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81.
Rats with lesions of the medial prefrontal, posterior parietal,or posterior temporal cortex were tested in five spatial navigationtasks, which varied in egocentric or allocentric demands, avisual discrimination task, and two delayed nonmatching-to-sampletasks. Rats with prefrontal lesions were impaired at every spatialnavigation task, whereas rats with posterior parietal lesionshad selective spatial navigation impairments. Rats with prefrontallesions were also impaired at a visual delayed nonmatching-to-sampletask, as they were unable to learn the task, even with no delay.The results are consistent with the idea that the basic planof mammalian cortex includes prefrontal, posterior parietal,and posterior temporal regions, each of which have generallysimilar functions across mammalian taxa. There are, however,species-typical differences that reflect specific ecologicalpressures on the development of the different regions.  相似文献   
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Myocarditis is a major cause of end-stage heart failure and is responsible for up to 10% of cases of idiopathic dilated cardiomyopathy (IDC). Worldwide, approximately 45% of all heart transplants are performed for IDC and up to 8% for myocarditis. Early reports suggested that survival after transplantation for myocarditis was poor and patients had an increased risk of rejection. More recently, larger case series suggest that overall survival after transplantation for myocarditis is similar to survival after transplantation for other causes. However, certain disorders, including cardiac sarcoidosis and giant cell myocarditis (GCM), require heightened surveillance for post-transplantation disease recurrence. We present the case of a 42-year-old man with recurrence of GCM 8 years after transplantation and review the literature on the role of cardiac transplantation for patients with myocarditis.  相似文献   
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Non-selective inhibition of monoamine oxidase (MAO) enzymes (ie, isoforms A and B) in the brain are associated with clinically significant antidepressant effects. In the US, the selegiline transdermal system (STS; EMSAM) is the first antidepressant transdermal delivery system to receive Food and Drug Administration (FDA) approved labeling for the treatment of major depressive disorder (MDD). Currently, the use of orally administered MAO inhibitor antidepressants (eg, phenelzine, tranylcypromine) is limited by the risk of tyramine-provoked events (eg, acute hypertension and headache, also known as the “cheese reaction”) when combined with dietary tyramine. The selegiline transdermal system is the only MAOI available in the US for the treatment of MDD that does not require dietary restriction at the clinically effective dose of 6 mg/24 hours. Delivery of selegiline transdermally (EMSAM®) bypasses hepatic first pass metabolism, thereby avoiding significant inhibition of gastrointestinal and hepatic MAO-A activity (ie, reduced risk of tyramine-provoked events) while still providing sufficient levels of selegiline in the brain to produce an antidepressant effect. At dosages of 6–12 mg/24 hours, EMSAM has been shown to improve symptoms of depression, have good tolerability, and have high rates of medication adherence. However, at higher doses of EMSAM (ie, 9 mg/24 hours or more), dietary restriction of tyramine intake is recommended. The introduction of EMSAM overcomes many of the safety concerns affiliated with the conventional oral MAO inhibitors and EMSAM may be considered another strategy for the treatment of MDD, especially in patients who cannot tolerate oral antidepressants, are poorly adherent, who present with atypical depressive symptoms, or have failed other antidepressants.  相似文献   
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Introduction Obese individuals may have normal insulin–glucose homeostasis, insulin resistance, or diabetes mellitus. Whereas gastric bypass cures insulin resistance and diabetes mellitus, its effects on normal physiology have not been described. We studied insulin resistance and β-cell function for patients undergoing gastric bypass. Methods One hundred thirty-eight patients undergoing gastric bypass had fasting insulin and glucose levels drawn on days 0, 12, 40, 180, and 365. Thirty-one (22%) patients with diabetes mellitus were excluded from this analysis. Homeostatic model of assessment was used to estimate insulin resistance, insulin sensitivity, and β-cell function. Based on this model, patients were categorized as high insulin resistance if their insulin resistance was >2.3. Results Body mass index did not correlate with insulin resistance. Forty-seven (34%) patients were categorized as high insulin resistance. Correction of insulin resistance for this group occurred by 12 days postoperatively. Sixty (43%) patients were categorized as low insulin resistance. They demonstrated an increase of β-cell function by 12 days postoperatively, which returned to baseline by 6 months. At 1 year postoperatively, the low insulin resistance group had significantly higher β-cell function per degree of insulin sensitivity. Conclusions Adipose mass alone cannot explain insulin resistance. Severely obese individuals can be categorized by degree of insulin resistance, and the effect of gastric bypass depends upon this preoperative physiology.  相似文献   
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Twenty patients received transduodenal sphincteroplasty and transampullary septectomy between 1987 and 1993. Seven patients had post-cholecystectomy pain which was much improved or abolished in 5 of 7 patients at a mean follow-up of 4 years and 5 months. Four of five patients with chronic pancreatitis were improved at 3 years and 2 months. Three of five patients with recurrent acute pancreatitis were improved at 4 years and 5 months. One of three patients with chronic abdominal pain of hepatobiliary origin was improved at 3 years. Transduodenal sphincteroplasty and transampullary septectomy can relieve pain in patients with post-cholecystectomy pain, recurrent acute pancreatitis, chronic pancreatitis, and chronic abdominal pain of hepatobiliary origin, presumably by improving drainage of the obstructed ducts.  相似文献   
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PURPOSE: The purpose of our study was to obtain a clear understanding of the various diagnoses within the closed neural tube defect (NTD) groups included in the large database of clients in our Spina Bifida Clinic and a clear picture of the outcomes for the various NTD groups. METHODS: One hundred and four clients with closed NTD were categorized using a classification system devised by Tortori-Donati et al. Various clinical markers were investigated, including ambulation and the need for orthoses and wheelchairs. RESULTS: Most clients are ambulatory, requiring an orthoses, but not a wheelchair, despite the high incidence of ankle/foot abnormalities. CONCLUSIONS: This classification system has enhanced our knowledge of this group of clients, provided a greater understanding of the varied outcomes of these children and clinical management required.  相似文献   
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