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121.
A 72-year-old Japanese woman, suffering from squamous cell lung cancer with brain metastasis, underwent 2 courses of combination chemotherapy, consisting of cisplatin and vindesine. Although both the primary tumor and the brain metastasis regressed markedly, she developed left ocular pain with blurred vision. An abnormal mass was found in the left iris, and cytologic examination of the aqueous aspirate revealed a few malignant cells, which, when examined by electron microscopy, were considered to be derived from squamous cell carcinoma of the lung.  相似文献   
122.
The WT1 tumor suppressor gene was examined for mutations in a panel of 44 patients with myelo-dysplastic syndromes (MDS) including acute myelogenous leukemias (AML) secondary to MDS, using polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP) analysis and sequencing analysis. A WT1 mutation was detected in one out of 17 cases of AML secondary to MDS. This mutation exists upstream of the zinc finger region and is predicted to produce a truncated WT1 protein lacking the zinc finger region. No mutations were detected in 27 MDS patients who had not progressed to AML. This is the first report of analysis for WT1 mutations in a large number of MDS patients, suggesting that WT1 mutations are uncommon in MDS. Abnormalities in this gene may, however, contribute to a small proportion of cases showing progression from MDS into AML.  相似文献   
123.
Fexofenadine is a selective, nonsedating H(1)-receptor antagonist approved for symptoms of allergic conditions, which is mainly excreted into feces via biliary excretion. The purpose of this study is to investigate its pharmacokinetics in mice and rats to determine the role of P-glycoprotein (P-gp) in its biliary excretion. In mice, biliary excretion clearance (17 ml/min/kg) accounted for almost 60% of the total body clearance (30 ml/min/kg). Comparing the pharmacokinetics after intravenous and oral administration indicated that the bioavailability of fexofenadine was at most 2% in mice. Knockout of Mdr1a/1b P-gp did not affect the biliary excretion clearance with regard to both plasma and liver concentrations, whereas the absence of P-gp caused a 6-fold increase in the plasma concentration after oral administration. In addition, the steady-state brain-to-plasma concentration ratio of fexofenadine was approximately 3-fold higher in Mdr1a/1b P-gp knockout mice than in wild-type mice. Together, these results show that P-glycoprotein plays an important role in efflux transport in the brain and small intestine but only a limited role in biliary excretion in mice. In addition, there was no difference in the biliary excretion between normal and hereditarily multidrug resistance-associated protein 2 (Mrp2)-deficient mutant rats (Eisai hyperbilirubinemic rats) and between wild-type and breast cancer resistance protein (Bcrp) knockout mice. These results suggest that the biliary excretion of fexofenadine is mediated by unknown transporters distinct from P-gp, Mrp2, and Bcrp.  相似文献   
124.
Tahara RW  Lackner RP  Graver LM 《American journal of surgery》2000,180(6):488-91; discussion 491-2
BACKGROUND: The role of surgical staging of patients with non-small cell lung cancer (NSCLC) continues to evolve. This report describes our findings utilizing routine cervical mediastinoscopy in the evaluation of peripheral T1 (<3 cm) lung tumors. METHODS: Retrospectively 30 patients with peripheral T1 lesions and CT scans negative for pathologic adenopathy were identified over a 3-year period. Cervical mediastinoscopy was performed prior to VATS/thoracotomy during the same operative session. RESULTS: Mediastinoscopy was performed in 29 of 30 patients. For patients with malignancy (27 of 30), 3 of 27 (11%) had mediastinoscopy positive for malignancy and no further resection performed. Overall the subgroup of patients with bronchogenic carcinomas had positive mediastinal involvement identified in 5 of 24 (21%) after mediastinoscopy or complete resection. CONCLUSION: A significant number of patients with small peripheral lung cancers harbor radiographically occult lymph node involvement. Mediastinoscopy facilitates identification of patients with regionally advanced disease prior to resection, allowing neoadjuvant therapy and avoiding unnecessary resections.  相似文献   
125.
The association between congenital duodenal obstruction and concomitant choledochal cyst has not been reported, although duodenal obstruction is known to be associated with many other anomalies. The authors describe 2 patients with choledochal cyst with duodenal obstruction. In 1 patient, a diverticulum type of choledochal cyst was found within an annular pancreas. Cyst excision, choledochojejunostomy, and side-to-side duodeno-duodenostomy were performed. The other patient showed separated duodenal atresia and other multiple anomalies including imperforate anus. A choledochal cyst was noted at the time of duodeno-duodenostomy and sigmoid colostomy. Cyst-enterostomy was performed at the age of 8 months, but the patient died of multiple anomalies. Intraoperative cholangiography indicated an anomalous pancreatobiliary ductal junction (APBDJ). In both patients the bile in the cyst contained high levels of amylase, suggesting the presence of an APBDJ. An APBDJ is considered to play an etiologic role in the development of the choledochal cysts associated with duodenal obstruction.  相似文献   
126.
