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1.

A key goal for implementation science is the identification of evidence-based consultation protocols and the active ingredients within these protocols that drive clinician behavior change. The current study examined clinicians’ self-coding of fidelity as a potential active ingredient of consultation for the Attachment and Biobehavioral Catch-up (ABC) intervention. It also examined two other potential predictors of clinician fidelity in response to consultation: dosage of consultation and working alliance. Twenty-nine clinicians (97% female, 62% White, M age?=?34 years) participated in a year of weekly fidelity-focused ABC consultation sessions, for which clinicians self-coded fidelity and received consultant feedback on both their coding and their fidelity. Data from the ABC fidelity measure were available for 1067 sessions coded by consultants, and clinicians’ self-coding accuracy was calculated from 1044 sessions coded by both clinicians and consultants. Alliance was measured with the Working Alliance Inventory—Trainee and Supervisor Versions. The study was observational, and fidelity and self-coding accuracy were modeled across time using hierarchical linear modeling. Clinicians’ ABC fidelity, as well as their self-coding accuracy, increased over the course of consultation. Clinicians’ self-coding accuracy predicted their initial fidelity and growth in fidelity. Working alliance was also linked to fidelity and self-coding accuracy. These results suggest that clinician self-coding should be further examined as an active ingredient of consultation. The study has important implications for the design of consultation procedures and fidelity assessments.

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CTLA-4 is required for the induction of high dose oral tolerance   总被引:5,自引:3,他引:5  
Mucosal and systemic administrations of high dose antigens induce long- lasting peripheral T cell tolerance. We and others have shown that high dose peripheral T cell tolerance is mediated by anergy or deletion and is preceded by T cell activation. Co-stimulatory molecules B7-1 (CD80)/B7-2 (CD86) and their counter-receptors CD28/CTLA-4 play pivotal roles in T cell activation and immune regulation. In the present study, we examined the roles of the B7 co-stimulation pathway in the generation of high dose peripheral T cell tolerance. We found that blocking B7:CD28/CTLA-4 interaction at the time of tolerance induction partially prevented T cell tolerance, whereas selective blockade of B7:CTLA-4 interaction completely abrogated peripheral T cell tolerance induced by either oral or i.p. antigens. These results suggest that CTLA-4-mediated feedback regulation plays a crucial role in the induction of high dose peripheral T cell tolerance.   相似文献   
4.
The correlation of coronary artery disease (CAD) with pro-oxidant/antioxidant balance and oxidative DNA damage was investigated.Seventy-seven patients with CAD and 44 healthy individuals as control were included in this study. The comparative ratios of ubiquinol-10/ubiquinone-10, 8-hydroxy-2''-deoxyguanosine/deoxyguanosine and the level of MDA measured by HPLC and the activities of GPX and SOD by colorimetric approach in blood samples obtained from patients with CAD were unraveled.8-OHdG/dG ratios, serum MDA level and GPX activity were found significantly elevated level in serum of CAD patients compared to control group. The SOD activity was observed in stable levels in CAD patients. Ubiquinol-10/ubiquinone-10 ratio was significantly lower in patients with CAD than the controls.The positive correlation was observed between 8-OHdG/dG ratios in both MDA levels and GPX activity, while the significant negative correlation was seemed between the ratio of 8-OHdG/dG and ubiquinol-10/ ubiquinone-10 as well as MDA levels and ubiquinol-10/ ubiquinone-10 ratio.We conclude that, both the disruption of pro-oxidant/antioxidant balance and oxidative stress in DNA may play an important role in the pathogenesis of coronary artery disease.  相似文献   
5.
Simon  SI; Rochon  YP; Lynam  EB; Smith  CW; Anderson  DC; Sklar  LA 《Blood》1993,82(4):1097-1106
We have recently found that antibodies to L-selectin, the homing receptor on neutrophils, are as effective as those to beta 2-integrin at blocking formyl peptide-stimulated aggregation. Therefore, we investigated the requirements for expression of L-selectin and beta 2- integrin on adjacent cells during aggregation. Fluorescence flow cytometry allowed characterization of aggregates on the basis of size and color, as well as antibody binding to these two adhesive molecules. Formyl peptide-stimulated aggregate formation was measured for individual populations fluorescently labeled red (LDS-751) or green (CD44-FITC), and interpopulation red-green cell conjugates. Blocking either the beta 2-integrin or L-selectin adhesive epitope with monoclonal antibody on individual cell populations resulted in an approximately 50% reduction in two-color aggregation as compared with that in unblocked samples. Shedding the L-selectin on a cell population by preincubation with complexes of lipopolysaccharide and its plasma membrane binding protein also decreased aggregation to a control population by approximately 50%. We examined the aggregation of neutrophils from patients genetically deficient in beta 2-integrin and clinically leukocyte adhesion deficient (LAD). LAD adhesion to normal neutrophils was dependent on the expression of L-selectin on LAD cells and beta 2-integrin on normal cells. Thus, the minimum requirement for adhesion between two mixed populations of neutrophils was that one population expressed the beta 2-integrin and the other expressed the L- selectin adhesive epitope.  相似文献   
6.
