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Calcifying epithelial odontogenic tumor (CEOT) is a benign, locally aggressive odontogenic neoplasm characterized by sheets and nests of epithelial cells with deeply eosinophilic or occasionally clear cytoplasm, calcifications, and eosinophilic amorphous material that stains positive for amyloid. Although many cases of CEOT are associated with impacted teeth and occasionally appear radiographically as dentigerous cysts, a true cystic variant has not been previously reported. We report a 15-year-old white male with a large cystic maxillary lesion that filled most of the left maxillary sinus. It deformed the medial wall, the inferior orbital floor, and caused narrowing of the left inferior meatus. Histologically, the cystic lining showed characteristics of CEOT. An intraluminal component that featured histologic characteristics of CEOT was identified during surgery. The lesion was enucleated and the postsurgical course of the patient was uneventful. Because follow-up has been for less than 1 year, a meaningful long-term prognosis cannot be determined at present. However, the patient has not reported any symptoms or signs of recurrence during the follow-up period.  相似文献   
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We report seven children in whom traumatic haemarthrosis of the hip had produced lateral subluxation of the femoral head, which is different from the apparent displacement seen in Perthes' disease. In all seven cases, aspiration of the haemarthrosis allowed reduction of the femoral head, and follow-up for a mean of 14 months revealed no evidence of avascular necrosis of the proximal femoral epiphysis. Traumatic haemarthrosis of the hip in children appears to be a clinical entity which can produce femoral head subluxation. Aspiration and traction is the treatment of choice and can cure the condition.  相似文献   
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Intra-articular fractures of the proximal tibia present a wide spectrum of injury patterns with associated soft tissue injury. The last two decades have seen the techniques of management evolve from extensive open reduction and rigid internal fixation to arthroscopy-assisted minimal invasive surgery (MIS) and biologically benign internal fixation. The ultimate aim is to prevent the occurrence of late degenerative arthritis. This could be achieved in selected patients using minimal invasive surgery, which offers the advantages of better visualisation and management of intra-articular soft tissue injuries, confirmation of fracture reduction viewed from the joint surface, faster rehabilitation and fewer wound complications.  相似文献   
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Hypersensitivity reactions occurring during barium studies of the gastrointestinal tract are rare. A case is presented with radiographically demonstrated angioedema in the stomach and small bowel accompanied by allergic rhinitis, which was apparently an allergic response to the barium sulfate suspension. The reaction was documented twice during separate challenges to the barium suspension performed several months apart.  相似文献   
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1. The present study describes the role of Ca2+ in the regulation of the hepatic vasopressin V1 receptor. With low concentrations of Ca2+, there was a small increase in [3H]-arginine vasopressin [( 3H]-AVP) binding, but above 10 mM, Ca2+ decreased the binding of this agonist. In contrast, low concentrations of Mg2+ were associated with a dramatic concentration-dependent increase in [3H]-AVP binding, reaching a maximal effect of 650% above control at concentrations ranging between 1-5 mM. At higher concentrations of Mg2+, the stimulatory effect of this cation was less pronounced, falling to 210% of control at 100 mM Mg2+. Strikingly, Ca2(+)-inhibited the stimulatory effect of Mg2+ in a concentration-dependent fashion. 2. Saturation binding data revealed that Ca2+ (2 to 10 mM) per se promotes the high affinity conformation of the V1 receptor for the agonist binding with the KD decreased from a control value of 2.3 nM to 0.5 nM in the presence of 10 mM Ca2+. This effect was attenuated with an increase in Ca2+ above 10 mM. With an increase in Ca2+ to 20 mM, however, the Bmax for [3H]-AVP binding was decreased. Ca2+ also decreased the high affinity/high capacity state (KD 100 pM) of the receptor induced by 1 mM Mg2+ for agonist interaction. 3. [3H]-V1 antagonist binding was inhibited by both Ca2+ and Mg2+. The IC50 values (mean +/- s.e. mean) for Ca2+ and Mg2+ were 32 +/- 8 and 53 +/- 9 mM respectively. Maximal inhibition achieved at 100 mM was 29% for Ca2+ and 42% for Mg2+.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Despite the common occurrence of pleomorphic adenoma of major salivary glands, intranasal pleomorphic adenoma are rare. We present a ease of pleomorphic adenoma of the nasal septum along with a brief review of literature. The histological nature of this lesion in comparison to other salivary gland tumours and the importance of an accurate diagnosis has been stressed.  相似文献   
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