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排序方式: 共有492条查询结果,搜索用时 62 毫秒
101.
Teruo NONOMURA Yoshinori MATSUDA Mikako TAKASUGI Takashi OOTANI Tomoya HASEGAWA Kazutomo MIYAJIMA Tetsuya HATASA Hideyoshi TOYODA 《Journal of General Plant Pathology》2001,67(4):273-280
Using melon seedlings at the cotyledon stage and genetically marked fungi, a system for monitoring pathogenic and nonpathogenic
Fusarium oxysporum was devised in the present study. Protoplasts were prepared from three formae speciales (melonis, radicis-lycopersici and fragariae )of F. oxysporum and transformed with a synthetic gene for green fluorescence protein. Transformants were primarily isolated in the presence
of hygromycin B and then screened by the emission of bright green fluorescence. Roots of melon seedlings were inoculated with
fluorescing microconidia of these fungi, and fungal infection behavior was traced. Using fluorescence microscopy, we directly
observed not only the fungus at the root surface, but also the mycelia elongating in the trachea of roots. Both pathogenic
and nonpathogenic fungi germinated and hyphae elongated superficially on the surface of root. Only pathogenic fungi caused
root necrosis at the inoculation site. Hyphae grew within the stem to induce constriction or cracking of lower hypocotyls,
then causing wilting of the seedlings. Infection behavior of genetically marked pathogenic and nonpathogenic F. oxysporum could be successfully monitored after inoculation of cotyledons of seedlings.
Received 6 June 2001/ Accepted in revised form 3 August 2001 相似文献
102.
A trihaloimidazole derivative (S-377; 1-(4-chlorobutoxymethyl)-2,4,5-trichloroimidazole) caused giant excitatory junctional potentials by a single electrical stimulus to the excitatory nerves. Repetitive discharges were simultaneously induced in the nerve fibres. S-377 also caused repetitive firing in the inhibitory nerve fibres. Permethrin showed quite similar actions on both the junction and nerve fibres. It was supposed that S-377 inhibited the inactivating system of the sodium channel, like pyrethroids. However, S-377 reduced the number of spikes of the permethrin-induced repetitive discharges on the excitatory nerve fibres. These observations suggest that binding sites of S-377 on sodium channels are different from those of pyrethroids. 相似文献
103.
Effect of a single polymorphism in the Japanese quail NK‐lysin gene on antimicrobial activity 下载免费PDF全文
Taichiro Ishige Hiromi Hara Takashi Hirano Tomohiro Kono Kei Hanzawa 《Animal Science Journal》2016,87(1):143-146
NK‐lysins are cationic peptides that play important roles in host protection, and are an important constituent of innate immunity. We identified nine single‐nucleotide polymorphisms (SNPs) in the NK‐lysin open reading frame (ORF) from 32 Japanese quails in six strains: A, B, ND, K, P, and Y. The G to A substitution at nucleotide position 272 in the ORF resulted in a Gly (G) to Asp (D) amino acid substitution (Cj31G and Cj31D alleles). The Cj31D allele was detected in P (frequency 0.76) and Y (frequency 0.03) strains. We compared the antimicrobial activities of four synthetic peptides from the helix 2‐loop‐helix 3 region of avian NK‐lysins against Escherichia coli: Cj31G and Cj31D from quail and Gg29N and Gg29D from chicken. The antimicrobial activities of the four peptides decreased in the following order: Gg29N > Cj31G > Gg29D > Cj31D (P < 0.05). Although there were no differences in the predicted secondary structure of the Cj31G and Cj31D, the net charge of the Cj31G was higher than that of Cj31D. These data indicated that the antimicrobial activity of CjNKL is influenced by net charge, similar to that which has been observed in chicken. © 2015 Japanese Society of Animal Science 相似文献
104.
Influence of weaning age on the villous height and disaccharidase activities in the porcine small intestine 下载免费PDF全文
Takamitsu Tsukahara Ryo Inoue Masako Nakatani Kikuto Fukuta Eriko Kishino Tetsuya Ito Kazunari Ushida 《Animal Science Journal》2016,87(1):67-75
Body weight gain after weaning is correlated with villous height and disaccharidase activity. This evidence suggests that the maintenance of the small intestinal structure and function after weaning is important for the growth of piglets. We demonstrated that the influence of weaning age was obtained by disaccharidase activities and villous height in eight sections of the porcine small intestine. Therefore, we designed three weaning ages (weaned at the ages of 14, 21 or 28 days) and the piglets were slaughtered after 7 or 14 days post‐weaning. The remaining suckling piglets were slaughtered at the age of 1, 7, 14, 21 and 28 days. Four piglets were slaughtered at each event; therefore, 44 piglets were used in this study. Villous height and disaccharidase activities were measured in each section of the small intestine. Early weaning such as that at 14 days had severe influence on villous and disaccharidase activities. In particular, weaning of 14‐day‐olds did not result in maltase activity at least 2 weeks post‐weaning. Accordingly, the weaning age of crossbred piglets is recommended to be at least 21 days or more on the basis of villous height and disaccharidase activity analyses. 相似文献
105.
Norio Kurihara Tetsuya Suzuki Minoru Nakajima 《Pesticide biochemistry and physiology》1980,14(1):41-49
Metabolism experiments with rats showed that significant isotope effects () were associated with the in vivo formation of dichloro and trichlorophenylmercapturic acids from a 1:1 mixture of normal and hexadeuterated lindane. This is evidence that rate-determining dehydrogenation and dehydrochlorination, both of which proceed with significant isotope effects, are essential in the pathway of dichloro- and trichlorophenylmercapturic acid formation from lindane. No significant primary isotope effects were associated () with the formation of monochlorophenylmercapturic acid. This suggests that the 1,2-dechlorination to tetrachlorocyclohexene followed by glutathione conjugation is the probable pathway that produces this metabolite from lindane. 相似文献
106.
