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121.
Ikeda Y Miyazawa T Nishimura Y Nakamura K Tohya Y Mikami T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(3):287-289
To know the genetic changes of feline immunodeficiency virus (FIV) in long-term infection in cats, we inoculated three specific pathogen-free cats with FIV isolates and determined a partial env sequence covering the V3-V5 region. In 2 cats infected with subtype B strains TM1 and TM2, only one amino acid change in region V3 was observed at 9 years post infection (y.p.i.), and no nucleotide substitutions were observed between 9 and 10 y.p.i., indicating that these strains are genetically stable. On the other hand, in a cat infected with subtype A strain Petaluma at 8.7 y.p.i., 3 nucleotide insertions (one amino acid insertion) in region V5, and 1 synonymous nucleotide substitution and 2 non-synonymous nucleotide substitutions in region V5, were observed. 相似文献
122.
Matsuda K Kobayashi S Yamashita M Hirayama K Kadosawa T Taniyama H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(5):479-481
Sarcomatous proliferation of spindle cells was present in the mammary gland and many metastatic sites in a 10-year-old female domestic cat with tubulopapillary carcinoma in the mammary gland. Transition from neoplastic tubular structures to spindle cells in the primary site and fascicular proliferation of the spindle cells with or without coexistance of tubulopapillary carcinoma in the primary and metastatic sites were observed. Most of spindle cells were positive for cytokeratin CAM5.2 as well as the normal luminal epithelium but not the myoepithelium. From these results, this case was diagnosed as tubulopapillary carcinoma with spindle cell metaplasia and it was clarified that neoplastic luminal epithelial cells can transform to sarcomatous appearence. 相似文献
123.
Kazuya Takai Tomoyuki Soejima Toshio Suzuki Kazuyoshi Kawazu 《Pest management science》2000,56(10):937-941
In order to develop an effective trunk‐injection agent against pine wood nematode, Bursaphelenchus xylophilus, an in vitro assay was used to examine the antinematodal activity of 58 commercially available compounds with known modes of action. Among compounds tested, the GABA receptor agonists had better anti‐nematodal activity than compounds influencing glutamate, N‐methyl‐D ‐aspartate, β‐adrenergic, dopamine, muscarinic acetylcholine and nicotinic acetylcholine receptors, as well as those inhibiting acetylcholinesterase, monoamine oxidase, 5‐hydroxytryptamine uptake and Ca2+, K+, Na+ and Cl− channels. Avermectins and milbemycins strongly inhibited propagation of the nematode. Emamectin benzoate proved to be the most active (IC95 0.050 µM ) being over 140 times more active than the active ingredient of conventional trunk‐injection agents. It is concluded that emamectin benzoate is a strong candidate for an anti‐nematodal trunk injection agent. © 2000 Society of Chemical Industry 相似文献
124.
Spruce wood blocks were acetylated in the presence of potassium acetate (KAc) at 20, 40, 60, 80 and 120°C. At 20°C, the weight percent gain (WPG) due to the KAc-catalyzed acetylation reached 20% in 18 days, whereas that due to pyridine-catalyzed acetylation did not exceed 8%. The hygroscopicity and dimensional stability of the KAc-acetylated wood were the same as those of conventionally acetylated wood at the same WPG, irrespective of reaction temperature. These facts suggest that the KAc enables simplified acetylation of wood at room temperature. The activation energy (E a) of the KAc-acetylation in the lower temperature range (20–40°C, 121–131 kJ/mol) was comparable to that of the acetylation of wood meal (140–146 kJ/mol). It was speculated that diffusion became a minor factor at reduced reaction rates in the lower temperature range, thus requiring a greater E a. 相似文献
125.
Md Qumruzzaman Chowdhury Futoshi Ishiguri Kazuya Iizuka Yuuya Takashima Kahoru Matsumoto Tokiko Hiraiwa Megumi Ishido Hiroyuki Sanpe Shinso Yokota Nobuo Yoshizawa 《Journal of Wood Science》2009,55(2):139-143
Radial variations of wood properties (basic density, fiber length, vessel element length, and compression strength) in plantation-grown
Casuarina equisetifolia in Bangladesh were investigated for effective utilization of the wood. Samples disks at breast height were randomly collected
from trees in a 10-year-old plantation in Cox’s Bazar Forest Division, Bangladesh. The basic density showed a near-constant
value up to 30 mm from the pith and then rapidly increased up to 60 mm from the pith. The fiber length and vessel element
length gradually increased from the pith to bark. When radial variation of wood properties was determined according to relative
distance from the pith, similar radial patterns were observed among the sample trees, indicating that the wood properties
in C. equisetifolia may be related to the growth rate. The compression strength parallel to the grain (CS) increased from the pith to bark. A
significant positive correlation was found between the air-dried density and the CS. The results obtained indicated that wood
around the pith has a relatively low density, and wood outside the pith area has a relatively high density, suggesting that
it could be used as structural lumber.
