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61.
The reproducibility of echo-Doppler measurements of portal vein and superior mesenteric artery blood flow has not been extensively studied. In the present study, two groups of subjects were examined to test inter- and intra-observer reproducibility. Each study population consisted of 15 non-portal hypertensive and 15 portal hypertensive subjects. With a standardized technique, the cross-sectional area and velocity of blood flow in the portal vein and superior mesenteric artery were recorded in triplicate by skilled operators. The flow volume of each vessel was calculated by multiplying the cross-sectional area by the velocity of blood flow. The measurements were performed in a blind fashion over a 60 min period. The reproducibility of measurements was assessed by calculation of intraclass correlation coefficients and coefficients of variation. The intra-observer intraclass correlation coefficient was 0.77 for portal vein blood flow and 0.84 for superior mesenteric artery blood flow, suggesting good reproducibility. The intra-observer coefficient of variation was 11 and 9%, respectively. In contrast, the interobserver intraclass correlation coefficient was calculated to be 0.49 for portal blood vein blood flow and 0.57 for superior mesenteric artery blood flow, indicating fair reproducibility. In addition, the interobserver coefficients of variation were calculted to be 20 and 18%, respectively. These data suggest that intra-observer reproducibility in echo-Doppler measurements of portal vein and superior mesenteric artery blood flow is acceptable but inter-observer reproducibility is not. Examination by a single operator, rather than multiple operators, is therefore advisable. Even when measurements are performed by a single investigator an approximate variance of 10% in the measurement in a single subject should be expected.  相似文献   
62.
The purpose of this study was to determine the level of serum hepatitis Be antigen (HBeAg) during hepatitis B virus carriage and its clinical significance. The mean level of serum HBeAg, quantitated by solid-phase enzyme immunoassay, was 5924 units in asymptomatic carriers (s.d. = 5534, n= 100), 3044 units in patients with chronic persistent hepatitis (s.d. = 4826, n= 34), 3599 units in chronic active hepatitis (s.d. = 4953, n= 45) 1348 units in liver cirrhosis (s.d. = 2379, n= 25) and 766 units in hepatocellular carcinoma (s.d. = 1257, n= 18). In the 10 HBeAg-positive patients with chronic active hepatitis, the fluctuation in HBeAg level was followed by changes in alanine aminotransferase (ALT) activity. Among the 36 peaks of HBeAg and ALT, HBeAg peaks preceded ALT peaks in 22 and simultaneous peaks were present in 14. The changes of HBeAg level were closely related to increase in disease activity as estimated by ALT activities; therefore, HBeAg quantitation can be a useful predictor of disease activity in chronic hepatitis B.  相似文献   
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64.
Bile acid metabolism after two-thirds partial hepatectomy (PH) in rat was studied. Bile acid kinetics (i.e. synthesis rate and pool size) were determined by wash out method combined with gas liquid chromatography, and serum bile acids by gas liquid chromatography-mass spectrometry. Serum bile acid concentration was highest on the third day after PH, as the liver regeneration progressed but it gradually decreased with increasing cholic acid (CA)/chenodeoxycholic acid (CDCA), reflecting impaired hepatic uptake of bile acids and/or cholestasis during the early post-hepatectomy period. Predominance of CA in bile acid synthesis, pool, and biliary secretion was also found. On the third day after PH, liver weight recovered to 66% of the control value, but enhancement of bile acid synthesis was not observed. Consequently, pool size remained at 50% of control. On the seventh day, synthesis of bile acid, especially of CA, was enhanced and pool size and liver weight returned to 68 and 72% of the respective control values. Bile acid synthesis was returned to the control value on the fourteenth day with concomitant restoration of liver weight and bile acid pool size. These changes in bile acid kinetics parallel the events during hepatic regeneration after PH.  相似文献   
65.
