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OBJECTIVE: Pamidronate has been studied as a therapeutic drug for various osteopenic diseases. However, avascular osteonecrosis in the jawbone has been recently reported in patients receiving pamidronate. The objective of this study was to examine the effect of pamidronate on bone regeneration in a controlled animal model. MATERIALS AND METHODS: To determine the effect of parmidronate on bone healing in a local bony defect area, a rabbit calvarial bony defect model was used and poly L-lactide-co-glycolide (PLGA) used as a drug carrier material. Four defect groups were made in each rabbit calvaria and the defects were treated as follows: untreated bony defect (group 1), PLGA only (group 2), 2 mg of pamidronate with PLGA (group 3), and 3 mg of pamidronate with PLGA (group 4). Bone healing was evaluated by radiography and histology at 1, 2, 4, 6, and 8 weeks after surgery. RESULTS: In radiographic analysis, radiopacity was lower in pamidronate groups than non-operated rabbit calvarial bone at all observation points (P < .05). In histological analysis, the initial bone formation at 1 week was not different among groups, but it was much lower in the pamidronate groups than in the control or PLGA group after 2 weeks. Newly formed bone at 1 week underwent avascular necrosis after 2 weeks in both pamidronate groups. Avascular necrosis was not observed until 8 weeks in both topically applied pamidronate groups. CONCLUSION: Collectively, pamidronate inhibits bone healing in rabbit calvarial bony defect and it may explain the avascular necrosis of the jaws in patients receiving pamidronate.  相似文献   
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Emphysematous cystitis is characterized by gas collection within the bladder wall and lumen. We report two cases of emphysematous cystitis of the urinary bladder in a 67-year-old and a 63-year-old women. They presented with bladder irritation symptoms such as dysuria, hematuria and frequency. Urinalysis showed pyuria. Cystoscopic examination revealed that bladder mucosa was studded with vesicles varying in size and arranged in clumps. CT scans of the pelvis showed mottled gas bubbles within the bladder. They were treated with antibiotics. Four days after the treatment, the symptoms subsided and plain abdominal film showed no evidence of gas shadows in the pelvic cavity.  相似文献   
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The determination of a unicellular or a multicellular origin of a tumor is an important due for understanding its etiology. To investigate this issue, we performed clonality assay of cervix cancer using polymerase chain reaction based on highly polymorphic locus of the androgen receptor gene, in which methylation of DNA correlates with inactivation of X chromosome. DNA samples were obtained from formalin-fixed, paraffin-embedded tissue of 20 invasive epidermoid carcinomas and 10 carcinoma in situ. Seven of ten carcinoma in situ, heterozygous for the androgen receptor locus, were monoclonal pattern. Among twenty invasive epidermoid carcinomas, eighteen of which showed heterozygous, twelve were monoclonal pattern and six were polyclonal pattern. We conclude that carcinoma in situ arises from a single cell. In invasive epidermoid carcinoma, most cases were monoclonal, although some cases were polyclonal. These suggest that invasive carcinoma of the cervix does not always arise from a single cell, but may arise from several cells with different mechanisms.  相似文献   
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This study was designed to investigate the effect of cholestyramine on the formation of pigment gallstones in high carbohydrate diet-fed hamsters and whether that effect occurred because of cholecystokinin action. Forty seven hamsters were divided into three groups: group I(n = 16) was fed on normal rodent chow(43% carbohydrate), group II(n = 14) was fed on a high CHO diet(65% carbohydrate), group III(n = 17) was fed on a high CHO diet containing 4% cholestyramine. Gallstones developed in 0% of group I, 42.9% of group II and 5.9% of group III(P < 0.05, group II vs III). To evaluate the chronic status of cholecystokinin level, the wet weight of pancreas and the average area of pancreatic acinar in microscopic high power field were measured. There was no significant difference between group II and group III in pancreatic weight and average area of pancreatic acinar(P > 0.05). In gallbladder bile analysis, there was also no significant difference between group II and group III in cholesterol, phospholipid, total calcium, total bilirubin and bile acid levels. In conclusion, cholestyramine decreases the frequency of pigment gallstone formation in high CHO diet-fed hamsters, but it is not clear whether the mechanism of cholestyramine decreasing the gallstone formation is due to the action of cholecystokinin.  相似文献   
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The purpose of this study was to investigate whether (18)F-FDG PET/CT is useful for localizing dystonic cervical muscles in patients with idiopathic cervical dystonia (ICD) by comparing disease severity before and disease severity after botulinum toxin (BT) injection into hypermetabolic muscles. METHODS: Six patients with ICD underwent (18)F-FDG PET/CT. Dystonic muscles suitable for BT injection therapy were defined as those showing diffusely increased (18)F-FDG uptake. RESULTS: Hypermetabolic cervical muscles were identified in all 6 patients. In 2 patients who underwent PET/CT both in a supine position and in a sitting position during (18)F-FDG uptake, abnormal hypermetabolic muscles were observed by PET/CT only when patients were in the sitting position with their heads and necks in the adopted abnormal involuntary posture. Symptoms were significantly improved in 4 patients who underwent BT injection therapy guided by PET/CT and who were clinically monitored. CONCLUSION: (18)F-FDG PET/CT is potentially useful for identifying dystonic cervical muscles for BT therapy in patients with ICD.  相似文献   
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