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21.
Application of an enzyme-linked immunosorbent assay for screening of T-2 toxin-producing Fusarium spp. 总被引:1,自引:1,他引:0
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S Nagayama O Kawamura K Ohtani J C Ryu D Latus L Sudheim Y Ueno 《Applied microbiology》1988,54(5):1302-1303
Culture filtrates of Fusarium species were subjected without clean-up procedures to an indirect competitive enzyme-linked immunosorbent assay with anti-T-2 toxin monoclonal antibody. Fusarium sporotrichioides, F. poae, F. tricinctum, and F. culmorum strains were positive for T-2 toxin, with a minimum detection limit of 5 pg per assay (100 pg/ml of culture filtrate), and the assay data correlated well with the gas-liquid chromatographic data. 相似文献
22.
The possible involvement of phosphodiesterase (PDE) activation in phototransduction was investigated in gecko photoreceptors by comparing the in situ PDE activity with the photoreceptor potential. In the dark, intracellular injection of cGMP into a gecko photoreceptor caused a long-lasting depolarization. An intense light flash given during the depolarization phase repolarized the cell with a short latency comparable to that of the light-evoked hyperpolarizing response, which indicates that the activation of PDE in situ is rapid enough to generate the photoreceptor potential. PDE activity in situ was estimated quantitatively from the duration of the cGMP-induced depolarization, since it was expected that the higher the PDE activity, the shorter the duration. Under steady illumination, the enzyme exhibited a constant activity. On exposure to a light flash, PDE became activated, but recovered in the dark with a time course that was dependent on the intensity of the preceding stimulus. When PDE activity and photoreceptor sensitivity to light were measured in the same cell after a light flash, both recovery processes showed similar kinetics. Theoretical analysis showed that the parallelism in the recovery time courses could be explained if cGMP is the transduction messenger. These results suggest that PDE activation is involved not only in the generation but also in the adaptation mechanisms of the photoreceptor potential. 相似文献
23.
H Z Streicher F Cuttitta G K Buckenmeyer H Kawamura J Minna J A Berzofsky 《Journal of immunology (Baltimore, Md. : 1950)》1986,136(3):1007-1014
A panel of syngeneic monoclonal anti-idiotypic antibodies was prepared by immunizing A.SW mice with keyhole limpet hemocyanin-coupled A.SW monoclonal anti-myoglobin (HAL 19, IgG1) and screening the cloned hybridomas for production of IgG2 binding to idiotype but not to certain other anti-myoglobin antibodies of the same subclass in an ELISA. With these antibodies, we identified three nonoverlapping idiotopes, based on three clusters of monoclonal anti-idiotopes that mutually inhibit within each cluster, but not between clusters (Cluster I: S2, S6, S8; Cluster II: S5, S7; Cluster III: S9). Only Cluster II antibodies block the binding of myoglobin to HAL 19 and so identify a binding site-related idiotope(s). Binding of both Cluster II monoclonals (S5 and S7) to Hal 19 is inhibited by a rabbit anti-idiotype that we previously reported detects a common cross-reactive anti-myoglobin idiotope in immune sera. However, only one of these, S7, and not S5, identifies an idiotope that is present on 20 to 30% of A.SW anti-myoglobin antibodies in immune sera and ascites. The panel of syngeneic monoclonal anti-idiotype antibodies also detects new idiotopes not detected by the rabbit anti-idiotype. The development of a panel of syngeneic monoclonal anti-idiotypic antibodies to different clusters of idiotopes on the same antibody molecule, including one that identifies a major common idiotope in immune sera, should allow the analysis of possible idiotype network regulation in vivo and in vitro in a completely syngeneic system. 相似文献
24.
Kimitoshi Umeda Hideki Tateda 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1985,157(6):831-836
Summary The physiology and morphology of visual interneurons in the lobula complex of the fleshfly,Boettcherisca peregrina, were studied using intracellular recordings and intracellular cobalt stainings, respectively. Using responses to movements of a spot of light and on-off stimuli at single positions, we classified the interneurons into five physiological groups ON, OFF, ON-OFF, nondirectional motion sensitive (NDM) and directional motion sensitive (DM) neurons. They could be further divided into four morphological types, depending on the location and extent of their dendrites and terminal branches. 相似文献
25.
26.
