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91.
Girdling is widely used for many crops, mainly in order to improve the fruit set, size, and quality and to increase the yield of flower buds. However, girdling may damage trees, and permanent injury can occur if callus bridges are not formed across the ring. We determined the regeneration of vascular bundles and the healing process of wounds caused by surgical treatments. It occurred as follows: necrosis of some cell layers on the edge of the cut, callus formation and dedifferentiation of the parenchyma cells, callus proliferation, contact between callus pads, callus bridge formation, and differentiation into the mature vascular bundle; however, the innermost callus cells remained undifferentiated. At 3 days after treatment (DAT), several phloem parenchyma cell layers showed symptoms of necrosis. At 10 DAT, callus formation started in the phloem tissue below the periderm. Initially, the callus cells were uniform; however, the callus tissue pad was distinguished into 2 layers based on color and firmness. After callus bridge formation, the inner callus differentiated into the mature xylem and the outer callus, into mature phloem. In strangulation, xylem elements were formed from the inner callus pad before callus bridge formation. The callus bridge formed within 6 weeks, 20–25 days, and 14 weeks after girdling, scoring, and strangulation, respectively. 相似文献
92.
Tetsuro Shiraishi Kumiko Okamoto Michio Yoneda Takeshi Sakai Seiji Ohshimo Shizumasa Onoe Akihiko Yamaguchi Michiya Matsuyama 《Fisheries Science》2008,74(5):947-954
The age and growth of chub mackerel Scomber japonicus collected from the East China Sea and the northern waters off Kyushu between June 2000 and June 2001 were determined by observing
the otolith surface after dipping it in xylene. The translucent and opaque zones on the otolith surface were identified, and
the number of translucent zones was counted. Monthly changes in the frequency of fish with translucent zones on the otolith
margin, and in the marginal increments, indicated that the translucent zones were formed between April and June. The seasonal
pattern of annulus formation on the otolith became clear by observing the otoliths of fish with known ages, and the otolith
formation in wild fish was consistent with that of fish with known ages. The mean gonadosomatic index of male and female fish
was high from March to May, and spawning females were observed from mid-March to mid-May. The estimated ages were 1–5 years
for males and 1–6 years for females. The von Bertalanffy growth parameters did not significantly differ between male and female.
The model was obtained as FL
t=406×{1−exp[−0.372×(t+1.68)] 相似文献
93.
Atsushi Mori Kazuhisa Tashiro Kyoko Makita Masahiro Takatani Tadashi Okamoto 《Journal of Wood Science》2005,51(1):33-37
For the purpose of developing a new aqueous emulsion-type adhesive for wood or paper use that does not release formaldehyde or volatile organic solvents, a honeymoon-type acrylic adhesive was examined. An adhesive system consisting of acrylic monomers copolymerized with functional monomers and a cross-linking agent was selected for the purposes of increasing initial adhesive strength and ensuring room-temperature curing. The initial adhesive strength increased by the use of cross-linkers such as dihydrazides and also polymeric methylene diphenyl diisocyanate (pMDI). Thus an adhesive with reasonable to good initial adhesive strength and room-temperature curing was obtained. The effect of pMDI on the initial adhesive strength was not significant and decreased when the amount of acrylamide in a copolymer was high. 相似文献
94.