Part of this report was presented at the 58th Annual Meeting of Japan Wood Research Society, Tsukuba, March 2008 相似文献
126.
127.
Relations between various extracted basic densities and wood chemical components were investigated by their within-tree variations in Eucalyptus globulus for assistance in the prediction of the properties of wood or wood-derived products. Extraneous compounds affect the relations between various basic densities and wood chemical components such as holocellulose and the lignin syringyl/guaiacyl ratio. We also discuss the relation of various densities, the molar composition of neutral sugars constituting hemicellulose, and fiber morphology. 相似文献
128.
Pernambuco (Guilandina echinata Spreng. syn Caesalpinia echinata Lam.), which has been used for a material of violin bows, was compared with substitutable wood species from the viewpoint of processing properties and durability. The properties required for bow material are discussed. The shearing strength of pernambuco was higher than that of the other wood species at the same specific gravity. High shearing strength seems to be effective for preventing damage to the head (top part) of the bow. The presence of extractives affects the thermal softening of wood material, but ease of handling and permanent retention of form are not particularly superior for pernambuco, although it does have a high extractives content. A peculiarly low loss tangent (tan S) of pernambuco can probably be attributed to the large amount of extractives, rather than the mean microfibril angle.Part of this report was presented at the 46th Annual Meeting of the Japan Wood Research Society in Kumamoto, April 1996. 相似文献
129.
Kazuya Suzuki 《Soil Science and Plant Nutrition》2013,59(4):1003-1007
The influence of continuous application of compost and fertilizer on soil macroaggregation in a field subjected to long-term (ca. 20 years) double cropping (rice and barley) was investigated. Soil samples were collected from 4 different plots: a) No-NF, fertilizer containing P and K but no N; b) F, fertilizer containing N, P, and K; c) F+ LC, fertilizer plus low rate of compost; and d) F+ HC, fertilizer plus high rate of compost. The application of compost and fertilizer increased the degree of macroaggregation (>0.25 mm), the contents of organic C, total N, hydrolyzable carbohydrates, and dithionitecitrate-bicarbonate (DCB) soluble Al, and the hyphal length in the order of No-NF<F<F+LC<F+HC plots. The degree of macroaggregation showed high correlation coefficients (r ≥ 0.95) with the contents of organic and inorganic components or the hyphal length. Most of these properties were strongly intercorrelated among themselves. The results obtained in this study suggest that organic matter including polysaccharides, active Al, and hyphae play an important role together in soil macro aggregation in the field subjected to double cropping under study. 相似文献
130.
Yuji Goto Muneyuki Hirayama Kazuya Takeda Nobuyuki Tukamoto Osamu Sakata Hiroshi Kaeriyama Masaya Geshi 《Animal Science Journal》2013,84(8):592-599
In this study, we compared the developmental ability of somatic cell nuclear transfer (SCNT) embryos reconstructed with three bovine somatic cells that had been synchronized in G0‐phase (G0‐SCNT group) or early G1‐phase (eG1‐SCNT group). Furthermore, we investigated the production efficiency of cloned offspring for NT embryos derived from these donor cells. The G0‐phase and eG1‐phase cells were synchronized, respectively, using serum starvation and antimitotic reagent treatment combined with shaking of the plate containing the cells (shake‐off method). The fusion rate in the G0‐SCNT groups (64.2 ± 1.8%) was significantly higher than that of eG1‐SCNT groups (39.2 ± 1.9%) (P < 0.05), but the developmental rates to the blastocyst stage of SCNT embryos per fused oocytes were similar for all groups. The overall production efficiency of the clone offspring in eG1‐SCNT groups (12.7%) per recipient cow was higher than that in G0‐SCNT groups (3%) (P < 0.05). The mean birth weight of cloned calves and the average calving score in the G0‐SCNT groups (48.1 ± 3.4 kg and 3.3 ± 0.3, respectively) was significantly higher (P < 0.05) than those of eG1‐SCNT groups (37.2 ± 2.1 kg and 2.3 ± 0.2, respectively). Results of this study indicate that synchronization of donor cells in eG1‐phase using the shake‐off method improved the overall production efficiency of the clone offspring per transferred embryo. 相似文献