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81.
82.
Marianne J. Huisman Erik Jongedijk Dinie Posthumus-Lutke Willink Frank Van Der Wilk Ben J. C. Cornelissen 《European journal of plant pathology / European Foundation for Plant Pathology》1992,98(2):29-36
To engineer resistance against potato virus X (PVX), the viral coat protein (CP) gene has been introduced into two potato cultivars. Stable expression of the gene in transgenic clones throughout the growing season has been obtained and resulted in considerably increased virus resistance. With varying frequencies depending on the original cultivar used, true-to-type PVX resistant transgenic clones have been obtained. Since deviant light sprout characteristics were invariably associated with aberrations in plant phenotype, they can be used in procedures to early screen for deviations. Furthermore, it has been possible to unequivocally discriminate between the original untransformed and independent transgenic cultivars. Although no relation has been found between the presence, if any, of the CP of potato virus Y (PVY) or potato leafroll virus (PLRV) in CP gene transgenic potato, appreciable levels of resistance to these viruses has been obtained. This suggests that the mechanism by which a viral CP gene in the potato genome evokes resistance, differs amongst various viruses. 相似文献
83.
Hiromi Takahashi Chieko Kai Yasuhiro Yoshikawa Kazuya Yamanouchi 《Comparative immunology, microbiology and infectious diseases》1995,18(4):275-281
Pseudorabies virus (PRV) was inoculated intraocularly into BALB/c mice, and the distribution pattern of cells positive for several neurotransmitters and viral antigens in the eyeball, trigeminal nerve ganglia, and superior cervical ganglia was examined immunohistochemically to clarify the neural route of the virus spread. In the eyeball, substance P (SP)- and calcitonin gene-related peptide (CGRP)-positive cells were detected in the ipsilateral iris and ciliary body, neuropeptide tyrosine (NPY)-positive cells were detected in the choloid membrane, and tyrosine hydroxylase (TH)-positive cells were detected in the ipsilateral inner nuclear layer of the retina; all these cells contained viral antigens. In the superior cervical ganglia, viral antigen-positive cells containing TH or NPY were found at bilateral sites. In the trigeminal nerve ganglia, viral antigen-positive cells containing SP or CGRP were found at bilateral sites. These findings indicated that the SP- and CGRP-positive ganglion cells of the trigeminal nerve ganglia innervating the iris or ciliary body, and the NPY-positive ganglion cells of the superior cervical ganglia innervating the iris, ciliary body, and choroid membrane served as the route for the virus spread. These findings also suggested that dopaminergic neurons, such as the TH-positive retinal cells and TH-positive ganglion cells of the superior cervical ganglia, served as the route for virus spread. 相似文献
84.
O. M. van Andel 《European journal of plant pathology / European Foundation for Plant Pathology》1968,74(1):113-120
Experiments on the effect of various compounds with plant growth regulating activity led to the hypothesis that conditions inhibitory to indoleacetic acid (IAA) action or leading to a decrease in the IAA level in cucumber seedlings would be unfavourable for the development of cucumber scab, caused byCladosporium cucumerinum. Susceptibility decreased as the result of treatment with growth retardants, which cause an increase in IAA-oxidase activity in the plants, whereas application of indoleacetic acid or compounds expected to decrease the rate of oxidative breakdown of IAA in the seedlings resulted in an increase of susceptibility. Growing the plants under various periods of illumination also influenced both the susceptibility of the plants and the IAA-oxidase activity in the hypocotyl tissue.To obtain further information about the relation between the increase in resistance and the increase in the rate of IAA oxidation, the effect of one compound, viz. L-threo-β-phenylserine (abbr. phenylserine) was studied in more detail. The rate of oxidative breakdown of IAA was increased in extracts of hypocotyls and cotyledons of plants treated with phenylserine as compared with extracts of tissue of untreated plants. Extracts of phenylserine-treated plants were found to contain a higher cofactor and/or a lower inhibitor content than those of control plants. The substances involved were not identified, but this result may indicate a shift in the concentrations of various phenols in the tissue.The question must remain open whether a shift in the concentration of phenols some-how effected by phenylserine treatment determines both degree of susceptibility and rate of IAA oxidation independently, or whether the rate of IAA breakdown and the resulting change in IAA content in the plants is directly related to the degree of susceptibility. 相似文献
85.
Itagaki T Tsumagari N Tsutsumi K Chinone S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(8):931-933
Three bovine amphistomes, Calicophoron calicophorum, Orthocoelium streptocoelium and Homalogaster paloniae, are common in Japan. This study was carried out to describe ITS2 sequences in the 3 species, and to evaluate a PCR-RFLP technique based on ITS2 sequence for the species identification in single eggs of the parasites. The ITS2 sequences of the three species contained 19 variable sites including one gap. The sequence difference between species was 4.2-5.3%. The three species of amphistomes were identified based on the difference in the restriction sites of Acc II on the ITS2 sequence. 相似文献
86.
