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181.
Narita Y Hatano K Kinoshita F Togawa T Yui N Endo K Koizumi M 《Kaku igaku. The Japanese journal of nuclear medicine》2000,37(3):227-236
PURPOSE: Strontium-89 chloride (89Sr) is a new radiopharmaceutical that provides effective pain relief for metastatic bone lesions, and is expected to be available soon in the palliative management for metastatic bone pain in Japan. Because of relatively long physical half life (50.5 days), 89Sr may affect to the radioactive draining-water system by exceeding the limits of activity concentration for radioactive drain. In this article, the influence of 89Sr use on the radioactive drainage system was simulated. METHODS: The standard tank capacity of drainage and draining frequency was determined from the results of questionnaire carried out for the nationwide medical and research institutes where radioisotope treatment are performed. On the assumption that 89Sr of 148 MBq for one therapy was used twice a week and several common radionuclides were used as the same activity as used at Chiba Cancer Center, the influence of 89Sr was estimated. The calculation was performed using the activity contamination ration into the draining-water system of each radionuclide of 0.01, which was legally determined. RESULTS: The simulation revealed that the sum of the contamination ratios of individual radionuclides exceeded a legal value of 1.0 in standard drainage with the capacity of 5 m3 and 10 m3 and draining frequency of 7 times per year. The actual contamination ratios of common radiopharmaceuticals measured at Chiba Cancer Center ranged from 1/100 to 1/1000 of the legal values. CONCLUSION: It is necessary that the legal value of activity contamination ratios into the draining-water system should be reassessed before starting 89Sr therapy. 相似文献
182.
Shuto T Hirohashi K Ikebe T Mikami S Yamamoto T Kubo S Wakasa K Kinoshita H 《World journal of surgery》2000,24(12):1566-1569
The presence of small additional hepatocellular carcinomas (HCCs) undetectable before hepatic resection is a crucial topic
for hepatic surgeons. We assessed the incidence of pathologically diagnosed multiple HCCs in 267 patients who underwent hepatic
resection for HCC. Ninety-five additional HCC nodules were detected in 72 of the patients (27%). The survival rate of these
72 patients was significant worse than for the 195 with single nodular HCC (p= 0.0013). Twenty-one (22%) were detected before surgery, 29 (31%) during surgery, and 45 (47%) on pathologic examination
after surgery. The mean nodule diameters for each group were 2.1, 1.0, and 0.9 cm, respectively (p < 0.0001). None of the 21 nodules detected before surgery was well differentiated, whereas 30 of the 74 nodules in the other
two groups were well-differentiated. Although the mean nodule diameter of the well-differentiated HCC group was the smallest,
there was no significant difference among the three groups assigned according to tumor differentiation (p= 0.2355). Altogether, 9 of 16 patients with additional nodules detected before surgery (56%) and 49 of 59 with additional
nodules detected during or after surgery (88%) had cirrhosis of the liver. The odds ratio for detecting a new HCC nodule during
or after surgery in the presence of cirrhosis was 5.444 (p= 0.0087). Improvement in the detection of small additional HCC nodules before and during surgery and meticulous follow-up
after surgery are necessary for patients with cirrhosis. For patients without cirrhosis, surgical treatment may be performed
according to the results of preoperative imaging studies. 相似文献
183.
