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31.
Atrophoderma of Pasini and Pierini (APP) is a rare and distinctive form of dermal atrophy of uncertain origin. In only one previous report have immunopathologic methods been used to study a case of atrophoderma of Pasini and Pierini, and on the basis of the results obtained it was concluded that immunologic mechanisms were relevant to the pathogenesis of the condition. A detailed investigation of a case of atrophoderma of Pasini and Pierini was conducted using immunofluorescence and immunoperoxidase techniques. The epidermal Langerhans cells were abundant and expressed polyclonal immunoglobulin M on the cell-surface membrane. Biopsy of the same lesion was repeated 6 months later and revealed staining for immunoglobulins A and M and also for C3. This pattern of staining could not be reproduced in a range of other atrophic or scarring cutaneous lesions. Immunophenotypic analysis of the mild perivascular mononuclear cell infiltrate revealed an aberrant T-cell phenotype of uncertain significance.  相似文献   
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This study examined the responsivity of depressives' behavior to contingent social feedback within the framework of Coyne's and Lewinsohn's models of depression. Subjects included 10 depressed inpatients, 8 nondepressed psychiatric inpatients, and 10 nondepressed individuals. Each subject participated in two structured interactions with an experimenter in baseline phases and phases in which ongoing contingent feedback was provided by a pair of observers. The results revealed that the behavior of all three subject groups was responsive to the feedback in both interactions. The results are consistent with past research demonstrating social skills problems among depressed individuals but do not support the notion of a social skill deficit in depression. The results are consistent with Coyne's model of depression and suggest that the problematic social behavior often associated with depression may be modifiable by immediate veridical feedback from others.  相似文献   
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L D Fricker  E Herbert 《Brain research》1988,453(1-2):281-286
Several diverse species contain an enzyme with many properties in common with those of bovine carboxypeptidase E (CPE), a neuropeptide processing carboxypeptidase B-like enzyme. This enzyme has been designated EC 3.4.17.10, and is also known as enkephalin convertase and carboxypeptidase H. All tissues that are known to contain bioactive peptides also contain CPE-like enzymatic activity. In Xenopus laevis, enzyme activity is highest in the brain and pituitary, lower in the skin, and undetectable in liver and gut. In Aplysia californica, enzyme activity is highest in the atrial gland, but is also present in moderate amounts in the various neural tissue. CPE extracted from human, bovine, mouse, Xenopus, shark, and Aplysia neural tissue is substantially purified using substrate affinity chromatography and concanavalin A sepharose columns. The partially purified enzyme from all species examined possess very similar enzymatic properties. These properties include a pH optimum of 5.6, a stimulation by cobalt chloride, and an inhibition by chelating agents (1,10-phenanthroline). Arginine-derived active site-directed inhibitors show similar inhibition constants (Ki's) towards enzyme from the various species, whereas lysine-derived inhibitors are substantially less potent towards the Aplysia carboxypeptidase than towards enzyme isolated from the other species. The similar properties of the carboxypeptidase isolated from the various species suggests that a CPE-like is involved in the biosynthesis of many peptide neurotransmitters and hormones in a wide range of organisms.  相似文献   
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The inhibitory effects of aminobeclamide (N-(p-aminobenzyl)-beta-chloropropionamide) on socially offensive behaviour has been studied and compared with those of the parent drug beclamide (N-benzyl-beta-chloropropionamide). Following oral administration in mice which had been individually housed for a 28 day period then paired with normal group-housed opponents, aminobeclamide and beclamide both produced significant and dose-related inhibition of socially offensive behaviour. Aminobeclamide (20-150 mg kg-1 p.o.) and beclamide (50-250 mg kg-1 p.o.) gave increased offense onset latency whilst at the same time they reduced the incidence of offense encounters/animal and decreased the group percentage of animals displaying offense behaviour. It is likely that both drugs have similar monoamine modifying effects though this animal study suggests that aminobeclamide is 1.5 to 2.7 times more potent than beclamide against socially offensive behaviour.  相似文献   
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The catechol-O-methyltransferase (COMT) Val158Met polymorphism modulates executive functions and working memory and recent neuroimaging studies implicate an association with emotional processing. We examined the relationship between the COMT Val158Met polymorphism and facial emotion recognition and differentiation in 100 healthy individuals. Compared to Met homozygosity, Val homozygosity was associated with better and faster recognition of negative facial expressions such as anger and sad. Our study provides evidence for a possible influence of the COMT polymorphism on emotion recognition abilities in healthy subjects. Additional research is needed to further define the neurocognitive phenotypes associated with COMT polymorphisms.  相似文献   
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BACKGROUND: Previous research found an association between single nucleotide polymorphisms (SNPs) in the promoter region of DRD4 and statistically derived phenotypes generated from attention-deficit/hyperactivity disorder (ADHD) symptoms. We sought to replicate this finding by using the same methodology in an independent sample of ADHD individuals. METHODS: Four SNPs were genotyped in and around DRD4 in 2631 individuals in 642 families. We developed a quantitative phenotype at each SNP by weighting nine inattentive and nine hyperactive-impulsive symptoms. The weights were selected to maximize the heritability at each SNP. Once a quantitative phenotype was generated at each SNP, the screening procedure implemented in PBAT was used to select and test the five SNPs/genetic model combinations with the greatest power to detect an association for DRD4. RESULTS: One of the four SNPs was associated with the quantitative phenotypes generated from the ADHD symptoms (corrected p-values = .02). A rank ordering of the correlation between each of the ADHD symptoms and the quantitative phenotype suggested that hyperactive-impulsive symptoms were more strongly correlated with the phenotype; however, including inattentive symptoms was necessary to achieve a significant result. CONCLUSIONS: This study partially replicated a previous finding by identifying an association between rs7124601 and a quantitative trait generated from ADHD symptoms. The rs7124601 is in linkage disequilibrium (LD) with the SNPs identified previously. In contrast to the previous study, this finding suggests that both hyperactive-impulsive and inattentive symptoms are important in the association.  相似文献   
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