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81.
We investigated intestinal ethanol absorption in rats pretreated with saline, cyanamide, 4-methylpyrazole and cyanamide + 4-methylpyrazole. The value of the absorption rate constant in the cyanamide-pretreated group with high acetaldehyde levels was the lowest among the four groups, but there were no significant differences among the remaining groups. We found that high acetaldehyde concentration itself clearly reduces intestinal ethanol absorption.  相似文献   
82.
We experienced that therapeutic embolization of a large cerebral arteriovenous malformation (AVM) led to venous outflow obstruction resulting in intracranial hypertension in a patient who had undergone external decompression. To evaluate hemodynamic changes after embolization, we monitored the cerebrospinal fluid pressure in the next four patients who underwent endovascular treatment. The embolization of a medium AVM resulted in a slight increase in the cerebrospinal fluid pressure. In two medium AVMs, embolization produced slight decreases in the cerebrospinal fluid pressure. In a small AVM, we did not observe any changes in the cerebrospinal fluid pressure during the endovascular treatment. We discuss the mechanism of changes in the intracranial pressure after embolization and conclude that monitoring of the cerebrospinal fluid pressure immediately yields useful information for hemodynamic changes during endovascular treatment.  相似文献   
83.
While an ECL-CMOS SRAM can achieve both ultra high speed and high density, it consumes a lot of power and cannot be applied to low power supply voltage applications. This paper describes an NTL (Non Threshold Logic)-CMOS SRAM macro that consists of a PMOS access transistor CMOS memory cell, an NTL decoder with an on-chip voltage generator, and an automatic bit line signal voltage swing controller. A 32 Kb SRAM macro, which achieves a 1 ns access time at 2.5 V power supply and consumes a mere 1 W, has been developed on a 0.4 μm BiCMOS technology  相似文献   
84.
85.
Eight patients with nasal lymphoma in whom fresh-frozen tissues were available were studied to elucidate the nature of the lymphoma cells. Two cases were diagnosed as diffuse, large cell lymphoma, and the remaining six cases as diffuse, mixed cell types. Immunohistochemical studies revealed that all of the cases were positive for perforin, which is a specific marker for cytotoxic T or natural killer (NK) cells. As all of the cases were CD8 negative, the perforin-positive finding further confirmed the concept that nasal lymphoma is a distinct neoplastic entity derived from NK or NK-related cells. Light microscopic immunohistochemical studies revealed that these nasal lymphoma cases could be classified into Leu19(CD56)+Leu4(CD3)+ (two cases) and Leu19(CD56)+Leu4(CD3)- (six cases) types according to the phenotypes of the proliferating cells. However, simultaneous staining for perforin and Leu4 (CD3) using immunoelectron microscopy on the Leu19+Leu4+ cases showed that the perforin-positive cells were different from the Leu4-positive cells. This finding suggests that the Leu4-positive cells are not neoplastic NK cells but reactive T cells. Six cases were positive for EBER-1 by in situ hybridization analysis. This finding reconfirms the previous studies that Epstein-Barr virus plays a significant role in the pathogenesis of nasal lymphoma.  相似文献   
86.
Satoyoshi syndrome consists of painful intermittent muscle spasms, alopecia and diarrhea. The age of onset is commonly less than 20 years of age. Adult onset of this syndrome is rare. We report a 65-year-old Japanese woman with Satoyoshi's syndrome of adult onset. Satoyoshi's syndrome of adult onset shows no skeletal abnormalities, in comparison with the classical pediatric cases. The clinical features in our patient revealed the benign and long-term course of muscle spasm and alopecia. This progression differed markedly from the other patients of adult onset. Thus, the severity of Satoyoshi's syndrome is variable in adult onset cases, and this diagnosis should be considered in adults with various and unexplained muscle spasms.  相似文献   
87.
In an attempt to define better surgical strategies for patients with hepatocellular carcinoma (HCC), we conducted a retrospective analysis of 452 patients who underwent hepatic resection at our institute during a period of 15 years. The patients were divided into two groups: group A, comprising 188 patients who underwent hepatic resection before 1988, and group B, comprising 264 patients after 1989. These groups were compared clinicopathologically. The percentage of patients with Child's A disease but without cirrhosis, in group A was lower. The diameter of the resected tumor was larger in group A, and major hepatic resections and curative operations were more frequently performed in group A. In group B, there was less blood loss, the specimen weighed less, and the hospital mortality was lower. Although the tumor-free survival rates were similar between the two groups, the survival rate in group B was significantly better. While even minor hepatic resection accompanied by a lower rate of surgical margin-free surgery has contributed to making hepatic resection safer, it has not improved the tumor-free survival rate. Conversely, recent advances in imaging modalities used during follow-up for the early detection of recurrence and for planning multimodality treatment have contributed to increasing the survival rate.  相似文献   
88.
