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51.

Purpose

To investigate the effect of using effervescent powder (EP) on the efficacy of multi-detector computed tomography (MDCT) in detection and grading of esophageal varices in cirrhotic patients by considering endoscopy as the gold standard.

Materials and methods

Ninety-two cirrhotic patients undergoing biphasic liver MDCT followed by upper gastrointestinal endoscopy within 4 weeks of MDCT were prospectively evaluated. The patients were divided into two groups before MDCT. The first group (n = 50) received effervescent powder (EP) before and during MDCT procedure and the second group did not receive (n = 42). The presence, size and grade of the esophageal varices were evaluated. MDCT findings were compared with endoscopic results. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of MDCT with EP and without EP were calculated and compared. Correlations between the grades of the varices for each group based on MDCT imaging and endoscopic grading were also evaluated.

Results

The sensitivity, specificity, accuracy, PPV, and NPV of MDCT were 100%, 88%, 96%, 94%, and 100%, respectively, in the EP group, whereas they were 76%, 67%, 74%, 89%, and 43%, respectively, in the non-EP group. Correlations between the grades of the esophageal varices on MDCT and endoscopy were significant in both groups (r = 0.94, p < 0.001 for EP group and r = 0.70, p < 0.001 for non-EP group).

Conclusion

During periodic CT scanning of cirrhotic patients, use of EP increases the success rate of MDCT for detection and grading of esophageal varices.  相似文献   
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Introduction:

In this study, we define the characteristics of perfusion computed tomography (CT) in an experimental model of testicular torsion.

Methods:

Twenty male Sprague-Dawley rats were included for the study. Torsion was applied to 10 rats and perfusion CT was performed in the first hour to evaluate the following perfusion parameters: blood flow (BF), blood volume (BV) and time to peak (TTP) values. Detorsion was done for the same rats, and perfusion CT was repeated 2 hours later to evaluate reperfusion. Ten rats were left as part of the control group.

Results:

There is significant statistical correlation between the BF and BV values in the torsion and control groups (p = 0.001 and p = 0.001, respectively). There is no statistical correlation of the TTP parameters between the groups. No correlation was found between torsion and detorsion perfusion parameters.

Conclusion:

Perfusion CT can demonstrate the testicular perfusion insult in an experimental model of torsion. Perfusion CT may be an alternative method for diagnosis of torsion in indeterminate cases. Following detorsion an interval of 2 hours is not sufficient for demonstrating luxury perfusion of the testis.  相似文献   
55.
The objective of this study was to determine the effects of various physical interventions such as centrifugation regimes, Percoll gradient separation, and repeated pipetting on various viability parameters of epididymal sperm of Fischer 344 (F-344) and Sprague-Dawley (SD) rat strains. Three experiments were conducted. In experiment 1, sperm motility and acrosomal and membrane integrity were compared after exposing sperm samples to 200, 400, 600, and 800 x g centrifugal forces for 5, 10, or 15 minutes. In experiment 2, sperm motility and acrosomal and membrane integrity were compared after passing them through a Percoll separation using centrifugal forces of 600, 800, 1000, and 1200 x g for either 15 or 30 minutes. In experiment 3, the effect of repeated pipetting (2, 4, 6, 8, and 10 times) on motility and membrane integrity of rat sperm was compared with that on mouse, ram, bull, and boar sperm. The results revealed that both F-344 and SD rat sperm motility and membrane integrity were significantly affected by centrifugation (P < .05). The acrosomal integrity of SD rat sperm was affected after using 800 x g centrifugation force for 10 or 15 minutes (P < .05), whereas F-344 rat sperm acrosomal integrity was not affected by any centrifugation regimes (P > .05). Sperm from SD rats also had higher motility and membrane integrity loss than did sperm from F-344 rats after centrifugation and pipetting (P < .05). Percoll gradient separation did not cause significant motility loss or acrosomal damage to either F-344 or SD sperm (P > .05). Repeated pipetting had a dramatic adverse effect on both rat and mouse sperm motility (P < .05) as compared with sperm from bull, boar, and ram, which were not affected at all (P > .05). These data suggest that rat sperm have unique properties that need to be considered during centrifugation, Percoll gradient separation, and pipetting procedures.  相似文献   
56.
The main goal of this study was to evaluate knowledge of, perceptions of, and attitudes toward epilepsy and then to correlate knowledge with quality of life and stigmatization of children with epilepsy and their families. Specific questionnaires were administered to children aged 8 to 17 with epilepsy (n=220) and their parents (n=313). Poor school performance, less social support, less self-esteem, higher anxiety, greater stigmatization, and more depressive symptoms were documented in children who were less knowledgeable (P<0.05). Parents were found to be more knowledgeable about the antiepileptic drugs used, understanding both the effects and the side effects of the medications (P<0.05). Family activities were less restricted if they were more knowledgeable and these parents reported worrying less about their children (P<0.05). Knowledge about epilepsy is associated with less perceived stigmatization and social isolation, as well as fewer depressive symptoms and misperceptions.  相似文献   
57.
We investigated the relationship between total serum bilirubin and serum Tau and S100B protein levels, and predicted a cutoff level of bilirubin-induced neurotoxicity in term newborns. Total serum bilirubin, serum Tau, and S100B levels were measured in 92 jaundiced term newborns. A neurologic examination, electroencephalogram, brainstem auditory-evoked response, and otoacoustic emission were performed in the infants on admission and at age 3 months. Serum Tau (r = 0.921, P < 0.001) and S100B (r = 0.927, P < 0.001) levels were correlated with total serum bilirubin levels in all infants. Serum Tau and S100B protein levels remained at a steady level up to a total serum bilirubin level of 19.1 mg/dL, and then demonstrated a significant increase. Mean total serum bilirubin, serum Tau, and S100B levels of infants who manifested auditory neuropathy, neurologic abnormalities, or electroencephalogram abnormalities were significantly higher than in infants without these abnormalities (P < 0.05). Clinical and laboratory findings of bilirubin-induced neurotoxicity developed after a total serum bilirubin level of 22 mg/dL was reached. Serum levels of Tau and S100B proteins in jaundiced term newborns were strongly correlated with early-phase bilirubin encephalopathy.  相似文献   
58.
The objective of this study was to investigate the frequency of sacroiliitis in familial Mediterranean fever (FMF) patients and the role of HLA-B27 and MEFV mutations in the development of sacroiliitis. The study group consisted of 256 FMF patients (male 128, female 128, mean age 27.2 ± 6.3 years). After evaluation of the medical records, 70 patients (27.4%) were determined to have one or more of musculoskeletal manifestations. Sacroiliitis was determined in 18 (32.7%) FMF patients. The frequency of sacroiliitis among all FMF patients was found to be 7%. HLA-B27 was 47% and 6.3% in FMF patients with and without sacroiliitis, respectively. The frequency of M694V mutations in FMF patients with sacroiliitis was 93.7%. Sacroiliitis may be seen more frequently in FMF patients than expected. HLA-B27 positivity and/or M694V mutation may play a role in the development of sacroiliitis and the severity of seronegative spondyloarthropathy.  相似文献   
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