Tsutsui T Hori T Yamada A Kirihara N Kawakami E 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(5):659-661
The number of spermatozoa required to obtain conception by intratubal insemination in dogs was examined. Three groups consisting of 5, 8 and 8 dogs received 0.5 x 10 (6), 2.0 x 10(6) and 4.0 x 10(6) spermatozoa, respectively, into each uterine tube. No conception occurred in the 5 animals inseminated with 0.5 x 10(6) spermatozoa, but conception occurred in 6/8 (75.0%) and 3/8 (37.5%) dogs inseminated with 2.0 x 10(6) and 4.0 x 10 (6) spermatozoa, respectively. Among the pregnant animals, three aborted (33.3%) and the mean number of newborns was small, 2.5 +/- 0.5 (SE). One acardiacus anceps was observed with normal fetus in one animal with a Caesarean delivery. 相似文献
87.
Isothermal amplification of rabies virus gene 总被引:1,自引:0,他引:1
88.
Kentaro Okuno Tomoko Hama Minoru Takeshita Naruto Furuya Yoichi Takanami 《Journal of General Plant Pathology》2003,69(2):138-142
A potyvirus, for which the name Japanese hornwort mosaic virus (JHMV) is proposed, was isolated from Japanese hornwort plants
(Cryptotaenia japonica) with mosaic disease symptoms. The virus was used to inoculate mechanically 34 plants belonging to 33 species of 10 families.
Of these species seven from two families were infected. Faint chlorotic spots appeared on the inoculated leaves of Chenopodium quinoa and C. amaranticolor, but no systemic infection occurred in these plants. JHMV systemically infected only Umbelliferae plants; they did not infect
26 other species in eight families. JHMV was transmitted in a nonpersistent manner by aphids (Myzus persicae). The virus was a flexuous rod-shaped particle about 750 nm in length. Sequencing the nucleotides in the 3′ terminal region
of JHMV revealed that the coat protein contains 280 amino acids with a molecular mass of 32.2 kDa. The nucleotide sequence
of the coat protein of JHMV had the highest similarity with that of Zantedeschia mosaic virus (83.3%) compared to those of
other potyviruses (57.0%–64.9%). An antiserum against JHMV reacted strongly with JHMV and weakly with Potato virus Y. These results indicate that JHMV is a new potyvirus.
Received: September 9, 2002 / Accepted: November 7, 2002
RID="*"
ID="*" The nucleotide sequence determined in this work appears in the DDBJ/EMBL/GenBank nucleotide sequence databases with
the accession number AB081518 相似文献
89.
Kurotaki T Narayama K Arai Y Arai S Oyamada T Yoshikawa H Yoshikawa T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(6):539-541
Histopathologic and electron microscopic observations were given on Langerhans cells (LCs) within the follicular epithelium (FE) and intradermal sweat duct (ISD) of equine "Kasen". By light microscopy, LCs were present in the greatest numbers within the FE and ISD than within the epidermal layer and the normal skin, with an occasional formation of several aggregated foci. By electron microscopy, LCs within the FE and ISD widely extended their dendritic processes between the keratinocytes and contained Birbeck granules (Bgs), mitochondria, rough endoplasmic reticula and ribosomes in the cytoplasm. Numerous Type 2 LCs, with a number of Bgs and endocytosis, and Type 3 LCs, with multivesicular bodies and endosomes of various sizes, were recognized within the FE and ISD, although inactive Type 1 LCs, with a narrow and lucid cytoplasm, were rarely seen. LCs observed within the FE and ISD in the "Kasen" skin lesions might express the particular stage corresponded to recognize, intake and process the antigens which permeate them. 相似文献
90.
To investigate the action of dinotefuran (MTI-446, 1-methyl-2-nitro-3-(tetrahydro-3-furylmethyl)guanidine), a recently developed insecticide, on insect nicotinic acetylcholine receptors (nAChRs), we determined the potencies of the compound and 15 analogues in inhibiting the specific binding of [3H]epibatidine (EPI), a nAChR agonist, and [3H]alpha-bungarotoxin (alpha-BGT), a competitive nAChR antagonist, to the nerve cord membranes of American cockroaches (Periplaneta americana). Racemic dinotefuran inhibited [3H]EPI binding with an IC50 of 890 nM and [3H]alpha-BGT binding with an IC50 of 36.1 microM. Scatchard analysis indicated that the dinotefuran inhibition of [3H]EPI binding was a competitive one. Slight structural modification caused a drastic reduction in potency; only four analogues were found to be equipotent to or more potent than dinotefuran. Chloropyridinyl and chlorothiazolyl neonicotinoid insecticides displayed two or three orders of magnitude higher potency than dinotefuran. There was a good correlation between the IC50 values of tested compounds obtained with [3H]EPI and those obtained with [3H]alpha-BGT. A better correlation was observed between 3-h knockdown activities (KD50) against German cockroaches (Blattella germanica) and IC50 values obtained from [3H]EPI assays than between 24-h lethal activities (LD50) and IC50 values. While the results indicate that dinotefuran and its analogues interact with the ACh-binding site in cockroach nAChRs, it remains to be elucidated why they displayed lower potencies than those expected based on their insecticidal activities. 相似文献