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Velo-cardio-facial syndrome (VCFS) and DiGeorge syndrome (DGS) are developmental disorders characterized by a spectrum of phenotypes including velopharyngeal insufficiency, conotruncal heart defects and facial dysmorphology among others. Eighty to eighty-five percent of VCFS/DGS patients are hemizygous for a portion of chromosome 22. It is likely that the genes encoded by this region play a role in the etiology of the phenotypes associated with the disorders. Using a cDNA selection protocol, we isolated a novel clathrin heavy chain cDNA (CLTD) from the VCFS/DGS minimally deleted interval. The cDNA encodes a protein of 1638 amino acids. CLTD shares significant homology, but is not identical to the ubiquitously expressed clathrin heavy chain gene. The CLTD gene also shows a unique pattern of expression, having its maximal level of expression in skeletal muscle. Velopharyngeal insufficiency and muscle weakness are common features of VCFS patients. Based on the location and expression pattern of CLTD, we suggest hemizygosity at this locus may play a role in the etiology of one of the VCFS-associated phenotypes.   相似文献   
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Computed tomographic detection of nonbeta pancreatic islet cell tumors   总被引:6,自引:0,他引:6  
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Early diagnosis and active management of trans-anal rectal injuries is essential for a favorable outcome. Intraperitoneal free air (IFA) is usually diagnosed by an erect Chest X-ray. Point-of-care ultrasound has been recently used to detect IFA. We report a 45-year-old male who presented to the Emergency Department with lower abdominal peritonitis. Surgeon-performed portable point-of-care ultrasound as an extension of the abdominal examination revealed an inflamed omentum with hypoechoic stranding, thickened non compressible small bowel, and free fluid in the pelvis. A transverse abdominal section of the right upper quadrant showed free intraperitoneal air. Rectal examination revealed a longitudinal rectal tear. Laparotomy has confirmed the sonographic findings. There was a 12 cm intraperitoneal tear of the anterior wall of the rectum which was necrotic. This case clearly demonstrates that portable point-of-care ultrasound gives very useful detailed information even when performed by a non radiologist. Surgeons should be encouraged to use point-of-care ultrasound after appropriate training.  相似文献   
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Saba  HI; Saba  SR; Dent  J; Ruggeri  ZM; Zimmerman  TS 《Blood》1985,66(2):282-286
Type IIB von Willebrand disease is characterized by enhanced ristocetin- induced platelet aggregation and absence of large von Willebrand factor multimers from plasma. An alteration of the von Willebrand factor molecule resulting in increased reactivity with platelets appears to be the basis for these abnormalities. We have now identified a new variant of type IIB von Willebrand disease in a family in which the four affected members also have chronic thrombocytopenia, in vivo platelet aggregate formation, and spontaneous platelet aggregation in vitro. In spite of repeatedly prolonged bleeding times and persistent thrombocytopenia, their bleeding diathesis is only moderate.  相似文献   
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Splanchnic artery aneurysms and pseudoaneurysms: transcatheter embolization   总被引:9,自引:0,他引:9  
Baker  KS; Tisnado  J; Cho  SR; Beachley  MC 《Radiology》1987,163(1):135-139
Over the past 7 years, eight patients with splanchnic artery aneurysms and pseudoaneurysms were studied and treated. Transcatheter embolization resulted in occlusion of the lesions in all eight patients. Potentially risky and difficult surgery was avoided completely in four patients. Three patients had elective surgery at a later date when their condition was more stable. The remaining patient had definitive surgery after embolization. Transcatheter embolization should be the initial treatment of choice in splanchnic artery aneurysms and pseudoaneurysms.  相似文献   
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