T Matsuno F Hariguchi T Okamoto 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1991,53(1):13-17
Pamaquine and primaquine, the well known antimalarial 8-aminoquinolines, have not been reported for their anticoccidial activity. A series of battery experiments was conducted to investigate their activity against a laboratory strain of Eimeria tenella, E. necatrix, E. acervulina, E. maxima, or E. brunetti and revealed that both drugs were effective against E. tenella and E. necatrix, but not against the other three species. Pamaquine suppressed the symptoms of E. tenella induced coccidiosis at concentrations above 125 ppm in feed and primaquine controlled the clinical signs as well at levels above 31.2 ppm. The activity against E. necatrix was observed with pamaquine at 250 ppm and with primaquine at levels above 125 ppm. Pamaquine showed a tendency apparently to reduce body weight gain at 125-500 ppm, whereas primaquine showed the same tendency at 500 ppm. In a concomitantly conducted experiment, this adverse effect of pamaquine was averted in its molecular complexes with benzophenone, nitropyrazole, dinitrobenzoic acids and quinoline, and in its salts of sulfate or zinc chloride, and yet these compounds retained the same anticoccidial activity as of pamaquine. This suggests that these compounds had the broadened safety margin. Judging from their susceptibility to these compounds. E. tenella and E. necatrix will have similar metabolic functions to those of blood cell parasitizing protozoa like plasmodia and prioplasma, which are easily suppressed by this class of compound. 相似文献
95.
Y Akihara Y Shimoyama K Kawasako M Komine K Hirayama A Terasawa T Ohmachi K Matsuda M Okamoto H Taniyama 《Reproduction in domestic animals》2007,42(5):495-501
In the present study, 15 canine ovaries without morphological lesions were examined histologically and immunohistochemically by using a large number of proteins including AE1/AE3, cytokeratin7 (CK7), CK13, CK20, vimentin, desmin, alpha smooth muscle actin (alphaSMA), calponin, S100, Neurofilaments, Inhibinalpha, placental alkaline phosphatase (PLAP) and neuron-specific enolase. Ovarian structures observed in this study included surface epithelium (SE), cortical tubules (CT), tunica albuginea (TA), stromal cells (SC), internal endocrine cells (IE), rete ovarii (RO) and fallopian tubes (FT). SE, CT, RO and FT were broadly immunoreactive for desmin. Besides AE1/AE3 and vimentin, desmin was also closely linked to these structures. Rete ovarii forming a reticular structure showed a positive reaction to S100. Surface epithelium was immunoreactive for PLAP at a significantly high level. In conclusion, these results indicate a specific segment of immunoreactivity as well as the broad range of immunoreactivity in canine ovary. The distinct patterns of immunoreactive for various kinds of proteins will play an important role in facilitating their identification and discrimination even in a normal canine ovary with a complex structure. 相似文献
96.
97.
Chuma T Ikeda T Maeda T Niwa H Okamoto K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(9):1027-1029
Cecal contents (16 samples/each flock) of broilers derived from 212 flocks were investigated for colonization of Campylobacter from 1995 to 1999 in the southern part of Japan, and the isolates were tested for antimicrobial susceptibilities. C. jejuni-positive flocks numbered 42 (19.8%) and C. coli-positive ones 26 (12.3%); Campylobacter spp. were recovered from 68 flocks (32.1%) in total. MICs of ampicillin, erythromycin (EM), tetracycline, nalidixic acid (NA), norfloxacin (NFLX), and ofloxacin (OFLX) to these 68 Campylobacter isolates were determined. Quinolone-resistant Campylobacter isolates numbered 22 (32.4%). All the isolates except one were cross-resistant to NA, OFLX, and NFLX. A high frequency of quinolone-resistance was found in both C. jejuni and C. coli, whereas a high level of EM-resistance was found in only C. coli strains. All C. jejuni isolates were sensitive to EM. 相似文献
98.
99.
Soliman M Okamoto S Kitamura H Kushibiki S Kimura K Saito M 《The Japanese journal of veterinary research》2004,52(2):95-99
The responses of plasma cortisol and adrenocorticotropic hormone (ACTH) were examined to intravenous injection of recombinant bovine tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (INF-gamma) in Holstein cows. INF-gamma induced dose-dependent rises in the plasma levels of both cortisol and ACTH, while TNF-alpha induced comparable plasma cortisol responses with much smaller rises in plasma ACTH. The results suggest a direct stimulatory action of TNF-alpha on cortisol secretion from the adrenal gland in cattle. 相似文献
100.