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排序方式: 共有3932条查询结果,搜索用时 15 毫秒
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Kee‐Yeon Kum
DDS PhD Qiang Zhu
DDS PhD Kamran Safavi
DMD MEd Yu Gu
MD MSD Kwang‐Shik Bae
DDS PhD Seok Woo Chang
DDS PhD 《Australian endodontic journal : the journal of the Australian Society of Endodontology Inc》2013,39(3):126-130
Ortho mineral trioxide aggregate (MTA) is a mineral aggregate newly developed for perforation repair, root end filling and pulp capping. The aim of this study was to investigate the levels of cadmium (Cd), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni) and zinc (Zn) in Ortho MTA and ProRoot MTA. A total of 0.2 g of each MTA was digested using a mixture of hydrochloric and nitric acids and filtered. Six heavy metals in the resulting filtrates were analyzed by inductively coupled plasma–optical emission spectrometry (n = 5). The results were statistically analyzed using the Mann–Whitney U‐test. The concentrations of Cd, Cu, Fe, Mn, Ni and Zn in Ortho MTA were 0.10, 7.73, 49.51, 2.58, 0.82 and 10.09 p.p.m., respectively. The concentrations of Cd, Cu, Fe, Mn, Ni and Zn in ProRoot MTA were 0.16, 9.38, 1438.11, 74.51, 18.98 and 4.05 p.p.m., respectively. In conclusion, Ortho MTA had lower levels of Cd, Cu, Fe, Mn and Ni than ProRoot MTA. 相似文献
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Describing the relationship between magnitude of response, probability of response, dose and time is difficult using traditional two‐dimensional dose–response curves. We devised a novel way of presentation in four dimensions. Data from a previous study of epidural bupivacaine and ropivacaine given for labour analgesia were re‐analysed. For a range of response magnitudes (5–95% reduction in pain score), estimates of doses associated with probabilities of response 0.05–0.95 were calculated using probit analysis. Three dimensional surface plots were constructed with axes x = magnitude of response, y = probability of response and z = log(dose) at intervals for 30 min. Arithmetic interpolation was used to assemble an animation depicting temporal changes in relationship between variables (fourth dimension). Response–probability–dose curves in three and four dimensions were constructed and presented for both drugs. We believe that this model is more aligned with the logic of clinical dose selection compared with traditional two‐dimensional curves. 相似文献
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Chung JW Lee GH Jeong JY Lee SM Jung JH Choi KD Song HJ Jung HY Kim JH 《Journal of gastroenterology and hepatology》2012,27(3):493-497
Background and Aim: New regimens, including those with new fluoroquinolones, have been developed to overcome the antibiotic resistance of Helicobacter pylori. We aimed to assess the antibiotic resistance rates, as well as the molecular mechanisms of fluoroquinolone resistance, of the clinical isolates obtained in Korea. Methods: The minimal inhibitory concentration (MIC) values of ciprofloxacin, amoxicillin, clarithromycin, metronidazole and tetracycline were determined by the agar dilution method for 185 treatment‐naïve Helicobacter pylori isolates. The resistant strains were evaluated for the presence of point mutations in the quinolone resistance‐determining region (QRDR) of the gyrA and gyrB genes by direct nucleotide sequencing. Results: Twenty‐nine (29/185, 15.7%) of the strains were found to be resistant to ciprofloxacin. The resistance rates to amoxicillin, clarithromycin, metronidazole and tetracycline were 2.2% (four of 185), 10.8% (20 of 185), 30.3% (56 of 185) and 0.5% (one of 185), respectively. The most common mutations in the H. pylori gyrA gene were found at codons corresponding to Asp87 (16/29, 55.2%) and Asn91 (10/29, 34.5%). Conclusions: Primary H. pylori resistance to ciprofloxacin occurred at a high frequency. The fluoroquinolone resistance is most likely mediated through amino acid point mutation in the gyrA gene at Asn87 and Asp91. 相似文献
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Noninvasive parameters and hepatic fibrosis scores in children with nonalcoholic fatty liver disease
AIM: To evaluate the noninvasive parameters and hepatic fibrosis scores in obese children with nonalcoholic fatty liver disease (NAFLD).METHODS: A total of 77 children diagnosed with NAFLD via liver biopsy were included and divided into 2 subgroups according to the histopathologic staging of hepatic fibrosis: mild (stage 0-1) vs significant fibrosis (stage 2-4). Clinical and laboratory parameters were evaluated in each patient. The aspartate aminotransferase (AST)/alanine aminotransferase (ALT) ratio, AST/platelet ratio index (APRI), PGA index, Forns index, FIB-4, NAFLD fibrosis score, and pediatric NAFLD fibrosis index (PNFI) were calculated.RESULTS: No clinical or biochemical parameter exhibited a significant difference between patients with mild and significant fibrosis. Among noninvasive hepatic fibrosis scores, only APRI and FIB4 revealed a significant difference between patients with mild and significant fibrosis (APRI: 0.67 ± 0.54 vs 0.78 ± 0.38, P = 0.032 and FIB4: 0.24 ± 0.12 vs 0.31 ± 0.21, P = 0.010). The area under the receiving operating characteristic curve of FIB4 was 0.81, followed by Forns index (0.73), APRI (0.70), NAFLD fibrosis score (0.58), AST/ALT ratio (0.53), PGA score (0.45), and PNFI (0.41).CONCLUSION: APRI and FIB4 might be useful noninvasive hepatic fibrosis scores for predicting hepatic fibrosis in children with NAFLD. 相似文献
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The increasing proportion of acutely ill hospital patient admissions presenting with a morbidly obese body mass index (BMI ≥ 40 kg m?2) as a comorbidity is an emerging clinical concern. Suboptimal food intake and malnutrition is prevalent in the acute care hospital setting. The energy requirements necessary to prevent malnutrition in acutely ill patients with morbid obesity remains unclear. The aim of this systematic review was to identify studies in the literature that have used indirect calorimetry to measure the resting energy expenditure of patients with morbid obesity to establish their minimum energy requirements and the implications for optimal feeding practices in acutely ill hospitalized patients. A total of 20 studies from PubMed, Cochrane Library and Embase met the inclusion criteria and were reviewed. All articles were graded using the Australian National Health and Medical Research Council levels of evidence and given a quality rating using the American Dietetic Association recommendations. Studies were categorized according to the mean BMI of its subjects. The most commonly measured resting energy expenditures for morbidly obese patients are between 2,000 and 3,000 kcal d?1 (8,400–12,600 kJ d?1). Activity and injury factors of acutely ill morbidly obese patients could result in significantly greater energy requirements for this patient group and are unlikely to be met by standard hospital menus. Establishing the minimum energy requirements for this population group will help inform adequate and accurate energy provision in the acute setting. Outcomes of underfeeding and overfeeding in morbidly obese patients warrant further research. 相似文献