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141.
Hirata T Hoshina T Sasaki S Sasaki O Osawa T 《The Journal of reproduction and development》2007,53(2):171-177
We conducted a progesterone-based timed AI protocol after follicular fluid aspiration using the ovum pick-up (OPU) technique to examine its applicability to the suckled beef cow. A total of 19 beef cows were randomly allocated to one of the following three groups based on the number of days postpartum: 13 to 60 days (Group A: suckled; early postpartum period, n=9), 61 to 150 days (Group B: suckled; mid postpartum period, n=6), or 151 to 281 days (Group C: non-suckled; prolonged open period, n=4) postpartum. These cows were treated with follicular fluid aspiration and insertion of a progesterone-releasing intravaginal device (PRID) on day 0. The PRID was removed and 500 microg of cloprostenol was intramuscularly administered on day 7. A dose (100 microg) of fertirelin acetate was injected intramuscularly 48 hours later, and this was followed by a timed AI (TAI) after another 18 hours (day 10). Serum samples were taken on days 0, 7, 9, 10, 12, 17, 24 and 31 for determination of the estradiol-17beta (E(2)) and progesterone concentrations. Pregnancy diagnosis was made by rectal palpation approximately 60 days after TAI. There was no significant difference in the peripheral E(2) concentrations among the three groups during the period of the hormonal treatment. The average progesterone concentrations in Group A on day 17 were significantly higher than those in Group B and exceeded 1.0 ng/ml on day 17 and thereafter. There was no significant difference in the numbers of collected immature oocytes among the three groups. The pregnancy rates in Groups A, B, and C were 77.8% (7/9), 83.3% (5/6) and 50.0% (2/4), respectively. In conclusion, this timed AI protocol is applicable to suckled beef cows within the period of 60 days postpartum. 相似文献
142.
Yamazaki E Murakami K Kurita O 《Plant foods for human nutrition (Dordrecht, Netherlands)》2005,60(1):17-23
Dietary fibers were prepared as alkali- and acid-insoluble fractions with chemical phosphorylation from Tossa jute (Corchorus olitorius), defatted soybean (Glycine max), and Shiitake (Lentinula edodes). The dietary fiber fractions treated with alkaline solution containing sodium metaphosphate had the lower protein content and higher total dietary fiber content than those of the preparations without phosphorylation. Alkaline extraction followed by phosphorylation led to a 1.5-fold increase in the water holding capacity of dietary fiber compared with no phosphorylation, whereas the binding capacity to bile acids of dietary fiber was almost the same. The alkali- and acid-insoluble extraction with phosphorylation provided an efficient preparation of water-insoluble dietary fiber with high-water holding capacity from various food sources. 相似文献
143.
Yuuto KAWASHIMA Ayako FUJIMOTO Morihiro SAITO Osamu MIKAMI Yoshiharu ISHIKAWA Koichi KADOTA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(6):968
The histology and immunohistochemistry of pleomorphic and conventional epithelioid mesotheliomas were examined. The former was detected in two young calves aged 2 and 4 months and was characterized by pleomorphic and atypical cells with decreased expression of cytokeratin 7 (CK7). In contrast, the latter was found in a 31-month-old heifer, consisting of tumor cells uniform in size and shape with CK7 expression in nearly all cells. Production of collagen by tumor cells was demonstrated in both histological types, and was considered to be characteristic of bovine epithelioid mesothelioma. Pleomorphic mesothelioma is far more pleomorphic and mitotically active than conventional mesothelioma, and its normal counterpart may be immature mesothelial cells with high proliferation potential, which exist in fetal life and early calfhood. 相似文献
144.
Shuichi Ishizawa Tatsuhiko Suzuki Tomonori Koda Osamu Sato 《Soil Science and Plant Nutrition》2013,59(1):129-138
The nature of soil is modified differently depending upon the artificial condition such as its utilization or management. It is therefore expected that the microbiological characteristic of soil is changed also. Greaves1) and Williams2) reported that the reclamation of virgin soil brought about a change of bacterial count. Suzuki et al3) observed that the kind of fungi differed between a virgin and a cultivated soil and that the vegetative mycelium was numerous in the former than in the latter. On the other hand, according to W aksman and Starkey4), the bacterial count differed depending upon the fertility of soil. Singh5) reported also that the number of fungi and actinomycetes was higher in a fertile than in an infertile soil. Lochhead6), and Lochhead and Chasen studied the bacterial flora of a fertile (long-continued application of manure) and an infertile (no fertilizer for many years) soil and found that a certain difference could be observed when morphological, physiological and nutritional classification are tried. 相似文献
145.
Shuichi Ishizawa Tatsuhiko Suzuki Osamu Sato Hirozo Toyoda 《Soil Science and Plant Nutrition》2013,59(1):85-94
Introduction Many previous investigations, beginning with the observations of Hiltner19, have established the fact that soil in the rhizosphere contains a higher quantity of microorganisms than soil which is not within the influence of the plant root. It has been shown also that the balance between certain physiological groups4,21,43,45, as well as that between morphological types of bacteria or fungi30,50 is changed in the rhizosphere. In addition, Canadian investigators23,34,62) have reported a change in the balance of certain nutritional groups of soil bacteria in the rhizosphere. Two excellent reviews6,22) covering these papers have recently appeared. Since then a number of papers2,7,9,11,13,15-18,25,26,33,36,38-40,48,54,57-60,63) concerning various aspects of the microbial population of the rhizosphere have been published. 相似文献
146.
