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31.
With the object to disclose an association between laryngeal papillomatosis and laryngeal carcinoma, we reviewed 102 patients with laryngeal papillomatosis treated between 1950 and 1979. Seven cases of laryngeal carcinomas were recorded and 1 patient with spread of papilloma to the bronchial tree developed a bronchial carcinoma. The time between onset of papilloma and diagnosis of carcinoma was 4-55 years (mean 24 years). For laryngeal carcinoma the ratio of observed to expected cases was 88. Of the 8 patients developing respiratory tract carcinoma, 2 had received treatment with radiation and 2 had been treated with Bleomycin. Four of these 8 patients were known smokers. This study shows that papillomatosis is more often associated with laryngeal carcinoma than previously reported. It appears, however, that laryngeal papillomas alone seldom induce carcinomas. Apart from irradiation and smoking, Bleomycin could be an important co-factor.  相似文献   
32.
Riding a motorcycle under the influence of alcohol is a dangerous activity, especially considering the high vulnerability of motorcyclists. The present research investigates the factors that affect the declared frequency of drink-riding among motorcyclists in Europe and explores regional differences. Data were collected from the SARTRE-4 (Social Attitudes to Road Traffic Risk in Europe) survey, which was conducted in 19 countries. A total sample of 4483 motorcyclists was interviewed by using a face-to-face questionnaire. The data were analyzed by means of multilevel ordered logit models. The results revealed significant regional differences (between Northern, Eastern and Southern European countries) in drink-riding frequencies in Europe. In general, declared drinking and riding were positively associated with gender (males), increased exposure, underestimation of risk, friends’ behaviour, past accidents and alcohol ticket experience. On the other hand, it was negatively associated with underestimation of the amount of alcohol allowed before driving, and support for more severe penalties.  相似文献   
33.
In this paper a unified methodology is presented for the modelling of the evolution of road safety in 30 European countries. For each country, annual data of the best available exposure indicator and of the number of fatalities were simultaneously analysed with the bivariate latent risk time series model. This model is based on the assumption that the amount of exposure and the number of fatalities are intrinsically related. It captures the dynamic evolution in the fatalities as the product of the dynamic evolution in two latent trends: the trend in the fatality risk and the trend in the exposure to that risk. Before applying the latent risk model to the different countries it was first investigated and tested whether the exposure indicator at hand and the fatalities in each country were in fact related at all. If they were, the latent risk model was applied to that country; if not, a univariate local linear trend model was applied to the fatalities series only, unless the latent risk time series model was found to yield better forecasts than the univariate local linear trend model. In either case, the temporal structure of the unobserved components of the optimal model was established, and structural breaks in the trends related to external events were identified and captured by adding intervention variables to the appropriate components of the model. As a final step, for each country the optimally modelled developments were projected into the future, thus yielding forecasts for the number of fatalities up to and including 2020.  相似文献   
34.
In this study, a sterile and biocompatible chitosan (CHI) gel for wound healing applications was formulated. CHI powder was treated in autoclave (ttCHI) to prepare sterile formulations. The heat treatment modified the CHI molecular weight, as evidenced by GPC analysis, and its physical–chemical features. Differential scanning calorimetry studies indicated that the macromolecules, before and after thermal treatment, differ in the strength of water-polymer interaction leading to different viscoelastic and flow properties. Thermally treated CHI exhibited the following effects: (i) increased the proliferation and migration of human foreskin foetal fibroblasts at 24 h; (ii) accelerated wound healing (measured as area of lesion) at 3 and 10 days in an in vivo model of pressure ulcers. These effects were linked to the increase of the hydroxyproline and haemoglobin content as well as Wnt protein expression. Moreover, we found a reduction of myeloperoxidase activity and TNF-α mRNA expression. These observations suggest the potential of this novel CHI gel in wound healing and other therapeutic applications.  相似文献   
35.
Water molecular dynamics during bread staling by Nuclear Magnetic Resonance   总被引:2,自引:0,他引:2  
Bread staling is a complex phenomenon that originates from multiple physico-chemical events (amylopectin retrogradation, water loss and redistribution) that are not yet completely elucidated. Molecular properties of white bread loaves were characterized by multiple proton Nuclear Magnetic Resonance (NMR) techniques (proton FID, T2 and T1 relaxation time) over 14 days of storage. Changes at a molecular level (faster decay of proton FIDs and shifting of proton T2 relaxation times distributions towards shorter times), indicating a proton mobility reduction of the bread matrix, were observed during storage. Multiple 1H T2 populations were observed and tentatively associated to water-gluten and water-starch domains. Proton T1 of bread was for the first time measured at variable frequencies (Fast Field Cycling NMR) and found to be strongly dependent upon frequency and to decrease in bread during storage, especially at frequencies ≤ 0.2 MHz. An additional proton T1 population, relaxing at 2 ms, was detected at 0.52 MHz only at early storage times and tentatively attributed to a water-gluten domain that lost mobility during storage.  相似文献   
36.
