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1.
L11A-Fukushima (L11A-F) derived from attenuated isolate LuA of Tomato mosaic virus (ToMV) has the highest ability to cross protect against virulent ToMV among LuA and its derivatives and is stably inherited. Growth, yield, fruit quality and symptom attenuation of inoculated tomato plants did not differ significantly between L11A-F and L11A. The infectivity of progeny viruses in tomato infected with LuA-F was less than 4% of that with virulent ToMV. From these results, L11A-F appears to possess the properties necessary for practical use. To manage L11A-F strictly, a PCR-based assay to detect trace contamination of virulent ToMV in L11A-F preparations was established. Received 10 June 2002/ Accepted in revised form 30 October 2002  相似文献   
2.
In order to determine the role of the cecum on energy use in growing chickens, metabolizability of the dietary energy and energy expenditure were examined in the week following bilateral ligation and washing out of the cecum. Apparent metabolizable energy (AME) values were 14.30 and 13.69 kJ/g air‐dry matter for sham‐operated and cecally ligated chickens, respectively. These values were found to be significantly different (P < 0.05). Although AME intake and fasting heat production were decreased by cecal ligation, the distribution of AME (measured as fasting and feeding heat production, as well as heat increment and energy retention, as a proportion of AME intake) was not affected. These results suggest that the cecum helps chickens extract AME from corn‐soybean type diets with little, if any, effect on AME use, based on the present study of growing chickens in the week following cecal ligation.  相似文献   
3.
A male Japanese domestic cat with retarded growth in Hokkaido, Japan, showed progressive motor dysfunction, such as ataxia starting at 3 months of age and tremors, visual disorder and seizure after 4 months of age. Finally, the cat died of neurological deterioration at 9 months of age. Approximately half of the peripheral blood lymphocytes had multiple abnormal vacuoles. Magnetic resonance imaging showed bisymmetrical hyperintensity in the white matter of the parietal and occipital lobes in the forebrain on T2-weighted and fluid-attenuated inversion recovery images, and mild encephalatrophy of the olfactory bulbs and temporal lobes. The activity of lysosomal acid β-galactosidase in leukocytes was negligible, resulting in the biochemical diagnosis of GM1 gangliosidosis. Histologically, swollen neurons characterized by accumulation of pale, slightly granular cytoplasmic materials were observed throughout the central nervous system. Dysmyelination or demyelination and gemistocytic astrocytosis were observed in the white matter. Ultrastructually, membranous cytoplasmic bodies were detected in the lysosomes of neurons. However, genetic analysis did not identify the c.1448G>C mutation, which is the single known mutation of feline GM1 gangliosidosis, suggesting that the cat was affected with a new variant of the feline disease.  相似文献   
4.
Tubulointerstitial nephritis antigen-like 1 (Tinagl1, also known as adrenocortical zonation factor 1 [AZ-1] or lipocalin 7) is a matricellular protein. Previously, we demonstrated that Tinagl1 expression was restricted to extraembryonic regions during the postimplantation period and detected marked expression in mouse Reichert’s membranes. In uteri, Tinagl1 is markedly expressed in the decidual endometrium during the postimplantation period, suggesting that it plays a physical and physiological role in embryo development and/or decidualization of the uterine endometrium during pregnancy. In the present study, in order to determine the role of Tinagl1 during embryonic development and pregnancy, we generated Tinagl1-deficient mice. Although Tinagl1–/– embryos were not lethal during development to term, homologous matings of Tinagl1–/– females and Tinagl1–/– males showed impaired fertility during pregnancy, including failure to carry pregnancy to term and perinatal lethality. To examine ovarian function, ovulation was induced with equine chorionic gonadotropin (eCG) and human chorionic gonadotropin (hCG); the number of ovulated oocytes did not differ between Tinagl1–/– and Tinagl1flox/flox. In vitro fertilization followed by embryo culture also demonstrated the normal developmental potential of Tinagl1-null embryos during the preimplantation period. Our results demonstrate that Tinagl1 deficiency affects female mice and results in subfertility phenotypes, and they suggest that although the potential of Tinagl1–/– oocytes is normal, Tinagl1 is related to fertility in adult females but is not essential for either fertilization or preimplantation development in vitro.  相似文献   
5.
Basidiocarps of the violet root rot fungus, Helicobasidium mompa, are less frequently used for isolation than are mycelial strands and sclerotia even though the basidiocarps are conspicuously produced at the trunk base of diseased plants. Basidiocarps are also more suitable for storage. This paper describes an improved method for obtaining pure cultures from basidiocarps using microcentrifuge tubes to facilitate the awkward steps of rinsing fungal materials under a dissecting microscope. Received 28 June 2000/ Accepted in revised form 4 August 2000  相似文献   
6.
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   
7.
Complement-mediated cytotoxicity for porcine islet cells (PICs) was evaluated using sera of six animal species. Then soluble complement receptor type-1 (sCR1) as an anti-complement agent was added to those sera, and the changes in 50% hemolytic unit of complement serum (CH50) and cytotoxic effect of those sera on PICs were examined. All the sera except for that of pig showed cytotoxicity. However, the extent of toxicity was considerably different between species. In the rat and human serum, sCR1 significantly reduced CH50 and cytotoxicity, however in the dog serum, sCR1 had no suppressive effects. These results may suggest that complement contribute to humoral cytotoxicity for PICs as a main factor, and the compatibility of complement with PICs differs between animal species.  相似文献   
8.
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   
9.
A modified rate equation, in which the diffusion of reagent was taken into consideration, was proposed and applied to results reported previously for the acetylation of wood. The equation was fitted more successfully to the prolonged as well as the early stage of the reaction than a common first-order rate equation. Although the conclusions were virtually unchanged, the reliability was enhanced because reaction parameters such as the rate constant, ultimate extent of the reaction, and activation energy calculated for the modified equation were based on much more data than those reported previously. The equation proposed here may be applicable not only to acetylation but to other chemical modifications of cellulosic materials in heterogeneous systems.  相似文献   
10.
Summary Using sulfur dioxide (SO2) as catalyst, wood specimens were treated with nonformaldehyde cross-linking reagents such as glyoxal, glutaraldehyde and dimethylol dihydroxy ethyleneurea (DMDHEU). The results of dimensional stability, acoustic properties, and mechanical strength tests were compared with those obtained from formaldehyde treatment. With glyoxal and glutaraldehyde treatments, antiswelling efficiency (ASE) reached around 70%, which is comparable to the values attained by formaldehyde treatment, although the accompanying weight gain was much larger than for the latter, whereas DMDHEU did not give sufficiently high ASE. None of the treatments, significantly increased specific dynamic Young's modulus (E/) with the exception of the DMDHEU treatment, loss tangent (tan ) decreased substantially, about 50 and 60% in longitudinal and radial directions respectively, which were somewhat exceeding the formaldehyde treatment. The results suggested that the improvement of the dimensional stability and acoustic properties is partly attributed to the formation of cross-links.  相似文献   
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