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101.
Intratemporal vascular tumors: detection with CT and MR imaging   总被引:1,自引:0,他引:1  
The diagnostic contributions of computed tomography (CT) and magnetic resonance (MR) imaging were compared in 12 patients with benign intratemporal vascular tumors (hemangioma or vascular malformation). The tumors included six in the internal acoustic canal and six in the geniculate ganglion region. Clinical and histologic correlations were made. Two of the six patients with tumors in the internal acoustic canal underwent CT, and both required gas cisternography to show the tumor. Five patients in that group underwent MR imaging, and all five studies showed the tumor. All six patients with geniculate ganglion tumors underwent CT. Results in one study were questionable, and five showed the tumor. Five patients in this group underwent MR imaging, but the MR findings were positive in only two cases. MR imaging should therefore be performed before CT in the evaluation of facial nerve dysfunction, as it demonstrated all tumors in the internal acoustic canal and some in the geniculate ganglion region. If MR findings are negative, CT should then be performed to rule out a possible geniculate ganglion lesion.  相似文献   
102.
Treatment of ruptured hepatocellular adenoma   总被引:4,自引:0,他引:4  
BACKGROUND: As the morbidity and mortality rates associated with emergency resection in patients with a ruptured hepatocellular adenoma are high, the authors have favoured initial non-operative management in haemodynamically stable patients. METHODS: A retrospective study was performed to evaluate the treatment of ruptured hepatocellular adenoma. RESULTS: Over a 21-year interval, 12 patients presented with a ruptured hepatocellular adenoma. Haemodynamic observation and support was the initial management in all 12 patients. Three underwent urgent laparotomy and gauze packing because of haemodynamic instability; no emergency liver resection was necessary. Eight patients had definitive surgery; three developed postoperative complications but none died. Regression of the tumour was observed in three of four patients treated conservatively. CONCLUSION: The initial management of a ruptured hepatocellular adenoma should be haemodynamic stabilization. Definitive resection is required for rebleeding or for tumours exceeding 5 cm in diameter. A conservative approach may well be justified in case of regression of an asymptomatic adenoma.  相似文献   
103.
In a prospective study of 65 patients with bile duct obstruction, various radiologic modalities were compared for their capability to demonstrate the level and cause of obstruction and to indicate accurately tumor resectability. Ultrasound (US) was performed in 65 patients, computed tomography (CT) in 51, direct cholangiography (DC) in 57, and angiography in 35. The level of obstruction was correctly indicated by US in 95% of patients and by CT in 90%, and the cause was correctly indicated by US in 88%, by CT in 63%, and by DC in 89%. In predicting tumor resectability, US was correct in 71% of patients, compared with 42% for CT, 58% for DC, and 25% for angiography. US therefore appears to be the single most useful modality in the evaluation bile duct obstruction.  相似文献   
104.
长鞭红景天化学成分的研究   总被引:10,自引:0,他引:10  
彭江南  葛永潮  李晓晖 《药学学报》1996,31(10):798-800
长鞭红景天化学成分的研究彭江南,葛永潮,李晓晖(军事医学科学院放射医学研究所,北京100850)红景天是滋补强壮药物,目前正引起人们极大的兴趣,现已有一些产品上市。我们曾对数种红景天的化学成分进行过研究[1~4]。长鞭红景天(Rhodiolafast...  相似文献   
105.
106.
MR fluoroscopy: initial clinical studies   总被引:2,自引:0,他引:2  
Magnetic resonance (MR) fluoroscopy is a method for high-speed MR image acquisition with the goals of short acquisition time per image (500 msec or less), high image rate (10 images or more per second), and high-speed image reconstruction (150 msec or less from data acquisition to image display). The authors present their results with the first two goals in volunteers. MR fluoroscopic image data were acquired with a limited flip angle pulse sequence with reduced repetition times (TRs) and fewer phase encodings used per image. The sequence was applied continuously, and images were formed by updating one set of data with data from the most recently taken measurements. Sample head images were generated with TR/echo times as small as 11/5.5 msec and 48 phase encodings for a total acquisition time of about 500 msec. Images were acquired while the volunteer flexed his head. Artifacts from the motion became less evident on images as progressively shorter acquisition times were used.  相似文献   
107.
108.
109.
Automatic implantable cardioverter defibrillators (AICDs) were studied in three groups: (a) Serial radiographs were reviewed in 51 clinic patients. Twenty of 96 (21%) AICD patches distorted with time. (b) Thirty-six postoperative computed tomographic (CT) scans of asymptomatic patients revealed that pericardial fluid collections were frequent during the month after surgery but rare beyond that. Echocardiography was insensitive for these collections. CT also demonstrated dense fibrosis around some distorted patches, months after surgery. (c) Five other patients with pericardial infection had distorted patches, and the four studied with CT had fluid beneath their patches. (d) A case of constrictive pericarditis had distorted patches but was not diagnosed with CT. The authors conclude that distorted patches may indicate postoperative complications and that CT is the imaging modality of choice.  相似文献   
110.
George  JN; Pickett  EB; Heinz  R 《Blood》1986,68(1):307-309
Cryoprecipitate has been demonstrated to correct the bleeding abnormality of patients with some congenital (storage pool disease) and acquired (uremia) platelet abnormalities, but the reason for this effect is unknown. We found significant platelet contamination in plasma harvested to prepare fresh frozen plasma and cryoprecipitate. The platelet membrane microparticles produced by freezing and thawing of the plasma were highly concentrated in cryoprecipitate and may contribute to its therapeutic effect.  相似文献   
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