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61.
Cortical microtubules (MTs) in differentiating compression wood tracheids of Taxus cuspidata stems were visualized by confocal laser microscopy. They were oriented obliquely at an angle of about 45° to the tracheid axis during formation of the secondary wall. Artificial inclination altered the pattern of alignment of MTs. Banding MTs were helically oriented late during the formation of the secondary walls. These results indicate that MTs might control the orientation and localized deposition of cellulose microfibrils in the secondary walls of compression wood tracheids.Part of this report was presented at the 46th annual meeting of the Japan Wood Research Society, Kumamoto, April 1996 相似文献
62.
Toru Kobayashi Ryo Ishibashi Shinji Yamamoto Satoshi Otani Koichi Ueno Osamu Murata 《Aquaculture Research》2011,42(2):230-239
The timing of primordial germ‐cell (PGC) migration with regard to the gonadal anlagen, gonad formation and sex differentiation was examined histologically in the chub mackerel (Scomber japonicus) at 5–190 days post hatching (dph). At 5 dph, PGCs appeared on the peritoneal epithelium surface or in the mesentery, on the dorsal side of the abdominal cavity. By 10 dph, stromal cells around the PGCs proliferated. The gonadal primordium was formed by 15 dph. The gonadosomatic index was 0.01% at 30 dph and increased thereafter (0.32% in females and 0.04% in males at 160 dph). Ovarian differentiation occurred at 30–40 dph, indicated by ovarian cavity formation (elongation and fusion of the upper and lower ovarian edges). Meiosis was subsequently initiated. A few meiotic oocytes surrounded the cavity at 50 dph; most were in the perinucleolus stage at 60 dph and attained a diameter of 60–70 μm at 190 dph. Testicular differentiation occurred at 30 dph, indicated by the formation of the sperm duct primordium. Spermatogonia gradually proliferated, developing into spermatocytes at the chromatin–nucleolus stage (after 90 dph) and subsequently into spermatids and spermatozoa (160 dph). These data could aid the development of seeding and cell‐engineering technologies for scombrid fish. 相似文献
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64.
Ryo TAKEUCHI Satoshi TAKAGI Kenji HOSOYA Hiroshi OHTA Takaharu ITAMI Masahiro OKUMURA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(11):1740
Canine gastroesophageal intussusception (GEI) is a rare and life-threatening condition that requires prompt diagnosis and treatment. A 19-day-old Siberian Husky with a 4-day history of regurgitation was diagnosed with GEI based on the findings of computed tomography (CT) performed without anesthesia. Endoscopic reduction of intussusception was impossible; thus, surgical reduction by traction of the duodenum was performed. CT revealed improvement of megaesophagus 82 days postoperatively. Eleven months postoperatively, fluoroscopy showed recovery to nearly normal esophageal motility. Two years postoperatively, no clinical signs were reported. CT is useful to diagnose GEI in neonate puppies with poor abdominal fat and to assess the gastric edema and the anatomical association of stomach with other organs. Fluoroscopy is helpful for evaluating postoperative esophageal motility. 相似文献
65.
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
66.
67.
Yoshihiro Katayama Yoko Mashino Nobuyuki Nishikubo Kaori Yoshitomi Ryo Funada Shinya Kajita 《Journal of Wood Science》2002,48(6):457-466
We have investigated the spatial regulation of the accumulation of enzymes involved in the biosynthesis of shikimate and lignin during differentiation of primary xylem from the apical meristem via procambium in hybrid aspen (Populus sieboldii x Populus grandidentata). Immuohistochemical staining revealed that, in the top part of shoots, lignification began in a single or just a few adjacent vessel elements and subsequently spread to neighboring cells. The spatial localization of 3-deoxy-D-arabino-heptulosonate 7-phosphate synthase (DAHPS), which is one of the key enzymes in the shikimate pathway, was tightly correlated with the cell-specific deposition of lignin in the primary xylem. We also found that the spatial localization of enzymes in the general phenylpropanoid pathway and in the lignin-specific pathway was closely associated with the cell-specific deposition of lignin and the accumulation of DAHPS. Our data suggest that enzymes that act in the shikimate, general phenylpropanoid, and lignin-specific pathways are initially produced and function coordinately in a single or a few adjacent elements at the start of primary xylem development. 相似文献
68.
