The synthesis of polystyrene (PS) brushes on fully deuterated PS nanoparticles by surface‐initiated nitroxide‐mediated radical polymerization (SI‐NMRP) is reported. Due to the high demand of deuterated monomers, an efficient deuteration procedure of suitable and readily available precursors is developed. SI‐NMRP of styrene is improved regarding reaction control, grafting density, and conversion. Insights into the scaling behavior and conformational features of surface‐attached PS chains on deuterated particles are investigated by using dynamic light scattering measurements, proving that polymer brushes are formed. The particles with surface‐attached initiator are shown to be uniform spherical core‐shell particles by small‐angle neutron scattering measurements.
ObjectiveThe purpose of this study was to retrospectively evaluate the diagnostic accuracy and complications of CT-guided core needle biopsy (CT-guided CNB) of pleural lesion and the possible effects of influencing factors.ResultsDiagnostic accuracy, sensitivity, specificity, PPV, and NPV were 89.2%, 86.1%, 100%, 100%, and 67.8%, respectively. The influencing factors had no significant effect in altering diagnostic accuracy. As far as complications were concerned, occurrence of pneumothorax was observed in 14 (16%) out of 88 patients. Multivariate analysis revealed lesion size/pleural thickening as a significant risk factor (odds ratio [OR]: 8.744, p = 0.005) for occurrence of pneumothorax. Moreover, presence of pleural effusion was noted as a significant protective factor (OR: 0.171, p = 0.037) for pneumothorax.ConclusionCT-guided CNB of pleural lesion is a safe procedure with high diagnostic yield and low risk of significant complications. 相似文献
This study evaluated the effect of root canal disinfectants on the elimination of bacteria from the root canals, as well as their effect on glass-fiber posts bond strength.
Material and Methods
Fifty-three endodontically treated root canals had post spaces of 11 mm in length prepared and contaminated with E. faecalis. For CFU/ml analysis, eight teeth were contaminated for 1 h or 30 days (n=4). Teeth were decontaminated with 5% NaOCl, 2% CHX, or distilled water. As control, no decontamination was conducted. After decontamination, sterile paper points were used to collect samples, and CFU/ml were counted. For push-out, three groups were evaluated (n=15): irrigation with 2.5% NaOCl, 2% CHX, or sterile distilled water. A bonding agent was applied to root canal dentin, and a glass-fiber post was cemented with a dual-cured cement. After 24 h, 1-mm-thick slices of the middle portion of root canals were obtained and submitted to the push-out evaluation. Three specimens of each group were evaluated in scanning electron microscopy (SEM). Data were analyzed with one-way ANOVA and Dunnett’s T3 test (α=0.05).
Results
The number of CFU/ml increased from 1 h to 30 days of contamination in control and sterile distilled water groups. Decontamination with NaOCl was effective only when teeth were contaminated for 1 h. CHX was effective at both contamination times. NaOCl did not influence the bond strength (p>0.05). Higher values were observed with CHX (p<0.05). SEM showed formation of resin tags in all groups.
