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[en] Two cases of duodenal bezoars are presented. Both were within pseudodiverticula of the duodenal bulbs which were created by chronic active ulcer disease. It is felt that deformed duodenal bulb interfered with transit of the gastrointestinal content causing the formation of bezoar within pseudodiverticula.
[en] Considerable advances have been attained during the last decade in the theoretical and experimental investigation of electrode phenomena in high-pressure arc discharges, in particular, in low-current arcs that occur in high-intensity discharge lamps. The aim of this paper is to deliver a concise review of the understanding achieved and modelling methods developed
[en] Challenges especially in the minimal invasive restorative treatment of teeth require further developments of composite polymerization techniques. These include, among others, the securing of a complete polymerization with moderate thermal stress for the pulp. The aim of this study is to compare current light curing sources with a blue diode laser regarding curing depth and heat generation during the polymerization process. A diode laser (445 nm), a LED, and a halogen lamp were used for polymerizing composite resins. The curing depth was determined according to the norm ISO 4049. Laser output powers of 0.1, 0.5, 1, and 2 W were chosen. The laser beam diameter was adapted to the glass rod of the LED and the halogen lamp (8 mm). The irradiation time was fixed at 40 s. To ascertain ΔT values, the surface and ground area temperatures of the cavities were simultaneously determined during the curing via a thermography camera and a thermocouple. The curing depths for the LED (3.3 mm), halogen lamp (3.1 mm) and laser(0.5/1 W) (3/3.3 mm) showed no significant differences (p < 0.05). The values of ΔTsurface as well as ΔTground also showed no significant differences among LED, halogen lamp, and laser(1 W). The ΔTsurface values were 4.1LED, 4.3halogen lamp, and 4.5 °C for the laser while the ΔTground values were 2.7LED, 2.6halogen lamp, and 2.9 °C for the laser. The results indicate that the blue diode laser (445 nm) is a feasible alternative for photopolymerization of complex composite resin restorations in dentistry by the use of selected laser parameters.
[en] Modern high-pressure discharge lamps are forced to provide instant light and hot relight capabilities - if possible at lower power units. A detailed understanding of the warm-up of high-pressure discharge lamps is therefore required. Complex fluid model codes were developed for the past years including more and more processes like two-dimensional treatment of convection trying to provide a more comprehensive and consistent description of high-pressure discharge lamps. However, there is a lack of experimental data to examine the performance of these models. This work provides a very complete set of geometrical, electrical, spectroscopic, and thermographic data according to the warm-up of a high-pressure mercury discharge lamp that is compared to the results of a state of the art fluid code. Quantitative agreement is achieved for single parameters like wall temperatures. But the paper also reveals the need for further investigations and improvements of the code.
[en] Photochemical degradation of dimethyl phthalate (DMP) in Fe(III)/tartrate/H2O2 system was investigated utilizing fluorescent lamps as the primary light source. Effects of initial pH, light source, and initial concentration of each reactant on DMP photodegradation was examined. The results show that the system was able to effectively photodegrade DMP utilizing visible light. Fluorescent lamp, halide lamp, UV lamp and sunlight could all be used as the light sources. The optimal pH ranged among 3.0-4.0 for the system. Increases of the initial concentrations of Fe(III) and H2O2 accelerated the photodegradation of DMP, whereas excessively high initial tartrate concentration resulted in the decrease of photodegradation efficiency and rate of DMP