Mariko Shoji Hidenori Sato Remi Nakagawa Ryo Funada Takafumi Kubo Shinjiro Ogita 《Journal of Forest Research》2006,11(6):449-453
The effect of an osmoticum, polyethylene glycol (PEG), on somatic embryo production was examined using embryogenic cells of
Pinus densiflora. In the basal medium containing 30 μM abscisic acid and 6% maltose, the quality of the embryos formed was poor even though
somatic embryos were produced. The addition of PEG with molecular weight of 4000 or 8000 significantly enhanced the development
of both the quality and quantity of somatic embryos. Furthermore, higher levels of a constant osmotic pressure with PEG 8000
in a range from about 300 to 450 mmol/kg could remarkably enhance the morphogenesis of somatic embryos and their number of
embryos produced. A higher stable osmotic pressure with an appropriate molecular weight of PEG is a key factor for the production
of good quality somatic embryos in P. densiflora. 相似文献
69.
It is generally believed that forests are perceived differently according to the cultural background of the visitor. Different
cultural groups tend to have diverse perceptions of tree species, landscapes, or gardens. In this research project, we conducted
interviews of German and Japanese groups (each group consisting of three or more people), to identify their perspectives in
exploring the theme of “cut” and “dead” wood. For this purpose, we interviewed 20 groups from each cultural background (40
data sets in total). Each group was asked to categorize 36 pictures chosen from photographic contests. The results were examined
with PCA and cluster analysis. The quantified results of the two national groups highlighted the dichotomy of the cut and
dead wood relationship. The method and materials used gave robust results. Differences between the two groups were identified
by their perceptions of cut and dead wood. The results are insightful from a methodological and political rationale. First,
new insights were gained by adopting group-based interviews using pictures from photographic contests. Research about public
perceptions in forest science is often dominated by a focus on verbal inquiry. This study explored similar questions, using
visual materials. The interviews consisted of visual materials to overcome bias in languages or the question order. Second,
the results indicated the influence of “close-to-nature forestry” policy on public perceptions. While German society has a
wide practice of leaving dead wood in forests based on their close-to-nature forestry policy, there is no equivalent Japanese
concept. Although Japan and Germany both face pressures for economic restructuring and public participation, the difference
in public perception of forestry can lead to a difference in acceptance for the same policy. If such differences are to exist,
we can observe that the legitimacy of forestry in the two countries is reconstructed in different ways. 相似文献
70.
Takahama U Tanaka M Oniki T Hirota S Yamauchi R 《Journal of agricultural and food chemistry》2007,55(10):4169-4176
The objective of the present study was to elucidate how chlorogenic acid in coffee was transformed under acidic conditions simulating the mixture of saliva and gastric juice. When coffee was incubated in acidified saliva that contained nitrite and SCN-, in addition to nitric oxide (NO), four major components were detected. Two of the four components (components 3 and 4) were generated when chlorogenic acid was incubated in acidified saliva and when incubated in an acidic buffer solution in the presence of both nitrite and SCN-. By the incubation of chlorogenic acid in acidic nitrite in the absence of SCN-, components 3 and 4 were not formed but the quinone of chlorogenic acid and nitrated chlorogenic acid were formed. The result indicates that SCN- was indispensable for nitrous acid induced formation of components 3 and 4. Component 4 was isolated and its structure was determined to be (E)-5'-(3-(7-hydroxy-2-oxobenzo[d] [1,3]oxathiol-4-yl)acryloyloxy)quinic acid. Component 3, which was suggested to be 2-thiocyanatochlorogenic acid, seemed to be formed by the reaction between SCN- and the quinone of chlorogenic acid. As it has been reported that the quinone of chlorogenic acid can react with thiols and can decompose producing H2O2, the formation of component 4 can reduce the toxic effects of the quinone of chlorogenic acid. 相似文献