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101.
Two variants of a continuous recognition training procedure were designed in order to query 2 forms of spatial memory. A continuous reinforcement condition (reflecting perceptual memory) and a differential reinforcement condition (reflecting episodic-like memory) were used to test rats on a 12-arm radial maze. After total hippocampal lesions, rats demonstrated intact performance on the continuous reinforcement condition, but impaired performance on the differential reinforcement condition. After parietal lesions, rats demonstrated the reverse pattern of performance: impaired performance on the continuous reinforcement condition and intact performance on the differential reinforcement condition. Thus, a double dissociation appears to exist between parietal cortex and hippocampus for the continuous reinforcement condition (reflecting perceptual memory) versus the differential reinforcement condition (reflecting episodic memory) for spatial location information.  相似文献   
102.
Human cytomegalovirus (HCMV) DNA can be detected in different compartments of human milk. A protocol for the preparation of milk whey free of fat and cells for the detection of human cytomegalovirus (HCMV) by nested PCR is presented. This is based upon the experience of the separation of more than 200 milk specimens of healthy seropositive breast feeding mothers. HCMV DNA could be detected in freshly centrifuged and filtrated milk whey specimens without contamination by cellular DNA. In limiting dilution experiments using HCMV plasmid DNA, the effect of different DNA extraction procedures from native milk and milk whey on the detection limit of cytomegaloviral DNA was demonstrated. About 200 viral genome equivalents/ml in milk whey or native milk were detectable by classical organic phenol/chloroform extraction or a spin column method, respectively. The detection of viral DNA in milk cells depended on a minimum number of milk cells (105–2×105) available for DNA extraction. In contrast to the findings of cytomegaloviral DNA in native sera or plasma of immunosuppressed patients we failed to amplify low level viral DNA from native breast milk by nested PCR due to an inhibition of Taq polymerase by lipid components. Finally, the course of cell associated and cell free DNAlactia was monitored. Analyzing sequential milk specimens, in some cases the presence of HCMV DNA in colostrum could be demonstrated. DNAlactia of milk cells and whey was partially discordant. Onset (week 1–4 after delivery) and duration (2 weeks up to more than 3 months) of DNAlactia showed distinct individual patterns. The methods described, allow further analysis of the mechanisms involved in the postnatal HCMV transmission by breast feeding seropositive mothers.  相似文献   
103.
104.
To evaluate whether inflammation-like mechanisms present in the brain of Alzheimer's disease (AD) patients are reflected in the periphery, the expression of CD11b in peripheral blood neutrophils and the expression and activity of inflammatory markers in cultured skin fibroblasts were examined. We found significantly higher levels of CD11b in neutrophils from sporadic AD patients than in controls and this elevation was positively correlated with disease severity and progression rate of mental decline. Cultured skin fibroblasts from familial (FAD) and sporadic AD patients and from controls were immunopositive for both isoforms of cyclooxygenase with no differences between groups. In unstimulated culture, the production of prostaglandin-E2 in the medium was significantly higher in fibroblasts from sporadic AD and FAD patients than in controls, and this elevation was reverted by the addition of 25 microM of ibuprofen. Our findings provide further evidence of the presence of inflammatory and immuno-related markers in the periphery of AD patients and support those studies indicating the beneficial effects of anti-inflammatory therapy in AD.  相似文献   
105.
Fifty-four subjects, aged between 20 and 35 years, divided into two subgroups, respectively 30 healthy subjects (17 males and 13 females) and 24 subjects with "gonalgia sine materia" (13 males and 11 females) underwent isokinetic exercise test in order to compare their dominant limb with the not dominant one as regard as the strength of extensor and flexor muscles of the knee. No statistically significant difference was found in any of the studied parameters in the comparison between the dominant limb and the not dominant one, both within the subgroup of healthy subjects and within the subgroup of subjects with "gonalgia sine materia". Authors conclude that psychological features may play a preeminent role in the genesis, as well as in the maintenance of "gonalgia sine materia", thus confirming previous data available in medical literature.  相似文献   
106.
Mutations of the LMNA gene encoding the lamin A and C nuclear envelope proteins cause an autosomal dominant form of dilated cardiomyopathy (DCM) with atrioventricular block (AVB). The aim of this study was to investigate ultrastructural nuclear membrane changes by conventional electron microscopy and protein expression by immuno-electron microscopy in the heart of patients with DCM and AVB due to LMNA gene mutations. Four immunohistochemical techniques were used: pre-embedding and post-embedding in Epon-Araldite resin and London Resin White (LRW), with and without silver enhancement. Parallel light microscopy immunohistochemistry studies were performed. Conventional electron microscopy showed a loss of integrity of the myocyte nuclei with blebs of the nuclear membrane, herniations and delamination of the nuclear lamina and nuclear pore clustering. Post-embedding LRW was the most informative technique for morphology and immuno-labelling. Immuno-labelling was almost absent in the nuclear envelope of patients with LMNA gene mutations, but intensely present in controls. The loss of labelling selectively affected myocyte nuclei; the endothelial cell nuclei were immunostained in patients and controls. Light immunohistochemistry confirmed the results. These findings confirm the hypothesis that LMNA gene defects are associated with a loss of protein expression in the selective compartment of non-cycling myocyte nuclei.  相似文献   
107.
Micronuclei and other biomarkers were evaluated in oral cells from 11- to 16-year-old girls living in a foster home in the central area of México City. Variables analyzed for possible association with these biomarkers include smoking habits, body mass index, metabolic polymorphisms for NAT1 and GSTM1 and whether the cells were obtained from the cheek or pharynx. The results indicated that individuals having the NAT1*10 homozygous genotype showed a significant increase in chromatin buds and binucleated cells. When the damage in the cheek was compared with damage in the pharynx, a significant increase in micronuclei and binucleated cells was found for the latter tissue in all the individuals analyzed.  相似文献   
108.
This prospective multisite Phase III clinical trial (Miami, New York, New Jersey) investigated the long-term (one year) effects of a 10-week group cognitive-behavioral stress management/expressive supportive therapy (CBSM+) intervention on disadvantaged minority women living with AIDS. The CBSM+ intervention consisted of 10-weekly group session of stress management, cognitive-behavioral skill training, relaxation techniques and expressive-supportive therapeutic strategies. The primary study outcome was self-reported depression scores as measured by the BDI. The CBSM+ Group intervention significantly decreased depression scores on the BDI for women following the intervention and maintained the decreased level at one-year follow-up.  相似文献   
109.
In recent years, major and widely accepted information security understandings and achievements confirm that the problem is complex. They clarify that technologies are fundamental tools, but management processes have even bigger relevance, as also prestigious international magazines dossier clearly explained recently. Such a magazine attention outlines the wide impact that the subject has on watchful decision makers. ISO17799 is an emerging standard in information security. In principle there are no reasons for considering it not applicable to the health care sector. In practice, because of both the just conceptual level of the standard and the peculiarities of the health care data and institutions, a lot of analysis and design work need to be invested any time a health care institution decides to deal with the subject. CEN/ENV 12924 is another emerging standard certainly more on the spot of the health care. Nevertheless, it also asks for evident further investigation. The practical case of information security design, implementation, management, and auditing inside a multi-specialty provincial Italian hospital will be described.  相似文献   
110.
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