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81.
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Interferon-gamma (IFN-gamma) transgenic mice strongly express IFN-gamma in the liver and develop chronic hepatitis. Furthermore, hepatocyte apoptosis was shown by the TdT-mediated dUTP-biotin nick endlabeling method. In the present study, interleukin-1beta-converting enzyme (ICE) and CPP32-like protease activities in the liver of IFN-gamma transgenic mice were measured, using the synthetic substrates Ac-YVAD-MCA and Ac-DEVD-MCA. Plasma aspartate aminotransferase and alanine aminotransferase activities as well as CPP32-like activity were significantly elevated, while ICE activity was significantly reduced. The addition of the ICE inhibitor Ac-YVAD-CHO to IFN-gamma transgenic mouse liver cell cytosol had no effect on the CPP32 activity, in contrast to a CPP32 inhibitor. The present results indicate that chronic hepatitis in the IFN-gamma transgenic mouse is associated with a decrease in ICE and induction of CPP32-like activity.  相似文献   
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The reductive metabolism in vivo of a flavoring additive, trans-4-phenyl-3-buten-2-one (PBO; trans-methyl styryl ketone) was investigated in rats and dogs. In both species, the double bond-reduced product, 4-phenyl-2-butanone (PBA), was detected by HPLC as the predominant species in blood after i.v. administration of PBO. PBA detected in rat blood was identified by comparison to the authentic sample. In contrast, the carbonyl-reduced product, trans-4-phenyl-3-buten-2-ol (PBOL) was also detected as a minor metabolite of PBO in both species. The area under the curve of PBOL in rat blood was only 3% of that of PBA. PBO was mutagenic in the Ames test using Salmonella typhimurium TA 100 when S-9 mix was added, but PBA and PBOL were not. It appears that PBO is mainly metabolized to PBA in vivo in rats and dogs as a detoxification pathway.  相似文献   
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We report a case of ductal carcinoma in situ (DCIS) of the breast detected by ultrasonographic mass screening in a 51-year-old woman. In a mass screening program for breast cancer, physical examination with inspection and palpation, and ultrasonography (US) were performed. A hypoechoic mass with a slightly irregular margin was detected by US in the lateral upper quadrant of the right breast, at a distance 2 cm from the edge of the nipple. The mass was not detected by physical examinations or by mammography (MMG). The mass, which measured 0.8 x 0.5 cm and was examined by fine needle aspiration biopsy (FNAB) under US guidance, was cytologically diagnosed as class X. Modified radical mastectomy (Auchincloss method) was performed with the patient's consent. Pathological examination of the resected specimen revealed DCIS (noncomedo type) and occult multiple foci of malignancy which was considered tracking centripetally underneath the nipple. This case suggests that US and FNAB performed under US guidance are useful in the detection and diagnosis, respectively, of a breast mass. We should take multifocality into consideration, particularly with tendency tracking to the nipple, in the treatment of small breast cancers such as DCIS.  相似文献   
88.
The valvo-pump, an axial nonpulsatile blood pump implanted at the heart valve position, has been developed. The valvo-pump consists of an impeller and a motor, which are encased in a housing. An impeller with 5 vanes (22.0 mm in diameter) is used. The impeller is connected to a samarium-cobalt-rare earth magnet direct current (DC) brushless motor measuring 21.3 mm in diameter and 18.5 mm in length. Sealing is achieved by means of a ferrofluidic seal. A pump flow of 10.5 L/min was obtained at a pump differential pressure of 3.3 kPa (25 mm Hg), and a flow of 4.9 L/min was obtained at 7.0 kPa (53 mm Hg). Sealing was kept perfect against a pressure of 29.3 kPa (220 mm Hg) at 9,000 rpm.  相似文献   
89.
Key words  airway management - difficult intubation - Hallermann-Streiff syndrome  相似文献   
90.
A simultaneous manometric monitoring of the common bile duct (CBD) and the duodenum were performed 2 weeks after choledocholithotomy on 15 patients whose common bile ducts were explored without sphincteroplasty and 30 patients with sphincteroplasty. These manometric studies were carried out by open-tip catheters intubated into the CBD and duodenum through the T-tube at the operation. In patients without sphincteroplasty, no effects of the duodenal pressure on a CBD pressure profile were recognized, while a synchronized pressure profile of the CBD and the duodenum was obtained in patients with sphincteroplasty. By stimulation with morphine (Morphine sulfate; 0.17 mg/Kg iv bolus), waxing and waning of the pressured in the CBD without sphincteroplasty were observed with 20 cmH2O in maximum at about 13 minutes after injection. However, in the CBD with sphincteroplasty, scale-over increase of the pressure curve was seen immediately after duodenal contraction caused by morphine stimulation. A direct infusion of 5 ml of 0.1 N hydrochloride to the duodenum causes hyperperistalsis of the duodenum, which made a synchronized pressure profile in the CBD with sphincteroplasty but made no remarkable change in a pressure profile of the CBD without sphincteroplasty. These findings conclude that the sphincter of Oddi plays an important role as a "pressure barrier" between the CBD and the duodenum, and that with the destruction of this sphincter by sphincteroplasty, a pressure profile of the CBD becomes close to that of the duodenum. This simultaneous manometric study of the CBD and the duodenum might be one of most valuable methods for evaluation of completeness of the sphincteroplasty.  相似文献   
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