Hiroshi Yoshimura Dipok Kumar Dhar Hitoshi Kohno Hirofumi Kubota Toshiyuki Fujii Shuhei Ueda Shoichi Kinugasa Mitsuo Tachibana Naofumi Nagasue 《Clinical cancer research》2004,10(24):8554-8560
PURPOSE: Angiogenesis plays an important role in a multitude of biological processes including those of tumorigenesis and cancer progression. Hypoxia is the prime driving factor for tumor angiogenesis and the family of hypoxia-inducible factors (HIFs) plays a pivotal role in this process. The role of HIF in tumor angiogenesis has been underscored in different carcinomas but yet to be reported for colorectal carcinomas. EXPERIMENTAL DESIGN: In this study, we examined HIF [HIF-1alpha (HIF1) and HIF-2alpha (HIF2)] expression in 87 curatively resected colorectal carcinoma samples, and the results were correlated with clinicopathological factors, microvessel density, cyclooxygenase 2 expression, and patient prognosis. RESULTS: HIF1 (44.8%) was more frequently expressed than HIF2 (29.9%). Most of the clinicopathological factors representing the tumor aggressiveness were significantly correlated with overexpression of HIF2 but not with HIF1 expression. HIF2 expression had direct correlation with microvessel density and cyclooxygenase 2 expression. and, in contrast, HIF1 expression had a weak but significant inverse correlation in T1 and T2 tumors only. HIF2 expression alone and the combined expression of HIF1 and HIF2 had significant impact on patient survival. In the multivariate analysis, however, only the combined expression of HIF1 and HIF2 remained independently significant. CONCLUSIONS: Taken together, our results suggest that HIF2 expression may play an important role in angiogenesis and that the combined expression of HIF1 and HIF2 may play an important role in tumor progression and prognosis of colorectal carcinomas. Therefore, HIF expression could be a useful target for therapeutic intervention. 相似文献
184.
Kamimura M Itoh H Kinoshita T Yuzawa Y Takahashi J Takaoka K 《Journal of spinal disorders》2000,13(3):267-270
Desmoplastic fibroma is a relatively uncommon tumor and rarely involves the spine. The authors describe a 20-year-old woman with a thoracic epidural desmoplastic fibroma treated by complete resection and posterior spinal fusion. Four years after surgery, neither the tumor nor clinical symptoms have recurred. Thus, complete resection is considered necessary to treat this tumor. 相似文献
185.
BACKGROUND: Uroguanylin, originally isolated from urine, is a new natriuretic peptide. Its plasma level is increased in association with renal impairment and fluid retention in patients with renal diseases. METHODS: Uroguanylin concentrations were measured in patients on hemodialysis (HD, n = 76) and those on continuous ambulatory peritoneal dialysis (CAPD, n = 10) using a sensitive ra- dioimmunoassay for human uroguanylin. RESULTS: Plasma concentrations of immunoreactive (ir)-uroguanylin in the patients on HD and CAPD (212.0 +/- 17.4 and 245.3 +/- 39.5 fmol/ml) were significantly higher than the value for the normal controls (5.0 +/- 0.3 fmol/ml). Plasma ir-uroguanylin levels before the start of regular HD were correlated with predialysis excess weight based on their dry weights (r = 0.33, p < 0.01) and with dialysis duration (r = 0.26, p < 0.05). The plasma levels in patients with HD, for whom high-flux membranes were used, were decreased at the end of regular HD as compared with the prior levels (p < 0.05), but not in those who underwent HD with conventional membranes. CONCLUSION: These findings suggest that the plasma ir-uroguanylin level is related to the patient's volume status as well as renal impairment. Whether the accumulation of uroguanylin has a pathological effect has yet to be determined. 相似文献
186.
187.
188.
Tomoko Ohtsu Hirofumi Fujii Hisashi Wakita Tadahiko Igarashi Kuniaki Itoh Shigeru Imoto Masahiro Kohagura Yasutsuna Sasaki 《Cancer chemotherapy and pharmacology》1998,42(1):1-8
The present study was conducted to compare the pharmacokinetics (PK) of low-dose versus high-dose medroxyprogesterone (MPA)
as a once-daily oral administration. Of 32 patients, all women, enrolled in this PK study, 18 received 600 mg MPA daily and
14 received 1200 mg daily. Detailed PK data were obtained on day 1 and after more than 4 weeks of MPA treatment. In addition,
multiple data for the minimum steady-state concentration (Css min) were analyzed. The MPA serum concentrations were measured
by high-performance liquid chromatography. Wide interpatient variability was found in the PK parameters obtained both on day
1 and after more than 4 weeks. There were no clear relationships between the oral dose and the MPA peak concentration (Cmax),
area under the time versus concentration curve (AUC), or mean Css min. Weight gains of 10% or more were demonstrated more
frequently in the high-dose group (P<0.01). Liver dysfunction (n=5) did not influence the PK of MPA. Five patients demonstrated extremely low AUC and Cmax (<10 ng/ml) values on day 1. Phenobarbital,
dexamethasone and betamethasone were being taken concomitantly with the MPA each by one patient. The serum MPA concentrations
were markedly increased after the discontinuation of phenobarbital in that patient, suggesting a drug interaction. At present
we cannot recommend the high dose of MPA, except in clinical studies, from a PK or a pharmacodynamic points of view.
