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11.
The modulating effects of caffeine, nicotine, ethanol and sodium selenite on development of N-nitrosobis(2-oxopropyl)-amine (BOP)-initiated pancreatic tumors were investigated. Female Syrian golden hamsters were given s.c. injections of BOP (10 mg/kg body weight) or saline alone once a week for 3 weeks and then administered 2000 p.p.m. caffeine, 25 p.p.m. nicotine, 20% ethanol or 4 p.p.m. sodium selenite in their drinking water for the next 37 weeks. Control animals were given tap water alone after BOP initiation. Only the BOP-treated groups developed pancreatic adenocarcinomas and dysplasias. The multiplicity of pancreatic carcinomas was significantly higher (P less than 0.05) in animals receiving caffeine than in the controls. In addition, caffeine treatment slightly increased the incidence of carcinomas. Nicotine and ethanol also showed tendencies to enhance pancreatic carcinogenesis, although there were statistically no significant differences regarding lesion development. In contrast, sodium selenite administration was associated with a tendency for a decrease in the number of carcinomas and dysplasias. Thus, among these chemicals of obvious significance to human life-style, caffeine enhanced the development of pancreatic tumors when administered during the post-initiation phase in this hamster model.  相似文献   
12.
A rare case of solitary bronchial papilloma was reported. A 57-year-old male was admitted to our hospital because of an abnormal shadow on chest X-ray film which was discovered on regular health check up. Bronchoscopic examination revealed a polypoid tumor which obstructed the left B4 bronchus. Serum concentration of CEA was elevated up to 14 ng/ml by Z-GEL method. Left upper lobectomy was performed. On macroscopic examination of the excised specimen, the tumor arose in B4 bronchus and was yellowish white in color and was cauliflower-like in shape sized 3.5 X 1.5 cm. Histopathologically, the tumor consisted of papillary proliferation of stratified squamous epithelium with ciliated columnar epithelial covering. Findings suggestive of inflammation or malignancy were not observed.  相似文献   
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A total 37 patients with Crohn's disease who underwent intraoperative endoscopy during resection of the affected intestine were evaluated in this study. The average age of the patients at surgery was 23.2 years. The residual lesions in the remaining intestine identified by intraoperative endoscopy were classified according to their pathologic profiles into three groups: A, B and C. In group A, comprising patients with longitudinal ulcers and/or a cobblestone appearance, 10 of 12 patients had recurrence. In 5 of these 10, the residual lesions were exacerbated and 2 required a further operation. The remaining 5 patients showed recurrence at the site of previous anastomosis and 2 of these 5 required additional surgery.In group B, comprising patients with small ulcers, aphthoid ulcers, or scars, and group C, comprising patients with no residual lesions, recurrence was observed in 13 of 16, and 3 of 9 patients, respectively. The recurrent lesions were all found proximal to, or at the site of previous anastomosis. Additional operations were performed on 3 of the group B patients. The findings of this study revealed that recurrence requiring additional surgery is more frequent at the site of anastomosis, regardless of the endoscopic appearance of the residual lesions.  相似文献   
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The effect of a carbon dioxide (CO2) pneumoperitoneum and its duration on rabbit follicular oocytes was assessed by evaluating fertilization and subsequent embryonic development rates. CO2 may cross the plasma membrane and form carbonic acid, which liberates H+, thus lowering the intracellular pH. There were no significant differences in arterial pH and [HCO3-] between CO2 and air treatment groups, whereas arterial pCO2 and pO2 were significantly increased in the CO2 treatment group. We found that the duration of pneumoperitoneum, irrespective of type of gas used, was negatively correlated with success of embryonic development. These findings necessitate that more attention be given to the gas used for creation of a pneumoperitoneum during egg retrieval for in vitro fertilization and an attempt be made to minimize duration of the pneumoperitoneum.  相似文献   
17.
We experienced two cases of left ventricular free wall rupture (LVFWR) following acute myocardial infarction (AMI). Case 1, with the blowout type of LVFWR was initially closed by direct suture, followed by hemostasis using a double patch sealing method (DPS) by which the tear was doubly sealed with large and small bovine pericardium patches to which GRF glue was applied. Case 2 with the oozing type of LVFWR was treated only using DPS. Complete hemostasis was achieved in both cases, and aneurysmal dilatation or constrictive heart failure were not detected by postoperative left ventriculography. Therefore, DPS may be useful for treating LVFWR following AMI.  相似文献   
18.
Correction of cryptotia using a subcutaneous pedicled flap   总被引:1,自引:0,他引:1  
Cryptotia is a relatively common deformity of the ear among orientals. Although many methods for correcting this deformity have been reported, there is no one perfect method. We have developed a method using a subcutaneous pedicle flap raised from the retroauricular region, where relative abundance of skin exists. We have treated 9 ears of 7 patients by the method reported herein. Results are satisfactory in all cases.  相似文献   
19.
Single photon emission computed tomography (SPECT) with N-isopropyl-p-[123I]-iodoamphetamine was performed twice at different times in 18 children suffering from partial seizures to evaluate the time-course changes of the hemodynamics in the focal region. Comparison of the 2 SPECT images revealed that a decreased regional cerebral blood flow (CBF) in the first was normalized in 4 cases (22.2%) and contracted in 7 cases (38.9%). The region of decreased blood flow in the second was contralateral to that in the first in 1 case (5.6%) and unchanged in 6 cases (33.3%). Most of the normalized and contracted cases were those in which clinical seizures disappeared and the EEG findings were normalized. In these cases which responded to treatment, the decreased regional CBF was also found to be improved. Repeated SPECT appears to be useful for evaluating the therapeutic efficacy. On the other hand, most of the unchanged cases were those in which clinical seizures were frequent or uncontrolled, or which persistently showed the abnormalities in their EEG. SPECT was considered to reflect well the conditions of the epileptic foci. These results indicate that repeated SPECT for observing the time-course changes of the regional CBF represents a useful technique with can be applied in evaluating the therapeutic efficacy or deciding the time to discontinue treatment and for pathogenetic elucidation of the epileptic foci.  相似文献   
20.
Glutathione peroxidase (GSH-Px) is an important selenium-containing enzyme which protects cells from oxidative damage. Two hybridoma clones (GPX-121 and GPX-347), producing mouse IgG1 monoclonal antibodies specific for GSH-Px, were established. Immunoblot analysis revealed that GPX-347 was specific for human GSH-Px, while GPX-121 cross-reacted with human, rat, mouse and rabbit GSH-Px. Correlation between GSH-Px content and its enzymatic activity was investigated in erythrocytes of 76 humans and in human lung adenocarcinoma PC-9 cells by using a sandwich type ELISA. The results indicated that GSH-Px activity was expressed higher than expected from GSH-Px content especially in the range of low GSH-Px concentration. PC-9 cells selenium depleted medium did not stain but the cytoplasm of PC-9 cells grown in medium supplemented with selenium stained strongly.  相似文献   
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