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991.
We describe a method for quantitative determination of fluphenazine in human plasma, based on gas chromatography of its trimethylsilyl derivative and the use of a structurally similar internal standard. We determined its concentrations in plasma of four patients who were receiving the drug intramuscularly as its decanoate, in doses ranging from 12.5 to 250 mg; the concentrations in the plasma of these patients ranged from 0.25 to 11.8 microgram/liter. The precision (CV) of the method over the range 2 to 17 microgram/liter was 6.8% when fluphenazine was extracted from 5 ml of plasma. Of 18 other drugs tested, only thioridazine and the cis and trans forms of flupenthixol interfere with the determination.  相似文献   
992.
993.
Imaging congenital heart disease   总被引:1,自引:0,他引:1  
When defined in a broad sense, imaging is the most important aspect of modern pediatric cardiovascular medicine. Definition of anatomic defects is now accurately and easily obtained with physical inspection, x-ray technology (including roentgenology, fluoroscopy, and cineangiography), and echocardiography. Echocardiography, with the addition of Doppler and color flow Doppler, is the most important development in clinical cardiac imaging in the past decade. The exciting new areas of "imaging" are in cardiac functional analysis and metabolic evaluation. Viewing the heart at the cellular or biochemical level is the challenge of the future. The new technology offered by computed tomography, positron emission tomography, and nuclear magnetic resonance imaging begins to provide the ability to image the domain of cellular and biochemical function.  相似文献   
994.
Partial splenic embolization in children with hypersplenism   总被引:15,自引:0,他引:15  
Partial splenic embolization (PSE) was successfully accomplished in 10 of 11 children, aged 2-9, who had portal hypertension or variceal bleeding. Nine of the 11 children had undergone portoenterostomy (Kasai operation) for biliary atresia, and two had portal vein thrombosis. After embolization these children had a longer period of fever (mean = 23.7 days) and elevated white blood cell (WBC) count (above 10,000, mean = 13.6 days) than adults who have undergone the same procedure. The leukopenia and thrombocytopenia of hypersplenism were corrected by PSE in seven of eight children, and the condition of the eighth child improved. Among ten patients who had experienced episodes of variceal hemorrhage, the frequency of bleeding episodes was reduced from an average of 2.87 per year before PSE to 0.67 per year after PSE. There were no splenic abscesses and no other significant complications of the treatment. Ultrasound (US) evaluation after embolization demonstrated hypoechogenicity of the infarcted areas and tiny, linear echoes scattered throughout the spleen typical of postinfarction intravascular gas. All nine children who underwent follow-up Tc-99m sulfur colloid scanning showed evidence of splenic regeneration, though none has had recurrence of clinical symptoms. Splenic regeneration following PSE may occur more frequently in children than in adults.  相似文献   
995.
A recently developed nonradioisotopic 52Cr technique was used to measure either red cell volume or posttransfusion recovery of stored red cells. The experimental method uses Zeeman electrothermal atomic absorption spectrophotometry to measure red cell chromium. Results from the 52Cr method were compared with those from 51Cr single-label and 125I-albumin/51Cr double-label procedures using 49-day AS-1 red cell concentrates drawn and prepared according to standard procedures. In the first group of five donors, red cell volume was estimated concurrently with both 52Cr-labeled fresh red cells and 125I-albumin. The latter measured plasma volume from which red cell volume was estimated on the basis of the hematocrit (125I red cell volume). 51Cr-labeled stored red cells were transfused to measure posttransfusion recoveries. The correlation between 52Cr and 125I red cell volumes was significant (r = 0.68, p less than 0.01), and, in this group, the differences were not significant (p less than 0.05). Twenty-four-hour posttransfusion recoveries of 51Cr-labeled stored red cells averaged 66 +/- 5 percent when measured with the 125I/51Cr technique and 69 +/- 8 percent when measured with the 52Cr/51Cr method. In the second group of five donors, red cell volume was estimated by the 125I-albumin technique, and the posttransfusion recovery of stored red cells was quantitated by 51Cr- and 52Cr-labeled stored cells simultaneously. In this group, posttransfusion recoveries with 125I/51Cr averaged 73 +/- 7 percent; with 125I/52Cr, they averaged 75 +/- 10 percent. Using the single-label method of calculation, recoveries averaged 76 +/- 7 and 75 +/- 10 percent for the 51Cr and 52Cr methods, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
996.
997.
998.
Meningovascular syphilis: CT and MR findings   总被引:4,自引:0,他引:4  
Holland  BA; Perrett  LV; Mills  CM 《Radiology》1986,158(2):439-442
The radiologic findings in three cases of meningovascular syphilis are presented. Angiography demonstrated varying degrees of narrowing and ectasia of the supraclinoid carotid, basilar, and proximal anterior and middle cerebral arteries, as well as distal branches. Computed tomography (CT) showed multifocal infarction with variable enhancement. Similarly, in the one case studied with magnetic resonance (MR), several regions of high signal intensity on T2-weighted sequences were found, which were compatible with foci of ischemia. Although the radiologic findings are nonspecific, the diagnosis of meningovascular syphilis should be considered in patients with vasculitis of uncertain etiology.  相似文献   
999.
1000.
Treatment of neurological disorders with intravenous immunoglobulin (IVIg) is an increasing feature of our practice for an expanding range of indications. For some there is evidence of benefit from randomised controlled trials, whereas for others evidence is anecdotal. The relative rarity of some of the disorders means that good randomised control trials will be difficult to deliver. Meanwhile, the treatment is costly and pressure to "do something" in often distressing disorders considerable. This review follows a 1 day meeting of the authors in November 2000 and examines current evidence for the use of IVIg in neurological conditions and comments on mechanisms of action, delivery, safety and tolerability, and health economic issues. Evidence of efficacy has been classified into levels for healthcare interventions (tables 1 and 2).  相似文献   
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