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51.
Pharmacokinetic and clinical studies on cefmenoxime (CMX) in neonates and infants were conducted. 1. CMX 20 mg/kg was administered by intravenous bolus injection to 6 neonates (with ages 2 to 20 days) and 5 infants (with ages 36 to 107 days) and its serum concentration and urinary excretion rates were determined. In the neonates, serum concentrations of CMX after intravenous administration reached peak levels of 48.2 to 90.7 micrograms/ml (mean 70.4 +/- 14.3 micrograms/ml) in 1/4 hour, then declined with half-lives of 1.27 to 5.19 hours (mean 2.28 +/- 1.56 hours), and were 3.6 to 16.9 micrograms/ml (mean 8.3 +/- 6.0 micrograms/ml) at 6 hours. In the infants, serum concentrations at 1/4 hour were 67.5 to 111.0 micrograms/ml (mean 95.5 +/- 18.0 micrograms/ml); half-lives were 0.64 to 0.94 hour (mean 0.81 +/- 0.13 hour); and the serum concentrations at 6 hours were 0.2 to 1.1 micrograms/ml (mean 0.7 +/- 0.4 micrograms/ml). Mean peak serum concentrations in the neonates tended to be lower than those in the infants, but higher than those in children. Regarding the age differences of serum concentrations due to age in the neonates, their peak levels tended to be lower in younger ones. Half-lives were shorter in older subjects and, in early infancy, approached values observed in children. Urinary recovery rates in the first 6 hours after intravenous administration ranged from 43.6 to 87.5% (mean 61.6 +/- 14.6%) in the neonates and from 52.1 to 90.8% (mean 78.0 +/- 15.1%) in the infants. Thus, recovery rates were high even in younger subjects and tended to be higher in older subjects. 2. CMX was administered to 27 neonates and 4 infants to investigate its clinical effect, bacteriological effect and side effects. Clinical efficacy ratings of the drug in 19 neonate cases that could be evaluated (1 with purulent meningitis, 2 with suspected septicemia, 1 with acute bronchitis, 12 with acute pneumonia, 1 with impetigo, 1 with periumbilical abscess and 1 with acute pyelonephritis) were "excellent" in 14 cases, "good" in 4, and "poor" in 1. The efficacy rate covering "excellent" and "good" was 94.7%. In 4 infants (2 with acute pneumonia, 1 with periumbilical abscess and 1 with acute pyelonephritis), "excellent" was obtained in 2 cases and "good" in 2 cases. Thus, all the cases showed "good" or higher ratings. Bacteriologically, 1 strain of Staphylococcus aureus and 3 strains of Escherichia coli in neonates were eradicated while, in infants, 1 strain of S. aureus persisted but 1 of E. coli was eradicated.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
52.
Patients with acute (2,569) and chronic (957) leukemia diagnosedat 19 institutes took part in the study on the "MultidisciplinaryTreatment of Leukemia" between 1971 and 1985 and were investigatedretrospectively. By dividing the 15 years into three five-yearperiods, we were able to compare patient ratios in the differentperiods. The proportions of acute to chronic leukemia casesshowed no obvious change; however, the proportions of casesdiagnosed as acute lymphocytic leukemia in acute leukemia showeda significant increase. The main chemotherapeutic drugs usedduring the three time periods were cytarabine or its analogues,the anthracyclines, 6-mercaputopurine and prednisolone, againstacute myelogenous leukemia, and the vinca alkaloids, prednisoloneand the anthracyclines against acute lymphocytic leukemia. Therate of complete remission from acute myelogenous leukemia mademarked progress, from 45.1% during 1971–1975 to 62.3%during 1981–1985, but that of acute lymphocytic leukemiashowed no significant progress, being 65% during 1971–1975and 69.7% during 1981–1985. The durations of remission,however, and the survival times for patients with acute lymphocyticleukemia, as well as for those with acute myelogenous leukemia,became significantly longer over the three periods. Median survivaltimes from chronic myelocytic leukemia were 37–40 mo inall three periods, showing no progress. There was a better prognosisin cases of chronic myelocytic leukemia with, than without,Philadelphia chromosome. Except for a low incidence of chroniclymphocytic leukemia in Japan, adult leukemia patients' characteristicsand prognoses seem to be almost the same in Japan as in theU.S.A. and Europe.  相似文献   
53.
54.