Y Kanai H Kawakami M Kanai-Azuma M Kurohmaru H Hirano Y Hayashi 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1992,54(2):297-303
Changes in the intracellular and cell surface localization of Lewis x (Le(x)) determinants in germ cells during fetal development in mice were examined by light and electron microscopy. Light microscopically, in undifferentiated gonads on day 12 post coitum (p.c.), the anti-Le(x) monoclonal antibody (MAb) was specifically bound to the plasma membranes and to the cytoplasmic granule-like structures of germ cells. In the testes on day 13 p.c., most of the germ cells were enclosed within the testicular cords and showed an MAb-positive reaction which was restricted mainly to the cytoplasmic granule-like structures. The reaction on the plasma membranes almost disappeared. On the other hand, the ectopic germ cells still showed a positive reaction on their plasma membranes. In the ovaries on day 13 p.c., the germ cells also exhibited positive reactions both on the plasma membranes and on the granule-like structures. Immunoelectron microscopic observations agreed well with these light microscopic observations in such a way that both the plasma membranes and the "small dense bodies" (SDB) were positive in undifferentiated gonads on day 12 p.c. In the germ cells organized into the testicular cords, the reaction to anti-Le(x) MAb became restricted to the SDB. These results may indicate that such intracellular changes in Le(x) determinants during germ cell differentiation are associated with the enclosure of germ cells within the testicular cords. 相似文献
107.
Effect of negative dietary cation‐anion differences on carcass characteristics and beef tenderness of Japanese Black steers 下载免费PDF全文
Lowering dietary cation‐anion differences (DCAD) can enhance responsiveness to Ca‐homeostatic hormones and increase Ca availability, which might have potential to activate a Ca‐dependent protease, calpain, and to enhance postmortem myofibrillar proteolysis. In this study, we investigated the effects of DCAD manipulation on calpain activity and beef tenderness in Japanese Black cattle which are characterized by their high marbling. Thirty‐six Japanese Black steers were allotted to one of two treatments: (i) control (CON; DCAD +6.09 mEq/100 g of dry matter (DM)) or (ii) negative DCAD (NEGD; DCAD ?8.27 mEq/100 g DM) for 70 days before slaughter. Lowering DCAD decreased DM and energy intake (P < 0.01) even though it did not negatively affect the growth performance or carcass characteristics. In NEGD, urine pH was decreased by acidification caused by the negative DCAD (P < 0.01). Calpain activities tended to be improved in NEGD (P = 0.09), but Warner‐Bratzler shear force values were not affected by treatment. Although calpain activities tended to improve, lowering DCAD to ?8.27 for 70 days before slaughter was insufficient to enhance beef tenderness in Japanese Black steers. 相似文献
108.
Mona Uchida Yuki Matsumiya Masaya Tsuboi Kazuyuki Uchida Takayuki Nakagawa Wataru Fujii Tetsuya Kobayashi Hajime Tsujimoto Aki Ohmi Hirotaka Tomiyasu Tomoki Motegi Shingo Maeda Yasuyuki Momoi Tomohiro Yonezawa 《Veterinary and comparative oncology》2023,21(3):391-400
Histiocytic sarcoma (HS) is a rare neoplasm of macrophages or dendritic cells with a poor prognosis in dogs. As the apoptosis inhibitor of macrophage (AIM) is characteristically expressed in canine macrophages, we hypothesised that AIM is involved in the development or progression of HS in dogs. In this study, AIM expression in the tumour region and serum AIM levels in dogs with HS was assessed. Additionally, the effects of AIM overexpression on HS cell viability were investigated using a HS cell line that was selected from five validated HS cell lines. Immunohistochemistry showed that AIM expression was observed in the cytoplasm of the HS cells. CD36, a candidate AIM receptor, was also observed on the cell membrane of HS cells. When the serum AIM level was detected in 36 dogs with HS and 10 healthy dogs via western blot analysis, the AIM levels in the HS dogs were significantly higher than those in the controls. AIM mRNA expression in the 5 HS cell lines varied but was higher than that in the other tumour-derived lines. Among the five HS cell lines, DH82 originally had lower AIM and the highest CD36 expression. When AIM was overexpressed in DH82, therein cell growth speed and invasion, apoptosis inhibition and phagocytic activity were strongly upregulated. These data suggest that elevated intra-tumour expression of AIM could induce the progression of HS cells in dogs. Moreover, elevated serum AIM levels in dogs with HS could serve as a biomarker of HS. 相似文献
109.
To produce 5-reductase inhibitory compounds, resveratrol was enzymatically oxidized in a horseradish peroxidase (HRP)/H2O2 system. Ethyl acetate extract of the oxidation products showed strong 5-reductase inhibitory activity with 10%–15% organic solvents in the system, whereas without organic solvent little inhibitory activity was exhibited. The optimum pH of enzymatic oxidation for acquisition of the inhibitory activity was 4.5. The inhibitory compounds were isolated and identified as resveratroltrans-dehydrodimer and resveratrolcis-dehydrodimer by comparing with published nuclear magnetic resonance data. The two resveratrol dehydrodimers have stronger inhibitory activity than natural resveratrol dimers and trimers found inShorea species. 相似文献
110.