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91.
Transhepatic dilatation of choledochoenterostomy strictures 总被引:2,自引:0,他引:2
92.
A behavioral window on the mind of the market: an application of the response time paradigm 总被引:2,自引:0,他引:2
This article focuses on the role of implicit knowledge consumers have about particular brands, products or names. The major findings of several studies, conducted at the Mind of the Market Laboratory at Harvard Business School, are presented with specific emphasis on studies in which response time measurements were the core method. The results revealed that implicit measures provide a rich understanding of the meaning conveyed by a product or brand. Moreover, there is also considerable evidence that implicit measures may be better than traditional explicit measures as predictors of consumer behavior. We discuss the implications for the study of consumer behavior and the importance of combining several methods including neuroimaging, which has received recent attention by marketers, economists and social scientists. 相似文献
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94.
Raybagkar DA Patchipulusu S Mast AE Hall CL 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2004,50(4):301-305
Recombinant tissue factor pathway inhibitor (rTFPI) was immobilized on collagen impregnated (CI) knitted Dacron surfaces and its resistance to fibrin deposition evaluated following exposure to nonanticoagulated whole blood. Recombinant TFPI readily adsorbed to the CI Dacron surface and maintained its inhibitory activity. Under static conditions, rTFPI treated CI Dacron showed little fibrin deposition when compared with untreated surfaces. Treated samples exposed to flowing native blood at wall shear rates of 100 or 200 sec(-1) also demonstrated reduced fibrin deposition (up to 56%) compared with untreated samples. To assess the relative roles of the contact and tissue factor pathways in fibrin formation on artificial grafts, flow studies were performed with whole blood containing corn trypsin inhibitor, a potent inhibitor of FXIIa and contact activation. Corn trypsin inhibitor reduced fibrin deposition on untreated CI Dacron by 40%. Immobilized rTFPI alone, or corn trypsin inhibitor in combination with immobilized rTFPI, reduced fibrin deposition by 58% and 61%, respectively. These data suggest that immobilized rTFPI slows fibrin deposition on the vascular graft material by inhibiting both the contact pathway and blood borne tissue factor procoagulant activity arising from either the alternatively spliced form of tissue factor or from tissue factor containing microparticles. 相似文献
95.
STUDY OBJECTIVES: Peripheral arterial tonometry (PAT) is a sensitive measure of moment-to-moment changes in sympathetic activity and reliably identifies arousals in adult subjects. We investigated whether PAT events during sleep are associated with visually recognizable electroencephalographic arousals in healthy children and in children with sleep-disordered breathing. DESIGN: Prospective cohort. SETTING: Pediatric Sleep Research Laboratory. PARTICIPANTS: Twenty children with obstructive sleep apnea syndrome, 20 children with mild sleep-disordered breathing, and 20 control children with a mean age of 7.6 +/- 2.6 years (range: 5.7-16.5 years); 53% of children were boys. INTERVENTIONS AND MEASUREMENTS: Polysomnographic evaluation in the sleep laboratory with concomitant recording of PAT. PAT events were defined as attenuations from immediately preceding baseline of 20% to 50% (PAT20) and > 50% (PAT50) for at least 5 seconds and the indexes calculated per hour of sleep time that included good-quality PAT signals. Total PAT index (the sum of PAT20 index and PAT50 index) was also calculated. RESULTS: Total PAT index correlated with total arousal index and spontaneous arousal index (r = 0.55, P < .0001, r = 0.64, P < .001, respectively), especially in the group with obstructive sleep apnea syndrome (r = 0.71, P < .0001). The sensitivity and specificity of PAT for identifying electroencephalographic arousals were 95% and 35%, respectively. The PAT device identified pathologic arousals indexes (> or = 16 per hour) (area under the curve 0.79, P = .002). Thirty-five percent of respiratory events (eg, obstructive apnea or hypopnea) were associated with a visual electroencephalographic arousal, compared to 92% being associated with PAT attenuation events. CONCLUSIONS: Arousals in sleeping children are associated with increased sympathetic discharge, as evidenced by attenuations in PAT signal. However, a significant proportion of PAT attenuations were not accompanied by visual electroencephalographic arousals. Thus, the importance of these autonomic arousals has yet to be explored in association with morbidities related to sleep-disordered breathing and, therefore, PAT technology cannot be recommended as an alternative tool for measuring arousals in children. Nevertheless, these data further support the contention that adult criteria for the measurement for arousals may not be adequate in children. 相似文献
96.
