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61.
CONTEXT: One or both commercial tuberculin skin test reagents (Aplisol and Tubersol) may have a high rate of false-positive reactions. OBJECTIVE: To compare the reaction size and specificity of skin testing with Aplisol, Tubersol, and the standard purified protein derivative (PPD-S1). DESIGN: Double-blind trial, conducted between May 14, 1997, and October28, 1997, in which each individual received 4 tuberculin skin reagents at sites assigned at random. SETTING: Health departments and universities in 6 US cities. PARTICIPANTS: A total of 1555 persons at low risk of latent tuberculosis infection. INTERVENTION: Simultaneous skin tests with Aplisol, Tubersol, PPD-S1, and either a second PPD-S1 or PPD-S2 (a proposed new standard). MAIN OUTCOME MEASURE: Reaction size at each injection site measured by 2 investigators blinded to type of reagent. RESULTS: Aplisol produced slightly larger reactions than Tubersol, but this difference did not significantly change skin test interpretation. The mean +/- SD reaction sizes were 3.4+/-4.2 mm with Aplisol, 2.1+/-3.2 mm with Tubersol, and 2.5+/-3.6 mm with PPD-S1. Assuming that all participants were uninfected and using a 10-mm cutoff, the specificities of the tests were high: Aplisol, 98.2%; Tubersol, 99.2%; and PPD-S1, 98.9%. Significant variability was not detected in interobserver, host, and lot-to-lot reagent comparisons. CONCLUSION: Using a cutoff of at least 10 mm, testing with 3 different PPD reagents resulted in similar numbers of uninfected persons being correctly classified. 相似文献
62.
CY Spong SJ Lee SK McCune G Gibney DT Abebe R Alvero DE Brenneman JM Hill 《Canadian Metallurgical Quarterly》1999,140(2):917-924
Vasoactive intestinal peptide (VIP) is an important growth regulator of the embryonic day (E)9-E11 mouse. In comparably aged rat embryos, VIP messenger RNA (mRNA) is not detectable; however, peak concentrations of VIP in maternal rat serum indicate a nonembryonic source. In the current study, mouse maternal and embryonic tissues were examined from E6-E12. Although RT-PCR revealed VIP mRNA in E6-E7 conceptuses, by E8 (when extraembryonic tissues could be separated from the embryo), VIP mRNA was detected only in the decidua/trophoblast. Decidual/trophoblastic VIP mRNA decreased until E10, after which it was not detectable. VIP mRNA was not apparent in the embryo until E11-E12. At E9, VIP immunoreactivity was localized to abundant, diffuse cells in the decidua basalis, which were also immunoreactive for T cell markers. VIP binding sites were dense in the decidua/trophoblast at E6, but gradually decreased until E10, after which they were not apparent. VIP binding sites were detected in embryonic neuroepithelium by E9. The transient presence of VIP binding sites and mRNA in the decidua/trophoblast correlate with the critical period of VIP growth regulation, when VIP mRNA is absent in the embryo. These findings suggest that maternal lymphocytes are the source of VIP's regulating early postimplantation embryonic growth. 相似文献
63.
64.
AbstractInteractions in mixtures of gelatin and sodium casemate have been studied over a range of pH. Phase separation in these mixtures has been examined using electrophoresis to identify protein components involved in complex formation. Rheological properties and functional properties of compatible mixtures have been evaluated. Mixtures of 1 % acid-processed gelatin and 1 % caseinatc were found to interact at pH 5.5 to form a separate complex coacervale phase. At lower pH levels, the caseinate component formed aggregates but did not precipitate in the presence of gelatin. These complex systems had increased gel strength compared with gelatin alone and produced low-melting gels of reduced elasticity. Further synergistic increases in gel strength were observed in the presence of 10% maltodextrin.. 相似文献
65.
Eui‐Cheol Shin Ronald B. Pegg R. Dixon Phillips Ronald R. Eitenmiller 《European Journal of Lipid Science and Technology》2010,112(2):195-207
Though peanuts are classified as a high‐fat food, they possess good proportions of fatty acids deemed as heart healthy. The fatty acid compositions of Runner peanuts were determined for commercially grown cultivars over two recent crop years. GC‐FID analyses revealed that the fatty acid levels for Runner peanuts were significantly (p <0.05) different among the normal, mid‐, and high‐oleic peanuts investigated. Oleic acid‐to‐linoleic acid (O/L) ratios were found to be 1.93 ± 0.30, 5.25 ± 1.12, and 16.9 ± 5.20 for normal, mid‐, and high‐oleic peanut lipids, respectively. Tamrun OL01 possessed a fatty acid profile characteristic of a mid‐oleic cultivar. From the sample set (n = 151), mean % weights for oleic acid and linoleic acid were 52.09 ± 2.84 and 27.38 ± 2.60 in normal, 69.33 ± 3.18 and 13.66 ± 2.35 in mid‐oleic, and 78.45 ± 2.05 and 5.11 ± 1.67 in high‐oleic peanuts, respectively. Cluster analysis segregated cultivars based on fatty acids into normal, mid‐, and high‐oleic groups. Factorial analysis revealed that cultivar effects were significant (p <0.01) for all fatty acids, except for lignoceric acid. Cultivar effects were also highly significant (p <0.001) for O/L, IV, unsaturated/saturated fatty acid (U/S) ratio, and % saturation. Significant crop year effects were shown for palmitic, oleic, arachidic, gondoic, and lignoceric acids, as well as U/S ratio and % saturation. Healthy unsaturated fats accounted for ?80% in all crop years and cultivars. 相似文献
66.
