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941.
Marina Hara Hidenobu Matsuzaki Naoki Katase Teruhisa Unetsubo Yoshinobu Yanagi Hitoshi Nagatsuka Jun-ichi Asaumi 《Oral Radiology》2014,30(1):105-110
We previously reported that dynamic contrast-enhanced MRI parameters and time–signal intensity curves (TICs; also known as contrast index curves) are useful for the differential diagnosis of jawbone lesions. In particular, odontogenic fibroma and ossifying fibroma, which possess similar histopathological features (i.e., a mixture of hard and soft tissue components), display unique TIC patterns, and we consider that the TIC patterns of these lesions reflect their hard and soft tissue components. Therefore, fibrous dysplasia, which contains fibrous tissue and immature isolated trabeculae composed of woven bone, is expected to display an interesting TIC. The purpose of this study was to assess the utility of TICs for differentiating between the abovementioned lesions, which have similar histopathological components. 相似文献
942.
Tereza C S Brant Carolina T Yoshida Tomas de S. Carvalho Marina L Nicola Jocimar A Martins Lays M Braga Regiani C de Oliveira Vilma Leyton Carmen S de André Paulo H N Saldiva Bruce K Rubin Naomi K Nakagawa 《Clinics (S?o Paulo, Brazil)》2014,69(12):867-870
OBJECTIVES:There is evidence that outdoor workers exposed to high levels of air pollution exhibit airway inflammation and increased airway symptoms. We hypothesized that these workers would experience increased airway symptoms and decreased nasal mucociliary clearance associated with their exposure to air pollution.METHODS:In total, 25 non-smoking commercial motorcyclists, aged 18-44 years, were included in this study. These drivers work 8-12 hours per day, 5 days per week, driving on urban streets. Nasal mucociliary clearance was measured by the saccharine transit test; airway acidification was measured by assessing the pH of exhaled breath condensate; and airway symptoms were measured by the Sino-nasal Outcome Test-20 questionnaire. To assess personal air pollution exposure, the subjects used a passive-diffusion nitrogen dioxide (NO2) concentration-monitoring system during the 14 days before each assessment. The associations between NO2 and the airway outcomes were analyzed using the Mann-Whitney test and the Chi-Square test. Clinicaltrials.gov: .RESULTS:Compared with clearance in healthy adult males, mucociliary clearance was decreased in 32% of the motorcyclists. Additionally, 64% of the motorcyclists had airway acidification and 92% experienced airway symptoms. The median personal NO2 exposure level was 75 mg/m3 for these subjects and a significant association was observed between NO2 and impaired mucociliary clearance (p = 0.036).CONCLUSION:Non-smoking commercial motorcyclists exhibit increased airway symptoms and airway acidification as well as decreased nasal mucociliary clearance, all of which are significantly associated with the amount of exposure to air pollution. NCT01976039相似文献
943.
Ivana Perkovi? Martina Kne?evi? Romi? Marina Peri? Silvana Juki? Krmek 《Acta stomatologica Croatica》2014,48(4):258-267
Objectives
to compare the level of anxiety reported by patients and assessed by dentists. Also, the expected and actual pain during the treatment perceived by the patient and dentist were assessed.Methods
sixty six endodontic patients filled in two questionnaires, prior to and after the treatment, so did their therapists. The first set of questions for patients was regarding demographics, the frequency of dental visits, the level of anxiety and expectations about the level of pain. Before the treatment, dentists estimated the level of patients'' anxiety and the expected intensity of pain. After the treatment, the patients evaluated the level of experienced pain and dentists'' empathy during the treatment, while dentists reassessed the intensity of patients'' pain.The data were statistically analysed by t-test for paired samples and by Spearmans''s Rho correlation coefficient at level of significance set at 0.05.Results
Patients'' expectation of pain intensity was higher than the actual pain during the treatment (t-test=3.540, p=0.001). There was no difference in the level of pain which dentists expected and their perception of pain during the procedure. There was a statistically significant correlation between the patients'' level of anxiety and recognition of it by dentists (Spearman Rho=0.460, p<0.001). A higher level of anxiety increased the expected intensity of pain (Spearman Rho=0.401, p=0.001). Actual intensity of pain was not significantly associated with dental anxiety (Spearman Rho=0.080, p=0.524).Conclusion
Since the level of dental anxiety was associated with the increased intensity of expected pain, a vicious cycle of pain and anxiety may be terminated by giving positive information to the patient before and during endodontic procedures. 相似文献944.
