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991.
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
992.
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
993.
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
994.
A rapid and accurate method based on multiplex PCR using three different primers was developed for determining mating type
inCochliobolus heterostrophus. The primers of MAT113 and MAT123 were uniquely derived fromMAT1-1 andMAT1-2, respectively, and the primer MATcon5 is conserved in the flanking regions of the idiomorphs. The amplification product was
estimated to be 702 bp (MAT1-1) or 547 bp (MAT1-2). Crossing experiments confirmed the accuracy of this method, which requires less time than the conventional determination
of mating type. 相似文献
995.
A novel type of zygospore formation is described in the heterothallic speciesMortierella capitata, which was repeatedly isolated from soils inhabited by pillbugs (Armadillidium vulgare, Isopoda). Zygospore formation was induced on media containing sterilized arthropods. Anisogamy and colorless zygospore walls
are shared with other zygosporic species ofMortierella, but a unique feature ofM. capitata is the production of zygospores on elongated macrosuspensors which are covered by branches of the microsuspensors. This kind
of zygosporogenesis is termed “capitata-type” here. The taxonomic position ofM. capitata is discussed based on the zygospore characteristics. 相似文献
996.
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
997.
998.
Seiji Okazaki Yoshihiko Nishida Hisaomi Kawai Shiro Saito 《Neurochemical research》1996,21(10):1201-1207
We examined the effect of the glutamate uptake inhibitorl-trans-pyrrolidine-2,4-dicarboxylic acid (PDC) on the neurotoxicity ofl-glutamate in organotypic cultures of rat spinal cord. Eighteen-day-old cultures were incubated with 500 μMl-glutamate, 1 mM PDC, or both. After 72 hours, the tissues were stained for acetylcholinesterase (AChE), and the ventral horn
AChE-positive neurons (VHANs) analyzed using morphometry. Neitherl-glutamate nor PDC affected AChE staining, but in combination they produced markedly reduced AChE staining in the dorsal horn
and a significant decrease in the number of VHANs (especially the smaller VHANs) as compared with the control. Moreover, treatment
with 200 μM PDC for 2 weeks preferentially affected the smaller VHANs. The neurotoxicity ofl-glutamate plus PDC was blocked by the N-methyl-d-aspartate (NMDA) antagonist 3-((RS)-2-carboxypiperazin-4-yl)-propyl-1-phosphonic acid (CPP).
Results suggest that glutamate uptake system has an important protective function in the aggravation of acute neuronal damage. 相似文献
999.
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
1000.