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991.
AIM:To evaluate the effects of omeprazole on gastric mechanosensitivity in humans. METHODS:A double lumen polyvinyl tube with a plastic bag was introduced into the stomach of healthy volunteers under fluorography and connected to a barostat device. Subjects were then positioned so they were sitting comfortably, and the minimal distending pressure (MDP) was determined after a 30-min adaptation period. Isobaric distensions were performed in stepwise increments of 2 mmHg (2 min each) starting from the MDP. Subjects were instructed to score feel-ings at the end of every step using a graphic rating scale:0, no perception; 1, weak/vague; 2, weak but significant; 3, moderate/vague; 4, moderate but signifi-cant; 5, severe discomfort; and 6, unbearable pain. After this first test, subjects received omeprazole (20 mg, after dinner) once daily for 1 wk. A second test was performed on the last day of treatment. RESULTS:No adverse effects were observed. Mean MDP before and after treatment was 6.3 ± 0.3 mmHg and 6.2 ± 0.5 mmHg, respectively. One subject before and 2 after treatment did not reach a score of 6 at the maximum bag volume of 750 mL. After omeprazole, there was a significant increase in the distension pres-sure required to reach scores of 1 (P = 0.019) and 2 (P = 0.017) as compared to baseline. There were no changes in pressure required to reach the other scores after treatment. Two subjects before and one after omeprazole rated their abdominal feeling 1 at MDP, and mean (± SE) abdominal discomfort scores at MDP were 0.13 ± 0.09 and 0.04 ± 0.04, respectively. Mean scores induced by each MDP + 2, 4, 6, 8, 10, 12, 14, 16, 18 and 20 (mmHg) were 1.1 ± 0.3, 2.0 ± 0.4, 2.9 ± 0.5, 3.3 ± 0.4, 4.6 ± 0.3, 5.2 ± 0.3, 5.5 ± 0.2, 5.5 ± 0.3, 5.7 ± 0.3, and 5.4, respectively. After omepra-zole, abdominal feeling scores for the same incremental pressures over MDP were 0.3 ± 0.1, 0.8 ± 0.1, 2.0 ± 0.4, 2.8 ± 0.4, 3.8 ± 0.4, 4.6 ± 0.4, 4.9 ± 0.3, 5.4 ± 0.4, 5.2 ± 0.6, and 5.0 ± 1.0, respectively. A signif- icant decrease in feeling score was observed at intrabag pressures of MDP + 2 mmHg (P = 0.028) and + 4 mmHg (P = 0.013), respectively, after omeprazole. No significant score changes were observed at pres-sures ≥ MDP + 6 mmHg. CONCLUSION:Although the precise mechanisms are undetermined, the present study demonstrated that omeprazole decreases mechanosensitivity to mild gastric distension.  相似文献   
992.
Determination of physicochemical properties of tetrabromobisphenol A   总被引:2,自引:0,他引:2  
Aqueous solubility (Sw), 1-octanol/water partition coefficient (Kow), and vapor pressure of the nonionic form of 2,2',6,6'-tetrabromo-4,4'-isopropylidenediphenol (tetrabromobisphenol A or TBBP-A) were measured. From this, enthalpies of solution and vaporization were estimated. Furthermore, enthalpy of fusion and melting point were measured to estimate subcooled liquid vapor pressure, the infinite dilution activity coefficient, and Henry's law constant. Since TBBP-A is expected to exit in both ionic and nonionic forms at near neutral pH, pH effects on physicochemical properties were also examined. Because of the ionization of TBBP-A, Sw increased by five orders of magnitude, while Kow decreased by eight orders of magnitude. Furthermore, an analytical model based on mass balance and dissociation of TBBP-A was applied to represent the pH dependence.  相似文献   
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PURPOSE: To prospectively compare in vivo hepatic automated volumetry with manual volumetry and measured liver volume. MATERIALS AND METHODS: The study was conducted in accordance with the guidelines of the Institutional Review Board of Kumamoto University (Japan). Patient informed consent was obtained. Preoperative multisection computed tomography (CT) was performed in 35 consecutive patients (21 men, 14 women; mean age, 42.8 years; range, 28-72 years) with hepatic disease awaiting living related liver transplantation. The CT scans covered the entire liver at a section thickness of 2.5 mm. Liver volume was estimated by using both the automated and the manual methods. Actual liver weight was obtained for all patients and was converted to hepatic volume on the basis of a predetermined relationship between actual liver weight and volume. Processing time required for both methods was also recorded. Two-tailed paired t test, correlation coefficient, and Bland-Altman tests were used for statistical analyses. RESULTS: Mean liver weight was 881.7 g +/- 249.8 (standard deviation), and mean measured liver volume was 956.00 cm(3) +/- 280.10. Volumetry performed with the automated and manual methods provided liver volumes of 982.99 cm(3) +/- 301.98 and 937.10 cm(3) +/- 301.31, respectively. There was good correlation between measured and estimated volumes obtained with the automated method (r = 0.792, P < .01). The manual and automated methods required 32.8 minutes +/- 6.9 and 4.4 minutes +/- 1.9, respectively. CONCLUSION: The automated method reduced the time required for volumetry of the liver and provided acceptable measurements.  相似文献   
996.
RATIONALE AND OBJECTIVES: The aim of the study is to investigate the effect of a computer-aided diagnostic (CAD) scheme on radiologist performance in the detection of lung cancers on chest radiographs. MATERIALS AND METHODS: We combined two independent CAD schemes for the detection and classification of lung nodules into one new CAD scheme by use of a database of 150 chest images, including 108 cases with solitary pulmonary nodules and 42 cases without nodules. For the observer study, we selected 48 chest images, including 24 lung cancers, 12 benign nodules, and 12 cases without nodules, from the database to investigate radiologist performance in the detection of lung cancers. Nine radiologists participated in a receiver operating characteristic (ROC) study in which cases were interpreted first without and then with computer output, which indicated locations of possible lung nodules, together with a five-color scale illustrating the computer-estimated likelihood of malignancy of the detected nodules. RESULTS: Performance of the CAD scheme indicated that sensitivity in detecting lung nodules was 80.6%, with 1.2 false-positive results per image, and sensitivity and specificity for classification of nodules by use of the same database for training and testing the CAD scheme were 87.7% and 66.7%, respectively. Average area under the ROC curve value for detection of lung cancers improved significantly (P = .008) from without (0.724) to with CAD (0.778). CONCLUSION: This type of CAD scheme, which includes two functions, namely detection and classification, can improve radiologist accuracy in the diagnosis of lung cancer.  相似文献   
997.
Reported here is the case of a 15‐month‐old boy with costal osteomyelitis due to the bacillus Calmette–Guérin (BCG) vaccine against tuberculosis. Mild complications of this vaccine, such as localized abscess and regional lymphadenitis, are occasionally recognized, but its association with osteomyelitis is extremely rare.  相似文献   
998.
PurposeTo report 10-year outcomes of treating hepatocellular carcinomas (HCCs) by combination therapy of chemoembolization and radiofrequency (RF) ablation.Materials and MethodsCombination therapy was administered in 277 patients with 382 treatment-naïve HCCs. Therapeutic effects, safety, survival rate, and prognostic factors were evaluated.ResultsTumor enhancement disappeared after 466 RF sessions in all tumors, resulting in a complete response rate of 100% (277 of 277) based on modified Response Evaluation Criteria In Solid Tumors. Local tumor progression developed in 15 patients (5.4%; 15 of 277) during the mean follow-up of 44.9 months±29.1 (range, 6.0–134.4 mo). Overall and recurrence-free survival rates were 56.3% (95% confidence interval [CI], 52.5%–60.2%) and 22.5% (95% CI, 19.3%–25.6%) at 5 years and 23.5% (95% CI, 17.7%–29.2%) and 9.3% (95% CI, 6.3%–12.4%) at 10 years. The Child-Pugh class was the only significant prognostic factor detected in both the univariate (P<.001) and the multivariate analyses (hazard ratio, 3.8; 95% CI, 2.5–5.6; P<.001). The 5-year and 10-year overall survival rates were 66.4% (95% CI, 62.0%–70.8%) and 30.6% (95% CI, 23.3%–37.9%) in 210 Child-Pugh class A patients. In addition to the Child-Pugh class, the maximum tumor diameter (≤3 cm vs>3 cm) and the tumor number (single vs multiple) were significant independent factors affecting recurrence-free survival. No death was related to the combination therapy. The major complication rate was 3.2% (15 of 466).ConclusionsRF ablation combined with chemoembolization is a safe and useful therapeutic option for treating HCCs. Prognostic factors detected in this study help to stratify patients who benefit from this combination therapy.  相似文献   
999.

