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Human herpesvirus-6 (HHV6) is a lymphotropic virus genetically related to human cytomegalovirus (CMV) and for which two variants, A and B, have been distinguished. Human CMV is usually cultivated with human fibroblasts (HF). The lack of cell lines useful for HHV6 isolation and propagation led us to investigate whether HHV6 variants A and B could infect HFs as CMV does. Isolates of HHV6 variants A and B were used to infect MRC-5 HFs. HHV6 infection was detected by means of immunoperoxidase assay using three specific monoclonal antibodies. HHV6-specific antigens were detected in 88 and 38% of cases after infection with variants A and B, respectively. The highest number of HHV6-antigen-positive cells was obtained at 4-5 days p.i. The titre of HHV6 stocks was determined in parallel by immunoperoxidase assay on HFs and by observation of cytopathic effect using serial dilutions on peripheral blood mononuclear cells (PBMC). The number of infectious particles inducing the appearance of antigen-positive HF cells was consistently lower than the titre of virus stocks, expressed as TCID50. The amount of HF-associated HHV6 DNA was measured using limiting dilution PCR assay; it was significantly increased during 4-day infection in the case of variant A but not variant B. The yield of virus from infected HFs was demonstrated only for variant A by the serial propagation of virus from HFs to PBMCs and by the increase in cell-free HHV6 DNA in HF culture supernatant. Our results show that HHV6 can reproducibly infect HFs, albeit at a low level, and that HFs are more permissive to variant A than to variant B, as reported previously for PBMCs and human T-cell lines.  相似文献   
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The subjects were 55 undergraduates enrolled in psychology classes and classified by their scores on the Human Information Processing Survey as having preferences of left hemisphericity (n = 17), right (n = 19), and integrated hemisphericity found between left- and right-hemisphericity groups with the left-hemisphericity group obtaining higher course grades.  相似文献   
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We studied the use of functional MRI (fMRI) with visual stimulation in nine patients with unilateral optic neuritis. Eight healthy subjects served as controls. Patients showed reduced activation upon stimulation of the affected eye, on average 33% (range 0 to 156%) of the average monocular activation in the control group. Decreased activation was also seen for the unaffected eye (61% of control values, range 3 to 133%). We conclude that fMRI with visual stimulation is feasible in patients with optic neuritis and deserves future study.  相似文献   
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Both neural networks and fuzzy logic systems exhibit human-like mental processing. The similarities and dissimilarities of these two technologies, such as multi-layer operations of neural networks and max-min operation in fuzzy logic systems, make apparent that there are advantages to combining them. However, this was not done until the late 1980's. Surveying the literature revealed eight different approaches to combining the merits of fuzzy logic systems and neural networks.  相似文献   
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Sustained iontophoresis of NMDA potentiated visual responses for minutes after the application in 16 of 38 cells (42%), peaking 3 min after the end of the application and declining to control levels within 12 min. Potentiation was also seen after application of ACPD (36%, n = 14) and AMPA (29%, n = 14), but not after application of ACh (n = 20). ACh also excites dLGN cells, but does not interact with amino acid receptors, and ACh receptors are not directly involved in the transmission of visual information. We suggest that this modulation is a form of visually induced potentiation which permits dynamic modification of the strength of visual information to be relayed to the cortex depending upon the history of previous activity levels.  相似文献   
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While home care agencies work to increase productivity and decrease costs, it is easy to lose sight of the value of employees. Because home care aides are seldom in the office, their value to the organization may get overlooked. In this article, one home care agency shares ways to build team spirit among the home care aides and empower them to be better employees. The result has been increased productivity, improved morale, and a more stable workforce.  相似文献   
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A multisite, longitudinal study of patients undergoing inpatient alcohol and drug dependence treatment was conducted in private inpatient facilities, consisting of 4339 subjects from 38 independent programs enrolled in a national addiction treatment outcomes registry. Structured interviews were conducted upon admission, including documentation of current alcohol/drug disorder (DSM-III-R) and lifetime diagnosis of major depressive syndrome; structured interviews were conducted prospectively at 6- and 12-month follow-up periods. The prevalence rate of lifetime diagnosis of major depression in the sample was 39%. Comorbidity varied according to gender and substance of choice. Lifetime depressive symptoms did not correlate with differential length-of-stay, treatment completion, or follow-up consent and, at best, were very weakly associated with follow-up contact. Patients diagnosed with lifetime depression showed the same frequency of participation in posttreatment continuing care: they also showed statistically significant reductions in job absenteeism, inpatient hospitalizations, and arrest rates pre- vs. posttreatment comparable to those of patients without lifetime depression diagnosis. Lifetime major depressive syndrome was not a predictor of outcome in response to abstinence-based treatment. Involvement in posttreatment continuing care accounted for far greater outcome variance. Posttreatment vs. pretreatment factors may be more decisive in influencing risk for relapse.  相似文献   
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