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991.
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Horseradish peroxidase (HRP, 10 mg/100 g body weight) was intravenously injected into rats in order to investigate the nature of the compartments involved in the transcellular transport of the protein through hepatocytes into bile. Double cytochemistry for HRP and the marker enzymes for cytoplasmic organelles was used. HRP was shown to be taken up by hepatocytes via vesicles at the sinusoidal surface, some of which were positive for 5'-nucleotidase activity. HRP was then found in the smooth-surfaced vesicles and tubules which were negative in 5'-nucleotidase, glucose 6-phosphatase, thiamine pyrophosphatase and acid phosphatase activity, suggesting that the tubular structures are neither the endoplasmic reticulum, the Golgi apparatus nor lysosomes. Biochemical studies revealed that the lead procedures used for the double cytochemistry did not inhibit the peroxidatic activity of HRP, and conversely that HRP did not interfere with the marker enzyme activity. Such cytochemical observations seemed to be supported by the observation that administration of monensin (3.5 mg/100 g) and chloroquine (5 mg/100 g), which markedly altered the structure of the Golgi apparatus and lysosomes, respectively, slightly altered the biliary excretion of HRP but not to a significant extent.  相似文献   
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In mouse spleen cell cultures, TH69, a live Streptococcus faecalis (ATCC 31663) preparation, at a concentration of 20 micrograms/ml induced immune interferon (IFN gamma) with molecular weight ranging from 20,000 to 40,000 daltons together with a small amount of IFN alpha/beta. By using nonsensitized mouse spleen cells, the fact that both T-cells and macrophages are required for this IFN production was established. When these spleen cells were obtained from mice sensitized 12 days earlier with 4 mg of TH69, twice as much IFN was produced than in cells obtained from nonsensitized mice. This increase was explained by the presence of both sensitized macrophages and T-cells in a reconstitution experiment.  相似文献   
996.
Surfactant rich lipid (lipid) was extracted from cell free 10,000 x g pellets of amniotic fluid. White blood cells (WBC) were isolated from human donors. 36 x 10(7) WBC and 5 g rabbit lung were incubated with pretreated lipid or dipalmitoyl lecithin (lecithin). Leukotrienes (LTs) were identified by high performance liquid chromatography (HPLC) and bioassay, and quantified by radioimmunoassay. Peaks of LTC4 and LTD4 on HPLC and guinea-pig ileum contraction could be identified in lipid and lecithin groups, but not in the control group. LTC4 production by lipid and lecithin groups was significantly higher than that by the control group. An involvement of amniotic fluid surfactant in leukotriene production is suggested.  相似文献   
997.
The components of fractions obtained by dialyzing and differential centrifuging the “Ghost” of Bacillus megaterium were analyzed in detail. The compositions of amino acids in the main fractions (Fraction 2 and 3) of the “Ghosts”, were estimated. Fraction 2 was rich in non-polar amino acids, while Fraction 3 was scanty of them. Most of the fatty acids in Fraction 2 were 12-methyl tetradecanoic acid, while in Fraction 3 many kinds of fatty acid were detected.

As for the localization of enzymes, the three enzymes, glucose oxidase, succinic dehydrogenase and reduced nicotinamide-adenine dinucleotide oxidase, which were present in the original “Ghosts”, were mostly observed in Fraction 2, and a very little amount of them was found in the other fractions. Further, Fraction 2 could be dissolved in formic acid and dialysis of the solution brought about reaggregation to form membrane-like structure in the presence of Ca or Mg ion.  相似文献   
998.
Early detection of dementia is crucial because it is the time when intervention is most effective. Therefore, a simple and short test is necessary for primary mass screening in community-based medical facilities. We developed the Cognitive Assessment for Dementia, iPad version (CADi) which consists of 10 simple questions and is self-administered. In this paper we present a revised version which improves the detection of dementia. Two questions of the CADi were replaced in the latest version (CADi2). We examined the validity and reliability of the CADi2 in 27 Alzheimer’s disease patients and age-matched healthy controls. The Alzheimer’s disease patients had lower CADi2 scores and longer total response times to questions compared to the controls. The CADi2 had high sensitivity (0.85−0.96) and specificity (0.81−0.93), and showed significant correlations with existing standard neuropsychological tests. Cronbach’s alpha analysis revealed moderate consistency of the CADi2. These results support the utility of the CADi2 for primary screening for dementia.  相似文献   
999.
3-Ketothiolase deficiency (3KTD) is the result of a deficiency in mitochondrial acetoacetyl-CoA thiolase (T2). The molecular basis of 3KTD was analyzed in a patient (GK10) and his family at the protein, cDNA and gene levels. Protein analyses showed that GK10's T2 protein was undetectable in fibroblasts even with the pulse-protein labeling method and that his parents were carriers of 3KTD. Complementary DNA analyses with PCR showed that T2 cDNA in the patient lacked the normal exon 11 sequence and that his parents were obligatory carriers of the DNA sequence which canceled exon 11. When the PCR-amplified genomic fragments around exon 11 were sequenced, an AG to AC mutation at the 3' splice site of intron 10 was detected. This mutation is presumed to be responsible for exon 11 skipping.  相似文献   
1000.
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