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81.
Yoshiyuki Kawakami Ichiro Ueno Tsutomu Katsuyama Ken'ichi Furihata Hideki Matsumoto 《Microbiology and immunology》1994,38(11):891-895
Epidemiological typing, based on restriction fragment length polymorphism (RFLP) by pulsed-field gel electrophoresis (PFGE), was attempted for the 38 clinical isolates of Moraxella catarrhalis obtained at Shinshu University Hospital during the years 1987 and 1993. Digestion with SmaI or NotI generated well separable, 12 to 5 genomic DNA fragments ranging from 1,000 kb to 30 kb and the strains could be classified into 14 or 13 types, respectively. The electrophoretic profile differed with the strain in most of them and was hence useful to distinguish the each strain. Investigation for their RFLP have, however, suggested that majority of them, including the type strain ATCC25238, may have derived from a common ancestor. 相似文献
82.
Benzyladenine-induced changes in the translatable mRNA population in excised cucumber cotyledons 总被引:2,自引:0,他引:2
Benzyladenine-induced changes in the translatable mRNA population in excised cucumber cotyledons were studied. Poly (A)+ RNA was prepared from etiolated cotyledons incubated with or without benzyladenine (BA) for various periods in the dark. Using nonequilibrium pH gradient electrophoresis-SDS polyacrylamide gel electrophoresis and isoelectric focusing-SDS polyacrylamide gel electrophoresis, both basic and neutral proteins translated in vitro were separated. About 240 spots were detected and 16 of them changed within 6 h after BA application. Some spots changed quickly (within 1–2 h). Among them, three were repressed markedly 相似文献
83.
Takeo Uchiyama Masuro Numata Seiji Terada Tsutomu Hosino 《Plant Cell, Tissue and Organ Culture》1993,32(2):153-159
A suspension culture of Mentha was established from callus which formed on the tips of young shoots of a Mentha hybrid (M. arvenis × M. spicata). Changes in growth parameters during a culture cycle were recorded. The general appearance of cells during division and growth, including the changes in cell form, was also represented.Suspension-cultured cells of Mentha hybrid released a large amount of extracellular polysaccharides (ECP) mainly at the logarithmic phase of the growth cycle. The ECP contained galacturonic acid as major components and arabinose, galactose, glucose, xylose, rhamnose and mannose as minor components. The ratio of the uronic acid content to total sugar content in the ECP was below 40% at day 7, but increased up to 90% at day 21. The relative contents of xylose and glucose in the ECP decreased during the culture period, while the arabinose content increased and those of rhamnose, mannose and galactose remained constant.The IR spectrum suggested that the ECP were low-methoxylated pectic polysaccharides. The presence of lignin and related compounds in the ECP was not detected. The protein content of the ECP was about 10% and the main amino acids were alanine, proline, hydroxyproline, valine, asparticacid and serine, in that order. 相似文献
84.
Tsutomu Araki Hiroyuki Kato Yasuo Kanai Kyuya Kogure 《Neurochemistry international》1993,23(6):541-548
Age-related alterations in major neurotransmitter receptors and voltage dependent calcium channels were analyzed by receptor autoradiography in the gerbil brain. [3H]Quinuclidinyl benzilate (QNB). [3H]cyclohexyladenosine (CHA), [3H]muscimol, [3H]MK-801, [3H]SCH 23390, [3H]naloxone, and [3H]PN200-110 were used to label muscarinic acetylcholine receptors, adenosine A1 receptors, γ-aminobutyric acidA (GABAA) receptors,
(NMDA) receptors, dopamine D1 receptors, opioid receptors, and voltage dependent calcium channels, respectively. In middle-aged gerbils (16 months old), the hippocampus exhibited a significant elevation in [3H]QNB, [3H]MK-801, [3H]SCH 23390, [3H]naloxone, and [3H]PN200-110 binding, whereas [3H]CHA and [3H]muscimol binding showed a significant reduction in this area, compared with that of young animals (1 month). On the other hand, the cerebellum showed a significant alteration in [3H]QNB, [3H]CHA, and [3H]naloxone binding and the striatum also exhibited a significant alteration in [3H]SCH 23390 and [3H]CHA binding in middle-aged gerbils. The neocortex showed a significant elevation only in [3H]CHA binding in middle-aged animals. The nucleus accumbens and thalamus also showed a significant alteration only in [3H]muscimol binding. However, the hypothalamus and substantia nigra exhibited no significant alteration in these bindings in middle-aged gerbils. These results demonstrate the age-related alterations of various neurotransmitter receptors and voltage dependent calcium channels in most brain regions. Furthermore, they suggest that the hippocampus is most susceptible to aging processes and is altered at an early stage of senescence. 相似文献
85.
