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This paper presents a method of improving the TLD-100 dose reassessment performance. This method consists of applying numerical analysis techniques for evaluating the TLD-100 phototransferred thermoluminescence (PTTL) glow curve. From this analysis, a simple procedure for estimating the ultraviolet background components usually present in phototransferred thermoluminescence (TL) signals has been established. This procedure has been implemented in a computer program which performs the automatic evaluation of the glow curves and extracts the dose information contained in the PTTL curves. The use of this computer-aided evaluational method has enabled the extension of the working range of estimated absorbed dose down to 0.2-0.5 mGy with very adequate operational quality for doses even below the conventionally admitted lower reestimation limit (approximately 2 mGy). Because TL readout is a destructive process, the ability to reestimate doses can be important in any kind of dosimetric activity, such as operational dosimetry programs. The other commonly used dosimeter, film, uses a nondestructive readout and, therefore, presents some advantages over TLD when dose reassessment is necessary. With the reported improvements in the TLD-100 dose reassessment performance, the full range of absorbed doses covered by film dosimetry can now be reliably reassessed using TLD-100 dosimeters.  相似文献   
43.
BACKGROUND: Pemphigus vulgaris (PV) is a severe blistering disease involving the skin and mucous membranes. The most common causes of death in these patients are adverse effects of drugs, and infection. Skin lesions are one of the important sources of infection. Thus, any local treatment that could reduce healing time of lesions and consequently reduce the total dosage of drugs needed to treat is favourable. OBJECTIVE: To evaluate the efficacy of epidermal growth factor (EGF) in reducing healing time of lesions in patients with pemphigus vulgaris. METHODS: In this randomized, double-blind, within-patient, left/right, controlled trial, 20 hospitalized patients with pathologial and immunohistologial (direct and indirect immunoflourecence) proven pemphigus vulgaris (PV) were chosen. In addition, all patients had at least one appropriate pemphigus lesion on each side of the body that had not healed after 2-week systemic therapy and sterile saline washing. EGF (10 microg/g) in 0.1% silver sulfadiazine cream vs. 0.1% silver sulfadiazine cream alone was applied randomly on one side of the body. RESULTS: Kaplan-Meier survival analysis suggested that median time to heal with application of EGF plus silver sulfadiazine cream was 9 days, in comparison with 15 days for silver sulfadiazine cream alone (log-rank test, P=0.0003). No intervention-related adverse effect was observed during the study. CONCLUSIONS: EGF can significantly reduce healing time of skin lesions in patients with pemphigus vulgaris, at least when this cream base is applied (Cochrane skin group identifier: CSG20).  相似文献   
44.
Treatment of chronic osteomyelitis of distal tibia is complex. It often requires the association of antibiotic therapy and a surgical procedure. This consists of exhaustive debridement of infected bone and soft tissue which must have adequate cutaneous coverage and vascular supply which enables creating a barrier to microorganisms and greater resistance to infection. Free or pedicled muscular flaps have been the techniques most often used for this type of lesions. Free flaps require a precise microsurgical technique and prolonged surgery. Pedicled muscular flaps do not provide sufficient coverage and vascularisation of the distal tibia for large size defects. The fasciocutaneous flap has been used for the treatment of coverage defects in the perimalleolar area and the heel. We report the utility of this flap as management of chronic osteomyelitis of the distal third of the tibia with complete healing of the infection and correct cutaneous coverage without complications.  相似文献   
45.

Objectives  

This study was designed to assess the prevalence of adverse drug reactions (ADRs) in the internal medicine wards of two teaching Hospitals, identify the most common ADRs, the principal medications involved, and determine the risk factors implicated in the occurrence of such ADRs.  相似文献   
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To compare the diagnostic and prognostic usefulness of symptom-limited versus load-limited submaximal stress testing, 76 patients, during the first week post acute non-complicated myocardial infarction, were submitted to a symptom-limited Naughton-modified protocol stress test. At 2 METs, 3 METs and maximal effort levels, the tests were classified as positive or negative following the currently used criteria. After a mean follow-up of 15 months, the symptom-limited protocol showed the best sensitivity (95%), specificity (78%), positive (64%) and negative (98%) predictive value, and also the highest risk ratio (27.4) for prediction of subsequent coronary events (2p less than 0.01 vs 2 METs, 3 METs and 2D-Echocardiogram results). Forward stepped multiple correlation analysis indicated independent prognostic value for the results of the symptom-limited stress test (R2: .52 p less than 0.01) and for the location of the myocardial infarction (R2: .05 p less than 0.05) only. In addition, the discriminant prognostic power of the symptom-limited protocol was significant after the fourth month of follow-up (2p less than 0.05 vs submaximal tests and 2D-Echo). Therefore, we recommend the performance of a symptom-limited stress test during the first week post acute non-complicated myocardial infarction, provided that all coronary active medication has been withheld 24 hours before the test.  相似文献   
48.
Purpose: To verify the efficacy of ultrasound (US)-guided injection of large amounts of ethanol into large or multiple liver lesions, in a single session under general anesthesia (one-shot PEI) for percutaneous ablation of hepatic tumors. Methods: Twenty-nine patients (27 with 51 hepatocellular carcinoma (HCC) nodules on cirrhosis, diameter range 1.0<+>–<+>9.0 cm; two patients with a single metastasis from the gastroenteric tract, 5.0 and 9.0 cm, respectively, in diameter) were treated with one-shot PEI. Results: The total volume of alcohol delivered per patient ranged from 16 to 210 ml. Mean ethanol volume in all patients was 49 ml. Dynamic computed tomography (CT) examination showed complete necrosis in 41 of 50 lesions. Two patients died of hypovolemic shock due to massive upper gastrointestinal bleeding, 3 and 7 days, respectively, after the interventional procedure. All the remaining patients are alive (follow-up 5<+>–<+>14 months) except one who died of liver failure 5 months after. New HCC nodules occurred in six patients within 6 months and one intralesional relapse was recorded. Conclusion: In this preliminary experience, one-shot PEI is as effective in inducing liver tumor necrosis as traditional PEI; its advantages are shorter treatment time and the capability of treating larger and multiple liver lesions.  相似文献   
49.
21 patients, whose age ranged from 17 to 60 years and who had not been previously treated with antibiotics or other drugs, received bacampicillin as a perioperative prophylaxis for minor operations in the oral cavity. Four oral doses of bacampicillin were administered: each dose of 800 mg every 12 h, and the last dose was administered 2 h before surgery. To assess bacampicillin serum concentrations two blood samples were collected from each patient: the first sample was obtained 1 h before surgery and the second one during surgery. Together with the second blood sample, small quantities of gingiva and bone were obtained from each patient to also assess the antibiotic concentrations in these tissues (microbiological method). The results show that bacampicillin reaches high concentrations in both the blood and tissues studied by us, and that a direct correspondence exists between blood and gingival and bone tissue concentrations. Furthermore, it should be noted that no postoperative infections developed in our patients. These results lead to the conclusion that bacampicillin appears to be a suitable drug in the therapy of dental infections.  相似文献   
50.
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