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991.
992.
Takaki Fukuizumi Hiromasa Inoue Yuichi Anzai Toshiyuki Tsujisawa Choji Uchiyama 《Microbiology and immunology》1995,39(5):351-359
We have shown that the palatine tonsil effectively incorporates exogenous foreign substances instilled at its surface. It is not clear whether antigen-specific IgA can be induced by the instillation. Sheep red blood cells (SRBC) were instilled at the palatine tonsil every three days as the antigen, and the agglutination titer of specific IgA in saliva was examined. Nasal or intragastric administration, which have been shown to induce specific antibody in saliva, were done as control experiments. Anti-SRBC antibody in saliva from the tonsillar instillation group was detected in the second week, and the agglutination titer reached a maximum in the 6th week after the instillation. The maximum titers in the tonsillar instillation group and nasal administration group were 16 (P<0.01, n=7) and 4 times (P<0.01, n = 7) higher, respectively, than that in the intragastric administration group. In the tonsillar instillation group, the number of specific antibody-producing cells per 105 lymphocytes was the highest in the parotid glands compared with the lymphoid tissues such as the retropharyngeal lymph nodes, nasal mucosa, mesenteric lymph nodes, Peyer's patches, cervical lymph nodes, palatine tonsil and spleen. In the nasal administration group, the number of lymphocytes was the highest in the nasal mucosa. The results indicate that tonsillar instillation was more effective than nasal administration in inducing specific IgA in saliva. 相似文献
993.
Yasutomo Takeuchi Yumi Omigawa Masaru Ogasawara Koichi Yoneyama Makoto Konnai A. Douglas Worsham 《Plant Growth Regulation》1995,16(2):153-160
Brassinolide [2, 3, 22R,23R-tetrahydroxy-24S-methyl-B-homo-7-oxa-5--cholestan-6-one] and its related compounds, brassinosteroids, applied at the early stages of conditioning shortened the conditioning period required before clover broomrape seeds would germinate after exposure to germination stimulants, such as dl-strigol and natural stimulants from red clover (Trifolium pratense L.) root exudate. Brassinosteroids applied after conditioning increased the rate of the seed germination induced by these stimulants. The inhibitory effect of light on seed germination when it was induced by dl-strigol could be overcome by brassinosteroids. Brassinosteroids also eliminated the inhibitory effects of light and dl-strigol applied at the early stages of conditioning. GA3 was also effective in causing seed conditioning and increased the rate of the germination induced by these stimulants. There was a relationship between brassinosteroids and GA3 in many of the experiments conducted. These findings may have practical implications in increasing the effectiveness of applying germination stimulants in the field to soils for suicidal germination of broomrape seeds. 相似文献
994.
995.
Thiobacillus thiooxidans cells became more hydrophobic but less adhesive to elemental sulfur in the presence of increasing potassium phosphate concentrations. At a fixed concentration of potassium phosphate, however, there was a peak of both cell hydrophobicity and adhesion to sulfur at around pH 5. Oxidation of sulfur by the cells was affected in a complex manner by the phosphate concentration and pH, although it was inhibited by a high concentration of potassium phosphate. 相似文献
996.
Spontaneous establishment of an Epstein-Barr virus-infected fibroblast line from the synovial tissue of a rheumatoid arthritis patient. 总被引:3,自引:0,他引:3 下载免费PDF全文
J Koide K Takada M Sugiura H Sekine T Ito K Saito S Mori T Takeuchi S Uchida T Abe 《Journal of virology》1997,71(3):2478-2481
An Epstein-Barr virus (EBV)-infected fibroblast line, designated DSEK, was spontaneously established from synovial tissue of a patient with rheumatoid arthritis (RA). DSEK cells expressed EBV nuclear antigens EBNA-1 and EBNA-2 and latent membrane protein LMP-1. Cell surface markers of DSEK cells were similar to those of EBV-negative fibroblast clones derived from synoviocytes and were negative for lymphocyte and macrophage markers. DSEK cells expressed CD44, CD58, and HLA-DR antigens and spontaneously produced interleukin-10 basic fibroblast growth factor and transforming growth factor beta1. These results indicate that rheumatoid synoviocytes can be a target for EBV infection and suggest that EBV may play a role in the pathogenesis of RA. 相似文献
997.
