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32.
Objective:To determine if density measurements of several maxillary regions in Hounsfield Units (HU) and outcomes of rapid maxillary expansion (RME) are correlated. Is correlation powerful enough to give us direct information about maxillary resistance to RME?Materials and Methods:Twenty-two computed tomographic (CT) scans (14 years) are used in this archive study. Two CT records were collected, one before RME (T1) and one after 3 months of retention period (T2). Maxillary measurements were made using dental and skeletal landmarks in first molar and first premolar slides to measure the effects of RME. Density of midpalatal suture (MPSD) and segments of maxillary bone is measured in HU at T1. Correlation analysis was conducted between density measurements and maxillary variables. Regression analysis was then performed for variables that showed positive correlation.Results:There was no correlation between density and skeletal measurements. Intermolar angle (ImA) in molar slice showed statistically significant correlation with density measurements. The ImA variable showed the highest correlation with MPSD in frontal section (r = 0.669, P < .01).Conclusions:There is correlation of 32.1–43.3% between density measurements and ImA increase. Our density measurements explain a certain percentage of ImA increase, but density is not the only and definitive indicator of changes after RME. 相似文献
33.
Testicular tumours have many different manifestations, including hydrocele formation. Herein, we present an extremely rare case of testicular mesothelioma presenting with left hydrocele, but without risk factors. Left radical inguinal orchidectomy was performed, and pathological examination revealed a malignant mesothelioma of the tunica vaginalis of the testis. No infiltration of the spermatic cord was evident, and upon advanced radiological evaluation, no sign of metastasis was detected. Follow-up was still ongoing in our urology outpatient clinic at the time of this report. Although hydrocele is a simple and common condition that is easy to diagnose, a detailed investigation should be performed. Thus, when encountering a patient with hydrocele, the clinician should evaluate the possibility of the presence of an underlying testicular/paratesticular tumour, including a rare one such as mesothelioma of the tunica vaginalis. 相似文献
34.
There is an increasing recognition of the association between chronic hepatitis C virus (HCV) infection and glomerular diseases.
Renal complications may be the presenting manifestation of HCV infection. Patients may present with systemic vasculitis secondary
to cryoglobulinemia, or they may present with proteinuria, microscopic hematuria, acute renal failure, or nephrotic syndrome.
The pathogenesis of HCV-associated renal disease remains incompletely understood; however, deposition of HCV-containing circulating
immune complexes in the glomeruli (ie, subendothelial space and mesangium) seems to play an important role. The most common
renal pathology associated with HCV infection is type I membranoproliferative glomerulonephritis with or without cryoglobulinemia.
In patients who do not have significant renal impairment, combination therapy with interferon-á and ribavirin is the treatment
of choice. The experience with this combination therapy is quite limited in patients with renal impairment. Prolonged courses
of high-dose interferon-á therapy have been successfully used for these patients; however, relapse of HCV viremia and recurrence
of renal disease is common after discontinuation of therapy. 相似文献
35.
Fereydoun DAVATCHI Farhad SHAHRAM Abdolhadi NADJI Cheyda CHAMS‐DAVATCHI Hormoz SHAMS Ma'ssoomeh AKHLAGHI Bahar Sadeghi ABDOLLAHI Naghmeh ZIAIE 《International journal of rheumatic diseases》2006,9(3):238-243
Aim: To analyse the performance of existing diagnosis/classification criteria for Behcet's disease (BD) in Iranian patients. There are 13 sets: Curth (1946), Hewitt (1969), Mason and Barnes (1969), Hewitt revised (1971), Japan (1972), Hubault and Hamza (1974), O'Duffy (1974), Cheng and Zhang (1980), Dilsen (1986), Japan revised (1988), International (1990), Iran (1993), Classification Tree (1993), and Dilsen revised criteria (2000). Methods: All patients from the Behcet's Disease Registry (5666) and control patients (2406) entered the study. Sensitivity, specificity and accuracy were calculated. Results: The most sensitive was Curth criteria with (99.7%), followed by Classification Tree (97.3%), Zhang (93.5%), Iran (91.4%), Japan revised (86.4%), Japan (85.3%), Dilsen (83.7%), Hubault and Hamza (81.6%), Dilsen revised (81.2%), International criteria (79.8%), Hewitt (73.8%), O'Duffy (70.7%), and Masson and Barnes (65.7%). The most specific was Masson and Barnes (99.6%), followed by the International criteria (98.3%), Dilsen revised (98.2%), O'Duffy (97.6%), Japan (97.1%), Japan revised (97%), Classification Tree (96.7%), Hewitt (95.8%), Iran (95.8%), Zhang (92.4%), Dilsen (91.4%), Hubault (90.8%), and Curth (78.6%). The most accurate criteria was Classification Tree (97.1%), followed by Curth (93.4%), Zhang (93.1%), Iran (92.7%), Japan revised (89.6%), Japan (88.8%), Dilsen revised (86.2%), Dilsen (86%), International criteria (85.3%), Hubault (84.3%), Hewitt (80.4%), O'Duffy (78.8%), and Mason and Barnes (75.8%). Discussion: Among the existing criteria, the best to classify Iranian patients is the Classification Tree. The second most accurate is Curth criteria. The difference is statistically significant. Further, Curth criteria is not optimized, having very high sensitivity and low specificity. 相似文献
36.
