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991.
Formulas that convert speech recognition scores, in percent or proportions, into units based on the arcsine transform have been described previously. This report reviews that work and presents various supplementary equations and tables for calculating and interconverting the proposed units. The relative merits of these data and their application to scores from closed-set tests are also discussed. 相似文献
992.
《Substance use & misuse》2013,48(7):863-867
The use of the narcotic antagonists naltrexone, naloxone, and cyclazocine is reviewed with attention being given to their prospects, problems, side effects, and safety. 相似文献
993.
It has been suggested that environmental exposures and living conditions can explain some of the worldwide variation in atopic disorders. Norway has large environmental contrasts within the country. We compared skin prick sensitization rates among school children living in the southern subarctic and in the northern artic part of Norway. Approximately one quarter of the children were sensitized, mostly against pollen and animal dander, while mite and mould sensitization seemed to be a minor problem. Sensitization rates and profiles were similar in the north and south despite differences in living conditions and environmental exposures. 相似文献
994.
995.
Mineral trioxide aggregate enriched with iron disulfide nanostructures: an evaluation of their physical and biological properties
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Liliana Argueta‐Figueroa José J. Delgado‐García René García‐Contreras Omar Martínez‐Alvarez José Santos‐Cruz Carlos Oliva‐Martínez Laura S. Acosta‐Torres Javier de la Fuente‐Hernández Ma C. Arenas‐Arrocena 《European journal of oral sciences》2018,126(3):234-243
The purpose of this study was to characterize mineral trioxide aggregates (MTA) enriched with iron disulfide (FeS2) nanostructures at different concentrations, and to investigate their storage modulus, radiopacity, setting time, pH, cytotoxicity, and antimicrobial activity. Iron disulfide nanostructures [with particle size of 0.357 ± 0.156 μm (mean ± SD)] at weight ratios of 0.2, 0.4, 0.6, 0.8, and 1.0 wt% were added to white MTA (wMTA). The radiopacity, rheological properties, setting time, and pH, as well as the cytotoxicity (assessed using the MTT assay) and antibacterial activity (assessed using the broth microdilution test) were determined for MTA/FeS2 nanostructures. The nanostructures did not modify the radiopacity values of wMTA (~6 mm of aluminium); however, they reduced the setting time from 18.2 ± 3.20 min to 13.7 ± 1.8 min, and the storage modulus was indicative of a good stiffness. Whereas the wMTA/FeS2 nanostructures did not induce cytotoxicity when in contact with human pulp cells (HPCs) and human gingival fibroblasts (HGFs), they showed bacteriostatic activity against Staphylococcus aureus, Escherichia coli, and Enterococcus faecalis. Adding FeS2 nanostructures to MTA might be an option for improving the root canal sealing and antibacterial effects of wMTA in endodontic treatments. 相似文献
996.
Patrick W. Utz 《Behavioral medicine (Washington, D.C.)》2013,39(4):40-46
This study investigated the effect of varying degrees of therapist presence on outcome measures of a test anxiety program on systematic desensitization. Three treatments, which included face-to-face administration by a therapist, some therapist involvement, and fully automated administration were compared to a waiting list control group. It was found that all three treatments were effective when compared to the control group in terms of reduction of reported anxiety as measured by the STABS. It was noted that clients who used the automated program were more likely to terminate prematurely. It was concluded that, while all of the treatments may be effective in a laboratory setting, the presence of a counselor would seem to be important for the use of this type of program in a service agency. 相似文献
997.
Compensated active noise cancellation earphone for audiometric screening tests in noisy environments
Hung-Yue Chang Ching-Hsing Luo Cheng-Chi Tai 《International journal of audiology》2013,52(11):747-753
AbstractObjective: This study investigated hearing screening tests by using a custom-designed compensated hybrid active noise cancellation (ANC) earphone and compared it with TDH39 and Audiocups audiometric earphones under conditions of quiet, 45?dB HL masking narrowband, wideband speech-shaped, and white noise.Design: The hearing screening tests were conducted to characterise the shifts of screening results under noisy conditions, and real-ear attenuations at thresholds were assessed to quantify real-ear noise reduction performance.Study sample: Twenty-four normal-hearing adults, aged 20–25?years, participated in this study.Results: The ANC earphone exhibited significantly lower/better mean screening results than those of the TDH39 earphone at 250 and 500?Hz and those of the Audiocups earphone at 250?Hz under conditions of narrowband, speech-shaped, and white noise. Compared with the TDH39 earphone at 250 and 500?Hz, applying a hybrid ANC earphone reduced the shifts in screening results by 14.2 and 12.3?dB, respectively, under the narrowband noise condition.Conclusion: This study demonstrated that the compensated hybrid ANC earphone provided lower shifts of screening results than the TDH39 and Audiocups earphones and that it was capable of screening at 250 and 500?Hz from 20?dB HL under 45?dB HL masking narrowband and wideband noise. 相似文献
998.
《Journal of agromedicine》2013,18(3):31-41
ABSTRACT The objective of this study was to estimate the sensitivity of the Colilert® test for detection of different isolates of Escherichia coli (E. coli) O157:H7 and other verotoxin-producing E. coli (VTEC) serotypes from water for potential on-farm food safety application. E. coli isolates evaluated were of human, bovine, porcine, or food origin. The sensitivity of the Colilert® test was 92% overall for the verotoxin-producing serotypes of E. coli. However, none of the E. coli O157:H7 isolates were identified as E. coli. No false-positive results for E. coli were detected. The Colilert® test could be used to screen water supplies for E. coli on the farm, however, an important pathogenic E. coli sero-type is not detected by the Colilert® test. 相似文献
999.
1000.
AbstractInfection from bacterial resistance to antibiotics has given rise to a grave threat to human health in the world. It is vital to developing highly efficient antibacterial materials that are safe and biocompatible with humans and without bacterial resistance. In this study, nanofiber membranes of graphene oxide/polyacrylonitrile (GO/PAN) with highly efficient antibacterial activity were fabricated via electrospinning technique. As the spindle-knot structure of membranes formed by the addition of GO sheets increased, the hydrophilicity and surface roughness increased. The antibacterial test indicated that antibacterial ratios of 3GO/PAN membranes against Escherichia coli and Staphylococcus aureus were 98.5% and 99.6%, respectively after contracting 24?h, with highly efficient antibacterial activity. Furthermore, the E. coli cell structures of adhered to the GO/PAN nanofiber surface changed significantly shrunk and deformed, and the number of S. aureus cell were obviously less contrast than the pure PAN. The main antibacterial mechanism was GO of spindle-knot in nanofiber membranes produced ROS destroyed the physiological activities of the bacteria lead to death. The fabricated GO/PAN nanofiber membrane of this study is promising to develop to a kind of novel antibacterial materials. 相似文献