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91.
This study assessed the joint effects of defensiveness and frontal asymmetry in predicting symptoms of depression and anxiety. Depression symptoms were measured with the Beck Depression Inventory (BDI) and anxiety symptoms with the Taylor Manifest Anxiety Scale (TMAS). Defensiveness was assessed with both the Marlowe Crowne Social Desirability Scale (MCSD) and the Eysenck Personality Questionnaire L scale (EPQL). Participants completed two EEG recording sessions 3 weeks apart. Six baselines, three eyes open and three eyes closed, were recorded in each session. Alpha power (8–13 Hz) was computed and log transformed. RL asymmetry was computed at eight pairs of homologous sites for aggregated data. Defensiveness (EPQL and MCSD scores) and depression symptoms (BDI) were assessed at the beginning of the first session. L and MCSD correlated positively with anterior RL asymmetries. For both scales, the highest correlations were observed at F8–F7. L interacted with F8–F7 asymmetry to predict depressive symptoms. Among left frontally active individuals, there was trend toward a negative correlation between L and BDI. Among the right frontally active individuals, the correlation between L and the BDI was positive. MCSD did not moderate the relation between F8–F7 asymmetry and BDI. The results are consistent with the hypothesis that defensiveness protects against symptoms of depression in the context of left frontal activity, and serves as a diathesis for depression in the context of right frontal activity. High-defensive individuals who are right frontally active may represent “failed repressors,” i.e. individuals for whom defensiveness does not protect against depression, and may even exacerbate it.  相似文献   
92.
In order to develop a genetic study of human laterality, we conducted an exploratory study concerning one aspect of this phenotype: lattice analysis was used to determine whether the structure of manual preference was the same for right- and left-handers. The study highlights the links between two sets — participants and actions — describing binary data, by ordering them dually along a Galois lattice: participants were ordered according to subsets of actions for which they used only their writing hand, while actions were ordered according to sub-groups using their writing hand to perform them. The twelve item questionnaire of Annett was analysed in two samples of 94 adult right-hand and 31 left-hand writers. The items did not have the same categorical impact for the two groups of left- and right-hand writers. The behaviour of right-handers appeared globally more stereotyped. On the contrary, left-handed profiles were nearly all distinct. To explore these conclusions more thoroughly in the general population would certainly require greater samples. Nevertheless in both cases the observed structures were highly dimensional, a result that would grow stronger as the group sizes increase. Hence whereas some questionnaires purport to evaluate laterality along an unidimensional continuum, the present analysis questions such a strong assumption providing evidence to the contrary.  相似文献   
93.
Favorable long-term patient outcome after insertion of a left ventricular assist device (LVAD) as a bridge to recovery or destination therapy for the treatment of end-stage cardiomyopathy is adversely affected by pathophysiologic changes affecting the heart. Alterations in the native aortic valve apparatus, specifically aortic valve cusp fusion, is an example of such a phenomenon and may especially affect patients in cases of bridge to recovery, a rare but reported event. A retrospective review of the last 33 LVAD placements at our institution was conducted, including reviews of operative reports and pathologic examinations of the native hearts. Seven hearts were found to have varying degrees of aortic valve cusp fusion after chronic LVAD support (63-1, 339 days). Five of these patients had native aortic valves, and two had bioprosthetic valves. The left ventricular outflow tracts in two patients were surgically occluded at the time of LVAD insertion. Aortic valve cusp fusion occurs in roughly 25% of patients on chronic LVAD support. This phenomenon may prove to be clinically significant by creating a potential source of emboli and infection. In addition, in the case of myocardial recovery, left ventricular outflow tract obstruction could limit parallel flow and produce suprasystemic ventricular pressures that in turn would elevate left ventricular end diastolic pressures. The latter may contribute to further myocardial injury, ultimately limiting the ability of an otherwise recovered heart to be weaned from LVAD support.  相似文献   
94.
Multidrug-resistant Salmonella Newport with decreased susceptibility to ceftriaxone (MDR-AmpC) is becoming increasingly common in its food animal reservoirs and in humans. Few data exist on rates of antimicrobial use or differences in clinical outcomes in persons infected with MDR-AmpC or other Salmonella strains. We conducted a case-comparison analysis of data from a multistate population-based case-control study to identify antimicrobial treatment choices and differences in clinical outcomes in those infected with MDRAmpC compared to pansusceptible S. Newport. Of isolates from 215 laboratory-confirmed S. Newport cases, 54 (25%) were MDR-AmpC, 146 (68%) were pansusceptible, and 15 (7%) had other resistance patterns; 146 (68%) patients with S. Newport were treated with antimicrobial agents and 66 (33%) were hospitalized. Over two-thirds of cases at low-risk for serious complications received antimicrobial therapy, most commonly with fluoroquinolones, to which this strain was susceptible. There were no significant differences in symptoms, hospitalization, duration of illness, or other outcomes between the persons infected with MDR-AmpC and pansusceptible S. Newport. Although currently prevalent MDR-AmpC S. Newport strains remains susceptible to the antimicrobial most commonly prescribed for it, continued efforts to reduce unnecessary use of antimicrobial agents in food animals and humans are critical to prevent further development of resistance to quinolones and cephalosporins, which is likely to lead to substantial adverse outcomes.  相似文献   
95.
