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Background: Endoscopic color Doppler ultrasonography (ECDUS) is a useful modality for obtaining color flow images of esophageal varices. Levovist is a microbubble echo‐enhancing agent that improves Doppler ultrasound examination. This study is designed to evaluate the usefulness of ECDUS using Levovist in diagnosing palisade veins of esophageal varices. Methods: The study involved 67 patients with esophageal varices using ECDUS. All 67 patients received Levovist intravenously at a concentration of 300 mg/mL. A 7.5‐mL dose of the contrast agent was injected at a slow infusion rate of 1 mL/min. We compared vessel images detected with precontrast with those detected by enhanced ECDUS. Results: Color flow images of palisade veins were obtained in 16 (23.9%) of the 67 patients with precontrast ECDUS. Vessel images of palisade veins were detected in 15 of 61 F2 type varices (24.6%) and in one of six F3 varices (16.7%). The color flows of these vessels showed a continuous wave on fast‐Fourier transform analysis. Sixteen palisade veins had velocities in the 3.3 cm/s?11.6 cm/s range. Color flow images of palisade veins were obtained in 27 (40.3%) of the 67 cases by enhanced ECDUS using Levovist. Palisade veins could be delineated after Levovist contrast in 11 patients who could not be detected on precontrast ECDUS. After Levovist contrast, color flow images detected with precontrast ECDUS were enhanced in all patients. Conclusion: Endoscopic color Doppler ultrasonography with Levovist contrast can improve the diagnostic quality of the palisade veins in esophageal varices.  相似文献   
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OBJECTIVE: To evaluate the influences the change of the measurement method of pyuria from conventional centrifuged sediment to microchamber uncentrifuged urine for the results of evaluation of antimicrobial agents in clinical study against complicated urinary tract infections. From the viewpoint of international harmonization of judgement criteria, the recent method for counting white blood cells (WBC) in urine has changed from using uncentrifuged urine to using a microchamber in all countries. METHODS: Targeted diseases were non-catheterized complicated urinary tract infection, and cefcapene pivoxil hydrochloride or levofloxacin were used as antimicrobial drug. Pyuria was examined using the counting chamber method, a quantitative method using uncentrifuged urine with a microchamber, and the sedimentation method. RESULTS: Overall clinical efficacy in early evaluation by the two methods in measuring pyuria was evaluated as different in eight patients (7.3%). It was rated excellent in 63 (52.9%), moderate in 32 patients (26.9%) and poor in 24 (20.2%) with an efficacy rate of 79.8% using the counting chamber method, and excellent in 68 (57.1%), moderate in 27 (22.7%) and poor in 24 (20.2%) with an efficacy rate of 79.8% using the conventional sedimentation method CONCLUSION: No significant difference was seen between the two methods of WBC count in urine.  相似文献   
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A prospective follow-up study on hepatitis C virus (HCV) infection was conducted in seven haemodialysis units from April 1990 to March 1995. A total of 634 patients were undergoing maintenance haemodialysis in the seven units. Of those, 302 patients participated in the follow-up study; 179 were initially HCV antibody negative and 123 were initially positive. Nine of the 179 initially negative patients became positive for HCV antibody during the follow-up period. In accordance with the appearance of HCV antibody, indicating new infection of HCV, all nine of these patients were diagnosed with HCV viraemia. As no other routes were apparent, HCV infection in all nine patients was likely due to nosocomial transmission. Prevalence of HCV antibody at the start of follow up was significantly higher ( P < 0.001) in haemodialysis units A-C (37.9%) than in haemodialysis units D-G (17.0%). Incidence of new HCV infection was significantly higher ( P = 0.005) in the former units (2.2% per year) than in the latter (0.2% per year). Ten of the 123 patients who were initially positive for the HCV antibody exhibited a loss of reactivity during the follow-up period; of these 10 patients, nine were negative for HCV-RNA from the start of the study. In conclusion, the incidence of new HCV infection seen in patients undergoing haemodialysis suggests that their risk of acquiring HCV infection is directly related to the prevalence of HCV antibody positive patients being treated in the units.  相似文献   
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Abstract— Zenarestat, (3-(4-bromo-2-fluorobenzyl)-7-chloro-2,4-dioxo-1,2,3,4-tetrahydroquinazolin-1-y1) acetic acid, an aldose reductase inhibitor is metabolized mainly to the glucuronide in rat and man. The glucuronide was purified from urine of volunteers after ingestion of zenarestat. The structure of the glucuronide was confirmed by LC-MS and NMR as 1-O-acyl-β-glucuronide. This compound was unstable at physiological pH, being converted to its structural isomers and the aglycone with half-life of 25 min at pH 7·4 and 37°C in aqueous solution. Enzymatic hydrolysis of the glucuronide was studied in urine, blood and tissues. β-Glucuronidase in human urine contributed little to the hydrolysis of the glucuronide, while in rat urine at pH 6, it was degraded by β-glucuronidase and the formation of zenarestat was clearly faster than its formation in buffer at pH 6. In both rat and human blood, these reactions were accelerated by albumin, although rat red blood cells may also contribute. The rate of degradation was not affected by red blood cell membrane, haemoglobin, globulin, esterases or β-glucuronidase. Arylesterase in rat liver, arylesterase and acetylcholinesterase in the kidney, and β-glucuronidase in both tissues may contribute. Thus, enzymatic degradation of zenarestat 1-O-acyl-β-glucuronide is dependent not only on pH and temperature but also on species and the type of tissue or body fluid.  相似文献   
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Pyruvate dehydrogenase complex (PDHC) deficiency is known to cause congenital lactic acidosis. The case of a 9-month-old female infant with PDHC deficiency caused by a mutation in exon 11 of the pyruvate dehydrogenase (PDH) Elα gene is described. Her facial features were as follows: frontal bossing, upslanting palpebral fissures, a short upturned nose, a long philtrum and low set ears. These anomalies are characteristic not only of a malformation syndrome or chromosomal aberration, but also of PDHC deficiency. Because PDHC deficiency requires early treatment, metabolic disorders should be kept in mind in a patient with dysmorphic features. Further, she had multiple minor anomalies including bilateral inguinal herniae, an umbilical hernia and small hands and feet, which have not been described in previous reports.  相似文献   
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