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81.
Deeply seated aggressive fibromatosis also termed as desmoid tumors are rare tumors that invade surrounding structures. Although they never metastasize mortality rate may be as high as 10% due to their aggressive local behavior. Intraabdominal desmoid tumors are usually associated with familial poliposis coli and have a high recurrence rate regardless of the therapy instituted. Sporadic cases are very rare and generous surgical excision may be of benefit. We hereby report 2 siblings with sporadic pancreatic desmoid tumors who also harbor additional fibrotic masses in the pelvis. Although in previously reported cases there is usually a triggering event such as trauma, in the present cases there was no inciting event. Furthermore, the cases are without an associated FAP history, which provides the first clinical clue of a possible genetic determinant in this rare disorder.  相似文献   
82.
Ochratoxin A (OTA) is a mycotoxin produced by several fungi. Many foods can be contaminated by OTA, which is consequently found in the blood of humans and animals. It is known that OTA accumulates in the brain. The aim of this study was to investigate the effects of OTA on the brain. For this purpose, the effect of OTA on N-methyl-D-aspartate (NMDA) receptor subunits 2A (NR2A) and 2B (NR2B) in the hippocampus and the protective effect of melatonin were investigated. Three groups of eight rats were used: controls, OTA-treated rats (OTA dose 289 microg/kg per day) and OTA+melatonin-treated rats (melatonin dose 10 mg/kg per day). After four weeks of treatment, electrophoretic examinations were performed using SDS-polyacrylamide gel electrophoresis and Western blotting of hippocampal homogenates of the different groups. The concentrations of NR2A and NR2B in the OTA group were significantly lower than in the control group. The concentration of NR2B was significantly increased when melatonin was co-administered with OTA compared with OTA only. There was also a significant increase in NR2A levels when melatonin was co-administered with OTA. As a result, subchronic administration of OTA reduced hippocampal NMDA receptor subunits 2A and 2B concentrations in rats. It was thought that this alteration might affect cognitive functions because hippocampal NMDA receptors are involved in the memory and learning processes. Melatonin exhibited a partially protective effect on NR2A and NR2B against OTA.  相似文献   
83.
To obtain an effective and compliance-free molar distalization without an anchorage loss, we designed the bone-anchored pendulum appliance (BAPA). The aim of this study was to evaluate the stability of the anchoring screw, distalization of the maxillary molars, and the movement of teeth anterior to maxillary first molars. The study group comprised 10 patients (mean age 13.5 +/- 1.8 years) with Class II molar relationship. A conventional pendulum appliance was modified to obtain anchorage from an intraosseous screw instead of the premolars. The screw was placed in the anterior paramedian region of the median palatal suture. Skeletal and dental changes were measured on cephalograms, and dental casts were obtained before and after distalization. A super Class I molar relationship was achieved in a mean period of 7.0 +/- 1.8 months. The maxillary first molars distalized an average of 6.4 +/- 1.3 mm in the region of the dental crown by tipping distally an average of 10.9 degrees +/- 2.8 degrees . Also, the maxillary second premolar and first premolar moved distally an average of 5.4 +/- 1.3 mm and 3.8 +/- 1.1 mm, respectively. The premolars tipped significantly distally. No anterior incisor movement was detected. The BAPA was found to be an effective, minimally invasive, and compliance-free intraoral distalization appliance for achieving both molar and premolar distalization without any anchorage loss.  相似文献   
84.
Self-etching primers are now considered the new generation of dentin bonding systems that modify and incorporate the bacteria-containing smear layer into their bonding mechanism. The antibacterial effects of the self-etching primers Clearfil SE Bond, Mac Bond, Imperva FL Bond, One-Up BondF and Prompt L-Pop were evaluated using the bacteria Streptococcus mutans ATCC25175, Peptostreptococcus anaerobius, Peptostreptococcus prevotii, Peptostreptococcus asaccharolyticus, Lactobacillus acidophilus, Lactobacillus catenaforme, Lactobacillus jensenii, Actinomyces odontolyticus, Porphyromonas endodontalis, Clostridium ramosum, Prevotella oris, Prevotella denticola and Fusobacterium nucleatum, with a disk diffusion method. A single-bottle total-etch dentin adhesive (Excite) was used for comparisons and chlorhexidine (0.2%) was used as the positive control. After incubation, zones of inhibited bacterial growth were observed. One-Up BondF, Prompt L-Pop and Excite showed growth inhibition for all bacterial strains. The bonding agents of Clearfil SE Bond, Mac Bond and Imperva FL Bond were unable to inhibit the growth of Lactobacillus jensenii and Actinomyces odontolyticus, while the primers of these systems produced inhibition halos to all tested microorganisms greater than that of chlorhexidine.  相似文献   
85.