PURPOSE
The purpose of this report was to evaluate the effect of the fabrication method and material type on the fracture strength of provisional crowns.MATERIALS AND METHODS
A master model with one crown (maxillary left second premolar) was manufactured from Cr-Co alloy. The master model was scanned, and the data set was transferred to a CAD/CAM unit (Yenamak D50, Yenadent Ltd, Istanbul, Turkey) for the Cercon Base group. For the other groups, temporary crowns were produced by direct fabrication methods (Imident, Temdent, Structur Premium, Takilon, Systemp c&b II, and Acrytemp). The specimens were subjected to water storage at 37℃ for 24 hours, and then they were thermocycled (TC, 5000×, 5-55℃) (n=10). The maximum force at fracture (Fmax) was measured in a universal test machine at 1 mm/min. Data was analyzed by non-parametric statistics (α=.05).RESULTS
Fmax values varied between 711.09-1392.1 N. In the PMMA groups, Takilon showed the lowest values (711.09 N), and Cercon Base showed the highest values (959.59 N). In the composite groups, Structur Premium showed the highest values (1392.1 N), and Acrytemp showed the lowest values (910.05 N). The composite groups showed significantly higher values than the PMMA groups (P=.01).CONCLUSION
Composite-based materials showed significantly higher fracture strengths than PMMA-based materials. The CAD-CAM technique offers more advantages than the direct technique. 相似文献37.
Wah-Kheong Chan Norhaniza Bahar Hamizah Razlan Anushya Vijayananthan Pavai Sithaneshwar Khean-Lee Goh 《Hepatology International》2014,8(1):121-127
Purpose
Previous studies on multiracial Malaysian populations found inordinately high prevalence of NAFLD among Malays and Indians. Whether the prevalence of NAFLD is different among young adults of different ethnic origins is not known. We aimed to determine racial differences in NAFLD in a young multiracial Malaysian population and associated factors.Methods
This was a cross-sectional study on medical students from the University of Malaya. Diagnosis of NAFLD was by transabdominal ultrasonography and following exclusion of significant alcohol intake and other causes of chronic liver disease.Results
Data of 469 subjects were analyzed (mean age 23.2 ± 2.4 years, 40.3 % male). The racial distribution was: Chinese 53.9 %, Malay 30.5 % and Indian 15.6 %. The overall prevalence of NAFLD was 7.9 %. Subjects with NAFLD were older, had greater BMI and WC, higher SBP and DBP, higher FBS, serum TG and LDL levels, and lower serum HDL level. The prevalence of NAFLD was higher among males compared to females (17.9 % vs. 3.3 %, p < 0.001). The highest prevalence of NAFLD was seen among Indian and Malay males at 33.3 and 25.5 %, respectively, compared to Chinese males at 6.8 % (p < 0.001). No significant difference was seen among females of different races. Independent factors associated with NAFLD were male gender, obesity and hypertriglyceridemia.Conclusions
The difference in prevalence of NAFLD among the different ethnic groups can be observed as early as young adulthood. An inordinately high prevalence of NAFLD was observed among Malay and Indian males consistent with the higher prevalence of obesity in these groups. 相似文献38.
Fukuta Y Yildiz-Aktas IZ William Pasculle A Veldkamp PJ 《Scandinavian journal of infectious diseases》2012,44(6):414-418
Legionella endocarditis is extremely uncommon, and embolic phenomena have never been reported. We report the first case of Legionella micdadei prosthetic valve endocarditis complicated by brain abscess. A 57-y-old immunocompromised woman with a history of mitral valve replacement developed confusion and left-sided weakness. Brain magnetic resonance imaging showed a 3-cm peripheral-enhancing mass. Transoesophageal echocardiography suggested a perivalvular abscess. Blood cultures and valve cultures were negative. She was diagnosed with 16S rRNA polymerase chain reaction and silver stain, and was discharged with levofloxacin after a redo mitral valve replacement. Twelve cases of Legionella endocarditis were reviewed. Only one case had a native valve, and her endocarditis occurred after pneumonia. All cases were cured. The duration of antibiotic therapy was variable. Legionella species should be considered in the differential diagnosis of culture-negative endocarditis in both immunocompetent and immunocompromised patients. Molecular techniques and silver impregnation stains are useful, especially when cultures using buffered charcoal-yeast extract agar are negative. 相似文献
39.
The aim of this study was to evaluate partial and complete tooth loss and some related demographic factors, and oral health behaviors among Turkish elderly. According to recent censuses, elderly population of Turkey is rapidly growing. There is no nationwide information related to edentulism and natural teeth retention among 65-74 year-old people in Turkey. In this nationwide representative cross-sectional study, 1545 subjects aged 65-74 years were evaluated using the proportional stratified cluster sampling method. The data were collected via a structured, pre-tested face to face administered questionnaire and an oral examination. Chi-square test and binary logistic regression analyses were used to determine the significance of explanatory variables. 48.0% of elderly were edentate. The mean DMF-T was 25.8±8.5. These values were higher in women (p=0.016), older age (p<0.001) and rural individuals (p<0.001). Only 12.4% of the subjects had functional dentition. Age, visiting dentist, and health security were associated with edentulism. Female sex (OR=1.37), 70-74 age group (OR=2.08) and illiteracy (OR=3.25) were the independent factors of not having functional dentition. A reduction in edentulism in elderly may be achieved by the implementation of community programs promoting oral health for the prevention and treatment. 相似文献
40.