Isao Sakita Takushi Monden Hirohito Nagaoka Yoshihiro Katsumoto Taro Wakasugi Naohiro Tomita Tsutomu Takeda Tetsuro Kobayashi Takashi Shimano Takesada Mori 《Biotherapy》1993,6(2):103-112
We have previously reported that the antitumor effect of OK-432, a streptococcal preparation, is markedly augmented when injected intratumorally together with fibrinogen (OK-432/fbg) [1]. In order to elucidate the effects of this immunotherapy on regional lymph nodes (RLN), we carried out both morphological and functional analyses of the RLN from colonic cancer patients treated with OK-432/ fbg. Computer-aided morphometry revealed that the maximal cross-sectional areas and the broadest diameters of the RLN were significantly greater (p<0.01) in patients who had undergone local immunotherapy than in patients who had not. The component structures of RLN, such as sinus, follicle and paracortex, were all enlarged in the OK-432/fbg-treated patients, and necrosis of metastatic tumors was observed. RLN lymphocytes recovered from OK-432/fbg treated patients showed elevated reactivity to phytohemagglutinin (PHA) and the stimulation index was clearly higher than that of control patients. Flow cytometric analysis revealed a predominance of T-cells, especially CD4 subsets, and higher positivity for both CD25 and HLA-DR. Furthermore, RLN lymphocytes killed more effectively K562 and Daudi cells in the patients who had had immunotherapy. These results suggest that the effect of local immunotherapy with OK-432/fbg is not restricted to the site of injection but extends to the lymph nodes, and contributes to tumor regression through the augmentation of cellular immunity.Abbreviations RLN
regional lymph node(s)
- OK-432/fbg
OK-432/fibrinogen solution
- PHA
phytohemagglutinin
- NK
natural killer
- LAK
lymphocyte activated killer 相似文献
86.
Kazuo Sakamoto Kazuhiro Fujita Kimiko Hirayae Kumiko Iida Takashi Koyano Yoshihisa Asada Tsutomu Furuya 《Biotechnology Techniques》1993,7(10):749-754
Summary An integrated system has been constructed to instantly identify and efficiently sort the heterokaryons formed by plant protoplast fusion. The system is composed of the following functions: a) a transport system, b) an electro-manipulator, c) a cell harvester, d) a flow cytometer/cell sorter, and e) a control device. The conditions for an efficient and reproducible enrichment of the heterokaryons have been investigated by this system using the fluorescein isothiocyanate stained protoplasts preparing from Glycyrrhiza glabra cell cultures and unstained protoplasts of Abrus precatorius cell cultures which contain a large quantity of chlorophyll.Abbreviations MS
Murashige and Skoog (1962)
- 2,4-D
2, 4-dichlorophenoxyacetic acid
- NAA
1-naphthaleneacetic acid
- BAP
6-benzylaminopurine
- ABA
abscissic acid
- FITC
fluorescein isothiocyanate
This paper is part 96 in the series Studies on Plant Tissue Cultures. For part 95 see Orinara Y., Noguchi T. and Furuya T. (1993) submitted for publication. 相似文献
87.
