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51.
Basal cell carcinoma is the most common skin malignancy and is found in skin exposed to the sun. It is rarely seen bilaterally in ears, ankles or breasts. There has been no literature about bilateral basal cell carcinoma of lower eyelids symmetrically. A 68-year-old male patient had been suffering from two lesions on his lower eyelids for two years. The first lesion appeared on the right lower eyelid two years ago and got larger. Then the second lesion occurred on the left lower eyelid a year and a half ago. The patient had worked as a farmer for fifteen years. Physical examination revealed ulcerated lesions, with surrounding hyperemia, 12 x 6 mm in size, on both lower eyelids. Both lesions were excised and repaired with lateral malar flap+mucosal graft. One year later, there no evidence of recurrence, and postoperative scars were functionally and cosmetically acceptable. We present a case of bilateral basal cell carcinoma involving both lower eyelids symmetrically, reviewing the literature.  相似文献   
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For hyperthermia treatment planning, dielectric properties of several tissue types are required. Since it is difficult to perform patient specific dielectric imaging, default values based on literature data are used. However, these show a large spread (50%). Consequently, it is important to know what limit this spread imposes on the accuracy of the SAR and subsequently on the temperature distributions. Hyperthermia treatment plans performed with different values for the dielectric properties were compared. This showed that a spread of 50% resulted in the average absolute difference of 20% in both SAR and temperature distributions (heat sink approach) for regional hyperthermia. For interstitial hyperthermia, a spread of 25% resulted in the averaged absolute difference of 10% in the SAR distributions and 5% in the temperature distributions (heat sink approach). Considering other problems that hamper hyperthermia treatment planning, it can be concluded that default values for the dielectric properties suffice.  相似文献   
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Development of a regional hyperthermia treatment planning system.   总被引:1,自引:0,他引:1  
A flexible and fast regional hyperthermia treatment planning system for the Coaxial TEM System has been devised and is presented. Using Hounsfield Unit based thresholding and manually outlining of the tumour, a 40 cm CT data set (slice thickness 5 mm) is segmented and down scaled to a resolution of 1 cm, requiring only 30 min. The SAR model is based on the finite-difference time-domain (FDTD) method. The number of time steps to achieve numerical stability has been determined and was found to be 7000. Various optimizations of the SAR model have been applied, resulting in a relatively short computation time of 3.7 h (memory requirements 121 MB) on a Pentium III, 450 MHz standard personal computer, running GNU/Linux. The model has been validated using absolute value(Ez) measurements in a standard phantom inserted in the Coaxial TEM Applicator under different conditions and a good agreement was found. Hyperthermia treatment planning in combination with the homemade visualization tools have provided much insight in the regional hyperthermia treatment with the Coaxial TEM Applicator.  相似文献   
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The comet assay, one of the most widely used techniques for the evaluation and detection of DNA strand breaks, is frequently employed in vivo. In vitro assays are usually performed with mammalian cell lines, clearly not the best choice for tests on aquatic genotoxicity. Here we evaluated a fish hepatoma cell line (RTH-149) and a primary blood cell culture from the intertidal colonial tunicate Botryllus schlosseri as possible model targets for comet assays using the genotoxic agent H2O2. We found that DNA strand break levels in RTH-149 fitted dose-dependent responses better than the tunicate cells. Moreover, in B. schlosseri controls, 34% of the cells were already ranked as severely damaged. Assays were then performed on water samples from the polluted Kishon river (Israel) on three different dates, using RTH-149 cells (50% dilutions, 2-h exposures). In all cases, high genotoxicity of the river water was revealed by evaluating comet percentages, average tail lengths and DNA damage levels. This assay was found to be fast and sensitive, appropriate to be employed as a part of a monitoring program. The use of B. schlosseri blood cells should be validated in additional work.  相似文献   
57.
OBJECTIVE: To assess the utility of the D-dimer test-a widely available, less costly, and less time-consuming test than others used to diagnose or exclude deep vein thrombosis (DVT) and pulmonary embolism. DESIGN: Blind comparison. SETTING: An inpatient rehabilitation facility in Turkey. PARTICIPANTS: Sixty-eight consecutive inpatients being rehabilitated after stroke, spinal cord injury, hip arthroplasty, or traumatic brain injury. INTERVENTIONS: A latex D-dimer assay was performed on each patient at admission and then weekly throughout the hospital stay. Color Doppler ultrasonography of the lower limbs was also done for each patient at admission and was repeated when indicated by clinical signs and symptoms of DVT or by elevated D-dimer levels.Main outcome measures Patients' clinical findings, D-dimer test results, and ultrasonography results were recorded. Sensitivity, specificity, and positive and negative predictive values were calculated for the D-dimer test, each clinical finding, and combinations of D-dimer results and clinical findings in relation to DVT diagnosis. RESULTS: The sensitivity and negative predictive value of the D-dimer test were high, at 95.2% and 96.2%, respectively. The specificity and positive predictive value were low, at 55.3% and 48.7%, respectively. No single clinical finding was reliably diagnostic for DVT. CONCLUSIONS: The D-dimer assay is a reliable method for ruling out DVT. In the rehabilitation setting, it can be used as a routine screening test or to assess cases of suspected DVT. D-dimer testing may reduce the need for sophisticated, time-consuming, and expensive diagnostic workup of rehabilitation inpatients, a group that is at increased risk for DVT.  相似文献   
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Previous studies have investigated whether physical activity increases serotonin hormone levels. Serotonin receptor dysfunction is one of the frequently accused factors of premature ejaculation (PE). Nevertheless, no studies up to date have demonstrated that the association between physical activity and premature ejaculation. We aimed to investigate the relationship between physical activity and PE and determine whether moderate physical activity might delay ejaculation time or be an alternative treatment for PE. A total of 105 patients diagnosed with PE were enrolled in this study. Of the patients, 35 were treated with dapoxetine, (30 mg) on demand (Group 1), 35 performed moderate physical activities (Group 2), and 35 performed minimal physical activity (Group 3‐sham). Demographic characteristics, metabolic equivalents (MET), premature ejaculation diagnostic tool (PEDT) and intravaginal ejaculatory latency time (IELT) were recorded. There were no significant differences among three groups in terms of age, BMI, MET, PEDT or IELT before treatment. At the end of the study, there was significant decrease in PEDT scores, and increase in IELT in groups 1 and 2 as compared to Group 3. In conclusion, a moderate physical activity longer than 30 min at least 5 times a week leads to ejaculation delay, and appears as an alternative to dapoxetine on demand for the treatment of PE.  相似文献   
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