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1.
2.
Masatoshi Kataoka Keizoh Kawamura Tamotsu Kondoh Yoichi Wakano Hiroshi Ishida 《FEMS microbiology letters》1993,107(1):111-114
Abstract A factor showing inhibitory activity against human gingival fibrolasts was extracted from the cytosol fraction of Actinobacillus actinomycetemcomitans Y4. The activity markedly inhibited the proliferation of human gingival fibrolasts, but had no effect on cell viability or gross morphology. No such activity was found in cytosol fractions from either Porphyromonas gingivalis 381 or Escherichia coli HB101. The extract from A. actinomycetemcomitans Y4 was then purified by anion-exchange chromatography, hydroxyapatite chromatography and gel-filtration chromatography to give a single band on SDS-PAGE with an apparent molecular mass of 65 kDa. The purification ratio was 183-fold with a recovery rate of 5% compared with the crude extract (starting material) when the activity was assessed by direct cell counts. 相似文献
3.
C Shigemasa K Abe S Taniguchi Y Mitani Y Ueta K Urabe T Adachi T Tanaka A Yoshida H Mashiba 《Endocrinologia japonica》1987,34(6):821-829
Serum total thyroxine (T4), total triiodothyronine (T3), T4-binding globulin (TBG), free T4(FT4) and free T3(FT3) concentrations and the T3-uptake(T3-U) value were estimated in 11 patients with subacute thyroiditis, and compared with the same parameters in 11 patients with Graves' disease, whose serum T4 concentrations were similar to the former group. Seven patients with subacute thyroiditis, who were treated with dicrofenac sodium alone, were investigated as to the sequential changes in serum parameters during their clinical courses. The mean serum T3-U value and FT4, T3 and FT3 concentrations in patients with subacute thyroiditis were increased, but all were significantly lower than those in patients with Graves' disease (p less than 0.01, p less than 0.001, p less than 0.001 and p less than 0.001, respectively). Three patients with subacute thyroiditis, who showed shorter duration of symptoms than 10 days, had serum TBG excess. Thus the mean (+/- SD) serum TBG concentration (26.5 +/- 8.4 micrograms/ml) was significantly higher than that (18.3 +/- 2.9 micrograms/ml) in patients with Graves' disease (p less than 0.02). The ratios of serum T3 to T4 and FT3 to FT4 in patients with subacute thyroiditis were also significantly lower than those in patients with Graves' disease (p less than 0.001 and p less than 0.001, respectively). The serum FT4 in 7 patients treated with dicrofenac sodium alone decreased to the normal range after 3 to 8 weeks from the onset of the illness. In 3 patients with TBG excess and one patient (TBG; 29.0 micrograms/ml), serum TBG declined in consequence of the serum FT4 normalization.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
4.
M Mita N Ueta 《Comparative biochemistry and physiology. B, Comparative biochemistry》1989,92(2):319-322
1. An analysis was made of lipids extracted from the spermatozoa of the sea urchins, Hemicentrotus pulcherrimus and Anthocidaris crassispina. 2. Nearly all the lipids from both species consisted of phospholipids (about 80%) and cholesterol (about 14%). Triglyceride and cholesterol ester were present in trace amounts. 3. The fatty acid composition of each phospholipid was determined by gas-liquid chromatography. In both species, the fatty acid consisting of phosphatidylethanolamine was of the unsaturated type for the most part, while cardiolipin was comprised to a considerable degree of saturated fatty acids. In phosphatidylcholine and phosphatidylserine from H. pulcherrimus sperm, unsaturated fatty acid content was somewhat higher than that in phospholipids from A. crassispina sperm. 相似文献
5.
Koji Sode Nobuaki Hori Yoichi Mikami Isao Karube 《Biocatalysis and Biotransformation》1988,2(1):51-57
Asymmetric reduction of 2,6,6,-trimethyl-2-cyclohexene-l,4-dione (4-oxoisophrone) to (6R)-2,2,6-trimethyl-1,4-cyclohexane-dione((3R)-dihydro-4-oxoisophorone) was catalysed by immobilized thermophilic bacteria, Thermomonospora curvata JTS 321. Because of leakage of entrapped cells from gel beads during reactions using culture medium, we optimized the medium to allow the microbial conversion under conditions of controlled cell growth. Of the media screened, liver infusion medium was found to be the most suitable and microbial conversion was achieved without cell leakage from the immobilized gels. Immobilized T. curvata cells were repeatedly used for the asymmetric reduction of 4-oxoisophorone, more than 15 times, with an extent of conversion of 50%. 相似文献
6.