Guidelines for treatment of ulcerative colitis in children   总被引:2,自引:0,他引:2  
This paper introduces the guidelines for treatment of ulcerative colitis in children, created by the working group of the Japanese Society for Pediatric Gastroenterology, Hepatology and Nutrition (Chair: Yuichiro Yamashiro) and the Japanese Society for Pediatric Inflammatory Bowel Disease (IBD) (Chair: Akio Kobayashi). The ideas of the working group, with regard to the fundamental differences in medical treatment between children and adults, included: (1) for children, intensive medical treatment including appropriate systemic management is important during the acute phase of illness. (2) Treatment with steroids, which can cause growth disturbances, should not be continued for long periods of time. (3) Pulsed steroid therapy, selective removal of blood cells, and intravenous infusion of cyclosporin should be included in the therapeutic option for severe and fluminant cases.  相似文献   
127.
Although exfoliative dermatitis (erythroderma) secondary to malignancy is commonly associated with lymphomas or leukemias, coincident gastrointestinal (GI) malignancy and erythroderma is rare. The authors recently encountered a patient with gallbladder carcinoma presenting as erythroderma. A 77-yr-old Japanese man presented with a 3-mo history of erythematous eruptions with pruritus over almost the entire body. After confirming the diagnosis of erythroderma, asymptomatic gallbladder carcinoma was found. Further investigations detected no malignancies in other organs. An extended cholecystectomy was performed. Histologic examination of resected specimens revealed poorly differentiated adenocarcinoma with negative resection margins. The eruptions with pruritus resolved within 1 wk after the operation. This is the first report, to our knowledge, of coincident biliary malignancy and erythroderma. The experience of the current patient suggests that erythroderma secondary to GI malignancy may resolve spontaneously after curative resection of the tumor.  相似文献   
128.
Long-term toluene abuse causes a variety of psychiatric symptoms. However, little is known about abnormalities at the neurochemical level in the living human brain after long-term exposure to toluene. To detect neurochemical changes in the basal ganglia of subjects with a history of long-term toluene use, proton magnetic resonance spectroscopy (1H MRS) was performed in 12 abstinent toluene users and 13 healthy comparisons with no history of drug abuse. N-acetylaspartate (NAA), creatine plus phosphocreatine (Cr + PCr), choline-containing compounds (Cho), and myo-inositol (MI) levels were measured in the left and right basal ganglia. The Cho/Cr + PCr ratio, a marker of membrane metabolism, was significantly increased in the basal ganglia of toluene users in comparison to that of the control subjects. Furthermore, the increase in the Cho/Cr + PCr ratio was significantly correlated with the severity of residual psychiatric symptoms. These findings suggest that long-term toluene use causes membrane disturbance in the basal ganglia, which is associated with residual psychiatric symptoms that persist even after long-term abstinence from toluene use.  相似文献   
129.
The antitumor 3'-ethynyl nucleosides, 1-(3-C-ethynyl-beta-D-ribopentofuranosyl)cytosine (ECyd) and 1-(3-C-ethynyl-beta-D-ribopentofuranosyl)uridine (EUrd), are potent inhibitors of RNA polymerases and show excellent antitumor activity against various human solid tumors in xenograft models. ECyd is being investigated in phase I clinical trials as a novel anticancer drug possessing a unique antitumor action. ECyd and EUrd require the activity of uridine/cytidine kinase (UCK) to produce the corresponding active metabolite. The UCK family consists of two members, UCK1 and UCK2, and both UCKs are expressed in many tumor cells. It was unclear, however, whether UCK1 or UCK2 is responsible for the phosphorylation of the 3'-ethynyl nucleosides. We therefore established cell lines that are highly resistant to the 3'-ethynyl nucleosides from human fibrosarcoma HT-1080 and gastric carcinoma NUGC-3. All the resistant cell lines showed a high cross-resistance to ECyd and EUrd. As a result of cDNA sequence analysis, we found that UCK2 mRNA expressed in EUrd-resistant HT-1080 cells has a 98-base pair deletion of exon 5, whereas EUrd-resistant NUGC-3 cells were harboring the point mutation at nucleotide position 484 (C to T) within exon 4 of UCK2 mRNA. This mutation was confirmed by genome sequence analysis of the UCK2 gene. Moreover, the expression of UCK2 protein was decreased in these resistant cells. In contrast, no mutation in the mRNA or differences in protein expression levels of UCK1 were shown in the EUrd-resistant HT-1080 and NUGC-3 cells. These results suggest that UCK2 is responsible for the phosphorylation and activation of the antitumor 3'-ethynyl nucleosides.  相似文献   
130.
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