Received: 2 May 1997 / Accepted: 13 October 1997 相似文献
189.
Diagnosis of chest wall invasion by lung cancer: useful criteria for exclusion of the possibility of chest wall invasion with MR imaging 总被引:3,自引:0,他引:3
Shiotani S Sugimura K Sugihara M Kawamitsu H Yamauchi M Yoshida M Kushima T Kinoshita T Endoh H Nakayama H Kajitani M Wada M 《Radiation Medicine》2000,18(5):283-290
PURPOSE: To compare the accuracy of thin-section CT, conventional static MR imaging (conventional MRI), and breathing dynamic echo planar magnetic resonance imaging (BDEPI) in evaluating lung cancer invasion to the chest wall. MATERIALS AND METHODS: Thin-section CT, conventional MRI, and BDEPI were performed preoperatively in 20 patients suspected of having primary lung cancers adjacent to the chest wall on conventional CT. The results of imaging findings were compared with those of surgical and histopathological findings. RESULTS: All patients were confirmed to have no chest wall invasion after surgery. By thin-section CT, 10 of 20 patients were correctly diagnosed as having no chest wall invasion (50% specificity). Two of the 20 patients were incorrectly diagnosed as having chest wall invasion by conventional MRI and BDEPI (90% specificity). CONCLUSION: When chest wall invasion is suspected on CT scans, static and breathing dynamic MRI are recommended to avoid false positive interpretations. 相似文献
190.
Masuko Sato Hirofumi Aotani Ritsuko Hattori Masahisa Funato 《Pediatrics international》2004,46(3):346-352
BACKGROUND: Diagnostic problems with the criteria of attention deficit hyperactivity disorder (ADHD) in the Diagnostic Statistical Manual, 4th edn, have been identified. The aim of this study was to clarify whether the minor neurological signs test (MNT) the authors had previously reported was a predictor for the criteria of ADHD or hyperactivity disorder (HD) in perinatal risk children at 4-6 years of age and what kind of risk factors related to MNT. METHODS: A total of 136 children discharged from neonatal intensive care units were examined at the age of 4-6 years by a developmental neuropediatrician using both MNT and diagnostic criteria of DSM-IV ADHD/ICD-10 (International Classification of Diseases, 10th edn) HD. SPSS base and professional were used for statistical analysis. RESULTS: On comparison of diagnostic criteria between ADHD (11.0%) and HD (27.5%), the incidence in the same subjects showed significant difference. MNT scores showed significant correlation with criteria of ADHD (P < 0.01) and HD (P < 0.05). Diagnostic validity of MNT for predicting ADHD was demonstrated with 78% sensitivity and 79% specificity. High positive rates on MNT did not show a significant difference between the very low birthweight (VLBW) and non-low birthweight (NLBW) groups. Behavioral outcome with relation to risk factors were analyzed using multiple regression analysis. Apgar 5 in the NLBW group and toxemia of pregnancy and small for gestational age (SGA) in VLBW group were highly correlated with behavioral outcome. CONCLUSIONS: Minor neurological signs test score was a significant predictor for criteria of ADHD and HD. High incidences of positive MNT were suspected in not only VLBW children but also NLBW children and Apgar 5 in NLBW children and toxemia of pregnancy and SGA in VLBW children influenced behavioral outcome. 相似文献