Camilynn I. Brannan Debra J. Gilbert Jeffrey D. Ceci Yoichi Matsuda Verne M. Chapman John A. Mercer Harvey Eisen Laura A. Johnston Neal G. Copeland Nancy A. Jenkins 《Genomics》1992,13(4):1075-1081
We have used an interspecific backcross between C57BL/6J and Mus spretus to derive a molecular genetic linkage map of chromosome 15 that includes 25 molecular markers and spans 93% of the estimated length of chromosome 15. Using a second interspecific backcross that was analyzed with a centromere-specific marker, we were also able to position our map with respect to the chromosome 15 centromere. This map provides molecular access to many discrete regions on chromosome 15, thus providing a framework for establishing relationships between cloned DNA markers and known mouse mutations and for identifying homologous genes in mice and humans that may be involved in disease. 相似文献
7.
Monica J. Justice Bebra J. Gilbert Kenneth W. Kinzler Bert Vogelstein Authur M. Buchberg Jeffrey D. Ceci Yoichi Matsuda Verne M. Chapman Christos Patriotis Antonios Makris Philip N. Tsichlis Nancy A. Jenkins Neal G. Copeland 《Genomics》1992,13(4):1281-1288
An interspecific backcross between C57BL/6J and Mus spretus was used to generate a molecular genetic linkage map of mouse chromosome 18 that includes 23 molecular markers and spans approximately 86% of the estimated length of the chromosome. The Apc, Camk2a, D18Fcr1, D18Fcr2, D18Leh1, D18Leh2, Dcc, Emb-rs3, Fgfa, Fim-2/Csfmr, Gnal, Grl-1, Grp, Hk-1rs1, Ii, Kns, Lmnb, Mbp, Mcc, Mtv-38, Palb, Pdgfrb, and Tpl-2 genes were mapped relative to each other in one interspecific backcross. A second interspecific backcross and a centromere-specific DNA satellite probe were used to determine the distance of the most proximal chromosome 18 marker to the centromere. The interspecific map extends the known regions of linkage homology between mouse chromosome 18 and human chromosomes 5 and 18 and identifies a new homology segment with human chromosome 10p. It also provides molecular access to many regions of mouse chromosome 18 for the first time. 相似文献
8.
Energy metabolism of sea urchin spermatozoa, with phosphatidylcholine as the preferred substrate 总被引:1,自引:0,他引:1
Phosphatidylcholine content in the spermatozoa of the sea urchin, Hemicentrotus pulcherrimus, decreased rapidly during incubation with sea water. Sea urchin sperm contained approx. 85% phospholipid in total lipid. Phosphatidylcholine (PC) was the principal lipid. Other phospholipids, however, remained at constant levels during incubation. Although the free fatty acid content gradually increased following dilution of dry sperm in sea water, the amounts of triacylglycerol and cholesterol ester were extremely low. Analysis by gas-liquid chromatography indicated most of fatty acid moieties in PC to be polyenoic. PC composed in part of unsaturated fatty acids was consumed to a greater extent during incubation than that consisting of saturated fatty acids. Furthermore, 1-palmitoyl-2-[1-14C]linoleoylphosphatidylcholine was transformed to 14C-labelled free fatty acid in a subcellular system. Thus, possibly, phospholipase A2 is present in sea urchin sperm. Also, [1-14C]oleic acid was immediately oxidized to 14CO2 by sperm. It is thus concluded that sea urchin sperm use phosphatidylcholine as a substrate for energy metabolism. 相似文献
9.
Ken-ichi Yamamoto Osamu Hirano Yoichi Hara Hiroshi Yoshikawa 《Ichthyological Research》1987,33(4):399-404
A cyprinid fish,Pseudogobio esocinus showed gradual bradycardia at oxygen saturation (%) of less than 29.7±4.6 (1.89±0.29 ml/l of oxygen concentration), surfacing at 14.7±1.3 (0.94±0.09ml/l), drastic decrease of oxygen consumption at less than 14.2±0.8 (0.91 ±0.06ml/l) and asphyxia at 9.7±1.4 (0.62±0.09ml/l). The fish avoided water having low oxygen saturation of less than 54.0± 5.4 (3.38±0.30ml/l), and markedly at less than 26.2±3.4 (1.62±0.16 ml/l). 相似文献
10.