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A 54-year-old man presented with an 8-year history of a hard asymptomatic mass of the left submandibular area. Total excision of the left submandibular gland with radical neck dissection was performed under a diagnosis of a submandibular tumor, probably a malignant mixed tumor. The pathologic diagnosis was carcinosarcoma consisting of carcinomatous and sarcomatous elements. The epithelial component was composed of squamous cell carcinoma, undifferentiated carcinoma, and adenocarcinoma. The nonepithelial component was composed of chondrosarcoma, osteosarcoma, spindle cell sarcoma, rhabdomyosarcoma, and liposarcoma. In the central area of the tumor, a few remnants of benign pleomorphic adenoma were identifiable. The finding suggested that in our patient, the carcinosarcoma arose from a preexisting pleomorphic adenoma. In view of the expected aggressive nature of the tumor, the patient was treated with postoperative radiotherapy of 60 Gy total, in 30 daily fractions of 2 Gy, and chemotherapy. He currently remains well and free of disease 24 months after treatment.  相似文献   
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The medial globus pallidus plays a crucial role in generation of L‐DOPA‐induced dyskinesia in patients with Parkinson's disease. The 6‐hydroxydopamine‐lesioned rat exhibiting behavioral sensitization to L‐DOPA is one useful animal model for examining L‐DOPA‐induced dyskinesia. To determine neuropathological abnormality responsible for behavioral sensitization, the medial globus pallidus and the substantia nigra reticulata in 6‐hydroxydopamine‐lesioned rats treated with L‐DOPA were examined. Intermittent L‐DOPA treatment induced hypertrophy of the lesioned‐side of medial globus pallidus and substantia nigra reticulata of 6‐hydroxydopamine‐lesioned rats with behavioral sensitization to L‐DOPA. Additionally, coadministration of a 5‐HT1A receptor agonist, 8‐hydroxy‐2(di‐n‐propylamino)tetralin with L‐DOPA, alleviated the hypertrophy with improvement of the behavioral sensitization. These results suggest that hypertrophy of the medial globus pallidus and substantia nigra reticulata is associated with induction of behavioral sensitization to L‐DOPA in 6‐hydroxydopamine‐lesioned rats. Therefore, neuropathological changes corresponding to hypertrophy might underlie L‐DOPA‐induced dyskinesia in patients with Parkinson's disease.  相似文献   
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A case of pulmonary varices in a 73-year-old female is presented. Routine chest X-ray revealed a mass in the right hilar region. CR tomogram showed a round, clearly defined mass at the right hilum. Computed tomography demonstrated marked enlargement of the proximal portion of the pulmonary vein at the entrance of the left atrium, which was suspected to be pulmonary varices. The diagnosis was confirmed by pulmonary angiography. During the arterial phase no abnormal findings were seen, but during the venous phase the veins of the right upper and middle lobes were found to be draining into the dilated pulmonary vein and then into the left atrium. Thus, the diagnosis of pulmonary varices was established. CT and angiography are the most useful methods for definitive diagnosis of pulmonary varices.  相似文献   
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A simplified technique of the liver transplantation under hypothermia has been studied in dog. An immersion hypothermia was used in both the donor and the recipient. The temperature of the graft at excision was lowered to 20 degrees C with supplemental use of topical cooling. The temperature of the recipient was lowered at 27 degrees C when the transplantation was attempted. Chlorpromazine and dopamine were employed beneficially in hypothermia. No perfusion or irrigation of the graft was performed. The use of heparin was avoided. Anastomoses were carried out in turn of the proximal vena cava, portal vein, distal vena cava and the hepatic artery with a stem shaped aorta. Reperfusion was established after the completion of anastomosis between the proximal vena cava and portal vein. The anhepatic phase of the recipient was uneventfully lasted without heparinization. All dogs, 5 out of 11 without early surgical troubles survived more than 5 days. Immunosuppressive therapy was not employed except one which died of pneumonia on the 19th postoperative day. Histologically, these dogs were free from ischemic injury and/or thrombotic lesion throughout transplantation procedure.  相似文献   
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Various 7 beta-[2-(2-aminothiazol-4-yl)-2-substituted acetamido]-3-vinyl-3-cephem-4-carboxylic acid derivatives (Ia--e, IIa--g) were synthesized in order to find a new orally active cephalosporin improving the antibacterial activity of cefixime (CFIX) against Staphylococcus aureus. These derivatives include three types of alpha-substituted 2-(2-aminothiazol-4-yl)acetyl side chain; i) mono or non substituted acetyl moiety, ii) carboxyalkoxyimino acetyl moiety, iii) phosphonomethoxyimino and hydroxyimino acetyl moiety. Their structure-activity relationships and urinary recoveries in rats were studied. As a result, the compound with a hydroxyimino acetyl side chain (IIg, FK482) showed good oral absorption and excellent antibacterial activity against both gram-positive and gram-negative bacteria and was selected as a candidate for clinical trial.  相似文献   
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