The aim of this project is the development of a noninvasive technique based on LED multispectral imaging (MSI) for monitoring the conservation state of the Dead Sea Scrolls (DSS) collection. It is well-known that changes in the parchment reflectance drive the transition of the scrolls from legible to illegible. Capitalizing on this fact, we will use spectral imaging to detect changes in the reflectance before they become visible to the human eye. The technique uses multivariate analysis and statistical process control theory. The present study was carried out on a "sample" parchment of calfskin. The monitoring of the surface of a commercial modern parchment aged consecutively for 2 h and 6 h at 80 °C and 50% relative humidity (ASTM) was performed at the Imaging Lab of the Library of Congress (Washington, DC, U.S.A.). MSI is here carried out in the vis-NIR range limited to 1 μm, with a number of bands of 13 and bandwidths that range from about 10 nm in UV to 40 nm in IR. Results showed that we could detect and locate changing pixels, on the basis of reflectance changes, after only a few "hours" of aging.  相似文献   
37.
Psychology's interest in religion and spirituality has greatly increased over the past few decades, and it has inspired the development of substantial scholarship in these areas. However, there continues to be a paucity of efforts to integrate this emerging scholarship into training programs. The author explores the historical and ideological context of psychotherapists' reluctance to address religious and spiritual issues in their academic programs and clinical practices. The article also offers seasoned psychotherapists concrete suggestions regarding how to enhance their religious and spiritual competencies with the aim of facilitating both the training of emerging psychotherapists and the treatment of religious and spiritual clients. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
38.
A method is presented for approximating fractional power averages of relaxation times for data equispaced in log time, without the need to invert multiexponential relaxation data. This form of average permits giving emphasis to short or long times depending on the choice of the p value, thus giving the possibility of representing different specific properties of porous media. This method has been tested on a large number of nuclear magnetic resonance (NMR) relaxation measurements in porous samples. This new algorithm appears to be robust with respect to both measurement and computation, and its major advantage is that it does not depend on a particular inversion method. Moreover, it permits a very fast computation.  相似文献   
39.
The arsenic removal capacity of a natural oxide sample consisting basically of Mn-minerals (birnessite, cryptomelane, todorokite), and Fe-oxides (goethite, hematite), collected in the Iron Quadrangle mineral province in Minas Gerais, Brazil, has been investigated. As-spiked tap water and an As-rich mining effluent with As-concentrations from 100 μg L−1 to 100 mg L−1 were used for the experiments. Sorbent fractions of different particle sizes (<38 μm to 0.5 mm), including spherical material (diameter 2 mm), have been used. Batch and column experiments (pH values of 3.0, 5.5, and 8.5 for batch, and about pH 7.0 for column) demonstrated the high adsorption capacity of the material, with the sorption of As(III) being higher than that of As(V). At pH 3.0, the maximum uptake for As(V) and for As(III)-treated materials were 8.5 and 14.7 mg g−1, respectively. The Mn-minerals promoted the oxidation of As(III) to As(V), for both sorbed and dissolved As-species. Column experiments with the cFeMn-c sample for an initial As-concentration of 100 μg L−1 demonstrated a very efficient elimination of As(III), since the drinking water limit of 10 μg L−1 was exceeded only after 7400 BV total throughput. The As-release from the loaded samples was below the limit established by the toxicity characteristic leaching procedure, thus making the spent material suitable for discharge in landfill deposits.  相似文献   
40.
With the progress of sequencing technologies, an ever-increasing number of variants of unknown functional and clinical significance (VUS) have been identified in both coding and non-coding regions of the main Breast Cancer (BC) predisposition genes. The aim of this study is to identify a mutational profile of coding and intron-exon junction regions of 12 moderate penetrance genes (ATM, BRIP1, CDH1, CHEK2, NBN, PALB2, PTEN, RAD50, RAD51C, RAD51D, STK11, TP53) in a cohort of 450 Italian patients with Hereditary Breast/Ovarian Cancer Syndrome, wild type for germline mutation in BRCA1/2 genes. The analysis was extended to 5′UTR and 3′UTR of all the genes listed above and to the BRCA1 and BRCA2 known regulatory regions in a subset of 120 patients. The screening was performed through NGS target resequencing on the Illumina platform MiSeq. 8.7% of the patients analyzed is carriers of class 5/4 coding variants in the ATM (3.6%), BRIP1 (1.6%), CHEK2 (1.8%), PALB2 (0.7%), RAD51C (0.4%), RAD51D (0.4%), and TP53 (0.2%) genes, while variants of uncertain pathological significance (VUSs)/class 3 were identified in 9.1% of the samples. In intron-exon junctions and in regulatory regions, variants were detected respectively in 5.1% and in 32.5% of the cases analyzed. The average age of disease onset of 44.4 in non-coding variant carriers is absolutely similar to the average age of disease onset in coding variant carriers for each proband’s group with the same cancer type. Furthermore, there is not a statistically significant difference in the proportion of cases with a tumor onset under age of 40 between the two groups, but the presence of multiple non-coding variants in the same patient may affect the aggressiveness of the tumor and it is worth underlining that 25% of patients with an aggressive tumor are carriers of a PTEN 3′UTR-variant. This data provides initial information on how important it might be to extend mutational screening to the regulatory regions in clinical practice.  相似文献   
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