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Purpose:It has been reported previously that intravenously administered gadolinium-based contrast agent (GBCA) leaks into the subarachnoid space around the cortical veins at 4 h after injection in all old people over 37 years, but not in younger people up to 37 years of age in 3D-real IR images. The purpose of this study was to investigate whether there was a strict threshold of 37 years of age for the leakage of the GBCA into the subarachnoid space.Methods:The subjects included 190 patients, that were scanned for 3D-real IR images at 4 hours after intravenous injection of GBCA as a diagnostic test for endolymphatic hydrops. The patient’s age ranged from 14 to 81 years. Two experienced neuroradiologists evaluated the images to determine whether the GBCA leakage around the cortical veins was positive or negative. Any discrepancies between the two observers were discussed and a consensus was obtained.A Mann–Whitney U test and receiver operating characteristic (ROC) curve analysis were used to compare the positive and the negative group and to set the age cut-off value for the prediction of GBCA leakage.Results:The GBCA leakage around the cortical veins was negative in 35 patients and positive in 155 patients. The average age was 33 ± 11 years in the negative group, and 55 ± 12 years in the positive group (P < 0.01). In the ROC analysis for the age and leakage of the GBCA, an area under the curve was 0.905 and the cut-off age was 37.317 years (sensitivity of 0.942 and specificity of 0.771).Conclusion:Intravenously administered GBCA leaks into the subarachnoid space around the cortical veins in most patients over 37 years of age. However, it should be noted that it can be found occasionally in patients under 37 years of age.  相似文献   
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Background: Gastrointestinal stromal tumors (GIST) are one of the most common mesenchymal tumors of the gastrointestinal tract. GIST are defined by positive immunohistochemical staining for KIT or CD34 and thus are generally diagnosed after surgery. Because small GIST are rarely diagnosed before surgery, the clinical course of these small tumors is not clear. The aim of the present study was to follow changes in size and configuration of small GIST that were pathologically confirmed using endoscopic ultrasonography‐guided fine‐needle aspiration biopsy (EUS‐FNAB). Methods: Between July 1997 and December 2003, 16 tumors in 16 patients (10 men and 6 women) with an immunohistochemical diagnosis of GIST were regularly followed in our hospital. The median patient age when EUS‐FNAB was performed was 62 years (range 26–82 years) and the median follow‐up period was 4.9 years (range 0.5–9.6 years). Results: Fourteen tumors showed no remarkable changes in size and shape during follow up compared with the initial diagnosis. Two tumors enlarged: one tumor approximately doubled its diameter in 8 years and the other tumor increased from 1.8 cm at diagnosis to up to 10 cm after only 2 years. Doubling time of the latter tumor was calculated as 3.1 months. Conclusions: We conclude that EUS‐FNAB might be a good modality for final diagnosis of GIST without surgery, and that GIST without rapid growth on follow up can be endoscopically followed.  相似文献   
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OBJECTIVES: To reveal the frequency and the clinical characteristics of dystrophic calcification that occurs in children with juvenile dermatomyositis, multi-center analysis was constructed. METHOD: Fifty children with JDM were enrolled, and 14 of them (28.0%) were complicated with calcinosis. Clinical symptoms and laboratory tests at onset, initial therapy and disease course were compared in children with and without calcinosis. RESULTS: The mean age of the onset of calcinosis was 4.78 +/- 3.33 years, and it was younger than those of children without calcinosis (8.66 +/- 3.85 years) (P = 0.0017). No differences of clinical manifestation except Gower's sign were observed. The frequency of positive anti-nuclear antibody was 7.1% in children with calcinosis and 52.9% without calcinosis (P = 0.0112). The initial therapy of methylprednisolon pulses gave no effects on prognosis of calcium deposition. The calcinosis appeared in 1.56 +/- 1.91 year after the onset of the disease. The various types of calcium deposition including large tumorous clumps, subcutaneous plaques or nodules, sheet-type calcification were deserved. They appeared over knee joints (64.3%), elbow joint (64.3%), and hip processes (50.0%). Calcinosis affecting the subcutaneous tissues frequently resulted in painful superficial ulceration of the overlying skin (42.9%), local infection (50.0%), and limitation of joint movement (14.3%). Although aluminum phosphate was effective in 2 children among 7, no other effective treatment was recommended. In 5 cases, surgical removal of tumorous clumps was operated. Thus, juvenile dermatomyositis is frequently complicated with calcinosis. This type of calcinosis was found to be unlikely to resolve completely, and resulted in severe disability in children.  相似文献   
