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Thermal therapy, Part III: ablation techniques   总被引:2,自引:0,他引:2  
Ablative treatments are gaining increasing attention as an alternative to standard surgical therapies, especially for patients with contraindication or those who refuse open surgery. Thermal ablation is used in clinical applications mainly for treating heart arrhythmias, benign prostate hyperplasia, and nonoperable liver tumors; there is also increasing application to other organ sites, including the kidney, lung, and brain. Potential benefits of thermal ablation include reduced morbidity and mortality in comparison with standard surgical resection and the ability to treat nonsurgical patients. The purpose of this review is to outline and discuss the engineering principles and biological responses by which thermal ablation techniques can provide elevation of temperature in organs within the human body. Because of the individual problems associated with each type of treatment, a wide range of ablation techniques have evolved including cryoablation as well as ultrasound, radiofrequency (RF), microwave, and laser ablation. Aspects of each ablation technique, including mechanisms of action, equipment required, selection of eligible patients, treatment techniques, and patient outcomes are presented, along with a discussion of limitations of the techniques and future research directions.  相似文献   
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In the present study, we have synthesized mixed cuprous/copper oxide nanosuspensions by metallosurfactant based microemulsion technique. Three metallosurfactants were synthesized which includes two non-ionic double chained metallosurfactants with C12, C16 chains with coordinated copper i.e. Cudda and Cuhexa, respectively. Another cationic double chained metallosurfactant with loosely bound metal (Cuctac) was also prepared. The prepared metallocomplexes were characterized using FTIR, elemental analysis, and NMR. The effect of the position of metallosurfactant in microemulsion on the fabrication and properties of nanosuspensions was elucidated. In this method, no external reducing agent and capping agent were added and tween 80 acted both as reducing and stabilizing agent for the nanoparticles. The synthesized nanoparticles were characterized and it was observed that mixed copper and cuprous oxide particles are present in colloidal suspension for all the three studied metallosurfactants. The kinetics of formation of mixed copper/cuprous oxide nanosuspensions (Ns) and their stability was estimated using Uv-visible spectroscopy. Further, the binding and interactions of copper nanosuspensions with calf Thymus DNA (CT-DNA) were assessed using Uv–vis spectroscopy, circular dichroism and gel electrophoresis. Additionally, the antioxidant activity of the Cu Ns was checked using DPPH assay. The role of positive charge on nanoparticles as evaluated from Zeta potential was responsible for DNA affinity. The DNA conformational changes in the presence of nanosuspensions and relevant scavengers were investigated. Further, the anti-proliferative activity of copper Ns was assessed using HeLa cells and Cuhexa derived Ns were proved to be active with highest activity at a low concentration and were nontoxic towards normal cell lines. In summary, this work demonstrates a softer approach for the synthesis of copper nanosuspensions with a size range of 2–5?nm and evaluated the role of type and structure of metallosurfactant on size, stability of particles and anti-proliferative activity.  相似文献   
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AIM: The purpose of this article is to report a rare case of primary tuberculosis of the tongue. BACKGROUND: Tuberculosis is an infectious, chronic granulomatous disease that can involve almost any organ in the body, but primary lesions are usually confined to the lungs. Oral lesions are an infrequent occurrence in tuberculosis, and tuberculosis of the oral cavity is often a consequence of active pulmonary tuberculosis. Although primary tuberculosis in the oral cavity has been documented, it is a rare occurrence. REPORT: A 42-year-old male patient presented with chief complaints of severe pain and ulceration on the ventrolateral surface of the left side of the tongue, measuring about 1.25 x 1.50 cm with surrounding erythema and induration of one-month duration. The ulcer was initially painless but became painful later with increased severity over time. The sore tongue caused difficulty in eating, drinking, swallowing, and even talking. The patient also complained of malaise for some duration, but there was no history of fever, cough, weight loss, and his bladder-bowel habits were normal. An excisional biopsy differentiated the lesion from squamous cell carcinoma and confirmed the diagnosis. SUMMARY: Even though primary tuberculosis in the oral cavity is a rare finding, it must be included in the differential diagnosis of mucosal lesions. This case provides a clinical example of the importance of this inclusion for the well being of the patient and for the community due to the communicable nature of the disease.  相似文献   
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European Journal of Orthopaedic Surgery & Traumatology - The purpose of this study is to evaluate any association between preoperative smoking and perioperative and early postoperative...  相似文献   
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Surgery Today - Esophageal cancer surgery, comprising esophagectomy with radical lymphadenectomy, is a complex procedure associated with considerable morbidity and mortality. The enhanced recovery...  相似文献   
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