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Discontinuation of medication is the treatment of choice for patients with chronic daily headache (CDH) who overuse their medications. This treatment may be difficult due to increased headache severity observed in patients immediately after withdrawal. We retrospectively evaluated the efficacy of valproic acid therapy in 66 patients with overuse of CDH medication during withdrawal therapy. Patients were all withdrawn from medications and valproic acid started at 250 mg or 500 mg daily. Forty-two (63.6%) patients had decreased headache severity, including 27.3% objective responses in the first week. At the last visit in the 12th week, 50 patients were headache-free and only one patient had persistent headache. Fifteen patients withdrew from therapy due to side effects and lost to follow-up within this timeframe. Thus, low dose valproic acid appears to be safe and effective in the management of withdrawal therapy.  相似文献   
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OBJECTIVE: The aim of the study was to examine the dose enhancement from scattered radiation at bone-dental implant interfaces during simulated head and neck radiotherapy. STUDY DESIGN: Four cylindrical titanium dental implants with 3 different sizes and lengths were implanted into a human mandible in 4 different positions. Ionization measurements for 6 MV X, 25 MV X, and Co-60 gamma rays were done. Thermoluminescent dosimeter (TLD 100 ) chips were used to measure radiation dose enhancement due to the scattered electrons from titanium and electronic disequilibrium at the tissue-metal interface. RESULTS: The results showed that for Co-60, there is a 21% maximum increase in dose to alveolar mandibular bone at the close proximity to the titanium. For 6-MV x-rays the dose enhancement increase was almost the same or slightly lower than for Co-60, while for 25-MV high-energy x-rays, dose enhancement was lower than that of others. This increase in dose enhancement fell off rapidly and became insignificant at 2 mm from the interface. CONCLUSION: Total dose that may lead to osteoradionecrosis risk of the mandible is slightly but not significantly affected by the scattered dose of the dental implants of lower jaw in the radiation field exposed to 3 different radiation beams.  相似文献   
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Asthma and allergic rhinitis are common problems in children and the causative pollen allergens vary according to the geographical area. The aim of this study was to investigate patterns of sensitization to common inhalant allergens, especially pollens, in Turkish children living in the Trakya region and to determine differences between rural and urban areas. Allergen skin testing was prospectively performed on 539 children aged between 4 and 17 years with respiratory allergy. The reaction was considered to be positive if the mean wheal diameter was at least 3 mm greater than that of the negative controls. We detected positive skin reactions in 420 (77.9%) children. Two hundred and eighty-one (52.1%) mite, 277 (51.4%) pollen, 174 (32.3%) mold, 65 (12.1%) animal dander, 12 (2.2%) cockroach and 6 (1.1%) latex skin sensitivities were detected. Among the pollen allergies 173 were cereal pollen (32.1%), 170 grass pollen (31.5%) and 144 tree pollen allergies (26.7%). The most common positive skin test among the pollens was to cultivated wheat (Titicum vulgare) (n = 116, 21,5%), followed by rye grass (Lolium perenne) and orchard grass (Dactylis glomerata). Positive skin reactions to Alternaria, to Candida albicans, and to all pollens except Ulmus competris, Pinus sylvetris, Platanus vulgaris and Tilia platyphyllos, were higher in children with allergic rhinitis than in those with asthma. In children from rural areas, allergic skin reactivity was found to be more common against Candida albicans, sheep dander and all pollens except Corylus avellana, Fraxinus excelsior, Populus alba, Pinus sylvetris, Platanus vulgaris and Chenopodium album, than in urban children. Although Trakya is close to Greece and other Mediterranean countries, this study suggests that the pollens, which sensitize children, are not similar.  相似文献   
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Experiments 1 and 2 address the controversy regarding the reliability of methamphetamine effects on interval timing. A temporal discrimination procedure was used, in which the rats were reinforced for pressing the left or the right levers after short and long signals, respectively. Methamphetamine (0.5 mg/kg sc) severely disrupted operant performance at 20-100 min after injection, which disabled the measurement of drug effects on temporal perception (Experiment 1). The same dose of methamphetamine shifted the psychometric function to the left at 100-180 min after injection, indicating an increase in subjective durations (Experiment 2). Although these results confirm the role of dopamine in interval timing, that a change in the speed of a neural clock mediates the methamphetamine-induced change in temporal perception is still a working hypothesis.  相似文献   
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Morphology of the lumbar spinal canal in normal adult Turks   总被引:2,自引:0,他引:2  
Pathological changes can occur in the diameters of the lumbar spinal canal. Therefore, assessing the canal size an important diagnostic procedure. Two hundred plain anterioposterior radiographs of the lumbar spine were examined. The sample consisted of 100 males and 100 females. The transverse diameter of the bony spinal canal (interpedicular distance), which was measured as the minimum distance between the medial surfaces of the pedicles of a given vertebra, was measured. In addition, the transverse diameter of the vertebral body, which was measured as the minimum distance across the waist of the vertebra, was measured. The distances were measured to the nearest one tenth of a millimetere using a Vernier caliper. At all levels (L1 - L5) the transverse diameters of the lumbar spinal canal were approximately 1 - 1.5 mm higher in males than in females. The intersegmental differences increased proximodistally, in both sexes. The ratio of the transverse diameter canal to the width of the vertebra ranged from 0.55 to 0.60 mm in both sexes. The distribution of the different lumbar canal types were 47% A, 42% B, 11% C. Additionally, subtypes were determined and classified.  相似文献   
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OBJECTIVE: The purpose of this study was to investigate the effects of exogenous local Insulin like growth factor-I (IGF-I) on the repair of full-thickness articular cartilage defects in immature rabbits. DESIGN: Thirty-six skeletally immature New Zealand rabbits between 6 and 8 weeks old were used. A single defect, 3.5-mm-wide by 4-mm-deep full-thickness articular cartilage defect in the medial femoral condyle, was created. The defect was either filled with a collagen sponge or with a collagen sponge impregnated with 5 mug of recombinant IGF-I. The animals were sacrificed at 4, 8 or 12 weeks, and the repair tissue was examined macroscopically and histologically. Repair tissue was also examined immunohistochemically for the presence of type-I collagen, type-II collagen and PCNA at all weeks. RESULTS: Newly formed tissue in all of the defects in the IGF-I group had the gross, histological and histochemical appearance of a smooth, intact hyaline articular cartilage. The average total scores on the histological grading scale were significantly better (p<0.05) for the defects treated with recombinant IGF-I at all time points. Immunostaining with an antibody against type-II collagen showed the diffuse presence of the repair cartilage in the IGF-I treated defects. The control groups demonstrated minimum staining with type-II collagen antibody. CONCLUSIONS: These findings suggest that repair of full-thickness immature cartilage defects can be enhanced by recombinant IGF-I.  相似文献   
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International Urology and Nephrology - To investigate the role of urinary neutrophil gelatinase-induced lipocalin (uNGAL) measurement in the early diagnosis of acute kidney injury that may occur...  相似文献   
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A 19-year-old female on chronic peritoneal dialysis developed acute peritonitis; multiple peritoneal fluid and catheter tip cultures yielded Penicillium species. She promptly responded to catheter removal and intravenous amphotericin B, followed by oral fluconazole, without further recurrences 1 year later. This is the first reported case of Penicillium peritonitis in the pediatric population. We review the microbiology and clinical spectrum of this disease, as well as the few previous reported cases in adults. Received: 2 November 1998 / Revised: 1 February 1999 / Accepted: 4 February 1999  相似文献   
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