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31.
A case of synchronous squamous cell carcinomas in the soft palate,larynx and esophagus is reported, along with findings of molecular-pathologicalanalysis. A biopsy sample from the aryngeal carcinoma revealedwell differentiated squamous cell carcinoma harboring two pointmutations at codons 144 and 148 of the p53 gene but not at codon299, and more than 50% of the cancer cells showed accumulationof p53 protein immunohistochemically. The esophageal tumor,which was moderately differentiated squamous cell carcinoma,showed immunoreactivity for p53 within the nuclei of 25–50%of cancer cells with a missense mutation at codon 299 but notat codon 144 or 148. This cancer also showed immunoreactivityfor transforming growth factor alpha. On the other hand, thepoorly differentiated squamous cell carcinoma in the soft palateshowed negative immunoreactivity for p53 and no point mutationin exons 5 to 8 of the gene. These results suggest that thethree synchronous squamous cell carcinomas arose as independentevents.  相似文献   
32.
Summary Propionic acidaemia is an inborn error of organic acid metabolism caused by deficiency of propionyl-CoA carboxylase (PCC). Enzyme deficiency can result from mutations in either of the non-identical - and -subunits. We have screened genomic DNA from patients with defects in the -subunit from two ethnic groups (Caucasians and Japanese) and detected three types of mutations in the same exon of the coding sequence of the -subunit: an insertion/deletion that replaces 14 nucleotides with 12 nucleotides of unrelated sequence and eliminates anMsp I site; a 3-bp deletion of a single isoleucine codon immediately proximal to thatMsp I site; and a C T transition in the sameMsp I site. The insertion/deletion was detected only in Caucasian patients in 11 of 34 mutant alleles; the C T transition was found only in Japanese patients in 4 of 12 mutant alleles. Following digestion of genomic DNA byMsp I, both of these mutations were detected on Southern blots by the presence of a 2.7-kbp band; they can be distinguished from one another by allele-specific oligonucleotide hybridization following PCR amplification. These results underscore the independent origin of the mutations in the two populations and suggest a key role of this exon in the -subunit of PCC.  相似文献   
33.
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   
34.
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   
35.
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   
36.
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   
37.
Patients with end-stage renal disease (ESRD) show an inverse association between body mass index and risk of death from cardiovascular disease. Paradoxical epidemiology may suggest some beneficial effects of body fat in ESRD. Because an antiatherogenic adipocytokine adiponectin is increased in uremic plasma, we tested a hypothesis that, in ESRD, plasma adipocytokine profile may be less atherogenic or that the relationship between body fat and adipocytokines may be altered. The subjects were 103 patients with ESRD undergoing hemodialysis and 166 healthy subjects comparable in age and sex. We measured body fat mass by dual-energy x-ray absorptiometry and plasma levels of adiponectin and leptin by enzyme-linked immunosorbent assay. The ESRD group showed a significant increase in plasma adiponectin, leptin, and adiponectin/leptin ratio than the healthy subjects. Although sex and fat mass were significant factors correlating with plasma adiponectin level in the healthy group, none of these were significantly associated with plasma adiponectin in the patients with ESRD. In contrast, leptin showed significant relationships with sex and fat mass regardless of the presence of ESRD. Plasma adiponectin correlated negatively with plasma triglycerides and positively with high-density lipoprotein cholesterol in both healthy and ESRD groups, suggesting that uremic adiponectin retains its actions in favor of its antiatherogenicity. Thus, plasma adipocytokine profile was altered in ESRD, and the effects of body fat and sex on adiponectin were less significant in the patients with ESRD.  相似文献   
38.
Hypothyroidism is associated with increased morbidity from cardiovascular disease, and an increase in serum osteoprotegerin (OPG) has recently been reported to be associated with the severity of coronary heart disease and cardiovascular mortality. The present study was designed to examine whether hypothyroidism causes an increase in serum OPG, and to determine whether levothyroxine (L-T4) replacement therapy might suppress serum OPG levels in hypothyroid patients. Fifty-three hypothyroid patients with chronic thyroiditis and age- and sex-matched normal control subjects were examined for the levels of serum OPG and plasma von Willebrand factor (vWF), a vascular injury marker. Thirty-seven of the hypothyroid patients were further monitored for changes in these markers during 1 year in a euthyroid state induced by L-T4 replacement therapy. Baseline OPG was significantly higher in hypothyroid patients than in normal controls (4.51 +/- 0.50 vs 3.72 +/- 0.23 pmol/l (mean +/- S.E.); P = 0.0182). In multivariate analysis, baseline OPG was significantly associated with baseline levels of TSH (r = 0.280, P = 0.0162) and vWF (r = 0.626, P < 0.0001). During one year of L-T4 replacement therapy, hypothyroid patients showed a significant decrease in OPG levels from 4.35 +/- 0.51 to 3.48 +/- 0.26 pmol/l (P = 0.0166), a level comparable to normal controls. The change in serum OPG levels during L-T4 replacement therapy was significantly and independently associated in a negative fashion with baseline vWF (r = -0.503, P = 0.0014). This study suggested that the severity of hypothyroidism and vascular injury might have important independent roles in increasing the serum OPG level in hypothyroid patients. Furthermore, it was demonstrated that a sustained euthyroid state might have the potential to decrease the serum OPG level in hypothyroid patients and that the degree of vascular injury in the hypothyroid state is independently associated with a decrease in serum OPG during a 1-year normalization of thyroid function.  相似文献   
39.
We measured serum thrombopoietin (TPO) in chronic hepatitis C treated with interferon (IFN). The platelet count before the therapy was 161.9 ×109 ± 64.1 × 109/l, which decreased to 116.3 × 109 ±  48.4 × 109/l 1 week after IFN therapy ( P  <0.01). On the other hand, serum TPO increased from 1.96 ± 0.60 fmol/ml to 2.68 ± 0.69 fmol/ml ( P  < 0.02). Contrary to a recent report that serum TPO was not altered in liver cirrhosis, these data indicate that serum TPO was increased in chronic hepatitis C in response to thrombocytopenia by IFN therapy.  相似文献   
40.
BACKGROUND: The clinical significance of the white blood cell (WBC) count on admission in relation to the duration of ischemia in acute myocardial infarction (AMI) remains unclear. METHODS AND RESULTS: The relationship of the WBC count on admission to myocardial reperfusion was examined in 135 patients with recanalization of an anterior AMI within 6 h of symptom onset. Patients were classified according to the WBC count on admission: Group L (n=75), WBC count <12,000 cells/mm(3) and group H (n=60), WBC count >or=12,000 cells/mm(3). Peak creatine kinase (CK) was higher and impaired myocardial reperfusion, defined as a myocardial blush grade of 0/1, was more frequent in group H than in group L. Among the patients in group H, those with early (3 h) recanalization; however, peak CK and the incidence of impaired myocardial reperfusion were similar in these subgroups of patients. Multivariate analysis showed that WBC count >or=12,000 cells/mm(3) on admission was an independent predictor of impaired myocardial reperfusion in patients with early recanalization (odds ratio 7.9, p=0.04), but not in those with late recanalization. CONCLUSIONS: A higher WBC count may be associated with progression of myocardial damage after recanalization in patients with early recanalization of an anterior AMI.  相似文献   
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