[en] Purpose: To evaluate the long-term outcome of patients with esthesioneuroblastoma treated with neoadjuvant or definitive radiotherapy (RT). Methods and Materials: Between 1980 and 2001, 28 patients with histologically confirmed esthesioneuroblastoma underwent RT, with a median dose of 60 Gy (range 38-73). The median age was 58 years (range 16-85). According to the Kadish classification, 4 patients had Stage A, 8 Stage B, and 16 Stage C tumors. Radical resection was performed in 13 cases, in 9 before RT and in 4 after RT because of stable or progressive disease. The outcome analyses included the median age (58 years), Kadish stage, skull base penetration, intraorbital extension, resection status, and total dose (≤60 vs. >60 Gy). Results: After a mean follow-up of 68 months, 54% of patients were free of tumor progression. The 5- and 10-year local progression-free survival rate was 81% and 51%, respectively, and the disease-free survival rate was 70% and 25%, respectively. Four of ten deaths (4/10) were intercurrent, resulting in a cause-specific survival of 77% and 69% at 5 and 10 years, respectively. Radical resection offered significantly better local progression-free survival and disease-free survival (p<0.02). Skull base penetration (p<0.04), intraorbital extension (p<0.04), and Kadish C stage (p<0.06) were important for impaired disease-free survival. Conclusion: Despite doses up to 73 Gy, radical RT cannot replace radical resection, which classifies esthesioneuroblastoma as rather radioresistant. Because of its biology and the high rates of late recurrence, we recommend a radical strategy with resection, high-dose RT, and simultaneous chemotherapy. We are aware that some tumors qualify for palliative treatment only
[en] A case of acute pancreatitis induced by the large impacted duodenal bezoar is presented. The patient under went antrectomy and a Billorth I Operation 3 years ago because of a perforated duodenal ulcer. An obstructing duodenal bezoar, measuring 10 x 6 x 4 cm in dimension, was impacted in the duodenal bulb and the 2nd portion of the duodenum. We suggest that a huge bezoar compressing the ampulla of Vater may be a mechanical factor predisposing acute pancreatitis
[en] The decay of fluorescence on a range of commercially available papers was investigated by exposing them to a 1KW tungsten lamp for a total of 10 hours, with the samples removed for measurement at regular intervals. The results indicated that FWA decay is more rapid on papers with higher FWA efficacy. Only the papers with minimal FWA efficacy reached a plateau after which there was no further significant decay.
[en] Rarity of olfactory neuroblastoma makes it difficult for treating physician to practice with a consistent protocol. This study is performed to analyze our experience with various treatment modalities for patients with olfactory neuroblastoma. Discussion includes review of some recently published literatures. Between June of 1979 and April of 1997, 20 patients were treated under the diagnosis of olfactory neuroblastoma at Seoul National University Hospital. There were 14 male and 6 female patients. Age at initial treatment ranged from 13 to 77 years with median of 24 years. Fifteen of 20 patients had Kadish stage C. They were treated with various combinations of surgery, radiation therapy and chemotherapy; surgery+postoperative radiation therapy+adjuvant chemotherapy for 2 patients, surgery+postoperative radiation therapy for 6, neoadjuvant chemotherapy+surgery for 1, surgery+adjuvant chemotherapy for 1, surgery only for 2, neoadjuvant chemotherapy+radiation therapy for 3, radiation therapy+adjuvant chemotherapy for 1, radiation therapy only for 3, and no treatment for 1 patient. Follow-up ranged from 2 month to 204 months with mean of 39.6 months. The overall 5- and 10-year survival rates are 20% and 10%, respectably. Four patients are alive at the time of data analysis. One of four living patients was treated with radical surgery, postoperative radiation therapy and adjuvant chemotherapy, two patients with radical surgery and postoperative radiation therapy, and one with radical surgery only. Multidisciplinary approach, including radical surgery, pre- or post-operative radiation therapy and chemotherapy, should be addressed at the initial time of diagnosis. Although limited by small number of the patients, this study suggests importance of local treatment modality, especially radical surgery in the treatment of olfactory neuroblastoma
[en] Computed tomography (CT) was used for diagnosis of brain abscess in a 6-month-old, Japanese Black calf presented with neurological dysfunction, compulsive circling and vision disturbance. CT images showed asymmetric lateral ventricles, and presence of intra-cranial multiple low absorption lesions surrounded by capsule suggestive of abscess in the right cerebral hemisphere. Postmortem examination revealed marked swelling of right cerebral hemisphere and olfactory bulb. Multilocular large abscess containing creamy pus was found to occupy most area of periventricular and lateral ventricle. Fusobacterium necrophrum was isolated from the abscess contents as the causative agent. These results demonstrate that CT is useful tool for tentative diagnosis of bovine brain abscess