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71.
We examined the effect of methionine deficiency on iodothyronine 5’-deiodinase activity in selenium-deficient rats or selenium-sufficient
rats fed sodium selenate or selenomethionine. Forty-two weanling male Wistar rats were divided into six groups and pair fed
the respective purifiedl-amino acid-based diets for 4 wk.l-methionine concentrations in the diet were 8.0 g/kg for sufficient rats, and 2.0 g/kg for deficient rats. Selenium concentrations
in the diet were 0.5 mg/kg (as sodium selenate or selenomethionine) for selenium-sufficient rats and less than 0.005 mg/kg
for selenium-deficient rats. Type I 5’-deiodinase activities were significantly lower in liver and higher in kidney of methionine-deficient
rats than in those of methionine-sufficient rats fed either the selenium-sufficient or the selenium-deficient diets. The type
I 5’-deiodinase activity in brain was significantly lower in the methionine-deficient rats than in the methionine-sufficient
rats fed the selenium-deficient diet. Type II 5’-deiodinase activity in brain was significantly higher in the methionine-deficient
rats than in the methionine-sufficient rats fed selenium-sufficient diet as sodium selenate. Both thyroxine and 3,3’,5-triiodothyronine
concentrations in plasma were significantly higher in the methionine-deficient rats than in the methionine-sufficient rats.
It is suggested that the methionine deficiency affects the 5’-deiodinase activity and thyroid hormones level in the rats. 相似文献
72.
Chloroplast division in Nannochloris bacillaris Naumann (Chlorophyta) was examined by electron microscopy after preparation of samples by freeze-substitution. A pair of belts appeared on the surface of the outer and inner envelope membranes at the middle of the chloroplast. These belts seemed to be constructed of thin fibrils that run parallel to the longitudinal direction of the belts. The outer fibrillar belt increased in width as the constriction of the chloroplast advanced. It appears that the fibrillar belt is the division apparatus of the chloroplast. It encircles the chloroplast and finally divides the chloroplast in two as the diameter of the belt decreases. 相似文献
73.
74.
75.
Q. Wang C.K. Noguchi M. Kuninobu Y. Hara K. Kakimoto H.I. Ogawa Y. Kato 《Biotechnology Techniques》1997,11(2):105-108
Continuous anaerobic digestion of waste activated sludge pretreated at low temperatures below 100°C increased methane generation by 30%. pH values of the digestion mixture increased, approximately from 0.3 to 0.55 by pretreatment, although its volatile fatty acids concentration was greater than the control. An abrupt increase in propionate : acetate ratio in digestion stage (e.g. from less than 1:1 to over 3.5 :1), provided a reliable indicator for impending failure.This revised version was published online in October 2005 with corrections to the Cover Date. 相似文献
76.
Physical effects of negative air ions in a wet sauna 总被引:10,自引:0,他引:10
I. Watanabe Hiroshi Noro Yoshinori Ohtsuka Yukio Mano Yuko Agishi 《International journal of biometeorology》1997,40(2):107-112
The physical effects of negative air ions on humans were determined in an experimental sauna room equipped with an ionizer.
Thirteen healthy persons took a wet sauna bath (dry bulb temperature 42° C, relative humidity 100%, 10 min exposure) with
or without negative air ions. The subjects were not told when they were being exposed to negative air ions. There were no
differences in the moods of these persons or changes in their blood pressures between the two saunas. The surface temperatures
of the foreheads, hands, and legs in the sauna with negative ions were significantly higher than those in the sauna without
ions. The pulse rates and sweat produced in the sauna with ions were singificantly higher than those in the sauna without
ions. The results suggest that negative ions may amplify the effects on humans of the sauna.
Received: 31 March 1995 / Revised: 25 July 1995 / Accepted: 26 July 1996 相似文献
77.
