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51.
The intestinal uptake of [14C]oxalate, [14C]glyoxylate, and [14C]glycolate are studied in brush border membrane vesicles (BBMV) isolated from vitamin A-deficient and pair-fed control rats. The data obtained indicate that oxalate and its precursors are transported across the BBMV by passive diffusion. The intestinal uptake of glyoxylate and glycolate remains unaltered in vitamin A deficiency, while uptake rate of oxalate was significantly increased (p less than 0.01) in vitamin A-deficient rats as compared to pair-fed controls. In conclusion, the results indicate that vitamin A deficiency leads to hyperabsorption of oxalate through the gut.  相似文献   
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Spontaneous gall bladder perforation in infants is rare. We report a 3-month-old male infant who presented with progressive abdominal distension, low-grade fever, bilateral hydrocele and acholic stools. Ultrasonography showed free fluid in the peritoneal cavity, which was bile-stained on paracentesis. Surgical exploration revealed sterile biliary peritonitis and a gangrenous gall bladder. Partial cholecystectomy with external biliary drainage resulted in satisfactory recovery.  相似文献   
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Gall bladder perforation is a potentially life-threatening condition. Spontaneous perforation is infrequent and rarely seen in the absence of gallstones but gall bladder perforation is an occasional complication of typhoid fever. If such perforations are not treated in time, mortality rates are very high. We report a case of gall bladder perforation complicating typhoid fever following enteric perforation of the ileum necessitating sequential laparotomies during the same admission.  相似文献   
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Dural sinus thrombosis: study using intermediate field strength MR imaging   总被引:1,自引:0,他引:1  
The magnetic resonance (MR) images of six patients with thrombosis of a dural sinus were reviewed. The diagnosis had been verified by computed tomographic scans in three patients and arteriograms in two; in the sixth patient, only MR imaging was used to confirm the clinical syndrome. In all patients, high-intensity signal was seen from the thrombus within the affected dural sinus on all echoes. This persistent signal intensity allowed intravascular clot to be distinguished from normal causes of increased signal such as flow-related enhancement (entry phenomenon) and even-echo rephasing. MR imaging demonstrated the cause of the thrombosis in three patients: two were secondary to adjacent tumors, and one was secondary to unsuspected mastoiditis. Complications such as infarction were also demonstrated. Using MR imaging, one can easily and safely diagnose thrombosis of a dural sinus. MR should be the imaging method of choice in patients suspected of having thrombosis of a dural sinus.  相似文献   
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Primary intraorbital meningioma and Schwannoma are rare tumours. For them to occur concurrently, or one following soon after another should be considered a curiosity. We present a 40 year old male who reported with proptosis of the right eye and a meningioma was removed surgically. Within 3 months symptoms recurred and a schwannoma was removed at surgery from the same site. Interesting features of the lesion are presented and discussed.  相似文献   
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