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Eosinophilic dermatosis of hematological malignancy is a paraneoplastic skin eruption associated with chronic lymphocytic leukemia and other B‐cell malignancies. It clinically resembles an insect bite reaction and it can precede the symptoms of the hematological malignancy or be related to a more aggressive course. Different treatments have been proposed, but partial response and recurrence are frequent. Herein, we describe a case of eosinophilic dermatosis associated with mantle cell lymphoma with remission after lenalidomide therapy.  相似文献   
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Pleomorphic xanthoastrocytomas (PXAs) are rare low-grade astrocytic tumors that typically present as superficial nodular cystic tumors of the cerebrum attached to the leptomeninx. Histologically, they are pleomorphic, hypercellular glial neoplasms. Despite the presence of microscopic pleomorphism, patients’ postoperative prognosis is generally good. Anaplastic PXAs (APXAs) have a high mitotic index and patients with APXAs have a worse prognosis than patients with PXAs. Here, we report an autopsy case of APXA initially diagnosed as PXA. After gross total resection, the tumor recurred and was diagnosed as an APXA; thereafter, the patient died. An autopsy revealed that the tumor had relapsed at the primary site and had spread to the leptomeningeal space while concurrently invading the cerebrum including the periventricular area forming multifocal lesions. The histological findings of the autopsy were similar to those for epithelioid glioblastoma (EGBM) and small cell glioblastoma (SCGBM). In particular, the periventricular area with multifocal lesions was composed of SCGBM-like cells. It has been shown that multifocal lesions are frequently identified in patients with SCGBM. This is the first histopathologically confirmed case of APXA-related tumor presenting with periventricular extension and multifocal lesion formation. The periventricular extension might be a feature of PXAs and APXAs. However, suspected periventricular spread on imaging in past cases of PXAs and APXAs might instead represent the malignant transformation of these tumors to glioblastoma-like high-grade tumors, which often show SCGBM-like histological patterns.  相似文献   
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We report our experience of a case with a malignant tumor of the mandible in which diagnostic imaging played an important role in the differential diagnosis and therapeutic strategy decisions. The patient was a 78-year-old woman who visited our hospital because of poor healing after tooth extraction. Multiple cytological diagnoses provided class II results, and a histopathological diagnosis of a biopsy also failed to show malignant findings. Therefore, a definitive diagnosis could not be made. Although the patient had a history of osteoporosis treatment, details of her medications were unclear. Therefore, bisphosphonate-related osteonecrosis of the jaw (BRONJ) could not be excluded, causing difficulty in management of the patient’s condition. Eventually, we mainly focused on the diagnostic imaging and planned the therapeutic strategy in accordance with treatment for a malignant tumor. A postoperative histopathological examination of the surgical specimen revealed squamous cell carcinoma. It is sometimes difficult to differentiate among atypical diseases such as malignant tumors of the mandible and BRONJ, based solely on clinical or diagnostic imaging results. However, in the present patient, diagnostic imaging suggested a malignant tumor, and the appropriate treatment could be selected.  相似文献   
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In order to clarify the influence of epinephrine in local anesthetics on endogenous epinephrine, we examined the concentration of plasma catecholamines (epinephrine and norepinephrine) and hemodynamics by administering 4 ml of 2% lidocaine containing different concentrations of epinephrine. Forty-three healthy adult male volunteers were divided into five groups according to epinephrine concentration: 0-µg (group I), 10-µg (group II), 20-µg (group III), 40-µg (group IV), and 50-µg (group V). The parameters were examined immediately, and at 1, 2, 3, 4, 5, 10, 15, and 20 min after the injection. In groups II, III, IV, and V, the plasma epinephrine concentration was elevated to peak at 5 min after the injection, after which it started to decline. The amount of increase in the plasma epinephrine concentration at 5 min showed a highly positive correlation with the amount of epinephrine added to the local anesthetic in groups II, III, and IV. In group V the plasma epinephrine concentration showed a marked increase as compared to the baseline level. Plasma norepinephrine concentrations were found to be significantly elevated at 15 and 20 min in group V. A decrease in systolic blood pressure was observed at 4 and 5 min in group II. A decrease in diastolic blood pressure was observed at 5 min in group II; at 3, 4, and 5 min in group IV; and at 2, 3, 4, and 5 min in group V. Heart rate revealed no significant differences from baseline level in any of the groups and there were no significant differences among the groups. It is suggested that exogenous epinephrine added to a local anesthetic may stimulate the presynaptic β2 receptors on sympathetic nerve endings and on the adrenomedulla, and accelerate the release of endogenous epinephrine.  相似文献   
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