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Laparoscopic cholecystectomy and time-course changes in renal function   总被引:13,自引:3,他引:10  
Background: Recently, the retraction method has been used to reduce intraabdominal pressure (IAP) during laparoscopic surgery. The purpose of this study was to determine the serial changes in renal function during laparoscopic cholecystectomy (LC) using the retraction method. Methods: Urine output, effective renal plasma flow (ERPF), and glomerular filtration rate (GFR) were measured serially in seven patients who underwent LC with 12 mmHg pneumoperitoneum (High-IAP group) and five who underwent LC using the retraction method with 4 mmHg pneumoperitoneum (Low-IAP group). Results: Urine output, ERPF, and GFR were decreased during pneumoperitoneum in the High-IAP group, whereas no significant changes in any of these parameters were observed in the Low-IAP group. Conclusions: Our findings demonstrate that reduction of IAP to 4 mmHg using the retraction method prevents the transient renal dysfunction caused by prolonged 12 mmHg pneumoperitoneum during LC, suggesting that the retraction method reduces the risk of perioperative renal dysfunction during laparoscopic surgery. Received: 26 March 1996/Accepted: 27 July 1996  相似文献   
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We assessed the efficacy of a government-sponsored mass protection program in Osaka, Japan, for perinatal HBV infection in infants born to HBeAg positive HBV carrier mothers. We also evaluated the impact of optional follow-up procedures in such infants, including an evaluation of anti-HBs response and a booster dose of HBV vaccine for poor responders. The results demonstrated that this mass protection program protected 94.4% of the infants from perinatal HBV infection in the Osaka area. However, the proportion of infants with an unprotective level of anti-HBs was higher in the standard group than in the follow-up group both at 1.0 and 1.5 years of age, which was also the case for HBV events. Furthermore, the present study showed that a booster dose of vaccine in poor responders was very effective in promoting an anti-HBs response. In conclusion, we recommend that a follow-up blood test to confirm a response of anti-HBs to HBV vaccine should be performed at 4–8 weeks after the third injection of HBV vaccine in infants born to HBeAg positive HBV carrier mothers. We also recommend that a booster injection of HBV vaccine should be immediately given to poor responding infants who otherwise are at a considerable risk of developing HBV infection in late infancy.  相似文献   
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Rats, initiated to self-administer 10% (v/v) ethanol in an operant situation using the sucrose-fading procedure, received bilateral n. accumbens microinjections of d-amphetamine prior to operant sessions. Doses of 4 micrograms, 10 micrograms and 20 micrograms/brain were administered and some animals also received a 4 microgram/brain dose of LY171555. Three different effects were observed: increased, decreased and no change in total session responding. There was no clear relation between injection area in the n. accumbens and type of effect observed. For either an increase or decrease in total session responding, momentary response rates were decreased. Both d-amphetamine and LY171555 produced similar results. The data support the hypothesis that dopamine in the n. accumbens is involved with ethanol reinforced operant responding but in a complex manner.  相似文献   
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Norfloxacin, a new quinolinecarboxylic acid derivative, was administered to 30 male patients with gonococcal urethritis at a daily dose of 600 mg for 7-21 days. The clinical response was evaluated after administration of 7 days as excellent; Negative culture of N. gonorrhoeae. WBC less than 3/hpf in first voided urine sediment, good; Negative culture, WBC greater than or equal to 3/hpf, and poor; Positive culture. The result was excellent in 14 cases and good in 16 cases. No subjective side effects were observed. The minimum inhibitory concentration (MIC) distribution against the clinically isolated 30 strains of N. gonorrhoeae ranged from 0.0096 micrograms/ml to 0.34 micrograms/ml. Seven of thirty strains were resistant to ABPC. The MIC of these 7 strains ranged from 0.018 micrograms/ml to 0.18 micrograms/ml. Seven cases with ABPC resistant strains had a similar clinical response to other cases. Twelve patients (40%) developed post gonococcal urethritis for 7-14 days after treatment. Clinical observation of this series suggests that a 7 day therapy of Norfloxacin for the patients with gonococcal urethritis is sufficiently effective and that treatment should be changed to other antibacterial agents in the case of post gonococcal urethritis, since continuous administration for more than 7 days of Norfloxacin is not so effective.  相似文献   
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