Long-term follow-up study of rostral mesencephalic reticulotomy for pain relief--report of 34 cases 总被引:1,自引:0,他引:1
K Amano H Kawamura T Tanikawa H Kawabatake M Notani H Iseki T Shiwaku T Nagao Y Iwata T Taira 《Applied neurophysiology》1986,49(3):105-111
A long-term follow-up study of rostral mesencephalic reticulotomy (RMR) for pain relief is presented. 34 patients (24 males and 10 females) were operated. Ages ranged from 18 to 65 years. The follow-up period was 1-70 months. The overall effectiveness of RMR showed good relief of pain in 23 patients (67%). The study of effectiveness of RMR according to type of pain showed good relief of pain in 5 out of 6 patients (83%) with nondenervation pain, whereas satisfactory pain relief was obtained in 18 out of 28 patients (64%) with denervation pain. 相似文献
27.
Hideki Ozawa Takao Iwaguchi Tateshi Kataoka 《Cancer immunology, immunotherapy : CII》1986,23(1):73-77
Summary Spleen cells of BALB/c mice hyperimmunized with a transplantable methylcholanthrene-induced sarcoma Meth A (Meth A-Im-SPL) inhibited the growth of Meth A tumor in vivo in a tumor neutralizing test. Meth A-Im-SPL did not neutralize another antienically distinct sarcoma, Meth 1, indicating that the antitumor activity is tumor specific. Lyt-1+2– cells of Meth A-Im-SPL (Im-Lyt-1+2–) were the effectors since in vitro treatment of Meth A-Im-SPL with anti-Thy 1.2 or anti-Lyt 1.2 antibody plus complement completely abrogated their neutralizing activity, whereas treatment with anti-Lyt 2.2 plus complement did not. To further confirm the effector activity of Im-Lyt-1+2– cells, T cell subpopulations were separated from Meth A-Im-SPL by the panning method. The purified Im-Lyt-1+2–, but not Im-Lyt-1+2+ cells neutralized the tumor in athymic nu/nu mice as efficiently as in +/+ mice, suggesting that the donor Im-Lyt-1+2– cells but not recipient T cells were primarily responsible for neutralizing the tumor. The present study, however, did not exclude the possible contribution of recipient T cells to the tumor neutralization and this is open to further investigation.Abbreviations Meth A-Im-SPL
Meth A-immune mouse spleen cells
- Meth 1-Im-SPL
Meth 1-immune mouse spleen cells
- sIg+ cells
surface immunoglobulin positive cells
- moAb
monoclonal antibody 相似文献
28.
Transductional Analysis of the leu-thr Region of Chromosome of Serratia marcescens 总被引:2,自引:0,他引:2
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Transductional analysis of the chromosomal linkage map of Serratia marcescens near leu revealed the following order of loci: ser4-thr3-pyr1-pdx2-leu1-azi8. 相似文献
29.
Induced optical activity in poly-L-lysine-methyl orange system 总被引:1,自引:0,他引:1
The absorption and cicular dichroism spectra of the complex of poly-L -lysine (PLL) in the random coil form with methyl orange (MO) have been measured in aqueous solution. A new absorption band is observed at the shorter wavelength compared with that of the free dye. Although MO does not show a formation of dimer or aggregation with an increase in concentration, circular dichroism bands are observed at the wavelength corresponding to the wavelength of the new absorption band. These induced circular dichroism bands may arise from the dimeric MO molecules bound to PLL in the random coil form. The main contribution to the interaction between MO molecules is shown to be the electro static interaction. The observed circular dichroism spectra and the configuration of dimeric MO molecules bound to PLL can be explained by the dipole couping mechanism. 相似文献
30.
The electrical responses of the taste cell of the rat to chemical stimuli were studied by means of microelectrode techniques. Although large positive potential changes in the taste cell were usually elicited by taste stimuli, the response was a small negative potential change with respect to surrounding tissues if the microelectrode was thrust deeply into the taste bud. Both FeCl3 and cocaine produced a positive change in the steady potential. If this new potential is larger than a certain equilibrium potential, reversal of the polarity of the potential change caused by a taste stimulus is observed. Gamma-aminobutyric acid and acetylcholine had no effect on the receptor steady potential nor on the receptor responses elicited by taste stimuli. 相似文献