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11.
Thomas von Arx Scott Lozanoff Pedram Sendi Michael M. Bornstein 《Surgical and radiologic anatomy : SRA》2013,35(9):783-790
Purpose
The anterior maxilla, sometimes also called premaxilla, is an area frequently requiring surgical interventions. The objective of this observational study was to identify and assess accessory bone channels other than the nasopalatine canal in the anterior maxilla using limited cone beam computed tomography (CBCT).Methods
A total of 176 cases fulfilled the inclusion criteria comprising region of interest, quality of CBCT image, and absence of pathologic lesions or retained teeth. Any bone canal with a minimum diameter of 1.00 mm other than the nasopalatine canal was analyzed regarding size, location, and course, as well as patient gender and age.Results
A total of 67 accessory canals ≥1.00 mm were found in 49 patients (27.8 %). A higher frequency of accessory canals was observed in males (33.0 %) than in females (22.7 %) (p = 0.130). Accessory canals occurred more frequently in older rather than younger patients (p = 0.115). The mean diameter of accessory canals was 1.31 ± 0.26 mm (range 1.01–2.13 mm). Gender and age did not significantly influence the diameter. Accessory canals were found palatal to all anterior teeth, but most frequently palatal to the central incisors. In 56.7 %, the accessory canals curved superolaterally and communicated with the ipsilateral alveolar extension of the canalis sinuosus.Conclusions
The study confirms the presence of bone channels within the anterior maxilla other than the nasopalatine canal. More than half of these accessory bone canals communicated with the canalis sinuosus. From a clinical perspective, studies are needed to determine the content of these accessory canals. 相似文献12.
Raabe Clemens Bornstein Michael M. Ducommun Julien Sendi Pedram von Arx Thomas Janner Simone F. M. 《Clinical oral investigations》2021,25(6):3513-3525
Clinical Oral Investigations - To assess survival rates and frequency of complications for immature and mature autotransplanted teeth after at least 1 year in function. All consecutive patients who... 相似文献
13.
Jafar Soltani Bahram Nikkhoo Jabar Khormehr Pedram Ataee Mohammad-Saeid Hakhamaneshi Fardin Gharibi 《Iranian journal of pediatrics.》2014,24(6):745-752
Objective:
Helicobacter pylori (H. pylori) is the most common chronic bacterial infection in humans. Chronic colonization increases the risk of duodenal ulcer and gastric cancer. The risk factors for acquiring the infection have been extensively studied. However, there are conflicting results on the role of breastfeeding in the prevention of H. pylori infection. We conducted a study to evaluate the effects of breastfeeding on the H. Pylori infection in Kurdish children in Sanandaj, IR Iran.Methods:
A historical cohort study was carried out from January 2011 through December 2012. Totally 221 children who were going to attain 2 years old during the study period were randomly enrolled. They were divided into two groups, i.e. breastfed and non-breastfed. We used H. pylori stool antigen test to detect infection in the selected group of children after age of 2 years and cessation of breastfeeding. Each group was subdivided into two subgroups, infected and non-infected. The associations of breastfeeding with H. pylori infection was assessed using statistical software.Findings:
We found no difference in the odds of infection between breastfed and non-breastfed groups (OR=0.809, 95% CI [0.453–1.444]). An association between age and the prevalence of infection was found (P=0.008). There was an increase in the odds of infection as the family size grew (OR=1.93, 95% CI [1.04–3.6]) as well as increasing housing density (OR=2.12, 95% CI [1.10–4.10]).Conclusion:
The data suggests that breastfeeding in infancy does not protect against H. pylori infection for long duration among studied children in Iran. The protective effects of breastfeeding, if any, are at most transient. 相似文献14.
15.
16.
Morassa Mohseni Justin Cidado Sarah Croessmann Karen Cravero Ashley Cimino-Mathews Hong Yuen Wong Rob Scharpf Daniel J. Zabransky Abde M. Abukhdeir Joseph P. Garay Grace M. Wang Julia A. Beaver Rory L. Cochran Brian G. Blair D. Marc Rosen Bracha Erlanger Pedram Argani Paula J. Hurley Josh Lauring Ben Ho Park 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(49):17606-17611
17.