Heterodimers of the 70 and 80 kDa Ku autoantigens (Ku70 and Ku80) activate the DNA-dependent protein kinase (DNA-PK). Mutations in any of the three subunits of this protein kinase (Ku70, Ku80 and DNA-PKcs) lead to sensitivity to ionizing radiation (IR) and to DNA double-strand breaks, and V(D)J recombination product formation defects. Here we show that the IR repair, DNA end binding and DNA-PK defects in Ku70-/- embryonic stem cells can be counteracted by introducing epitope-tagged wild-type Ku70 cDNA. Truncations and chimeras of Ku70 were used to identify the regions necessary for DNA end binding and IR repair. Site-specific mutational analysis revealed a core region of Ku70 responsible for DNA end binding and heterodimerization. The propensity for Ku70 to associate with Ku80 and to bind DNA correlates with the ability to activate DNA-PK, although two mutants showed that the roles of Ku70 in DNA-PK activation and IR repair are separate. Mutation of DNA-PK autophosphorylation sites and other structural motifs in Ku70 showed that these sites are not necessary for IR repair in vivo. These studies reveal Ku70 features required for double-strand break repair. 相似文献
67.
T Walkow A Liekfeld N Anders DT Pham C Hartmann J Wollensak 《Canadian Metallurgical Quarterly》1997,104(9):1380-1386
OBJECTIVE: To evaluate prospectively a diffractive (811E, Pharmacia; power add +4.0 D) versus a refractive (PA154N, Allergan; power add +3.5 D) designed multifocal lens. PARTICIPANTS: Eighty patients planned for cataract surgery without additional ocular pathologies were randomized into the diffractive or refractive group, respectively. INTERVENTION: A standardized no-stitch phacoemulsification with implantation of one of the two multifocal lenses was performed in each patient. MAIN OUTCOME MEASURES: Distance and near-visual acuity, contrast sensitivity, low contrast visual acuity, glare visual acuity, and depth of focus were measured after surgery. RESULTS: All treated patients had best-corrected visual acuities of 20/30 or better. Near-uncorrected vision was significantly better (P < 0.0001) with the diffractive lens (mean, J1) than with the refractive lens (mean, J4). Low contrast visual acuity (61 +/- 12% versus 59 +/- 9%), glare visual acuity (39 +/- 19% versus 38 +/- 14%), and contrast sensitivity (1.48 +/- 0.08 versus 1.50 +/- 0.12) were not significantly different between the groups. CONCLUSIONS: Both lens designs showed satisfactory functional results with advantages for the diffractive lens design. 相似文献
68.
69.
L Clarke DS Buss DT Juniper MA Lomax ME Symonds 《Canadian Metallurgical Quarterly》1997,82(6):1015-1027
This study examines the precise time course that brown adipose tissue (BAT) takes to adopt the characteristics of white adipose tissue in postnatal lambs. Perirenal adipose tissue was sampled from ewe-reared lambs within 1 h of birth and at 1, 2, 4, 7, 14, 21 and 30 days of age and analysed for the amount of mRNA for uncoupling protein (UCP), the amount and activity of UCP, and protein, mitochondrial protein and lipid content. This was combined with measurements of colonic temperature and jugular venous plasma concentrations of thyroid hormones and insulin-like growth factor-1 (IGF-1). Over the first 4-7 days of age, large quantities of UCP mRNA were associated with a peak in plasma triiodothyronine concentration at 2 days of age followed by a maximal amount and activity of UCP at 4 days and a basal colonic temperature of 39.3 degrees C. Between 7 and 30 days there was a large increase in lipid deposition as the amount and activity of UCP and the amount of UCP mRNA declined to basal values and colonic temperature was maintained at 40 degrees C. A significant positive relationship between perirenal adipose tissue lipid content and plasma IGF-1 concentration was observed throughout the study period. It is concluded that ovine adipose tissue maturation occurs in two distinct phases over the first month of life. The precise time scale of this process could be regulated in part by the lamb's body temperature which determines whether adipose tissue is required for heat production (i.e. BAT) or as an endogenous energy source (i.e. white adipose tissue). 相似文献
70.
Artefacts in images of electrical current distribution measured by magnetic resonance imaging (MRI) are presented. These artefacts, caused by the effects of the connecting cables used to apply the electrical current to the object during the MRI scan, can lead to an underestimation of the magnitude of the electrical current measured in the experiment. The size of this underestimate depends upon the experimental geometry, but in the experiments and simulations described here, performed with a cylindrical phantom approximately 8 cm long and 8 cm in diameter, the difference can be 27%. These artefacts are reduced if the connecting cables are rigidly fixed to the object so that the induced magnetic field is correctly measured during the MRI experiment. 相似文献