The aim of this study was to investigate the susceptibility to four antifungal agents: ketoconazole, terbinafine, itraconazole and fluconazole, of the different species of dermatophyte strains isolated from clinical specimens. A total of 128 specimens were collected from toe nail, foot, inguinal region, trunk, hands and head. The dermatophytes tested included Trichophyton rubrum 108 (84.4%), Trichophyton mentagrophytes 11 (8.6%), Epidermophyton floccosum 5 (3.9%), Microsporum canis 2 (1.5%) and Trichophyton tonsurans 2 (1.5%). The mean minimum inhibitory concentrations (MIC) for the five species of dermatophytes ranged between 0.09-1.12 microg/mL for ketoconazole, 0.04-0.27 microg/mL for terbinafine, 0.08-0.43 microg/mL for itraconazole and 16.18-24.0 microg/mL for fluconazole. In vitro analysis of antifungal activity of these agents would also allow for the comparison between different systemic antifungals, which in turn may clarify the reasons for the lack of clinical response or serve as an effective therapy for patients with chronic infection.  相似文献   
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BACKGROUND: We retrospectively reviewed our experience with retrograde ureteroscopy (URS) and a pneumatic lithotriptor in 160 patients with distal ureteral stones to determine whether prior extracorporeal shock wave lithotripsy (ESWL) is a limiting factor in the ureteroscopic procedure. METHODS: From January 1999 to September 2000, we performed URS and pneumatic lithotripsy in 160 patients with distal ureteral stones. Seventy-four patients were treated with URS primarily (Group 1), while the remaining 86 patients received URS only after ESWL had failed (Group 2). For URS and lithotripsy, we used a 9.5 French rigid instrument and vibrolith (Elmed, Ankara, Turkey). RESULTS: In Group 1, 73 of 74 patients (98.6%) were treated successfully by URS alone, as were 81 of 86 patients (94.4%) in Group 2. Impacted stones were also observed in 17 patients from Group 2. In these patients, endoscopic observation revealed edematous inflammation above and below the calculus. Ureteral perforation occurred in one patient from Group 2, which required surgical repair. There was no significant difference in the stone-free rates of the two groups t = 1.4 < 1.96t( infinity,0.05). CONCLUSION: Our data demonstrate that when ESWL fails, URS and pneumatic lithotripsy is as safe and effective as primary URS. Pneumatic lithotripsy also seems to be an effective treatment modality for impacted stones.  相似文献   
89.
Clinical, radiographic, and operative findings in two children with intra-osseous pseudomeningocele of the occipital bone due to cranial trauma are presented here, along with a literature review of this uncommon radiologic entity.  相似文献   
90.
INTRODUCTION: The aims of this study were to determine the size of individual permanent teeth, tooth-size ratios for the maxillary and mandibular dentitions, and sex differences for those variables in a Turkish population, and to compare the figures obtained with those of the Bolton analysis. METHODS: The data were derived from dental casts of 150 Turkish subjects (72 men, mean age 22.09 +/- 3.11 years; 78 women, mean age, 21.11 +/- 2.08 years) with normal occlusions. The mean, standard deviation, and minimum and maximum values were calculated for individual tooth size, and overall and anterior ratios, separately for men and women. To determine whether there are sex differences in intermaxillary tooth size discrepancies, an independent samples t test was performed. RESULTS: The mesiodistal dimensions of the maxillary teeth showed greater variability than the mandibular teeth, with the first molar dimensions having the greatest variability. The overall and anterior ratios were found to be 89.88 +/- 2.29 and 78.26 +/- 2.61, respectively. A statistically significant sex difference was found only in overall ratio (P < .001). According to Bolton's mean values, a discrepancy in the overall ratio was found in 18% of Turkish normal occlusion subjects, and anterior ratios outside 2 standard deviations from the Bolton mean were found in 21.3% of our sample. CONCLUSIONS: These findings indicate that population-specific standards are necessary for clinical assessments. Bolton's original data do not represent Turkish people, and therefore it is appropriate to use Turkish norms in daily orthodontic practice for Turkish patients.  相似文献   
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