Armin Hosseini Razavi Pedram Azimzadeh Seyed Reza Mohebbi Seyed Masoud Hosseini Sara Romani Mahsa Khanyaghma Yasin Hatami Afsaneh Sharifian Mohammad Reza Zali 《Hepatitis monthly》2014,14(4)
Background:
Chronic hepatitis B is one of the world''s major health concern. The etiological agent of this infection is hepatitis B virus (HBV), which can evade the immune system response. Transforming growth factor beta 1 (TGF-β1) can act against HBV by suppressing the viral replication. The TGF-β1 also plays an important role in preventing liver damage in chronically HBV infected patients.Objectives:
In this study, the association of TGF-β1 +915G/C and -509C/T gene polymorphisms with chronic hepatitis B was evaluated in Iranian patients.Materials and Methods:
A population-based case–control study was conducted in Taleghani Hospital, Tehran. A number of 220 patients with chronic hepatitis B and the same number of healthy control subjects were designated the case and the control groups. The PCR-Restriction Fragment Length Polymorphism Method (PCR-RFLP) method was used for genotyping both polymorphisms. Ten percent of the control samples were sequenced to confirm the results.Results:
No statically significant differences in genotype distribution and allele frequency were observed for both polymorphisms between healthy controls and patients with chronic hepatitis B.Conclusions:
There was no association between TGF-β1 -509C/T and +915G/C polymorphisms with chronic hepatitis B and it seems that these changes don not play a significant role in increasing the risk of chronic infection in Iranian patients. 相似文献18.
Frei M Engel Brügger O Sendi P Reichart PA Ramseier CA Bornstein MM 《Clinical oral investigations》2012,16(3):755-760
The present study validated the accuracy of data from a self-reported questionnaire on smoking behaviour with the use of exhaled carbon monoxide (CO) level measurements in two groups of patients. Group 1 included patients referred to an oral medicine unit, whereas group 2 was recruited from the daily outpatient service. All patients filled in a standardized questionnaire regarding their current and former smoking habits. Additionally, exhaled CO levels were measured using a monitor. A total of 121 patients were included in group 1, and 116 patients were included in group 2. The mean value of exhaled CO was 7.6?ppm in the first group and 9.2?ppm in the second group. The mean CO values did not statistically significantly differ between the two groups. The two exhaled CO level measurements taken for each patient exhibited very good correlation (Spearman's coefficient of 0.9857). Smokers had a mean difference of exhaled CO values of 13.95?ppm (p?<?0.001) compared to non-smokers adjusted for the first or second group. The consumption of one additional pack year resulted in an increase in CO values of 0.16?ppm (p?=?0.003). The consumption of one additional cigarette per day elevated the CO measurements by 0.88?ppm (p?<?0.001). Based on these results, the correlations between the self-reported smoking habits and exhaled CO values are robust and highly reproducible. CO monitors may offer a non-invasive method to objectively assess current smoking behaviour and to monitor tobacco use cessation attempts in the dental setting. 相似文献
19.
Ali Asghar Moshtaghie Pedram Malekpouri Minoo Moshtaghie Maryam Mohammadi-nejad Mohsen Ani 《Neurological sciences》2013,34(9):1639-1650
The probable protective effects of copper on the acetylcholinesterase activity and the catecholamine levels in cerebellum, cortex and mid-brain of rat, which was intoxicated by aluminum, were studied during short and long terms. In this respect, male Wistar rats weighing 200–250 g were received daily intraperitoneal doses of aluminum, copper and also combined doses of both metals for 15 days (Al 10 mg kg?1 BW and Cu 1 mg kg?1 BW), 30 days (Al 5 mg kg?1 BW and Cu 0.5 mg kg?1 BW) and 60 days (Al 1 mg kg?1 BW and Cu 0.1 mg kg?1 BW), respectively. The results obtained from the short period of exposure (15 days) showed that aluminum produced significant (P < 0.05) decreases in the acetylcholinesterase activity by 24.14, 23.30 and 25.81 %. Similarly, the catecholamine levels were reduced by 10.69, 12.25 and 12.64 % in cerebellum, cortex and mid-brain, respectively. Treatment with copper increases both acetylcholinesterase activity and catecholamine contents of cerebellum, cortex and mid-brain. Simultaneous injection of copper and aluminum increased both acetylcholinesterase activity and catecholamine contents in all three parts of rat brain when compared to aluminum-treated group. Same results were also observed following 30 and 60 days of exposures. In overall, it has been found that copper may have a protective-like ability to hinder aluminum toxicity in the brain. 相似文献
20.
Thomas von Arx Monika Friedli Pedram Sendi Scott Lozanoff Michael M. Bornstein 《Journal of endodontics》2013