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41.
Immunogenicity of fowlpox virus expressing the avian influenza virus H5 gene (TROVAC AIV-H5) in cats 总被引:4,自引:0,他引:4
Karaca K Swayne DE Grosenbaugh D Bublot M Robles A Spackman E Nordgren R 《Clinical and diagnostic laboratory immunology》2005,12(11):1340-1342
Vaccination of cats with fowlpox virus expressing the avian influenza (AI) virus H5 hemagglutinin gene (TROVAC AI) resulted in detectable hemagglutination inhibition (HI) antibody responses to the homologous A/Turkey/Ireland/1378/83 (H5N8) (A/tky/Ire/83) AI virus antigen. The HI antibody responses to heterologous A/Chicken/Indonesia/7/03 (H5N1) (A/ck/Indonesia/03) AI virus antigen were also detected in all vaccinated cats, but only after booster vaccinations. The vaccine described in this study and other poxvirus-vectored vaccines may be of value for the prophylaxis of AI virus-associated morbidity and mortality in mammals. 相似文献
42.
Polydactyly may be preaxial or tibial (hallux-side), postaxial or ulnar (side of the little toe) and central (middle toes). The duplication may appear at the distal and medial phalanges or at the whole digit. The metatarsal bone may be part wise or completely duplicated, the accessory toes may share only one metatarsal. Surgical intervention may be indicated in shoe problems, for esthetic reasons or, especially in duplication of the metatarsales, because of secondary deviation of the toes and therefore shoe problems or plantar callosities. Preoperative analysis including x-ray is of great importance to achieve good functional and cosmetic results. 相似文献
43.
We have previously shown that exposure of mice to 2,3,7, 8-tetrachlorodibenzo-p-dioxin (TCDD) induces activation-like changes in splenic dendritic cells (DC) in the absence of antigen challenge. Since activation of DC reduces their ability to phagocytize antigen, we examined the effects of TCDD on the ability of DC to process and present antigen to antigen-specific T cells and to internalize latex beads. Additionally, the expression of costimulatory and adhesion molecules was examined on DC from TCDD-treated mice injected with allogeneic tumor cells. The ability of DC from C57Bl/6 mice to induce proliferation of keyhole limpet hemocyanin (KLH)-specific 10.5.17 T cells and production of IL-4 was not significantly altered by TCDD exposure, either when KLH was added in vitro or when the mice were injected with KLH prior to DC isolation. In contrast, ovalbumin (OVA) presentation by DC from TCDD-treated Balb/c mice induced enhanced proliferation of OVA-specific D011.10 T cells, although the production of IL-2 and IFN-gamma was not affected. Enhanced in vivo proliferation of adoptively transferred, CFSE-labeled DO11.10 T cells was also observed in TCDD-treated Balb/c mice that were challenged with OVA. TCDD treatment modulated the expression of major histocompatibility complex (MHC) class II, CD24, ICAM-1, CD40, and LFA-1 on splenic DC from C57Bl/6 mice injected with allogeneic tumor cells; however, the effects of TCDD were identical to changes seen previously in nonimmune mice, suggesting that these effects were not antigen-dependent. Finally, TCDD treatment did not affect the ability of splenic DC to internalize latex beads administered in vivo. Taken together, these results suggest that the activation-like changes induced in DC by TCDD do not suppress the ability of DC to process and present antigen, but may enhance their ability to provide activation signals to T cells. This, in turn, may alter the survival of the T cells, the DC, or both, and might lead to dysregulation of the immune response. 相似文献
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Peter Franks Erica I Lubetkin Marthe R Gold Daniel J Tancredi Haomiao Jia 《Medical decision making》2004,24(3):247-254
BACKGROUND: Preference scores for the Medical Outcomes Study (MOS) SF-12 would enable its use in cost-effectiveness analyses. Previous mapping studies of MOS instruments top reference-based instruments have not examined performance in national samples. PARTICIPANTS: 15,000 adults in the 2000 Medical Expenditure Panel Survey annual survey including the SF-12 and EQ-5D Index. METHODS: Regression of the EQ-5D Index scores onto the physical and mental component summary scores of the SF-12, testing 2nd-4th degree polynomial and spline models, including and excluding sociodemographics. RESULTS: A 2nd degree polynomial model explained 63% of the variance in EQ-5D scores, with robust internal and external validation. More complex mod-els explained minimally additional variance. Compared with EQ-5D valuations, prediction models overestimated the lowest health states (6% of the population). CONCLUSIONS: The mapped SF-12 yields usable preference-scaled scores, with some caution for the lowest health states. 相似文献
47.