Malignant pleural effusion (PE) is one of the poor prognostic factors in non-small cell lung cancer (NSCLC), and the detailed mechanism of the malignant PE formation is not fully elucidated. Recently, CXCR4, a receptor for chemokine stromal-derived factor-1alpha (SDF-1alpha) that can induce chemotaxis of cells, was reported to be expressed on NSCLC. In this study, we hypothesized that the SDF-1alpha/CXCR4 axis may be involved in the dissemination of malignant cells into pleural space, and investigated its expression, function, and signaling pathway using NSCLC cell lines and clinical samples from 43 patients with NSCLC with malignant PE. We found functional expression of CXCR4 on NSCLC cell lines, and also found that SDF-1alpha could induce migration via phosphatidylinositol 3 (PI-3) kinase- and p44/42 mitogen-activated protein kinase-dependent manner. The SDF-1alpha levels in malignant PE were significantly higher than those in transudate PE and showed a significant positive correlation with PE volumes. The sensitivity and specificity for prediction of recurrence of malignant PE was 61.5% and 83.3%, respectively (cutoff SDF-1alpha = 2,500 ng/ml), and better than those using pH of PE. Cancer cells in malignant PE expressed CXCR4, and mesothelial cells of the pleura stained positive for SDF-1alpha. The SDF-1alpha/CXCR4 axis is involved in the dissemination of NSCLC cells into pleural space.  相似文献   
55.
56.
The aim of this study was to determine the in-phantom thermal neutron distribution derived from neutron beams for intraoperative boron neutron capture therapy (IOBNCT). Gold activation wires arranged in a cylindrical water phantom with (void-in-phantom) or without (standard phantom) a cylinder styrene form placed inside were irradiated by using the epithermal beam (ENB) and the mixed thermal-epithermal beam (TNB-1) at the Japan Research Reactor No 4. With ENB, we observed a flattened distribution of thermal neutron flux and a significantly enhanced thermal flux delivery at a depth compared with the results of using TNB-1. The thermal neutron distribution derived from both the ENB and TNB-1 was significantly improved in the void-in-phantom, and a double high dose area was formed lateral to the void. The flattened distribution in the circumference of the void was observed with the combination of ENB and the void-in-phantom. The measurement data suggest that the ENB may provide a clinical advantage in the form of an enhanced and flattened dose delivery to the marginal tissue of a post-operative cavity in which a residual and/or microscopically infiltrating tumour often occurs. The combination of the epithermal neutron beam and IOBNCT will improve the clinical results of BNCT for brain tumours.  相似文献   
57.
58.
Relationship between SIRS and CARS in the pathologic condition of acute pancreatitis was discussed. SIRS promotes excessive inflammatory reaction and CARS induces the susceptibility to infection. Both conditions can develop into organ failure in acute pancreatitis. Hence, countermeasures for both conditions are mandatory in the care of patients with acute pancreatitis.  相似文献   
59.
Somatic mitochondrial mutation in gastric cancer.   总被引:11,自引:1,他引:11       下载免费PDF全文
Likely hot spots for mutations are mitochondrial sequences as there is less repair and more damage by carcinogens compared with nuclear sequences. A somatic 50-bp mitochondrial D-loop deletion was detected in four gastric adenocarcinomas. The deletion included the CSB2 region and was flanked by 9-bp direct repeats. The deletion was more frequent in adenocarcinomas arising from the gastroesophageal junction (4/32, 12.5%) compared with more distal tumors (0/45). Topographical analysis revealed the absence of the deletion from normal tissues except in focal portions of smooth muscle in one case. In two cases, apparent mutant homoplasmy was present throughout two tumors, including their metastases. In the two other cases, the mutation was present in only minor focal portions ( < 5%) of their primary tumors. These findings document the presence of somatic mitochondrial alterations in gastric cancer, which may reflect the environmental and genetic influences operative during tumor progression.  相似文献   
60.
To the significance of basophilia in haematopoietic disorders, six draw attention to cases have been analyzed. Associated diseases included acute myelogenous leukaemia (AML-M2, M3, M4, and M6), refractory anaemia with excess of blasts (RAEB) and RAEB in transformation (RAEB-T). Two AML cases (M2, M6) were preceeded by myelodysplastic syndromes (MDS). All patients showed greater than 3% basophilia in peripheral blood and bone marrow. Basophils were identified successfully by metachromatic staining with toluidine blue in all cases. Three patients (M3, M4, RAEB) presented with lymphadenopathy, suggesting an association with extramedullary involvement. Neutrophil alkaline phosphatase (NAP) activity was significantly reduced in four patients with AML (M2, M3, M4) and RAEB-T. The clinical course was generally unfavourable characterized by short remission duration or disease progression except for the patient with RAEB. Haemorrhage was the main cause of death rather than infection. Cytogenetic analysis revealed unique abnormalities involving chromosomes 3q21, 5q31, and 17q11 where the genes for some haematopoietic growth factors or their receptors are located, in addition to t(6;9) and t(15;17).  相似文献   
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