Wenresti G. Gallardo Atsushi Hagiwara Yuichi Tomita Kiyoshi Soyano Terry W. Snell 《Hydrobiologia》1997,358(1-3):113-120
Eight vertebrate and invertebrate hormones were screened for theireffect on population growth, mictic female production, and body size of themarine rotifer Brachionus plicatilis. Growth hormone (GH) or human chorionicgonadotropin (HCG) at 0.0025–25 I.U. ml–1 andestradiol-17 (E2), triiodothyronine (T_3),20-hydroxyecdysone (20-HE), 5-hydroxytryptamine (5-HT), gamma-aminobutyricacid (GABA) or juvenile hormone (JH) at 0.05–50 mg l–1were added to 5-ml of Nannochloropsis oculata suspension (7×106 cells ml–1). From an initial densityof 1 individual ml–1, rotifers were cultured with hormones for48 hours in 22 ppt seawater at 25 °C, in darkness.Rotifers were counted and classified into female types and transferred to anew algal food suspension without hormone every other day until day 8 whenbody size was measured. Population growth was significantly higher intreatments exposed to GABA (50 mg l–1), GH (0.0025 and 0.025I.U. ml–1), HCG (0.25 and 2.5 I.U. ml–1), and5-HT (5 mg l–1). E2 caused a decrease inpopulation growth, whereas JH, 20HE, and T3 had no effect.Mictic female production was significantly higher at 0.05 and 0.5 mgl–1 JH and 0.05 and 5 mg l–1 5HT. GH (0.0025 and0.025 I.U. ml–1), E2 (50 mg l–1),GABA (0.5, 5 and 50 mg l–1), and 20-HE (0.05 mgl–1) treatments had significantly higher mictic femaleproduction only on day 8, 6, 4, and 6, respectively. T3 andhCG had no effect on mictic female production. Lorica length increased by9.6% and 4.4% in rotifers treated with JH (0.05 mgl–1) and GABA (5 mg l–1), respectively. Correspondingly, lorica width increased by 8.9% and 2.6% inthese treatments. In comparison, 20-HE-, T3-, and HCG-treatedrotifers were smaller (3.9–8.2%) and GH, 5-HT andE2 had no effect on rotifer body size. 相似文献
998.
A 570-kb DNA Sequence of the Escherichia coli K-12 Genome Corresponding to the 28.0-40.1 min Region on the Linkage Map 总被引:1,自引:0,他引:1
Aiba Hiroji; Baba Tomoya; Hayashi Kouji; Inada Toshifumi; Isono Katumi; Itoh Takeshi; Kasai Hiroaki; Kashimoto Kaoru; Kimura Shigenobu; Kitakawa Madoka; Kitagawa Masanari; Makino Kozo; Miki Takeyoshi; Mizobuchi Kiyoshi; Mori Hirotada; Mori Tomoko; Motomura Kouji; Nakade Shinsuke; Nakamura Yoshikazu; Nashimoto Hiroko; Nishio Yoshitaka; Oshima Taku; Saito Noriko; Sampei Gen-ichi; Seki Yasushi; Sivasundaram Suharnan; Tagami Hideaki; Takeda Jun-ichi; Takemoto Keiko; Takeuchi Yasushi; Wada Chieko; Yamamoto Yoshihiro; Horiuchi Takashi 《DNA research》1996,3(6):363-377
The 569,750 base pair sequence corresponding to the 28.040.1min region on the genetic map of Escherichia coli K-12 (W3110)was determined. This region includes the replication terminusregion and contained at least 549 potential open reading frames.Among them, 160 (29%) were previously reported, 174 (32%) werehomologous to other known genes, 102 (18%) were identical orsimilar to hypothetical genes registered in databases, and theremaining 113 (21%) did not show a significant similarity toany other gene. Of interest was the finding of a large numberof genes and gene clusters in andnear the replication terminationregion which had been thought to be genetically silent. Thoseincludeda cluster of genes for fatty acid ß-oxidation,the third copy of the pot (spermidine/putrescine transport system)gene cluster, the second dpp (dipeptide transport system) operon,the second dsm (anaerobic dimethyl sulfoxide reductase) operon,a cluster of fim (fimbrial) genes anda DNA helicase-like genewith a high molecular weight. In addition, we found the dnaC-and dnaT-like genes in the cryptic prophage, Rac, anda numberof genes originated probably from plasmids. 相似文献
999.
Takarada Yudai; Iwamoto Hiroyuki; Sugi Haruo; Hirano Yuichi; Ishii Naokata 《Journal of applied physiology》1997,83(5):1741-1748
Takarada, Yudai, Hiroyuki Iwamoto, Haruo Sugi, YuichiHirano, and Naokata Ishii. Stretch-induced enhancement ofmechanical work production in frog single fibers and human muscle.J. Appl. Physiol. 83(5):1741-1748, 1997.The relations between the velocity of prestretchand the mechanical energy liberated during the subsequent isovelocityrelease were studied in contractions of frog single fibers and humanmuscles. During isometric contractions of frog single fibers, a rampstretch of varied velocity (amplitude, 0.02 fiber length; velocity,0.08-1.0 fiber length/s) followed by a release (amplitude, 0.02 fiber length; velocity, 1.0 fiber length/s) was given, and the amountof work liberated during the release was measured. For human muscles,elbow flexions were performed with a prestretch of variedvelocity (range, 40°; velocity, 30-180°/s) followed by anisokinetic shortening (velocity, 90°/s). In both frog single fibersand human muscles, the work production increased with both the velocityof stretch and the peak of force attained before the release up to acertain level; thereafter it declined with the further increases ofthese variables. In human muscles, the enhancement of work productionwas not associated with a significant increase in integratedelectromyogram. This suggests that changes in intrinsic mechanicalproperties of muscle fibers play an important role in thestretch-induced enhancement of work production. 相似文献
1000.
Sachi Sri Kantha Shun-ichi Wada Masao Takeuchi Shugo Watabe Hirotomo Ochi 《Biotechnology Techniques》1996,10(12):933-936
Summary Representative endogenous antioxidants and natural food extracts were screened for hydroxyl radical scavenging activity by an ELISA. Whereas conventional assays for hydroxyl radical scavenging activity use either spin traps following the induction of Fenton reaction or measure thiobarbituric acid-reactive substances, this assay measures 8-hydroxy deoxyguanosine liberated from the hydroxylation of deoxyguanosine by Cu2+/ascorbate system. 相似文献