OBJECTIVES: Although the EQ-5D has been used with increasing frequency to measure health-related quality of life, to date, the measure's validity has not been examined in Chinese American immigrants. We evaluated the construct validity of the EQ-5D by testing its performance with respect to sociodemographic and clinical characteristics of the population and comparing responses on the EQ dimensions with the SF-36 subscales. METHODS: The study surveyed low-income Chinese patients attending a community health center in New York City's Chinatown. Participants received self-administered versions of the EQ-5D and SF-36 and additional questions regarding demographic and clinical information. RESULTS: 856 patients were approached and data were collected from 523 patients (61%). Analysis of the EQ-5D responses by sociodemographic and clinical variables found significant differences among categories of age, gender, marital status, number of medical problems, self-rated health, and specific medical problems. Correlations between similar dimensions and subscale scores were stronger between the two measures than dissimilar ones. Patients without impairments on a given EQ dimension tended to have higher SF-36 subscale scores than patients reporting 'any' impairment (i.e. some/moderate or severe). CONCLUSIONS: The results provide initial support for the construct validity of the EQ-5D in our sample. Further studies should compare the performance of the EQ-5D with other preference-based measures in Chinese persons and examine the valuations that both low-income and Chinese persons place on core aspects of health. 相似文献
48.
Tovi Lehmann Douglas H Graham Erica R Dahl Lilian M G Bahia-Oliveira S M Gennari J P Dubey 《Infection, genetics and evolution》2004,4(2):107-114
Previous studies of Toxoplasma gondii, based on samples dominated by clinical isolates, have concluded that its population structure is clonal, despite the sexual reproduction that occurs in cats. To determine whether this applies to non-clinical isolates, we compared patterns of linkage disequilibrium (LD) among seven loci in samples of T. gondii from Brazil and the US. LD was detected in both locations, but it was substantially lower in Brazil. The lower LD in Brazil can be explained by a higher rate of sexual reproduction between different genotypes (outcrossing) because of a higher rate of transmission. The extent of LD between pairs of physically unlinked loci varied significantly in each location. Moreover, the magnitude of LD between corresponding locus pairs in Brazil and the US was correlated, despite minimal gene exchange between the continents (mean FST = 0.19). The heterogeneity among locus pairs and the correlation in LD between physically unlinked locus pairs from different continents suggests that locus-specific factors, such as epistatic selection are involved in maintaining LD in T. gondii. Possibly, the unique life cycle of T. gondii with its unpredictable transmission among diverse host species and distinct ecological habitats requires specific combinations of alleles from multiple loci. The usefulness of typing isolates based on physically unlinked loci is questioned not only by the geographic variation in the reproductive population structure, but mainly by the low overall predictability of the genotype of one locus based on the genotype in another (unlinked) locus. This predictability ranged between 23 and 45%, but was close to nil for a considerable fraction of locus pairs. 相似文献
49.
Randomized placebo-controlled study of low-dose warfarin for the prevention of central venous catheter-associated thrombosis in patients with cancer. 总被引:13,自引:0,他引:13
Stephen Couban Michael Goodyear Margot Burnell Sean Dolan Parveen Wasi David Barnes Darlene Macleod Erica Burton Pantelis Andreou David R Anderson 《Journal of clinical oncology》2005,23(18):4063-4069
PURPOSE: In this multicenter, randomized, placebo-controlled clinical trial, we studied whether warfarin 1 mg daily reduces the incidence of symptomatic central venous catheter (CVC) -associated thrombosis in patients with cancer. PATIENTS AND METHODS: Two hundred fifty-five patients with cancer who required a CVC for at least 7 days were randomly assigned to receive warfarin 1 mg or placebo. RESULTS: There were 11 (4.3%) symptomatic CVC-associated thromboses among 255 patients, with no difference in the incidence of symptomatic CVC-associated thrombosis between patients taking warfarin 1 mg daily (six of 130 patients; 4.6%) and patients taking placebo (five of 125 patients; 4.0%; hazard ratio, 1.20; 95% CI, 0.37 to 3.94). Warfarin had no effect on CVC life span (84 days v 63 days in control and warfarin groups, respectively; 95% confidence limit, -16 to 55 days; P = .09), and it did not affect the number of premature CVC removals (23.2% v 25.4% in control and warfarin groups, respectively; 95% confidence limit of difference -8.34 to 12.71; P = .68) or the frequency of major bleeding episodes (2% v 0% in control and warfarin groups, respectively; P = .5, Fisher's exact test). CONCLUSION: Symptomatic CVC-associated thrombosis in patients with cancer, although significant, is less common than previously reported. In this study, the administration of warfarin 1 mg daily did not reduce the incidence of symptomatic CVC-associated thrombosis in patients with cancer. However, the low rate of symptomatic CVC-associated thrombosis means that a much larger trial is required to address this issue definitively. 相似文献