but otherwise the duodenum was histologically normal in both groups. The reduction in endocrine cell content was not correlated with the degree of amyloid deposit in the duodenum. These findings indicate that patients with FAP have reduced intestinal endocrine cells. This does not seem to be related to amyloid deposits in the mucosa or to villous or crypt abnormalities. The observed changes in endocrine cells may contribute to the development of intestinal motility dysfunction and maldigestion in these patients.  相似文献   
94.
The sitting position for operations in the posterior fossa remains controversial in both adults and children, primarily because of the risk of air embolism. The reports on the incidence of this complication are varied. We retrospectively reviewed the data on 704 patients (age range 1–82 years) operated on in a lounging position for varied posterior fossa pathology from January 1984 up to December 1989. As diagnostic monitoring, we uniformly employed a Doppler ultrasound device, an atrial catheter, and capnometry. In 37 adults (5.5%) and 9 children (9/34) air embolism was diagnosed, without either morbidity or mortality. A lounging position, together with adequate infusion therapy and ventilation with PEEP, considerably reduces the risk of air embolism.  相似文献   
95.
96.
The influence of the white rot fungus Pleurotus ostreatus on the degradation of selected poly- and heterocyclic aromatic hydrocarbons (referred to as polycyclic aromatic hydrocarbons [PAHs]) in soil was investigated under field conditions representing the Northern temperate zone. Pleurotus ostreatus was added to two contaminated soils in the form of homogenized refuse from the commercial production of fungus. The soils were collected from a former shipyard (the B&W soil) and underneath a former coal tar storage at an old asphalt factory in Denmark (the Ringe soil). Treatments (control, soil mixed with autoclaved sawdust medium, and soil mixed with P. ostreatus refuse) were set up in triplicate in concrete cylinders (height, 50 cm; diameter, 60 cm). The activity of P. ostreatus was measured as laccase activity and phenanthrene (PHE)- and pyrene (PYR)-degrading bacteria were enumerated. Twenty-one different PAHs were quantified. After nine weeks the concentrations of the 3-, 4-, 5-, and 6-ring PAHs in the Ringe soil were reduced by 78, 41, and 4%, respectively. These reductions corresponded with high initial laccase activity, a decrease in pH caused by the fungus, and an increase in the number of PHE- and PYR-degrading bacteria. No significant PAH degradation was observed in the B&W soil. Reasons for the difference in performance of P. ostreatus in the two soils are discussed in terms of soil histories and bioavailability. The use of P. ostreatus refuse holds promising potential for bioremediation purposes.  相似文献   
97.
Eighty-one patients with diarrhoea due to suspected bacterial contamination of the small intestine were investigated with the bile acid breath test (BABT) and 75Se-labelled homocholic-tauro acid (SeHCAT). The impact of bile acid malabsorption due to dysfunction of the terminal ileum on BABT was evaluated. The group of patients with abnormal BABT, notably the 6-h accumulated value, showed a high frequency of reduced SeHCAT values (p less than 0.01), indicating that a reliable test for bile acid malabsorption is indispensable for interpreting the BABT in the investigation of small-intestinal bacterial overgrowth. The results of the 14C-D-xylose breath test were compared with the outcome of the combined SeHCAT-BABT in 44 patients. In contrast to previous findings no correlation between the two breath tests was found. On the contrary, a significant negative correlation was encountered (p less than 0.01) for patients in whom either breath test was abnormal. Scanning electron microscopy for demonstration of adherent microorganisms was included in the investigations. No correlations were found with the outcomes of the different breath tests. The effect of antibiotic treatment was evaluated with regard to symptoms and breath tests. The results of the investigation indicate that different tests are needed for the diagnosis of bacterial overgrowth of the small intestine, because of the different metabolic characteristics of the contaminating bacteria.  相似文献   
98.
Since oxidative stress has been implicated in amyloid diseases, a study of scavenger treatment of hereditary transthyretin amyloidosis was undertaken on 23 familial amyloidotic polyneuropathy (FAP) patients. Nine patients had undergone a liver transplantation for the disease. Twenty patients completed the 6-month study period of scavenger treatment (vitamin C, 1 g, three times daily, vitamin E, 0.1 g, three times daily and acetylcysteine, 0.2 g three times daily). They were evaluated clinically and by immunohistochemical measurement of hydroxynonenal (HNE), a product of lipid peroxidation, in biopsy specimens. For non-transplanted patients, no improvement was found for HNE in relation to the amyloid content in biopsy specimens, whereas a tendency to a decreased amount was noted for transplanted patients. Clinically, no differences were found for non-transplanted patients, but an increased nutritional status, measured by a modified body mass index (mBMI) was noted for transplanted patients. In summary, scavenger treatment with the drugs and doses used in the present study appears to be unable to decrease lipid peroxidation in amyloid-rich tissue in non-transplanted FAP patients. For transplanted patients, lipid peroxidation tended to decrease, and the nutritional status measured by mBMI improved, even though the findings may be explained by liver transplantation alone, scavenger treatment may facilitate recovery after transplantation.  相似文献   
99.
Factor analytic studies have long supported the division of schizophrenic symptoms into three relatively orthogonal factors: positive symptoms, negative symptoms, and disorders of relatedness/disorganization. Similarly, factor analyses of schizotypy often yield three factors: positive symptoms, negative symptoms, and social anxiety or disorganization. Recent cluster analyses, however, suggest that not all patients can be simply categorized according to these factors. Cluster analyses of schizotypal symptoms tend to result in clusters of individuals who are low in all factors, high in more than one factor, or high predominantly in one factor. The present study sought to compare factor and cluster models of schizotypal symptoms, as measured by the SPQ, PAS, and MIS, in unselected individuals and highly schizotypal individuals. Consistent with prior research, factor analysis of a large unselected undergraduate sample yielded three factors: "positive", "negative", and "disorganized." Factor analysis of schizotypal undergraduates produced the same three factors, plus a fourth designated "paranoid thinking." In contrast, cluster analysis of the unselected sample yielded four clusters ("low schizotypy", "average schizotypy", and "high schizotypy", plus "positive/disorganized"). Cluster analysis of the schizotypal subsample produced four clusters: "low schizotypy", "positive", "negative" and "high schizotypy."  相似文献   
100.
The present study explored the explanatory power of Mittenberg's "expectation as etiology" theory for the persistence of postconcussion syndrome (PCS) complaints. One hundred forty-one participants completed a PCS symptom checklist under 2 conditions. Normal controls, healthy athletes and depressed individuals reported current symptoms and symptoms expected following a hypothetical mild head injury. Head-injured athletes, chronic headache sufferers, and a 2nd sample of normal controls reported current symptoms and retrospective symptoms (prior to their injury/illness or from some point in the past). Depressed individuals reported more current symptoms than normal controls and healthy athletes, demonstrating that "PCS" symptoms are not specific to PCS. All groups expected more symptoms following mild head injury than currently experienced, supporting the idea that individuals expect negative consequences following head injury. However, healthy athletes expected fewer symptoms than normals or depressed individuals, possibly due to preexisting expectations for speedy recovery. Both head-injured athletes and headache sufferers reported more current symptoms than the past, but not at a rate lower than baseline of normal controls. Results suggest that the "expectation as etiology" hypothesis may be too specific, and that, following any negative event, people may attribute all symptoms to that negative event (the "good old days" hypothesis).  相似文献   
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