Objectives

Our research group developed new PET scanner with semiconductor detectors for high spatial resolution with low scatter noise. On head and neck cancer (HNC) surgery, FDG-PET may often provide false-positive findings in cervical node involvements. Accordingly, we assessed diagnostic accuracy using this new scanner in the HNC patients as compared with the conventional lutetium oxyorthosilicate (LSO) PET.

Methods

We prospectively studied FDG imaging in 35 HNC patients by both semiconductor PET and LSO-PET. At 60 min after 18F-FDG injection, two PET scans were obtained using both scanners consecutively and in random order. Two nuclear medicine specialists scored FDG abnormalities using 5 point scale system for receiver operating characteristic (ROC) curve analysis.

Results

63 suspected of metastatic or recurrent lesions were evaluated and correlated by the final confirmation by pathological findings or clinical courses (malignant 26/benign 37). Semiconductor PET showed sensitivity of 92.3 % (24/26), specificity of 51.4 % (19/37), and accuracy of 68.2 % (43/63), while LSO-PET showed sensitivity of 84.6 % (22/26), specificity of 16.2 %(6/37), and accuracy of 44.4 % (28/63), respectively. Especially, semiconductor PET accurately diagnosed as true negative in the 13 of 14 lesions only detected by LSO-PET. ROC analyses revealed the diagnostic superiority of semiconductor PET from location of- and area under curve particularly in the study of small (≤10 mm) lesions.

Conclusion

A new novel semiconductor PET scanner can increase diagnostic accuracy with reduction in false positive findings in the HNC patients mainly due to higher spatial resolution and lower noise than the LSO-PET. This new technology can lead to more accurate diagnosis and the more optimal therapeutic tactics in head and neck surgery.  相似文献   
1000.
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