Marina Angélica MARCIANO Roberto Brand?o GARCIA Bruno Cavalini CAVENAGO Paloma Gagliardi MINOTTI Raquel Zanin MIDENA Bruno Martini GUIMAR?ES Ronald ORDINOLA-ZAPATA Marco Antonio Hungaro DUARTE 《Journal of applied oral science : revista FOB》2014,22(4):268-273
Objectives
To investigate if there is a relation between the increase of bismuth oxide and the decrease of pH levels and an intensification of toxicity in the Portland cement.Material and Methods
White Portland cement (WPC) was mixed with 0, 15, 20, 30 and 50% bismuth oxide, in weight. For the pH level test, polyethylene tubes were filled with the cements and immersed in Milli-Q water for 15, 30 and 60 days. After each period, the increase of the pH level was assessed. For the biocompatibility, two polyethylene tubes filled with the cements were implanted in ninety albino rats (n=6). The analysis of the intensity of the inflammatory infiltrate was performed after 15, 30 and 60 days. The statistical analysis was performed using the Kruskal-Wallis, Dunn and Friedman tests for the pH level and the Kruskal-Wallis and Dunn tests for the biological analysis (p<0.05).Results
The results showed an increase of the pH level after 15 days, followed by a slight increase after 30 days and a decrease after 60 days. There were no significant statistical differences among the groups (p>0.05). For the inflammatory infiltrates, no significant statistical differences were found among the groups in each period (p>0.05). The 15% WPC showed a significant decrease of the inflammatory infiltrate from 15 to 30 and 60 days (p<0.05).Conclusions
The addition of bismuth oxide into Portland cement did not affect the pH level and the biological response. The concentration of 15% of bismuth oxide resulted in significant reduction in inflammatory response in comparison with the other concentrations evaluated. 相似文献945.
946.
947.
Marina Yu. Stogniy Olga N. Kazheva Denis M. Chudak Gennady V. Shilov Oleg A. Filippov Igor B. Sivaev Andrey V. Kravchenko Vladimir A. Starodub Lev I. Buravov Vladimir I. Bregadze Oleg A. Dyachenko 《RSC advances》2020,10(5):2887
The C-methylthio derivatives of cobalt bis(dicarbollide) were synthesized by reaction of anhydrous CoCl2 with nido-carborane [7-MeS-7,8-C2B9H11]− and isolated as a mixture of rac-[1,1′-(MeS)2-3,3′-Co(1,2-C2B9H10)2]− and meso-[1,2′-(MeS)2-3,3′-Co(1,2-C2B9H10)2]− isomers. The structures of both isomers were studied using DFT quantum chemical calculations. The most preferable geometry of rotamers and the stabilization energy of C-methylthio derivatives of cobalt bis(dicarbolide) were calculated. The (BEDT-TTF)[1,1′-(MeS)2-3,3′-Co(1,2-C2B9H10)2] salt was prepared and its structure was determined by single crystal X-ray diffraction. The cisoid conformation of the rac-[1,1′-(MeS)2-3,3′-Co(1,2-C2B9H10)2]− anion is stabilized by short intramolecular CH⋯S hydrogen and BH⋯S chalcogen bonds between the dicarbollide ligands, that is in good agreement with the data of quantum chemical calculations.The C-methylthio derivatives of cobalt bis(dicarbollide) rac-[1,1′-(MeS)2-3,3′-Co(1,2-C2B9H10)2]− and meso-[1,2′-(MeS)2-3,3′-Co(1,2-C2B9H10)2]− were synthesized and studied by DFT calculations and X-ray diffraction. 相似文献
948.
Sergio Daga Jie Ding Constantinos Deltas Judy Savige Beata S. Lipska-Zitkiewicz Julia Hoefele Frances Flinter Daniel P. Gale Marina Aksenova Hirofumi Kai Laura Perin Moumita Barua Roser Torra Jeff H. Miner Laura Massella Danica Galei Ljubanovi Rachel Lennon Andr B. Weinstock Bertrand Knebelmann Agne Cerkauskaite Susie Gear Oliver Gross A. Neil Turner Margherita Baldassarri Anna Maria Pinto Alessandra Renieri 《European journal of human genetics : EJHG》2022,30(5):507
949.
In this paper, a universal technology is proposed for processing low-titanium mineral raw material—apatite-nepheline ore waste, including its treatment with sulfuric or hydrochloric acid in a two-stage mode with a sequential increase in the concentration. This technique allowed us to remove nepheline and apatite in the first stage and achieve a titanium mineral content of TiO2 of more than 30%; in the second stage, we were able to convert the titanium into its precursors—titanyl sulfate monohydrate TiOSO4·H2O and a hybrid rutile-silica composition. The key stage in the sorbent synthesis is the reaction of the precursor with a phosphoric acid solution. The preferred sequence of operations begins with the mechanical activation of the precursor, causing morphological changes in it, and subsequent treatment with phosphoric acid at different concentrations under atmospheric conditions and in an autoclave, accompanied by phase transformations. Conditions for the chemical reactions which regulated the composition and structure of the final product and, accordingly, its sorption activity were found. With the help of XFA, the phase compositions of the sorbents were identified, including the individual crystalline phase α-TiP obtained from TS or the crystalline phase αTi(HPO4)2∙H2O, which is in an amorphous silica matrix obtained from a rutile–silica composition. 相似文献
950.