Influenza remains a major cause of illness and death in elderly people despite current vaccination programs. One factor is an immunization failure rate in the elderly that may be as high as 50%. To test whether administration of thymosin alpha 1 would result in greater antibody production, we administered it (900 micrograms/m2 subcutaneously twice weekly for eight doses) in conjunction with the 1986 trivalent influenza vaccine. Ninety men (65-99 years old, mean age 77.3 years) were randomized double-blind to receive thymosin alpha 1 or placebo by the same schedule; the sera from 85 of these men were acceptable for analysis. The two groups were similar with respect to underlying disease, medications, and age. No toxicity was observed in either group. Antibody response rate was defined as a four-fold rise in antibody titer over 3-6 weeks following vaccination and was measured by an enzyme-linked immunosorbent assay (ELISA). Analysis was performed on treatment groups and subgroups divided by the mean age: the older group consisted of subjects aged 77 years and older, and the younger group those aged from 65-76 years. Baseline and change in absolute antibody levels were compared by t test and using age as a continuous variable by multiple regression analysis.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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LaDuca  FM; Bettigole  RE; Bell  WR; Robson  EB 《Blood》1986,68(4):927-937
The contribution of von Willebrand factor (vWF)-platelet binding to platelet-collagen interaction was examined in vitro. The binding of vWF to platelets was mediated and regulated by ristocetin. Subthreshold concentrations of ristocetin (less than or equal to 1 mg/mL), insufficient to cause ristocetin-induced platelet aggregation (RIPA), were added to platelet-rich plasma (PRP) prior to the addition of collagen. The collagen-induced platelet aggregation (CIPA) was modified by ristocetin and the degree of alteration was dependent on the ristocetin concentration. Response as a function of ristocetin concentration was designated the Collagen-Platelet Aggregation Response (CoI-PAR). In normal PRP the CoI-PAR was a progressive inhibition followed by decreasing inhibition and then an enhanced response. The enhanced response occurred over a narrow range of ristocetin concentrations (0.8 to 1.0 mg/mL). In the absence of vWF (severe von Willebrand's disease, Type I, vWF less than 1%) the CoI-PAR was a progressive, eventually complete inhibition with no enhanced response (with ristocetin concentrations up to 3.0 mg/mL). With addition of vWF to this PRP an enhanced response was observed at a ristocetin concentration inversely proportional to the vWF level. PRP from a patient with severe Hemophilia A showed a response within the normal range. Subthreshold ristocetin did not cause plasma protein precipitation or platelet release of 3H-serotonin, nor induce micro platelet aggregate formation. Digestion of platelet membrane glycoproteins (GP(s] with chymotrypsin demonstrated that upon removal of GPI, RIPA was absent, CIPA retained and the CoI-PAR was progressive inhibition, with no enhancement. With removal of GPs I, II, and III, RIPA, CIPA, and the CoI-PAR were absent. A dose-response 125I-vWF- platelet binding occurred with increasing ristocetin concentrations which was unchanged by the addition of collagen. These results demonstrated that ristocetin-platelet association inhibited CIPA, and vWF-platelet binding enhanced platelet-collagen adhesion and platelet aggregation. The in vitro-enhanced CIPA represents a vWF-dependent aggregation of sufficient magnitude to overcome the inhibitory effect of ristocetin. These studies demonstrate an influential interaction of ristocetin, vWF, and collagen with the platelet membrane and imply an important hemostatic contribution of vWF-platelet binding in platelet- collagen interaction.  相似文献   
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10.
Effect of carvedilol on survival in severe chronic heart failure   总被引:168,自引:0,他引:168  
BACKGROUND: Beta-blocking agents reduce the risk of hospitalization and death in patients with mild-to-moderate heart failure, but little is known about their effects in severe heart failure. METHODS: We evaluated 2289 patients who had symptoms of heart failure at rest or on minimal exertion, who were clinically euvolemic, and who had an ejection fraction of less than 25 percent. In a double-blind fashion, we randomly assigned 1133 patients to placebo and 1156 patients to treatment with carvedilol for a mean period of 10.4 months, during which standard therapy for heart failure was continued. Patients who required intensive care, had marked fluid retention, or were receiving intravenous vasodilators or positive inotropic drugs were excluded. RESULTS: There were 190 deaths in the placebo group and 130 deaths in the carvedilol group. This difference reflected a 35 percent decrease in the risk of death with carvedilol (95 percent confidence interval, 19 to 48 percent; P=0.00013, unadjusted; P=0.0014, adjusted for interim analyses). A total of 507 patients died or were hospitalized in the placebo group, as compared with 425 in the carvedilol group. This difference reflected a 24 percent decrease in the combined risk of death or hospitalization with carvedilol (95 percent confidence interval, 13 to 33 percent; P<0.001). The favorable effects on both end points were seen consistently in all the subgroups we examined, including patients with a history of recent or recurrent cardiac decompensation. Fewer patients in the carvedilol group than in the placebo group withdrew because of adverse effects or for other reasons (P=0.02). CONCLUSIONS: The previously reported benefits of carvedilol with regard to morbidity and mortality in patients with mild-to-moderate heart failure were also apparent in the patients with severe heart failure who were evaluated in this trial.  相似文献   
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