Ovarian cancer remains the fifth leading cause of cancer death for women in the United States. In this study, the gene expression of 20 ovarian carcinomas, 17 ovarian carcinomas metastatic to the omentum, and 50 normal ovaries was determined by Gene Logic Inc. using Affymetrix GeneChip HU_95 arrays containing approximately 12,000 known genes. Differences in gene expression were quantified as fold changes in gene expression in ovarian carcinomas compared to normal ovaries and ovarian carcinoma metastases. Genes up-regulated in ovarian carcinoma tissue samples compared to more than 300 other normal and diseased tissue samples were identified. Seven genes were selected for further screening by immunohistochemistry to determine the presence and localization of the proteins. These seven genes were: the beta8 integrin subunit, bone morphogenetic protein-7, claudin-4, collagen type IX alpha2, cellular retinoic acid binding protein-1, forkhead box J1, and S100 calcium-binding protein A1. Statistical analyses showed that the beta8 integrin subunit, claudin-4, and S100A1 provided the best distinction between ovarian carcinoma and normal ovary tissues, and may serve as the best candidate tumor markers among the seven genes studied. These results suggest that further exploration into other up-regulated genes may identify novel diagnostic, therapeutic, and/or prognostic biomarkers in ovarian carcinoma.  相似文献   
96.
Regulation of nuclear factor of activated T cells-c2 (NFATc2) gene expression is not clearly defined. We previously reported reduced NFATc2 protein expression in cord blood T lymphocytes. Here we show that NFATc2 expression in T cells is dependent in part on the presence of IFN-gamma during primary stimulation, as blocking of IFN-gamma blunted NFATc2 protein and mRNA upregulation. Conversely, addition of exogenous IFN-gamma during stimulation resulted in increased expression of NFATc2 in cord blood T lymphocytes. This correlated with rescue of deficient IFN-gamma expression by cord blood T cells. Rescue of IFN-gamma expression in cord blood T cells was dependent on the presence of antigen-presenting cells, as addition of IFN-gamma during stimulation of purified cord blood T cells did not result in an increase of IFN-gamma expression, and depletion of monocytes ablated the rescue of IFN-gamma expression. Our results point to impaired function in the antigen-presenting cell population of cord blood, playing a role in the hyporesponsiveness of T cells.  相似文献   
97.
We investigated a novel polyepoxide crosslinker that was hypothesized to confer both material stabilization and calcification resistance when used to prepare bioprosthetic heart valves. Triglycidylamine (TGA) was synthesized via reacting epichlorhydrin and NH(3). TGA was used to crosslink porcine aortic cusps, bovine pericardium, and type I collagen. Control materials were crosslinked with glutaraldehyde (Glut). TGA-pretreated materials had shrink temperatures comparable to Glut fixation. However, TGA crosslinking conferred significantly greater collagenase resistance than Glut pretreatment, and significantly improved biomechanical compliance. Sheep aortic valve interstitial cells grown on TGA-pretreated collagen did not calcify, whereas sheep aortic valve interstitial cells grown on control substrates calcified extensively. Rat subdermal implants (porcine aortic cusps/bovine pericardium) pretreated with TGA demonstrated significantly less calcification than Glut pretreated implants. Investigations of extracellular matrix proteins associated with calcification, matrix metalloproteinases (MMPs) 2 and 9, tenascin-C, and osteopontin, revealed that MMP-9 and tenascin-C demonstrated reduced expression both in vitro and in vivo with TGA crosslinking compared to controls, whereas osteopontin and MMP-2 expression were not affected. TGA pretreatment of heterograft biomaterials results in improved stability compared to Glut, confers biomechanical properties superior to Glut crosslinking, and demonstrates significant calcification resistance.  相似文献   
98.
Pro-B cells are early B-cell progenitors that retain macrophage potential. We have studied MHC class II molecules and invariant chain inducibility on four class II negative mouse pro- B-cell clones. We analyzed the effects of IL-4 and IFN-γ, which represent the major inducers of class II in the B-lymphoid and monocytic/macrophage lineages, respectively. After 48 h of treatment with either cytokine, three pro-B-cell clones (C2.13, A1.5, and F2.2) expressed intracellular invariant chain and cell-surface class II molecules. One clone (D2.1) remained negative. As already reported, more differentiated 70Z/3 pre-B cells were inducible by IL-4 only. These data suggest that the induction of class II and invariant-chain genes are subject to regulation throughout B-cell differentiation.  相似文献   
99.
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