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The yield of 478 and 558 keV gamma-rays have been measured from water samples containing 0.031-0.500 wt. % boron and 0.0625-0.500 wt. % cadmium, respectively, using a cylindrical 76 mm × 76 mm (height × diameter) LaCl(3):Ce detector. Inspite of interferences between detector-associated and the sample-associated prompt gamma rays, the LaCl(3):Ce detector has excellent resolution for the low energy prompt gamma-rays. An excellent agreement has been observed between the experimental and calculated yield of boron and cadmium prompt gamma ray from water samples.  相似文献   
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Objectives  

To present data on the dental and periodontal status of a convenience sample of 101 ambulant China-born older adults who now live in Melbourne. These older adults participated in a study to assess the prevalence of specific oral diseases.  相似文献   
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Fibrinogen biosynthesis in isolated guinea pig megakaryocytes   总被引:5,自引:0,他引:5  
Leven  RM; Schick  PK; Budzynski  AZ 《Blood》1985,65(2):501-504
Fibrinogen synthesis was investigated in guinea pig megakaryocytes. Purified megakaryocytes were incubated with 35S-methionine in methionine-free incubation medium for 18 hours. Newly synthesized fibrinogen in megakaryocyte lysates enriched with purified carrier guinea pig fibrinogen was immunoprecipitated with a specific anti- guinea pig fibrinogen antiserum produced in rabbits. Proteins in the immunoprecipitates were analyzed with a 3.5% to 10.0% gradient polyacrylamide slab gel electrophoresis and auto-radiography. Radioactivity was detected in a protein band of 340,000 daltons. In order to verify fibrinogen synthesis, immunoprecipitate was analyzed by two-dimensional slab gel electrophoresis: (1) the first dimension separated unreduced fibrinogen using a 3.5% to 10.0% gradient gel; (2) following reduction by 2-beta-mercaptoethanol, fibrinogen chains were separated in the second dimension using a 10% gel. Alpha, beta, and gamma fibrinogen chains, which represented carrier guinea pig plasma fibrinogen, were visualized by Coomassie brilliant blue. Autoradiography identified the incorporation of radioactivity into the three fibrinogen chains. In control experiments, immunoprecipitates, produced by exposing megakaryocyte lysates to preimmune rabbit serum and goat anti-rabbit IgG, were also analyzed by the two-dimensional gel system. Radioactivity was not detected in sites corresponding to the migration of fibrinogen subunits. The study demonstrates that isolated guinea pig megakaryocytes can synthesize fibrinogen. The electrophoretic mobility of newly synthesized fibrinogen and subunits is similar to that of guinea pig plasma fibrinogen.  相似文献   
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OBJECTIVES: We sought to evaluate the diagnostic accuracy and feasibility of bedside pacing stress echocardiography (PASE) as a potential substitute for pharmacologic stress echocardiography in patients admitted to the hospital with new-onset chest pain or worsening angina pectoris. BACKGROUND: Accurate and rapid noninvasive identification and evaluation of the extent of coronary artery disease (CAD) is essential for optimal management of these patients. METHODS: Bedside transthoracic stress echocardiography was performed in 54 consecutive patients admitted to a community hospital with new-onset chest pain, after acute myocardial infarction had been excluded. We used 10F transesophageal pacing catheters and a rapid and modified pacing protocol. The PASE results were validated in all patients by coronary angiography performed within 24 h of the test. Significant CAD was defined as > or =75% stenosis in at least one major epicardial coronary artery. RESULTS: The sensitivity of PASE for identifying patients with significant CAD was 95%, specificity was 87% and accuracy was 92%. The extent of significant CAD (single- or multivessel disease) was highly concordant with coronary angiography (kappa = 0.73, p<0.001). Pacing stress echocardiography was well tolerated, and only 4% of the patients had minor adverse events. The mean rate-pressure product at peak pacing was 22,313+/-5,357 beats/min per mm Hg, and heart rate >85% of the age-predicted target was achieved in 94% of patients. The average duration of the bedside PASE test, including image interpretation, was 38+/-6 min. CONCLUSIONS: Bedside PASE is rapid, tolerable and accurate for identification of significant CAD in patients admitted to the hospital with new-onset chest pain or worsening angina pectoris.  相似文献   
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Background

Fibrosing cholestatic hepatitis C (FCH-C) is a rare entity that occurs among immune-compromised patients resulting from the direct hepatotoxicity of a high intracellular viral load along with an ineffective immune system ultimately leading to a fatal outcome. We have describes herein 4 renal transplant recipients who were diagnosed with FCH-C at our institution in the last 8 months.

Methods

Four renal transplant recipients presented with jaundice and deteriorating liver function tests. They were diagnosed to display FCH-C based on the presence of hepatitis C virus (HCV) RNA and characteristic liver biopsy findings; there was no evidence of any other cause of cholestasis or biliary obstruction.

Results

The patients were men of ages 40, 25, 20, and 27 years. The durations after transplantation were 1.5, 10, 1.5 and 2.0 years, respectively. In all cases pretransplantation screening was negative for HCV antibody, HCV RNA, and hepatitis B surface antigen (HBsAg). All 4 patients were infected with genotype 1, whereas case 2 had coinfection with type 3. Cases 1 and 2 who were treated with interferon and ribavirin, showed improvement in cholestasis but did not achieve a rapid virological response. Case 1 developed graft dysfunction secondary to acute cellular rejection at 4 months after initiation of interferon treatment, which was treated with pulse steroids. Interferon-based therapy was stopped prematurely in both cases due to pancytopenia. Case 3 developed florid pyelonephritis and died without receiving therapy for hepatitis C. Case 4 was managed conservatively by decreasing the immunosuppression with regular monitoring.

Conclusion

FCH-C is difficult to treat and shows high morbidity and mortality rates. Treatment is associated with a risk of graft rejection.  相似文献   
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