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61.
Approach-avoidance animal models are useful as initial screens for drugs affecting anxiety, but the components of anxiety assessed by these models remain poorly defined. Complex models of evaluation allow more complete inferences than those which are obtained when only one behavior is evaluated. Previous studies demonstrate that the tricyclic-antidepressant desipramine exerts a selective anticonflict effect on adult rats submitted to a protein deprivation schedule at perinatal age, in parameters of spontaneous behavior (elevated plus-maze) and conditioned intake (Geller Seifter). These deprived rats show alterations in noradrenergic neurotransmission that resembled the generalized activation of noradrenergic system displayed by patients suffering from panic attacks. The desipramine anticonflict activity was evaluated by a test of ethological conflict: the Open Field Drink Test, without discarding any behavior a priori under a multivaried approach. This approach has not been considered in previous studies with the open field and antipanic drugs. Considering the four variables selected by factorial analysis, desipramine (10 mg/kg/day) administered IP during just 7 days produced a significant diet x drug interaction which was consistent with previous studies. That interaction was independent of the effects of both treatments on weight or intake and was expressed, on deprived rats, as a decrease in all the behaviors, except for the time of drinking, with respect to the control rats, which displayed, in general, a decrease in all the behaviors except for the frequency of grooming.  相似文献   
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We report the first case of isolated biotin resistant 3-methylcrotonyl-CoA carboxylase (MCC) deficiency in Argentina. The diagnosis was established at 14 months of age by urinary organic-acid analysis and confirmed by enzyme assay in fibroblasts. The patient suffered from severe psychomotor retardation, hypotonia, areflexia, and failure to thrive, and died unexpectedly at 3 years 4 months of life. Brain MRI at 14 months showed signals of the white matter on cerebral T2-weighted, which were indicative of confluent and multiple foci of leukodystrophy, a pattern not previously described in this entity. In addition, high levels of oxypurines were detected in cerebrospinal fluid. This might be related to energetic consequences of the enzyme deficiency in the brain. This case extends the phenotype of isolated MCC deficiency in infancy and suggests this entity should be considered to be one of the possible causes of metabolic leukodystrophies.  相似文献   
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Liver changes in patients with hyperthyroidism   总被引:4,自引:0,他引:4  
We studied liver changes in the hepatic biopsies of five patients with hyperthyroidism. A characteristic histopathologic picture consisting of mild to moderate intrahepatocytic cholestasis, lobular inflammatory infiltrate with some eosinophils, and Kupffer cell hyperplasia was found in all cases. We discuss the specificity, clinicopathological correlations and the possible pathophysiology of these lesions.  相似文献   
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Immunosuppression can allow organisms that are not usually pathogenetic to cause disease; under such circumstances, Aspergillus species frequently form large masses of fungal elements. We describe the case of a 12-year-old girl with hematologic remission of leukemia. She had a left ventricular pedunculated mass that was detected by echocardiographic study; at surgery, the presence of Aspergillus terreus was confirmed.  相似文献   
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A 34-y-old man presented to Naivasha District Hospital (NDH) in Naivasha Town, Kenya, with near-complete below-knee amputation and hemorrhage after a hippopotamus attack. Residents from the University of Washington (UW), Departments of Surgery, Anesthesia, and Medicine, were rotating at NDH with the Clinical Education Partnership Initiative, a joint venture of UW and University of Nairobi. These providers met the patient in the operating theater. The leg was mangled with severely traumatized soft tissues and tibia–fibula fractures. The visiting UW Surgery resident (R3) and an NDH medical officer (second-year house officer) performed emergency below-knee completion amputation—the first time either had performed this operation. The three major vessel groups were identified and ligated. Sufficient gastrocnemius and soleus were preserved for future stump construction. The wound was washed out, packed with betadine-soaked gauze, and wrapped in an elasticized bandage. Broad-spectrum antibiotics were initiated. Unfortunately, the patient suffered infection and was revised above the knee. After a prolonged course, the patient recovered well and was discharged home. NDH house officers and UW trainees collaborated successfully in an emergency and conducted the postoperative care of a patient with a serious and challenging injury. Their experience highlights the importance of preparedness, command of surgical basics, humility, learning from mistakes, the expertise of others, a digitally connected surgical community, and the role of surgery in global health. These lessons will be increasingly pertinent as surgical training programs create opportunities for their residents to work in developing countries; many of these lessons are equally applicable to surgical practice in the developed world.  相似文献   
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