Shunji Tomatsu Seiji Fukuda Alan Cooper James E. Wraith Atsushi Uchiyama Toshinori Hori Yoshinori Nakashima Naoto Yamada Kazuko Sukegawa Naomi Kondo Yasuyuki Suzuki Nobuyuki Shimozawa Tadao Orii 《Human genetics》1995,95(4):376-381
Ninety-six alleles (36 alleles of Japanese and 60 of Caucasian origin) from forty-eight patients with mucopolysaccharidosis IVA were investigated for structural gene alterations using Southern blot analysis. All patients had a previously demonstrated deficiency of N-acetylgalactosamine-6-sulfate-sulfatase and exhibited a wide spectrum of clinical severity. Initially, using the fulllength cDNA as a probe, five of 36 chromosomes from the Japanese patients revealed similar rearrangements with respect to DNA digested with BamHI, SacI, and XhoI. Subsequent analysis using seven genomic fragments, covering the entire gene, enhanced the detection of aberrant fragments produced by the above restriction enzymes. Conversely, the 60 chromosomes of Caucasian origin revealed no evidence of large structural rearrangements when analyzed by these methods. There was a statistically significant difference between the two populations (P < 0.01). A severely affected Japanese patient showed structural rearrangements on both chromosomes by means of BamHI blots. An 8.0-kb fragment and a highly polymorphic 7.0-kb to 11.0-kb fragment present in normal individuals disappeared and two aberrant fragments of 11.5 kb and 12.0 kb were observed. Three other Japanese patients also showed these two aberrant fragments, in addition to the normal fragment pattern, and were thus heterozygous for this rearrangement. Interpretation of Southern blots was difficult because of the complexity of polymorphic bands resulting from variable number of tandem repeat elements. However, by utilizing these aberrant fragments or polymorphic bands, carrier detection was effective, even in families with poorly characterized mutations. Hybridization with probe MG-A (5end genomic probe in intron 1) showed a 8.4-kb fragment in BamHI blots of one Japanese and one Caucasian patient; XhoI, SacI, and EcoRI blots were normal. Since this BamHI alteration was also observed in one normal control, it appears to be a rare nonpathological polymorphism. 相似文献
78.
Using a laser confocal microscope, chromatin arrangements in intact interphase nuclei were investigated in four plant species.
Chromosomes in these plants have specific segments that can be stained with the fluorescent dye chromomycin A3 (CMA). We stained centromeres inHordeum vulgare, sub-telomeric regions inSecale cereale, satellites inChrysanthemum multicore, and the satellites and the short arms of chromosomes with satellites inHemerocallis middendorfii. The following points were shown: (1) In mitotic interphase nuclei, the centromere and the telomeres of both arms touched
the nuclear membrane and had evident polarity. Some CMA-bodies in sub-telomeric regions do not contact the nuclear membrane.
(2) Differentiated nuclei had a non-random construction. Polarity of chromosomes is maintained, however, the chromosomes are
far apart from the nuclear membrane. (3) Associations in sub-telomeric regions in the interphase nuclei ofSecale cereale were probably due to the association of heterochromatic regions with identical repeated sequences rather than telomere associlations.
(4) In interphase nuclei ofChrysanthemum multicore, satellites fused during interphase. 相似文献
79.
Cell-free synthesis of ornithine decarboxylase. Changes in mRNA activity in the liver of thioacetamide-treated rats 总被引:1,自引:0,他引:1
T Kameji K Fujita T Noguchi M Takiguchi M Mori M Tatibana S Hayashi 《European journal of biochemistry》1984,144(1):35-39
Ornithine decarboxylase (ODC)mRNA associated with free polysomes of rat liver was translated in a reticulocyte lysate cell-free system. Newly synthesized ODC protein was identified by specific immunoprecipitation, molecular size as determined by polyacrylamide gel electrophoresis with sodium dodecyl sulfate, and competition by excess unlabeled ODC in the immunoprecipitation. A single injection of thioacetamide was found to cause several fold increases in both immunotitratable ODC protein and polysomal ODC-mRNA activity, while it provoked a much larger increase in ODC activity in rat liver. The results indicate that the induction of hepatic ODC activity by thioacetamide treatment is due not only to an increase in the activity of polysomal ODC-mRNA but also to a translational and/or posttranslational control. 相似文献
80.
The Δ9-desaturase system in liver microsome from rats treated chronically with ethanol was studied. Stearoyl-CoA desaturase activity decreased by 80% and palmitoyl-CoA desaturase activity was not detectable in microsomes from ethanol-fed rats, while activities of electron transport components such as NADH-cytochrome c and NADH-ferricyanide reductases remained unchanged. However, chronic ethanol administration resulted in an adaptive induction of the activity of NADPH-cytochrome c reductase and the contents of cytochrome b5 and P-450. The activity of the terminal component (cyanide-sensitive factor; CSF) of the desaturase system was greatly depressed by ethanol treatment. The NADH/NAD ratio in microsomes of ethanol-fed rats increased over 2-fold. These results suggest that, during chronic ethanol ingestion, decreased activities of Δ9-desaturases are due mainly to a decreased content of the terminal component of the desaturase system. 相似文献