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111.
Saeid Moharramipour Kazuyoshi Takeda Kazuhiro Sato Hideya Yoshida Hisaaki Tsumuki 《Euphytica》1999,106(2):181-185
The inheritance of gramine indole alkaloid was studied in F1 and F2 generations derived from crosses between wild ( Hordeum
vulgare subsp. spontaneum) and cultivated ( H. vulgare subsp. vulgare) barley at adult stage in the field. The means of gramine
content were very low in F1s and F2s in April and May. The ratio of progeny containing gramine to those without gramine (near
zero or undetectable) fit a mono-genic or di-genic model in F2 generation. However, the content of gramine might be controlled
by minor genes in the gramine-containing plants. The direction of dominance was toward lower gramine content. The averages
of dominance ( h/d) in F1 and F2 ranged from partial to complete. Broad-sense heritabilities were high (0.70 to 0.77). The
usefulness of hybrids for breeding aphid resistance and possibility increasing palatability of grazing pasture for sheep and
cattle is discussed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
112.
Y Kuroda M Yoshida T Shibahara T Matsui T Nakane H Hara Y Inoshima H Sentsui 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1999,61(7):749-753
A disease characterized by papules, nodules, vesicles and, rarely, pustules and ulcers on teats was seen among cattle on a farm in Chiba Prefecture, Japan. A virus was isolated by inoculation of fetal bovine lung cell cultures from a vesicle on a teat of an infected cow. The virus was subsequently passaged in fetal bovine lung and muscle cells in which it produced complete cytopathic changes. The virus was identified by physicochemical examinations and electromicroscopic observation as a parapoxvirus. A seroepidemiological survey was performed on antibody to the isolated virus by the agar gel immunodiffusion test. The isolated virus formed a precipitation line which cross reacted with other parapoxviruses isolated previously in Japan. The positive rate was more than 50% among cattle in the Kanto district. The positive rate increased with age. It was suggested that parapoxvirus infection might have already been prevalent among cattle in Japan. 相似文献
113.
Hosoda Naohiko Kurokawa Yoichi Sako Yoshihiko Nagasaki Keizo Yoshida Takashi Hiroishi Shingo 《Fisheries Science》2011,77(4):665-670
ORF69 in the cyanophage infecting Microcystis aeruginosa, Ma-LMM01, shows homology to the family 19 chitinases where the catalytic domain has structural similarity to lysozyme. Chitinases
hydrolyze chitin, a β-1, 4-linked monopolymer of N-acetylglucosamine (GlcNAc); whereas lysozymes hydrolyzes peptidoglycan, alternating β-1, 4-linked copolymers of N-acetylmuramic acid (MurNAc) and GlcNAc. Using amino acid sequence comparison to ORF69, the putative sugar binding residues, Gln162
and Lys165, from the barley chitinase (the model enzyme for the family 19 chitinases) corresponding to subsites −4 and −3
were found to be replaced with Gly209 and Ile213, respectively, in ORF69. To analyze their contribution to substrate binding
affinity, ORF69 was cloned into Escherichia coli; and two mutant proteins G209Q and I213K were prepared using site-directed mutagenesis. The wild-type gene product (gp69)
showed both lysozyme and chitinase activities. In contrast, the I213K mutant showed a decrease (70%) in lysozyme activity
and a significant increase (50%) in chitinase activity; whereas, the G209Q mutant almost completely abolished both enzyme
activities. The data suggest the Ile213 residue is involved in recognizing the substrate MurNAc; and Gly209 has significant
contribution in chitinase and lysozyme activities for the wild-type gp69. 相似文献
114.
