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Papillary and follicular carcinoma represent almost 90% of the thyroid malignancies, being responsible for 70% of the mortality generated by thyroid cancer. Lymph node involvement, far more significant in the papillary form, increases the risk of local recurrence and affects long-term survival. Due to the lack of prospective randomised studies to assess the benefit of lymph node dissection in addition to total thyroidectomy, there is no consensus regarding the need of routine vs elective central compartment lymphadenectomy. Routine lymph node dissection of the central compartment is supported by the argument that it reduces the amount of neoplastic thyroid tissue and, therefore, optimises the effectiveness of radioiodine in DTC patients. Moreover, it provides an accurate staging by the detailed histopathological analysis and allows an optimal postoperative thyroid scanning. No additional morbidity of central lymphadenectomy is reported, compared to total thyroidectomy alone, if performed by a specialised surgeon. However, reinterventions for recurrence in the central compartment, carry a significantly higher risk of recurrent nerve and parathyroids damage. Unlike central compartment, it is generally agreed that lymphadenectomy of the lateral neck, as modified radical neck dissection, is employed when there is evidence of neoplastic lymph node involvement, wether macroscopic, imaging or by pathological data.  相似文献   
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Nicorandil (N-(2-hydroxy-ethyl)-nicotine amide nitrate), drug recently introduced in therapy, is used as a vasodilator through potassium channel activation. Nicorandil is obtained by treating nicotinic acid chloride hydrochloride with nitro-oxy-ethyl-amine nitrate in an organic solvent. The authors suggest a method that uses ethyl nicotinate as raw material. Thus, the drug can be obtained from indigenous raw materials, at a lower price than the imported ones, with a high purity and a good yield.  相似文献   
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The most common clinical presentation of differentiated thyroid cancer (DTC), consisting of papillary and follicular adenocarcinoma (with their histological variants), is the solitary thyroid nodule. A review of the literature is performed in order to describe particular forms of DTC, in terms of incidence, diagnosis and treatment: occult carcinoma, carcinoma on aberrant thyroid tissue, "functional" thyroid carcinoma and familial non-medullary carcinoma. A particular interest is shown to the coexistence of malignancy with benign thyroid diseases, such as goiter, hyperthyroidism and Hashimoto's thyroiditis, as well as parathyroid adenoma. In conclusion, the authors emphasize that the association of carcinoma with benign thyroid conditions is not rare and it substantiate an aggressive approach in regard to diagnosis and treatment, increasing the indication for surgery and, moreover, for total thyroidectomy.  相似文献   
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To assess the dosimetric effect of using interpolated contours in planning intensity‐modulated radiation therapy (IMRT) for advanced T‐stage nasopharyngeal carcinoma. The present study focused on T3–T4 tumours where the proximity of targets to neurological organs poses a stringent test on the feasibility of such an approach. Contours of targets and organs were delineated on CT images of 2.5‐mm interval and a reference IMRT plan was generated. An investigative (INV) IMRT plan was then generated with the same planning protocol, but based on interpolated contours that replaced deleted contours on alternate slices. The reference and INV plans were compared. Regarding target coverage, all targets in the INV plans met the acceptance criteria except for the PTV in one case. Regarding organs, the mean dose to 1% volume of the brainstem and spinal cord in the INV plans were kept below their dose limits. No significant differences in the mean doses to others organs were found. Satisfactory target coverage and protection of critical organs to a degree similar to full‐scale contouring could be achieved with use of interpolated contours. The saving in manpower time for contouring is expected to significantly improve the throughput of the IMRT planning process.  相似文献   
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The folic acid antagonist, methotrexate, has many applications in the treatment of neoplastic disease. While methotrexate produces several well-recognized toxic effects, cutaneous reactions are rare. A patient who developed classical erythema multiforme while receiving low-dose methotrexate as treatment of nonmetastatic gestational trophoblastic neoplasia is presented. Erythema multiforme has been associated with a variety of pharmacologic agents. It typically presents as a pruritic papular dermatitis of the extensor surfaces of the extremities and may require multiple skin biopsies to establish the diagnosis. Spontaneous reversal usually occurs with discontinuation of therapy. Patients developing erythema multiforme related to antineoplastic agents should be switched to an alternate regimen.  相似文献   
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An enquiry into sudden infant death syndrome (SIDS) in 1987 furnished us with detailed epidemiological data for 281 cases that underwent a thorough post-mortem examination. This analysis uses these data to evaluate the role the autopsy plays in explaining sudden death. The cases were classified into three diagnostic groups: explained causes of death (group 1), unexplained deaths with anomalies (group 2), and no anomaly (group 3). These 281 cases show the three essential features that characterize SIDS: over-representation of males, increased deaths during the second and third months of life, and increased deaths during winter. The autopsy examination revealed that many of these deaths had a medical explanation. Almost half were assigned to group 1. At the time of autopsy, no precise pathology could be diagnosed for 147 deaths; of these, 140 showed histological anomalies. There were only seven sudden deaths for which no abnormal sign was evident at the autopsy. These results are compared with those of similar studies and discussed in connection with three factors: the initial selection of cases, the nature and degree of the investigations, and the possible interpretations of the symptoms uncovered.  相似文献   
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