We retrospectively examined the influence of left ventricular wall thickening on myocardial injury in aortic valve replacement. Thirty-five patients who underwent aortic valve replacement in our hospital between January 1995 and July 1997 were studied. We divided these patients into 3 groups: group N (left ventricular thickness (LVT) < or = 10 mm), group H (10 < LVT < or = 15 mm), and group S (LVT > 15 mm). All patients of group S had aortic stenosis. CK and CK-MB were significantly higher and the cardiac index was significantly lower in group S than in the other groups. Intra-aortic balloon pumping was required for 50% of patients in group S, and a total dose of catecholamine above 10 micrograms/kg/min was also required for 50% of patients in this group. In the other groups, these percentages were significantly lower. Myocardial protection and postoperative care were difficult for patients with severe left ventricular hypertrophy with LVT over 15 mm in this study. Left ventricular wall thickness was a more important factor in determining difficulty with intraoperative myocardial protection than was left ventricular mass.  相似文献   
89.
As the most abundant cell type in the central nervous system, astrocytes are positioned to nurture and sustain neurons, especially in response to cellular stresses, which occur in ischemic cerebrovascular disease. In a previous study (Hori, O., Matsumoto, M., Kuwabara, K., Maeda, M., Ueda, H., Ohtsuki, T., Kinoshita, T., Ogawa, S., Kamada, T., and Stern, D. (1996) J. Neurochem., in press), we identified five polypeptide bands on SDS-polyacrylamide gel electrophoresis, corresponding to molecular masses of about 28, 33, 78, 94, and 150 kDa, whose expression was induced/enhanced in astrocytes exposed to hypoxia or hypoxia followed by replacement into the ambient atmosphere (reoxygenation). In the current study, the approximately 150-kDa polypeptide has been characterized. Chromatography of lysates from cultured rat astrocytes on fast protein liquid chromatography Mono Q followed by preparative SDS-polyacrylamide gel electrophoresis led to isolation of a approximately 150-kDa band only observed in hypoxic cells and which had a unique N-terminal sequence of 15 amino acids. Antisera raised to either the purified approximately 150-kDa band in polyacrylamide gels or to a synthetic peptide comprising the N-terminal sequence detected the same polypeptide in extracts of cultured rat astrocytes exposed to hypoxia; expression was not observed in normoxia but was induced by hypoxia within 24 h, augmented further during early reoxygenation, and thereafter decreased to the base line by 24 h in normoxia. ORP150 expression in hypoxic astrocytes resulted from de novo protein synthesis, as shown by inhibition in the presence of cycloheximide. In contrast to hypoxia-mediated induction of the approximately 150-kDa polypeptide, neither heat shock nor a range of other stimuli, including hydrogen peroxide, cobalt chloride, 2-deoxyglucose, or tunicamycin, led to its expression, suggesting selectivity for production of ORP150 in response to oxygen deprivation, i.e. it was an oxygen-regulated protein (ORP150). Northern and nuclear run-off analysis confirmed the apparent selectivity for ORP150 mRNA induction in hypoxia. Subcellular localization studies showed ORP150 to be present intracellularly within endoplasmic reticulum and only in hypoxic astrocytes, not cultured microglia, endothelial cells, or neurons subject to hypoxia. Consistent with these in vitro results, induction of cerebral ischemia in mice resulted in expression of ORP150 (the latter was not observed in normoxic brain). These data suggest that astroglia respond to oxygen deprivation by redirection of protein synthesis with the appearance of a novel stress protein, ORP150. This polypeptide, selectively expressed by astrocytes, may contribute to their adaptive response to ischemic stress, thereby ultimately contributing to enhanced survival of neurons.  相似文献   
90.
The pyruvate dehydrogenase complex (PDC) plays a key role in the anaerobic mitochondrial metabolism of the parasitic nematode Ascaris suum. A cDNA coding for an A. suum pyruvate dehydrogenase kinase (APDK) has been cloned and sequenced from poly(A)+ RNA isolated from adult A. suum muscle.2 APDK exhibited significant sequence identity to mammalian PDKs. Nucleotide sequence analysis of the APDK cDNA revealed a 22-nucleotide spliced leader, characteristic of many nematode mRNAs, a 5'-UTR of 6 nucleotides, an open reading frame of 1197 nucleotides, and a 3'-UTR of 101 nucleotides that included a putative polyadenylation signal. The open reading frame predicted a protein of 399 amino acids with a molecular weight of 45,402 that included a putative 18-aminoacid leader peptide. Recombinant APDK (rAPDK) was functionally expressed in Escherichia coli with a his tag at its N-terminus and purified to apparent homogeneity on Ni-NTA-agarose. Recombinant APDK was a dimer and was not autophosphorylated and its activity was stimulated in the presence of APDK-deficient adult A. suum muscle PDC presumably by the binding of APDK to the dihydrolipoyl transacetylase (E2) core of the complex. After binding to the core, rAPDK activity was stimulated by elevated NADH/NAD+ and acetyl CoA/CoA ratios within the same ranges as observed for the native APDK. Immunoblotting suggested that native APDK focused as a series of 43-kDa spots (pI 6.1-6.8) on two-dimensional gels of the purified adult A. suum muscle PDC.  相似文献   
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