Conclusion
CHX showed better results for the irrigation of contaminated root canals both in reducing the bacterial contamination and in improving the glass-fiber post bonding. 相似文献
Reliable predictors of outcomes after treatment discontinuation in HBeAg‐negative chronic hepatitis B (CHB) patients have not been established. We investigated the role of hepatitis B surface antigen (HBsAg), interferon‐inducible protein‐10 (IP10) and hepatitis B core‐related antigen (HBcrAg) serum levels as predictors of HBsAg loss, relapse and retreatment in noncirrhotic HBeAg‐negative CHB patients who discontinued long‐term antiviral therapy. All HBsAg‐positive (n = 57) patients of the prospective DARING‐B study were included and followed monthly for 3 months, every 2/3 months until month‐12 and every 3/6 months thereafter. HBsAg, IP10 and HBcrAg levels were measured by enzyme immunoassays, and SCALE‐B score was calculated. Twelve patients achieved HBsAg loss before retreatment with 18‐month cumulative incidence of 25%. Independent predictors of HBsAg loss were baseline HBsAg and month‐1 IP10 levels. Of 10 patients with baseline HBsAg ≤100 IU/mL, 70% cleared HBsAg and 10% required retreatment. Of 23 patients with baseline HBsAg >1000 IU/mL, 4% cleared HBsAg and 43% required retreatment. Of 24 patients with intermediate baseline HBsAg (100‐1000 IU/mL), 17% cleared HBsAg and 21% required retreatment; in this subgroup, month‐1 IP10 was significantly associated with HBsAg loss, which occurred in 30% and 7% of cases with IP10 >150 and ≤150 pg/mL, respectively. Baseline HBcrAg was undetectable in all patients who cleared HBsAg and was associated with retreatment. SCALE‐B was associated with HBsAg loss but not with relapse or retreatment. In conclusion, HBsAg, IP10 and HBcrAg serum levels can be useful for the decisions and management of treatment discontinuation in noncirrhotic Caucasian patients with HBeAg‐negative CHB. 相似文献
The reaction of 2,6-diformyl-4-methylphenol (DFMF) with 1-amino-2-propanol (AP) and tris(hydroxymethyl)aminomethane (THMAM) was investigated in the presence of Cobalt(II) salts, (X = ClO4−, CH3CO2−, Cl−, NO3−), sodium azide (NaN3), and triethylamine (TEA). In one pot, the variation in Cobalt(II) salt results in the self-assembly of dinuclear, tetranuclear, and H-bonding-directed polynuclear coordination complexes of Cobalt(III), Cobalt(II), and mixed-valence CoIICoIII: [Co2III(H2L−1)2(AP−1)(N3)](ClO4)2 (1), [Co4(H2L−1)2(µ3-1,1,1-N3)2(µ-1,1-N3)2Cl2(CH3OH)2]·4CH3OH (2), [Co2IICo2III(HL−2)2(µ-CH3CO2)2(µ3-OH)2](NO3)2·2CH3CH2OH (3), and [Co2IICo2III (H2L12−)2(THMAM−1)2](NO3)4 (4). In 1, two cobalt(III) ions are connected via three single atom bridges; two from deprotonated ethanolic oxygen atoms in the side arms of the ligands and one from the1-amino-2-propanol moiety forming a dinuclear unit with a very short (2.5430(11) Å) Co-Co intermetallic separation with a coordination number of 7, a rare feature for cobalt(III). In 2, two cobalt(II) ions in a dinuclear unit are bridged through phenoxide O and μ3-1,1,1-N3 azido bridges, and the two dinuclear units are interconnected by two μ-1,1-N3 and two μ3-1,1,1-N3 azido bridges generating tetranuclear cationic [Co4(H2L−1)2(µ3-1,1,1-N3)2(µ-1,1-N3)2Cl2(CH3OH)2]2+ units with an incomplete double cubane core, which grow into polynuclear 1D-single chains along the a-axis through H-bonding. In 3, HL2− holds mixed-valent Co(II)/Co(III) ions in a dinuclear unit bridged via phenoxide O, μ-1,3-CH3CO2−, and μ3-OH− bridges, and the dinuclear units are interconnected through two deprotonated ethanolic O in the side arms of the ligands and two μ3-OH− bridges generating cationic tetranuclear [Co2IICo2III(HL−2)2(µ-CH3CO2)2(µ3-OH)2]2+ units with an incomplete double cubane core. In 4, H2L1−2 holds mixed-valent Co(II)/Co(III) ions in dinuclear units which dimerize through two ethanolic O (μ-RO−) in the side arms of the ligands and two ethanolic O (μ3-RO−) of THMAM bridges producing centrosymmetric cationic tetranuclear [Co2IICo2III (H2L1−2)2(THMAM−1)2]4+ units which grow into 2D-sheets along the bc-axis through a network of H-bonding. Bulk magnetization measurements on 2 demonstrate that the magnetic interactions are completely dominated by an overall ferromagnetic coupling occurring between Co(II) ions. 相似文献