An acoustic screening method for indicating the possible presenceof laryngeal cancer was investigated. Three acoustic parameters,comprising perturbations in pitch-period and peak-amplitudesequences, and vocal noise, were measured from a sustained vowel,e, spoken by the subjects taking part in the investigation.Experiments to discriminate between normal and cancer groupswere performed with voice samples taken from 64 normal controlsubjects and 57 patients with laryngeal cancer. Experimentswere also carried out to test the perceptual significance ofthe three parameters. From the results, we have been able toconclude that their combined use will enable us to build anacoustic screening system for laryngeal cancer.  相似文献   
66.
The effects of vaso-active agents on hepatic function and splanchnic oxygenation were studied in 17 patients with cirrhosis and portal hypertension. Eight patients received vasopressin (0.3 iu/min) and nine patients received nitroglycerin (50 micrograms/min). Both drugs caused a significant reduction in the portal venous pressure gradient. Vasopressin infusion significantly decreased intrinsic clearance of indocyanine green (-23%, P less than 0.01). This may be due to a decreased hepatic perfusion (-28%, P less than 0.01) and portal venous oxygenation (-15% in portal venous oxygen tension, P less than 0.05). In contrast, no changes in hepatic perfusion and portal venous oxygenation were observed after nitroglycerin infusion. Nitroglycerin did not decrease intrinsic clearance of indocyanine green. These results suggest that vasodilators, rather than vasoconstrictors, might be welcome in the treatment of patients with cirrhosis and portal hypertension.  相似文献   
67.
The peritoneal equilibration test (PET) is generally accepted as a valuable tool in individualizing continuous ambulatory peritoneal dialysis (CAPD) treatment schedules in adults. However, the classification of peritoneal permeability as described by Twardowski is not available for children due to differences in peritoneal transport abilities. In this paper, we report the results of the PET for 20 patients aged from 1.5 to 24 years (mean 10.3 years), who started CAPD therapy at age 0–15 years, using Twardowski's standardized technique. D/P creatinine (dialysate to plasma ratio of creatinine at 4 h), D/D0 glucose (the ratio of dialysate glucose at 4 h dwell time to dialysate glucose at 0 dwell time), and the residual volume (RV) in the abdominal cavity were calculated. The mean and standard deviation values for D/P creatinine and D/D0 glucose were of a higher permeability level than those reported in Twardowski's data. Furthermore, a significant correlation of creatinine and glucose with fluid drainage ability of the peritoneum were observed. A large amount of RV (425±125 mL/m2) was detected in the patients' peritoneal cavity and this had a significant correlation with dialysate leak occurrences. The authors suggest that the RV would be an indicator for leaks and especially latent leaks. The cause of a large RV is unknown, but there is a probability that drainage volume and transport rates of metabolites decrease because the concentration of the instilled dialysate is immediately diluted by a large RV within the peritoneum.  相似文献   
68.
The patient was a 7-year-old girl with early onset urticarial cutaneous lesions and was later complicated with aseptic meningitis. Her skin lesions occurred in the infantile period and were diagnosed as urticaria, but did not disappear with antihistamines and were recurrent and persistent. In addition, she had experienced an episode of headache about once a month since 1991, when she was 4 years old, and was diagnosed as aseptic meningitis. All studies including skin biopsy for urticarial vasculitis (UV) and systemic lupus erythematosus (SLE) were negative except for the data from non-specific inflammations. A systemic corticosteroid therapy dramatically reduced her symptoms. An unusual clinical course for this patient is described. It might suggest that this case is a presentation of the disease entity of UV, chronic urticaria and possibly SLE. To our knowledge, a similar case has not been previously reported.  相似文献   
69.
Recently, it has come to be accepted that the result of the tilt test is specific to neurally mediated syncope (vasovagal syncope). Only rarely is a case of paroxysmal atrial fibrillation without any organic diseases in childhood reported. A case reported here of a 14-year-old boy with neurally mediated syncope; which was complicated by paroxysmal atrial fibrillation, and which was diagnosed by performing the tilt test. Atrial fibrillation can be induced by the extraordinary stimulation of the vagal nerve during syncope. In a child, neurally mediated syncope complicated with paroxysmal atrial fibrillation has not been previously reported.  相似文献   
70.
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