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1.
We experienced a case of mediastinal lipoma, which is considered to be a relatively rare disease. A 3-year-old girl was referred to Gifu University hospital because of fever and an abnormal shadow on her chest X-ray. The chest X-ray clearly showed a well-delineated tumor shadow which seemed to oppress the diaphragm and the right atrium in the right lower lung area. A computed tomogram (CT) of the chest showed a homogeneous mass localized on the right diaphragm and adjoining the right anterior chest wall and heart. The mass showed a fat density measuring about-100 HU. Magnetic resonance imaging (MRI) showed a high-intensity mass which was almost the same level as the subcutaneous fat on both the T1-weighted and T2-weighted images. Thoracotomy was performed and a fatty tumor was found. It arose from the right side of the pericardium and adjoined the diaphragm, the anterior chest wall, and the thymus. There was no adhesion between the tumor and the surrounding organs. It was resected easily and its contents were yellowish and homogeneous. The patient made an uneventful recovery and was discharged 10 days after the operation. Light microscopy showed a lipoma consisting of mature adipose tissue and no malignancy was found.  相似文献   
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The acid-catalyzed condensation of formaldehyde and diphenyl sulfide was carried out in benzene in the presence of p-toluene sulfonic acid. From the products, four poly(methylene diphenyl sulfides) of the following structures were isolated.   相似文献   
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Three cases of pulmonary hypertension caused by tumor emboli to the lungs are described. Two of the three cases had a clinical diagnosis of pulmonary thromboembolism until surgical embolectomy, and the other had a diagnosis of primary pulmonary hypertension. Autopsy disclosed chondrosarcoma, choriocarcinoma and gastric cancer as the primary tumors, respectively. Pulmonary vascular obstruction due to tumor embolism leading to pulmonary hypertension is a previously rare clinical entity, and obstructed pulmonary vessels are believed to tend to be small vessels. We compared the autopsy and radiological findings and concluded that pulmonary tumor embolism involved not only the small peripheral arteries but also the segmental and/or lobar arteries.  相似文献   
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The adsorption of trimethylammonium glycol chitosan iodide (TGCI) on Dowex CCR-2 resin was investigated at different pH values and resin weights. The concentration of Na+ or Ca2+ ions, released by the ion exchange reaction with TGCI, was measured by inductively coupled plasma spectroscopy. It was found that the amount of the released ions is comparable to that of the absorbed TGCI. This indicates that the salt-linkage formation of carboxylate ions of the exchanger with ⊕N(CH3)3-groups in TGCI follows a stoichiometric relationship. This result is discussed in connection with the form of the polymer layer adsorbed on the solid surface.  相似文献   
6.
Kinetic studies on the acid-catalyzed reaction of formaldehyde with diphenyl sulfide (DPS) were carried out in acetic acid in the presence of sulfuric acid. The rate of the initial stage of the reaction was found to be in agreement with the following equation. The relative rates of diphenyl sulfide and its homologous compounds in the reaction with formaldehyde gave a good correlation with BROWN -OKAMOTO 's σ values and a large ρ value. The polar effects of substituents of the substituted diphenyl sulfides on the rates were found to be considerably large. From these results a plausible mechanism of the reaction has been deduced.  相似文献   
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The efficiency of flow through the retinal pigment epithelium (RPE) was calculated by studying the postoperative course of the subretinal fluid after nondrainage surgery of rhegmatogenous retinal detachment. In ten eyes of ten patients the preoperative volume of the subretinal fluid, area of the RPE participating in resorption of the fluid, elapsed time until resorption of the fluid, and efficiency of the flow were studied using B-scan ultrasonography. The flow through the RPE was 261 l/cm2 per day and could drain more than 50% of the vitreous volume to the choroidal circulation. These data coincide well with early reattachment of neural retina in nondrainage surgery. No statistically significant difference in this flow was seen between young and old patients.  相似文献   
9.
Summary The depressant effect of interferon- on drug metabolizing activity in the liver has been investigated in 12 patients with chronic active hepatitis B. 7-methoxy-coumarin (7-MC) O-demethylase and 7-ethoxycoumarin (7-EC) O-deethylase, in specimens obtained by liver biopsy, were measured before and after interferon treatment. 7-MC and 7-EC O-dealkylase activity were significantly reduced after interferon treatment, from 13.4 to 9.24 nmol·g–1 liver·min–1, and from 3.22 to 2.16 nmol·g–1 liver·min–1, respectively. The magnitude of the fall varied widely between individual patients. The study provides the first direct evidence that interferon- can impair the activity of drug metabolizing enzymes in the human liver.  相似文献   
10.
We have developed a new type of drug delivery system (DDS) comprising a complex of porous hydroxyapatite (HAP) with the anticancer drug doxorubicin hydrochloride (DOX) and the glutathione inhibitor buthionine sulfoximine (BSO) (DOX and BSO-HAP complex). We then studied the antitumour effect of DOX and BSO-HAP combined with 44 degrees C hyperthermia for 40 min. It was found that in mice this combined treatment suppressed the growth of sarcoma 180 in terms of tumour volume to 36% in comparison viith mice given plain HAP, and was more effective than HAP + hyperthermia or DOX- and BSO-HAP. These results were also confirmed by histological observation.  相似文献   
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