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We report 28 German patients with contact granuloma (27 male, 1 female). Their mean age was 52 years (ranging from 35 to 70). Thirty-two percent were retired. The occupations of the others represented a wide range of different jobs. The majority of the sample had a middle educational level. Most patients lived with their family or with a partner. According to self-assessments, 68% had average daily strain on their speaking voice. All patients were nonsmokers. The patients felt themselves more disturbed by somatic troubles as the general population. Heartburn was felt by nearly half of the patients. A little more than half of the patients suffered from globus sensation. Thus, it is not possible at present to explain the laryngeal contact granuloma by sociodemographic data, vocal stress, or special somatic complaints in this sample. Therefore a multifactorial etiology should be supposed. 相似文献
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Christiane A. Helm 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》1994,106(14):1591-1591
148.
The synthesis and crystal structure of Cs3Mn[Nb6Cl9O3(CN)6]0.6H2O are described in this work. It crystallizes in the cubic system (space group Fm-3m; a=15.708(5) Å) and is characterized by a static orientational disorder of the [Nb6Cl9O3(CN)6]5− cluster units. It results in a framework structurally related to that encountered in the well known Prussian Blue family prepared for different hexacyanometallates. The charge of the framework is compensated by cesium cations that are located in the tetrahedral cavities of the c.f.c. lattice of units along with water molecules. We will evidence the features that act in the crystallization of solid state compounds built up from ordered or disordered units as well as the influence of orientational disorder on interatomic distances obtained from single-crystal X-ray diffraction investigations. 相似文献
149.
Henry Delince Christiane Soika Pter Horvatovich Gerhard Rechkemmer Eric Marchioni 《Radiation Physics and Chemistry》2002,63(3-6):431-435
Previous experiments had indicated a slight genotoxic potential both in rat and in human colon cells of a sample of 2-dodecylcyclobutanone, a compound formed by irradiation of food containing palmitic acid in its triglycerides. Up to date, there is no evidence that 2-alkylcyclobutanones occur in non-irradiated foodstuffs, consequently it is prudent to test several members of the class of 2-alkylcyclobutanones which are produced by treatment of fat-containing food with ionising radiation. In this work, 2-tetradecylcyclobutanone (derived from stearic acid) has been tested for its cytotoxic and genotoxic potential. Human colon tumor cell lines, i.e. HT 29 and HT 29 clone 19A, were employed as models for in vitro experiments for cytotoxicity and genotoxicity tests. Cytotoxicity was measured by tetrazolium salt reduction assays (MTT and WST-1) and genotoxicity by determining DNA damage using the Comet Assay. Neither cytotoxic nor genotoxic effects were induced by 2-TCB in HT 29 or HT 29 cl 19A cells at an incubation time of 30 min at 37°C, not even at the highest concentration (400 μM) tested. After prolonged incubation times (1–2 days) at higher concentrations (>50 μM) cytotoxicity did, however, appear. Studies on other 2-alkylcyclobutanones are in progress. 相似文献
150.
Onjia AE Milonjić SK Todorović M Loos-Neskovic C Fedoroff M Jones DJ 《Journal of colloid and interface science》2002,251(1):10-17
The surface properties of Ni and Cu hexacyanoferrates were investigated by the inverse gas chromatography method. Retentions of 10 organic compounds were measured at zero surface coverage in the temperature range 80 to 95 degrees C. The gas/solid partition coefficients and the related thermodynamic data of adsorption (standard free energy change, standard state enthalpies, and entropy changes) also at zero surface coverage were determined. The dispersive component of free surface energy of both hexacyanoferrates, at investigated temperatures, was calculated. The surface acid/base properties were also evaluated using polar adsorbates and the results obtained indicate that nickel hexacyanoferrate is more acidic than copper hexacyanoferrate. 相似文献