1,557 research outputs found

    The Association of Thyrotropin and Autoimmune Thyroid Disease in Developing Papillary Thyroid Cancer

    Get PDF
    Background. Papillary thyroid carcinoma (PTC) is the most common type of malignant thyroid neoplasm. However, the incidence of PTC with autoimmune thyroid disease (AITD) varies between studies. This study aims to investigate whether patients with AITD have increased incidence of PTC. We also analyzed the relationship of serum thyroid-stimulating hormone (TSH) levels and PTC in relation to AITD based on histopathological data. Methods. A total of 533 participants who underwent thyroidectomy were enrolled in this retrospective study based on clinicohistopathological data and known thyroid autoantibodies. Patients were divided into PTC and benign groups according to histopathologic diagnosis. Age, gender, body mass index, and serum TSH level before thyroidectomy were recorded. Results. Of the 533 enrolled patients, 159 (29.8%) were diagnosed with PTC, of which 38 (35.5%) had Hashimoto’s thyroiditis (HT). More patients with HT were female, and patients with HT, Graves’ disease, and thyroid nodules with higher TSH level had a higher incidence of PTC. Conclusions. A high proportion of the patients with PTC had HT. There was a trend that a higher serum TSH level was associated with a greater risk of thyroid cancer

    Electronic band structures of Ge1−xSnx semiconductors: A first-principles density functional theory study

    Get PDF
    [[abstract]]We conduct first-principles total-energy density functional calculations to study the band structures in Ge 1− x Sn x infrared semiconductor alloys. The norm-conserving optimized pseudopotentials of Ge and Sn have been constructed for electronic structure calculations. The composition-bandgap relationships in Ge 1−x Sn x lattices are evaluated by a detailed comparison of structural models and their electronic band structures. The critical Sn composition related to the transition from indirect- to direct-gap in Ge 1−x Sn x alloys is estimated to be as low as x∼ 0.016 determined from the parametric fit. Our results show that the crossover Sn concentration occurs at a lower critical Sn concentration than the values predicted from the absorption measurements. However, early results indicate that the reliability of the critical Sn concentration from such measurements is hard to establish, since the indirect gap absorption is much weaker than the direct gap absorption. We find that the direct band gap decreases exponentially with the Sn composition over the range 0 0.375, in very good agreement with the theoretical observed behavior [D. W. Jenkins and J. D. Dow, Phys. Rev. B 36, 7994, 1987]. For homonuclear and heteronuclear complexes of Ge 1−x Sn x alloys, the indirect band gap at L-pointis is found to decrease homonuclear Ge-Ge bonds or increase homonuclear Sn-Sn bonds as a result of the reduced L valley. All findings agree with previously reported experimental and theoretical results. The analysis suggests that the top of valence band exhibits the localization of bond charge and the bottom of the conduction band is composed of the Ge 4s4p and/or Sn 5s5p atomic orbits.[[booktype]]紙本[[booktype]]電子

    Risk factors and clinical significance of bacteremia caused by Pseudomonas aeruginosa resistant only to carbapenems

    Get PDF
    Background/purposeCarbapenem-resistant Pseudomonas aeruginosa infections have been a challenge and issue in hospital settings. However, the clinical impact of P. aeruginosa blood isolates resistant only to carbapenems has never been discussed previously.MethodsTo assess the risk factors and clinical significance of bacteremia caused by carbapenem resistance only P. aeruginosa (CROPA), a 6-year retrospective case–control study was conducted. The CROPA strains were defined as isolates susceptible to ciprofloxacin, antipseudomonal penicillins and cephalosporins, and aminoglycosides but resistant to one antipseudomonal carbapenem (imipenem or meropenem) or both. The controls were selected among patients with bacteremia due to P. aeruginosa susceptible to all above classes of antipseudomonal antibiotics, which was defined as all-susceptible P. aeruginosa.ResultsTwenty-five patients had at least one blood culture positive for CROPA, and 50 controls had all-susceptible P. aeruginosa bacteremia. CROPA bacteremia had a high 30-day mortality rate (72.0%), as compared to 26.0% for the controls (p < 0.001). Through multivariate analysis, carbapenem exposure was the only risk factor for developing CROPA bacteremia (p = 0.002). A comparison between the surviving and deceased patients with CROPA bacteremia showed that nine (50%) of those who died, but none of the survivors, received carbapenems as the initial empirical therapy (p = 0.027).ConclusionCarbapenem exposure was associated with emergence of CROPA infections. Repeated carbapenem use in such patients might increase rates of inappropriate initial empirical treatment and mortality. Prudent carbapenem use is important to reduce the emergence of CROPA

    First measurement of anti-kT_\mathrm{T} jet spectra and jet substructure using the archived ALEPH e+ee^+e^- data at 91.2 GeV

    Full text link
    We present the first anti-kT_{T} jet spectrum and substructure measurements using the archived ALEPH e+ee^+e^- data taken in 1994 at a center of mass energy of s=91.2\sqrt{s} = 91.2 GeV. Jets are reconstructed with the anti-kT_{T} algorithm with a resolution parameter of 0.4. It is the cleanest test of jets and QCD without the complication of hadronic initial states. The fixed center-of-mass energy also allows the first direct test of pQCD calculation. We present both the inclusive jet energy spectrum and the leading dijet energy spectra, together with a number of substructure observables. They are compared to predictions from PYTHIA6, PYTHIA8, Sherpa, HERWIG, VINCIA, and PYQUEN. None of the models fully reproduce the data. The data are also compared to two perturbative QCD calculations at NLO and with NLL'+R resummation. The results can also serve as reference measurements to compare to results from hadronic colliders. Future directions, including testing jet clustering algorithms designed for future electron-ion collider experiments, will also be discussed

    Enterovirus 71 Maternal Antibodies in Infants, Taiwan

    Get PDF
    Enterovirus 71 (EV71) causes life-threatening disease outbreaks in young children in Asia. This cohort study was conducted to understand the dynamics of maternal EV71 antibodies in Taiwanese young infants. Approximately 50% of neonates had detectable EV71 neutralizing antibodies, which declined to almost undetectable levels by 6 months of age
    corecore