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71.
The purpose of the present study was to assess the effect of solvents on root canal transportation in endodontic retreatment. Sixty extracted human permanent mandibular first molars with curved root canals were selected. All of the root canals were prepared using Twisted File Adaptive instruments (SybronEndo, Orange, CA, USA) and filled with gutta‐percha and AH Plus sealer (Dentsply DeTrey, Konstanz, Germany) using the cold lateral compaction technique. The teeth were assigned to four retreatment groups as follows (n = 15): eucalyptol, chloroform, orange oil and control. The canals were scanned using cone‐beam computed tomography scanning before and after instrumentation. The chloroform group showed a significantly higher mean transportation value than the orange oil and control groups at the 3 and 5 mm levels (P = 0.011 and P = 0.003, respectively). There was no significant difference among the orange oil, eucalyptol and control groups in terms of canal transportation (P > 0.61). The chloroform led to more canal transportation than the eucalyptol and orange oil during endodontic retreatment.  相似文献   
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Purpose

In temporomandibular disorders (TMDs), unless splints are effective, combined therapies are performed. The aim of this study is to show the effectiveness of the local anaesthethic injections (trigger point injections) to the masticatory muscles.

Materials and methods

The study was composed of TMD patients and the predictor variables were therapy combinations including stabilization splint (SS) therapy, SS+trigger point injection therapy (TPI) and arthrocentesis. The primary outcome variables were pain and jaw movements. The follow-ups were done at 1st and 3rd months. 56 patients who were treated for TMD with only SS or combined therapies were included in the study. The effects of additional TPIs were compared to SS therapy alone. Also the effect of arthrocentesis was evaluated too.

Results

All groups revealed significant decreases in pain scores. Decreases in mouth openings were observed in some of the patients in the injection groups.

Conclusion

The combined treatment method in which the injections were applied at shorter time intervals, was a more effective method for decreasing VAS scores in TMD patients in this study but further studies are required.  相似文献   
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Terpolymerizations of polar vinyl monomers, acrylonitrile, methyl acrylate, or methyl methacrylate with butadiene and styrene in the presence of ethylaluminium dichloride, zinc chloride, or other Lewis acids were carried out. The yield and the contents in monomer units of the terpolymer and the yields of the polar vinyl monomer/butadiene 1,4-cycloaddition byproduct formed in these systems were determined. Butadiene conversions in the above terpolymerizations and 1,4-cycloaddition side reactions were related to those in the copolymerization and 1,4-cycloaddition proceeding in corresponding binary systems without styrene. The results are discussed in terms of a radical polymerization and a polar 1,4-cycloaddition mechanisms.  相似文献   
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Introduction Diffusion-weighted imaging (DWI) is usually performed before injection of intravenous paramagnetic contrast medium. Occasionally, it may be necessary to perform or to repeat DWI after such administration. Our purpose was to evaluate the effect of intravenous gadodiamide (Gd [DTPA-BMA]) on DWI.Methods DWI was performed on 88 brain lesions immediately before, immediately after, and 5–10 min following the end of 0.1 mmol/kg Gd [DTPA-BMA] administration. Signal-to-noise ratios (SNRs) and contrast-to-noise ratios (CNRs) of the lesions, and the SNRs of normal brain tissue were calculated on b=0 s/mm2 and b=1,000 s/mm2 DW images. Apparent diffusion coefficient (ADC) values of the lesions were measured on ADC maps. A paired t-test was used to determine the significance of differences between the values before and after administration of contrast medium.Results The lesions consisted of 23 intraaxial and 11 extraaxial masses, 19 ischemic strokes, 15 intracranial hemorrhages and 20 demyelinating lesions. Images before and after contrast administration were not significantly different regarding SNRs and CNRs on DWI. This statement was also true for strongly enhanced lesions. However, ADC values significantly decreased after contrast medium injection on early post-contrast DWI in normal brain tissue (1%, P<0.049) and (3%, P<0.008) in lesions. By contrast, on late images, ADC values were normalized.Conclusion Contrast medium injection had significant and time-dependent effects on ADC values. Therefore, only pre-contrast and late DW images should be used in quantitative ADC studies.  相似文献   
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The first identification of Neospora caninum infection in aborted bovine foetuses in Romania is reported. Nine aborted foetuses were collected from a dairy farm. The foetal age of foetuses was between 3 and 7 months. A 7-month-old foetus was mummified. N. caninum DNA Nc-5 region was amplified from samples extracted from brain tissues of three (33.3%) aborted foetuses. The foetal ages of PCR positive foetuses were 3, 4 and 7 months (mummified). No specific lesions or tissue cysts were found to the histological examination, because of advanced autolysis of brains.  相似文献   
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