Issei Nishiki Mikiko Furukawa Sho Matui Toshiaki Itami Toshihiro Nakai Terutoyo Yoshida 《Fisheries Science》2011,77(3):367-373
In Japan, Lactococcus garvieae infection has been the main fish disease in aquaculture. Although commercial oral and injectable vaccines have been used
to prevent L. garvieae infection in Japan, L. garvieae has been isolated not only from unvaccinated fish but also from vaccinated fish in which immunity induced by vaccination
had diminished. In order to obtain epidemiological information on this fish pathogen, we conducted biased sinusoidal field
gel electrophoresis (BSFGE) pattern analysis and phage typing of L. garvieae isolates (n = 427) from fish in Japan. These isolates were obtained from 13 different fish species between 1980 and 2007. In the BSFGE
analysis, L. garvieae isolates were classified into 17 groups (S1–S17) based on the SmaI digestion patterns and into four groups (A1–A4) based on the ApaI digestion patterns. Phage typing revealed five different phage susceptibility profiles (A–E) in L. garvieae isolates. Since 2005, comparisons of the results of phage typing and BSFGE have indicated the presence of a novel genotype
(S16/A4) with phage type E. All the strains belonging to this type showed lincomycin sensitivity. 相似文献
115.
We investigated effects of silvicultural treatments (planting and subsequent treatments) on understory structure and plant
species diversity in managed Picea glehnii plantations (21–26 years old) in northern Japan. We evaluated the importance of each treatment (machinery site preparation,
planting, weeding, and thinning) in 19 plantations, with considerable variation among treatments overall. The understory had
98 vascular plant species; the most dominant species was a dwarf bamboo Sasa senanensis, followed by tree species Abies sachalinensis and Betula ermanii. Multiple regression analyses showed that thinning negatively influenced plant species diversity. Planting density showed
a strong positive correlation with density of seedlings (height <20 cm), but few independent variables were correlated with
density of saplings (height ≥20 cm and diameter at breast height <1 cm). The negative effect of thinning and the positive
effect of planting density seem to be related to the existence or reinitiation of dense cover of Sasa senanensis. We present possible mechanisms of response to treatments to generalize the results. We then suggest ways to improve current
treatments to meet the goals of wood production and biodiversity conservation in the region. 相似文献
116.
117.
Inwoo Bae Kiyoshi Osatomi Asami Yoshida Atsuko Yamaguchi Katsuyasu Tachibana Tatsuya Oda Kenji Hara 《Fisheries Science》2009,75(3):765-770
A translucent collagen gel was formed from a transparent acidic solution of red stingray collagen by adjusting to physiological
ionic strength and pH in phosphate buffer and then incubating at 25–37°C. During fibril formation from red stingray collagen,
the turbidity increased when the NaCl concentration was increased at constant pH and the rate of fibril formation was accelerated
by higher pH or lower NaCl concentration. The T
m of red stingray collagen fibrillar gel was estimated as 44.3 ± 3.5°C, which was higher than that of the collagen solution,
33.2°C. In addition, red stingray collagen gel maintained its shape without melting and was suitable for culture of mouse
stromal cells at 37°C. 相似文献
118.
Muh Ali Arsyad Takashi Akazawa Chie Nozaki Makoto Yoshida Kenichi Oyama Tatsuo Mukai Masahiro Ogawa 《Fish physiology and biochemistry》2018,44(5):1299-1308
Olive leaf is known to have the high polyphenol content of 6–9% in dry weight. We investigated the effects of olive leaf powder (OLP) supplemented to fish feed on muscle protein of red sea bream (Pagrus major). Fish reared with feed containing 8% OLP for 40 days had 1.4 times higher myofibril content and 2.2 times higher acid-soluble collagen content than fish reared with control feed for the same period. On the other hand, sarcoplasmic protein content and collagenase activity of the muscle were almost the same between the control fish and OLP-diet fish. Microstructure observation of fish muscle showed that OLP-diet fish has more rigid endomysium structure than that of the control-diet fish. Since collagen fiber in endomysium is responsible for the texture of the muscle, feeding OLP to aquaculture fish will lead to a harder muscle texture. The present study suggests that OLP is a useful feed additive to enhance the texture of aquaculture red sea bream muscle through strengthening of the collagen structure in the muscle. 相似文献
119.