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61.
Administration of lead (at 300 and 1000 ppm) in the maternal drinking water from conception to weaning impaired the antinociceptive activity of morphine in 10-day-old neonatal rats. Blood lead levels in these animals were below 50 μ/100 ml in the high lead dose group and below 35 μg/100 ml in the low lead dose group. The differences in the antinociceptive potency of morphine between normal and lead-exposed animals were not observed at later time points (21 and 30 days). It is suggested that lead disrupts the development of opioid receptor systems in the central nervous system and that this disruption occurs early in development.  相似文献   
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Records of 346 patients were studied to determine the reliability and diagnostic value of pancreatic scanning. In 157 the pancreatic diagnosis was established subsequent to scanning. The scan was abnormal in 28 of 34 patients (82%) with pancreatic neoplasm, and in 21 of 26 patients (81%) with chronic pancreatitis. Of 71 with normal scans, 56 (79%) had a normal pancreas, and 15 had pancreatic disease (a false negative rate of 21%). Of the 86 with abnormal scans, the pancreas was diseased in 56 (65%), and of the others, 14 had extrapancreatic conditions known to be associated with a high incidence of scan abnormalities. In obstructive jaundice all 21 patients with pancreatic carcinoma had abnormal scans (and the scan accurately diagnosed all four cases of bile duct carcinoma). A normal scan reliably indicated that the cause of jaundice was outside the pancreas. In chronic abdominal pain an abnormal scan was unreliable, but a normal scan excluded pancreatic disease with reasonable accuracy.  相似文献   
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Orbital extension of retinoblastoma: a clinicopathological study   总被引:2,自引:0,他引:2  
We have studied all cases of orbital extension of retinoblastomas at the Edward S. Harkness Eye Institute in New York since 1925. Only 9.4% of the patients lived more than 2 years after diagnosis. Orbital retinoblastoma is frequently associated with systemic metastases. We emphasize the significance of massive choroidal involvement and periemissarial extension. Careful handling of the enucleation specimen at the time of surgery and during histologic preparation is important to avoid cell spillage and artifacts. Treatment should be early, multidisciplinary and include adjuvant chemotherapy.  相似文献   
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Inflammatory myofibroblastic tumours (IMTs) are an uncommon spindle cell neoplasm with a dense inflammatory infiltrate, usually encountered in children. IMTs of the central nervous system are extremely rare. This report describes the case of an IMT in a 61 year old man, in the pineal region. The tumour was completely excised, and immunohistochemistry demonstrated anaplastic lymphoma kinase 1 expression. There was no tumour recurrence during 18 months of follow-up. Our case extends both the age range and sites of occurrence of this rare tumour.  相似文献   
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We examined whether deficits in attention and perceptual encoding as well as psychological defensiveness were associated with impaired awareness of disorder in schizophrenia. The Scale for Unawareness of Mental Disorder (SUMD) was administered to 52 outpatients with a recent onset of schizophrenia approximately 1-2 months following hospital discharge. Two versions of the Continuous Performance Test (CPT) were used to measure attentional impairment--the Degraded Stimulus CPT (DS-CPT) and a memory-load version (3-7 CPT). Three scales from the Minnesota Multiphasic Personality Inventory were used as indicators of psychological defensiveness: Scales L (Lie), K (Correction), and R (Repression). The Classification and Regression Tree (CART) program, a nonparametric statistical method, was used to identify relationships among multiple predictor variables and to provide optimal splitting scores for each predictor variable. Different combinations of poor target discrimination (d') on the 3-7 CPT and a cautious response style on the DS-CPT were associated with the three levels of overall unawareness of having a mental disorder. For nonpsychotic patients, better target discrimination (d') on the 3-7 CPT tended to be associated with better awareness of having a mental disorder. In contrast, unawareness among the patients who were psychotic at the time of the SUMD administration was not discriminated by attentional measures, but was associated with a combination of two measures of psychological defensiveness from the MMPI reflecting guardedness, psychological suppression, attempting to present oneself in a socially desirable light, and social acquiescence. Generally similar associations were found for two other dimensions of poor insight: unawareness of the beneficial effects of antipsychotic medication, and inability to attribute unusual thoughts and hallucinatory experiences to a mental disorder.  相似文献   
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A case of transfusion-transmitted malaria was identified in a 50-year-old male patient with sickle cell disease. The donor was Ghanaian, but had migrated to the UK some years previously and had not left the UK for 8 years. The donor met all of the extant donor selection guidelines [1] and a donation was consequently collected. However, on subsequent investigation of the case, the donor was found to be parasitaemic and have high titre malarial antibodies. As a result of this case, changes to the United Kingdom donor selection guidelines have been proposed. These changes will prevent any such further transmissions.  相似文献   
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