Methods for estimating Pg content in P type humic acid and for calculating Δlog K of its Pb fraction
Osamu Sato 《Soil Science and Plant Nutrition》2013,59(4):343-351
Based on the assumption that P type humic acid is composed of green fraction (Pg) and brown fraction (Pb),. methods for estimating Pg content and calculatlng Δlog K of Pb by analyzing the absorption curve of P type humic acid were presented. A green fraction of P type humic acid obtained from an alpine meadow soil by gel filtration was used as the Pg standard (λmax 450, 575, and 615 nm, E 1% 290, 126, and 168). Alkaline solutions of standard Pg obeyed the Beer-Lambert law within the concentration range of 1.6 to 31 ppm. To verify the methods, Pg content in the mixed solutions of Pg and A, B, or Rp type humic acid was estimated. It was found that the recovery of Pg would be 95±14 (2S) per cent with a probability of 0.99. Also, the calculation of Δlog K of humic acid in the mixed solutions gave satisfactory results. It was distinctly shown that the shape of absorption spectra of P type humic acid did not only depend on Pg content, but also on Δlog K of Pb. 相似文献
147.
Recent studies have shown that the incorporation of ammonium nitrogen into amino acids in the leaves is strictly dependent on light (1-4). It is speculated that the effect of light on ammonium assimilation may be through the synthesis of the precursors of amino acids, or by the supply of the energy required for amination and amidation with organic acids. In the Vicia faba chloroplasts Givan et al. (1) exhibited that the synthesis of glutamic acid from a-ketoglutarate was linked with the generation of reduced pyridin nucleotide by photosynthetic electron transport. Mitchell and Stocking (2) suggested the direct coupling of glutamine formation with photophosphorylation in the pea chloroplasts. On the other hand. the processes of nitrate assimilation are more indebted to light than those of ammonium assimilation, because the former ones involve the reduction of nitrate to ammonium which is believed to be light-dependent (5). Canvin and Atkins (6). and Atkins and Canvin (7) reported that the incorporation of 15N-labeled ammonium and nitrate into amino acid fractiom was depressed by the dark treatment and by photosystem inhibitors; 3-(3′,4′-dichlrophenyl)-1-1-dimethylurea (DCMU) and carbonyl-cyanide-m-chlorophenyl-hydrazone(CCCP). 相似文献
148.
Chiaki Sano Osamu Ito Tadakatsu Yoneyama Kikuo Kumazawa 《Soil Science and Plant Nutrition》2013,59(4):581-586
In the investigation of nitrogen metabolism in plants, it is important to deal with proteins, which are the end-products of nitrogen metabolism. 相似文献
149.
Abstract One of the authors analyzed the brown spot symptoms developed on plant leaves caused by nutritional disorders using an X-ray Micro-Analyser (Sasaki et al. 1980). The use of an X-ray Fluorescence Element Mapping Spectrometer (XEMS) revealed that external and internal stresses such as X-ray irradiation and manganese excess induced the transport of manganese, and excess of manganese concentration as cationic Mn2+ was related to the formation of the abnormal brown spots (Watanabe and Kobayashi 1986; Watanabe et al. 1988). Since, the mechanism of the transport of manganese remains to be elucidated the analysis of the chemical state of manganese in plant is important. Since the valency of manganese readily changes depending on the redox potential, non-destructiye analysis may be effective. In fact, few studies have been carried out on the non-destructive determination of the manganese state in plant tissues. We studied the state of manganese in rice leaf in performing Extended X-ray Absorption Fine Structure (EXAFS) and X-ray Absorption Near Edge Structure (XANES) analyses by X-ray Absorption Spectrometry with syncrotron radiation as the analytical source. X-ray absorption spectrometry provides structural information about the local surroundings of a metal ion, the binding configuration, etc. The concept and method of analysis were reviewed in detail by Teo (1981). The advantage of these methods over the previous methods is reported and the state and transport of manganese in leaf are discussed. 相似文献
150.
Katsuyuki Katayama Osamu Ito Theertham Pradyumna Rao 《Soil Science and Plant Nutrition》2013,59(3):477-480
Improved varieties of pigeonpea (Cajanus cajan L. Millsp.) still retain some growth characteristics of perennial types of wild species such as slow seedling growth and rato on ability which are considered to be major yield-restricting characteristics when the growth period is shortened. Studies on the physiological background of slow initial growth may help improve the potential productivity of short-duration pigeonpea. It was found that the low seedling vigor of pigeonpea could be ascribed to the small seed size (Narayanan et al. 1981; Brakke and Gardner 1987), low rate of photosynthetic CO2 fixation (Rawson and Constable 1981), and low rates of metabolic processes (Huber and Hanson 1992; Ito et al. 1996). However, few authors have related the slow growth to the retention of current photosynthates and leaf respiration during the night. In contrast, seedling growth of cowpea (Vigna sinensis Endl.) was reported to be vigorous (Brakke and Gardner 1987). The objectives of this study were to characterize the initial growth of pigeonpea in comparison with cowpea. Two experiments were carried out, one dealing with growth analysis and the other with O2 uptake of leaf and retention of current photosynthates during the night. 相似文献