Mast TC Kigozi G Wabwire-Mangen F Black R Sewankambo N Serwadda D Gray R Wawer M Wu AW 《AIDS care》2004,16(1):81-94
To examine self-reported quality of life and health status of HIV-infected women and a comparison sample of HIV-uninfected women in rural Uganda, we culturally adapted a Lugandan version of the Medical Outcomes Survey-HIV (MOS-HIV). We administered a cross-sectional survey among 803 women (239 HIV-positive and 564 HIV-negative) enrolled in a community study to evaluate maternal and child health in Rakai District, Uganda. The interview took 20 minutes and was generally well-accepted. Reliability coefficients were >0.70, except for role functioning, energy and cognitive function. MOS-HIV scores for HIV-positive women were correlated with increasing number of physical symptoms and higher HIV viral load. Compared to HIV-negative women, HIV-positive women reported lower scores than HIV-negative women for general health perceptions, physical functioning, pain, energy, role functioning, social functioning, mental health and overall quality of life (p all <0.01). Substantial impairment was noted among women reporting >/=4 symptoms. In summary, HIV-positive women reported significantly poorer functioning and well-being than HIV-negative women. We conclude that patient-reported measures of health status and related concepts may provide a feasible, reliable and valid method to assess the impact of HIV/AIDS and future therapeutic interventions to improve patient outcomes in rural Africa. 相似文献
97.
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99.
Tissue factor pathway inhibitor (TFPI) abrogates coagulation initiated by the factor VIIa/tissue factor catalytic complex. While the gene structure of TFPI suggests that it is a secreted protein, a large pool of TFPI is associated with the vascular endothelium through its affinity for a glycosylphosphati-dylinositol (GPI)-linked membrane protein. Inhibition of tissue factor by TFPI coincides with the translocation of quaternary complexes containing tissue factor, factor VIIa, factor Xa, and TFPI to detergent-insoluble plasma membrane domains rich in cholesterol, sphingomyelin, and GPI-linked proteins known as lipid rafts and caveolae. It is not known if localization of TFPI to these membrane domains is required for its inhibition of tissue factor procoagulant activity. We generated chimeric TFPI molecules linked directly to the plasma membrane via a GPI anchor or hydrophobic transmembrane domain and expressed these in HEK293 cells that produce tissue factor but not endogenous TFPI. The GPI-anchored chimera was exclusively enriched in detergent-insoluble membrane fractions while the transmembrane molecule was not. Transfectants expressing equal levels of the GPI-linked or transmembrane TFPI displayed equal anticoagulant potency as assessed by tissue factor-mediated conversion of factor X to factor Xa. Disruption of lipid rafts with cyclodextrin likewise had no effect on the inhibitory activity of the transmembrane or GPI-linked TFPI chimeras in HEK293 cells, nor on endogenous TFPI expressed by ECV304 cells. Thus, we conclude that the GPI anchor and membrane localization to lipid rafts does not enhance inhibition of factor VIIa/tissue factor by cell-surface associated TFPI. 相似文献
100.
Mast BT Fitzgerald J Steinberg J MacNeill SE Lichtenberg PA 《The Clinical neuropsychologist》2001,15(2):196-202
Relatively little data exist concerning the utility of brief cognitive measures to detect dementia among African Americans. The current study evaluated the clinical utility of the Mini-Mental Status Exam (MMSE) and the Fuld Object Memory Evaluation (FOME) in detecting Alzheimer's disease (AD) among both African American and European American older adults. One hundred and forty geriatric patients from a large urban academic medical center were examined. Overall, the FOME appeared to be more effective in detecting AD than was the MMSE (93% sensitivity vs. 75% sensitivity, respectively), although both measures suffered from relatively low specificity (63.5) in the full sample. The FOME demonstrated exceptional clinical utility among African American patients (sensitivity 98.3%; specificity = 64.5; positive predictive power 83.8%; negative predictive power 95.2%). The results of this study support the use of the FOME among older African Americans to detect dementia. 相似文献