Cytokinin-binding protein (CBPI) was purified from the watersoluble fraction of tobacco leaves by successive chromatographyon benzyladenine-linked (BA-linked) Sepharose 4B, TSK-Gel G3000SWXL,t-zeatin-linked Sepharose 6B and TSK-Gel G3000SWXL. CBPI wasobtained as a monomer with a molecular weight of 31 kDa. Ithas one cytokinin-binding site, which shows a high affinityfor BA (Kd=1.1x107 M) and other cytokinins. Biologicallyactive cytokinins competed with BA for binding to this protein,while biologically inactive analogues of adenine did not. Inall cases, cytokinin-binding activity was assayed by equilibriumdialysis.
1 Present address: National Institute for Basic Biology, Okazaki,444 Japan. 相似文献
88.
Rice (Oryza sativa L. cv. Yamabiko) seedlings germinated underwater for 5 days contained small amounts of heme a and protohemebut no protochlorophyll(ide) [Pchl(ide)]. Levels of hemes andPchl(ide) increased rapidly upon transfer to air. When expressedin terms of fresh weight of tissue, hemes reached the levelsin aerobic controls after 24 h of contact with air, but Pchl(ide)did not. A comparison of the increases during 24-h adaptationto air in levels of heme a and Pchl(ide), which are specificto mitochondria and plastids, respectively, suggested that thedevelopment of mitochondria preceded that of plastids. The rateof synthesis of 5-aminolevulinic acid (ALA) was low in submergedseedlings, as compared to the rate in aerobic controls, butit increased during air adaptation. The sum of the amounts ofheme a, protoheme and Pchl(ide) increased in parallel with theamount of porphyrins, equivalent to the amount of ALA synthesizedduring the experimental period. When submerged seedlings thathad been pretreated with levulinic acid were exposed to air,no Pchl(ide) was formed. In contrast, Pchl(ide) accumulatedunder water when submerged seedlings were fed with ALA. Theseresults indicate that the synthesis of ALA, the limiting stepin the synthesis of Pchl(ide), is repressed under hypoxic conditions.
1 Present address: KRI International, Inc., Kyoto Research Park17, Chudoji Minami-machi, Shimogyo-ku, Kyoto, 600 Japan.
2 Present address: Research Institute for Bioresources, OkayamaUniversity, Kurashiki, 710 Japan. 相似文献
89.
Yuko Kumeda Tsutomu Asao Haruo Takahashi Masakazu Ichinoe 《FEMS microbiology ecology》2004,47(2):263-263
90.
Kanako Yoshizawa Kyoko Inaba Hideyuki Mannen Tateki Kikuchi Makoto Mizutani Soichi Tsuji 《Experimental Animals》2003,52(5):391-396
Despite intensive studies of muscular dystrophy of chicken, the responsible gene has not yet been identified. Our recent studies mapped the genetic locus for abnormal muscle (AM) of chicken with muscular dystrophy to chromosome 2q using the Kobe University (KU) resource family, and revealed the chromosome region where the AM gene is located has conserved synteny to human chromosome 8q11-24.3, where the beta-1 syntrophin (SNTB1), syndecan 2 (SDC2) and Gem GTPase (GEM) genes are located. It is reasonable to assume those genes might be candidates for the AM gene. In this study, we cloned and sequenced the chicken SNTB1, SDC2 and GEM genes, and identified sequence polymorphisms between parents of the resource family. The polymorphisms were genotyped to place these genes on the chicken linkage map. The AM gene of chromosome 2q was mapped 130 cM from the distal end, and closely linked to calbindin 1 (CALB1). SNTB1 and SDC2 genes were mapped 88.5 cM distal and 27.6 cM distal from the AM gene, while the GEM gene was mapped 18.5 cM distal from the AM gene and 9.1 cM proximal from SDC2. Orthologues of SNTB1, SDC2 and GEM were syntenic to human chromosome 8q. SNTB1, SDC2 and GEM did not correspond to the AM gene locus, suggesting it is unlikely they are related to chicken muscular dystrophy. However, this result also suggests that the genes located in the proximal region of the CALB1 gene on human chromosome 8q are possible candidates for this disease. 相似文献