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11.
Local and regional recurrences are frequent problems in breast cancer management. Radiation therapy is effective in producing long term remission. This study evaluates the results of radiation therapy of 215 patients with recurrent disease limited to the chest wall and/or regional lymph node areas. The local results showed complete control in 67% of cases (mean and median durations 32 months and 22 months, respectively), partial control in 24% of cases (mean and median 11 and 8 months, respectively) and no control in the remaining 9%. The radiation dose recommended for the treatment of recurrent mammary carcinoma is 5000 rads in 5 weeks for relatively small lesions. Supplementary local doses of 500-1000 rads in 1 week may be given to bulky lesions as necessary for residual disease. Although local relapse indicates a poor prognosis, it is by no means totally hopeless. Of 215 patients treated 44 (21%) survived 5 years and 10 (5%) survived 10 years following radiation therapy of recurrent disease. There were seven patients, or 3%, who were free of cancer at 5 to 15 years. Radiation therapy was valuable in controlling local lesions, and thus, in improving quality of survival, even in those patients who eventually died of metastatic disease.  相似文献   
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Acute, exsanguinating hemorrhagic cystitis secondary to cyclophosphamide therapy, radiation therapy, or an infiltrating bladder tumor may be managed successfully with intravesical Formalin therapy. The indications for its use, the technique, success rates, and complications are discussed. This treatment was effective in 14 of 16 patients in the present series and 79 of 90 cases reported in the literature. Dilutions of 4% or less were as effective as a 10% dilution and were associated with far fewer complications. The early use of Formalin in the treatment of intractable hemorrhagic cystitis is recommended.  相似文献   
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The main purpose of this research was design and development of an intelligent system based on combined fuzzy logic and machine vision techniques for grading of egg using parameters such as defects and size of eggs. The detected defects were internal blood spots, cracks and breakages of eggshell. The Hue-Saturation-Value (HSV) color space was found useful in obtaining visual features during Image Processing (IP) stage. The fuzzy inference system (FIS) was designed based on triangular and trapezoidal membership functions, fuzzy rules with logical operator of AND inference system of Mamdani and method of center average for defuzzifier. The evaluation results of IP algorithms showed that use of IP technique has good performance for defects and size detection. The Correct Classification rate (CCR) was 95% for size detection, 94.5% for crack detection and 98% for breakage detection. The overall accuracy FIS model in grading of the eggs was 95.4.  相似文献   
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In this paper, the size-dependent vibrational behavior of a microbeam conveying fluid was investigated using the Modified Couple Stress Theory. For cantilever and clamped-clamped microbeams, the small amplitude vibration equation of the micro-beams was solved using a Galerkin based reduced order model and the effects of material length-scale parameter on its natural frequencies were evaluated. It was found that for the both cantilever and clamped-clamped conditions, the critical fluid velocities predicted by the modified couple stress theory are higher than those predicted by the classical beam theory. In addition, the differences between the eigen-frequencies and the critical fluid velocities predicted by the modified couple stress theory and classical beam theory depends on the ratio of the material length-scale parameter to the beam height. In addition an unexpected result in the difference between the first eigen-frequency of the cantilever micro-beam obtained by the classical and the modified couple stress theory has been achieved.  相似文献   
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High diagnostic sensitivity and specificity while maintaining the least dose to the patient is the ideal mammography. The objective of this work was to evaluate patient dose and image quality of mammograms to propose corrective actions. The image quality for 1242 patient in 7 mammography facilities in Tehran city was evaluated based on selected image quality criteria using a three-point scale. Clinical image quality, the entrance surface air kerma, the average glandular dose and optical density of films for standard PMMA phantom of 4.5 cm thickness were evaluated. The results showed that up to 72 % of mammograms were in good condition to be diagnosed, and only about 3.4 % of the images were unacceptable or with suboptimal quality. The entrance surface air kerma values were in the range of 3.8-10.5 mGy, average glandular dose 0.5-1.8 mGy and optical density of films 0.74-2.03. The image quality evaluation after correction actions, periodic image quality evaluation and using the correct equipment certainly will improve patient dose.  相似文献   
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This paper presents a thermoeconomic optimization of a shell and tube condenser, based on two new optimization methods, namely genetic and particle swarm (PS) algorithms. The procedure is selected to find the optimal total cost including investment and operation cost of the condenser. Initial cost includes condenser surface area and operational cost includes pump output power to overcome the pressure loss. Design parameters are tube number, number of tube pass, inlet and outlet tube diameters, tube pitch ratio and tube arrangements (30, 45, 60 and 90°). Therefore, shell diameter should be selected less than 7 m, tube length should be less than 15 m, and ratio of diameter to tube length should be in the range of 1/12 to 1/3. In addition, it is found that GA provides better results for computer CPU running time, compared to PS algorithm. Finally, a sensitivity analysis of design parameters at the optimal point is conducted. Results show that an increase in the tube number leads to decrease in the objective function first then it leads to a considerable increment in objective function.  相似文献   
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