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21.
From two types of class V act mutants of Streptomyces coelicolor two monomeric precursors of actinorhodin have been isolated and their structures determined. One is the known antibiotic kalafungin and the other a new compound. Their relationship to actinorhodin biosynthesis is discussed.  相似文献   
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Triptolide is potent immunosuppressive has been reported to inhibit autoimmunity, compound isolated from Chinese herbal medicine. Triptolide allograft attributed to the suppression of T cells via NF - kB rejection and GVHD, and its efficacy was previously pathway and apoptosis. In the present study, we detailedly analyzed Triptolide' s function on murine primary T cell. We found that Triptolide could inhibit T cell activation and proliferation by dramatically down - regulating cell division and cell cycle. Triptolide inhibited T cell activation in a dose- dependent manner, and the inhibition was mediated by both NF- kB pathway and AP - 1 pathway.  相似文献   
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A case of early gastric carcinoma accompanied by Dieulafoy ulcer is presented. The patient, a 26‐year‐old female, visited our emergency room with chief complaints of massive hematemesis and tarry stool. The initial endoscopic examination revealed a superficial depressed lesion with a faded color accompanied by a tiny ulcer with converging folds at the anterior wall of the middle gastric body. Although no active bleeding vessel was found at that time, the patient was admitted to our hospital for further check‐ups and treatment. On the 6th hospital day, she developed massive hematemesis resulting in shock. Urgent endoscopy, this time, disclosed an exposed bleeding vessel at the small ulcer floor previously mentioned, and endoscopic hemostasis was achieved. Since, however, a biopsy at initial examination from the surrounding depressed area proved carcinoma, a partial distal gastrectomy was subsequently carried out. Histological examination of the resected specimen confirmed the diagnosis of carcinoma limited to the mucosa and submucosa along with findings consistent with Dieulafoy ulcer. This is a rare case of combination of early cancer and Dieulafoy ulcer particularly in such a young patient. A review of the literature is also presented.  相似文献   
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OBJECTIVE: To investigate the serial CT findings of Paragonimus westermani infected dogs and the microscopic structures of the worm cysts using Micro-CT. MATERIALS AND METHODS: This study was approved by the committee on animal research at our institution. Fifteen dogs infected with P. westermani underwent serial contrast-enhanced CT scans at pre-infection, after 10 days of infection, and monthly thereafter until six months for determining the radiologic-pathologic correlation. Three dogs (one dog each time) were sacrificed at 1, 3 and 6 months, respectively. After fixation of the lungs, both multi-detector CT and Micro-CT were performed for examining the worm cysts. RESULTS: The initial findings were pleural effusion and/or subpleural ground-glass opacities or linear opacities at day 10. At day 30, subpleural and peribronchial nodules appeared with hydropneumothorax and abdominal or chest wall air bubbles. Cavitary change and bronchial dilatation began to be seen on CT scan at day 30 and this was mostly seen together with mediastinal lymphadenopathy at day 60. Thereafter, subpleural ground-glass opacities and nodules with or without cavitary changes were persistently observed until day 180. After cavitary change of the nodules, the migratory features of the subpleural or peribronchial nodules were seen on all the serial CT scans. Micro-CT showed that the cyst wall contained dilated interconnected tubular structures, which had communications with the cavity and the adjacent distal bronchus. CONCLUSION: The CT findings of paragonimiasis depend on the migratory stage of the worms. The worm cyst can have numerous interconnected tubular channels within its own wall and these channels have connections with the cavity and the adjacent distal bronchus.  相似文献   
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OBJECTIVE: We sought to assess the efficacy of facial translocation in the management of tumors of the skull base and paranasal sinuses. STUDY DESIGN AND SETTING: From July 1993 to December 1999, 75 patients, aged 3 to 102 years old, underwent facial translocation. Thirty-three (44%) patients also underwent a combined neurosurgical procedure. Nineteen (25%) had previous surgery. These patients were followed up to 6 years. RESULTS: There were 21 benign and 54 malignant tumors. There were no perioperative deaths. The morbidity rate was 31%. Of the 54 patients with malignant tumors, the actuarial 3-year survival rate was 59%, whereas the local control rate was 54%. CONCLUSION: The facial translocation technique offers favorable exposure of the critical zones of the anterior and middle cranial base, thus facilitating extensive resection and reconstruction. SIGNIFICANCE: This study demonstrates that facial translocation is one of the best surgical approaches to the skull base.  相似文献   
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Ching-Hao Chang  MD    Yuan-Li Liao  MD    Hong-Shang Hong  MD  Ph  D 《Dermatologic surgery》2003,29(7):775-779
BACKGROUND: Cutaneous metastasis from adenoid cystic carcinoma of the salivary gland is very rare. OBJECTIVE: To present an unusual case of cutaneous metastasis from adenoid cystic carcinoma of the right parotid gland. METHODS: A 63-year-old woman with multiple subcutaneous nodules on the abdomen and a gradually enlarged mass over the right parotid area was examined. A skin biopsy was taken from one of the abdominal nodules. RESULT: Skin biopsy demonstrated the characteristic histopathologic features of metastatic adenoid cystic carcinoma. A subsequent computerized tomography of the head and neck revealed a huge soft tissue mass involving the right parotid gland. Computerized tomography of the chest revealed extensive nodular pleural thickening, and pleural biopsy also showed typical histopathologic features of metastatic adenoid cystic carcinoma. All of these results are consistent with the diagnosis of an adenoid cystic carcinoma of the right parotid gland with disseminated metastases. CONCLUSION: We report a rare case of cutaneous metastasis from adenoid cystic carcinoma of the right parotid gland. The presentation of cutaneous metastasis is often nonspecific and may mimic benign lesions. Subcutaneous nodules that are rapidly developing or eruptive, are rapidly growing and have stony hardness in nature, have pain or tenderness, and have nonhealing ulceration remind us of the possibility of cutaneous metastases. Dermatologists and dermatologic surgeons should keep the diagnosis of cutaneous metastasis in mind and always perform skin biopsy when encountering these lesions.  相似文献   
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