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101.
本试验目的是评估肉鸡日粮中添加谷氨酰胺(Gln)和维生素E对其肠道黏膜形态学的作用。试验采取2×3因子(维生素E×Gln添加时间)的完全随机设计,维生素E添加水平为10和500mg/kg,Gln按3种情况向肉鸡开食日粮中的添加:即不添加、从出壳后头7d内添加和头14d内添加。肉鸡生长期日粮处理仅由维生素E两种添加水平组成。试验肉鸡共1500羽,设6个处理,每个处理分5个重复50羽肉鸡。在出壳后第7、14、21和41天,每个重复随机取2羽肉鸡扑杀,取十二指肠、空肠和回肠样本各5cm长,经处理后测定肠道黏膜绒毛高度和隐窝深度,并用方差分析所得数据,用Tukey氏检验按5%的显著水平比较平均值。结果表明,十二指肠发育最快,随后依次为空肠和回肠,出壳后第41天,日粮添加10mg/kg维生素E并再添加1%Gln,对肉鸡肠道黏膜的发育具有促进作用。 相似文献
102.
Summary The role of polyploidy in the evolution of the sweet potato. I. batatas (2n=6x=90), became more clear in 1971 when wild species with 30, 60, and 90 chromosomes were discovered. These species, I. leucantha (2x), I. littoralis (4x) and I. trifida (6x), are the progenitors of the sweet potato (6x), in an autopolyploid series with doubling of the I. leucantha B genome.In the present study the hypothesis of the origin of the sweet potato was confirmed by comparative studies on some plant characters, sexual compatibility, and the behavior of artificial hexaploids produced from I. leucantha (2x) and I. littoralis (4x).Since induced hexaploid I. leucantha exhibits weak growth, a few multivalents are formed at meiosis in the sweet potato, and there are differences in morphological and physiological characteristics between the artificial hexaploids and I. batatas, raw autoploidy seems unlikely, but a balanced or diploidised autoploidy could have been achieved by genic and chromosomal changes in the course of evolution. However, there is still sufficient homology so that meiotic pairing occurs usually between regular partners but also between homoeologous chromosomes in a certain situation. 相似文献
103.
Shinichi Ogiyama Kazunori Sakamoto Hiroyuki Suzuki Shingo Ushio Tetsuo Anzai Kazuyuki Inubushi 《Soil Science and Plant Nutrition》2005,51(6):801-808
An experiment was conducted to examine the accumulation and mobility of heavy metals (Zn and Cu) at different depths in three types of arable soils (Brown Lowland soil, Andosol, and Brown Forest soil) amended with cattle and pig farmyard manures for 5 years. Nitric-perchloric acid digestion was performed for the determination of the total amounts of heavy metals, and 0.1 M hydrochloric acid extraction was performed for the determination of the amounts of soluble heavy metals. Results of the soil analysis indicated that pig farmyard manure application resulted in serious contamination of arable soils with Zn and potentially Cu. Especially, the Brown Forest soil displayed a high ability to accumulate heavy metals on the soil surface. Total-Zn concentration in surface soils was considerably affected by the holding capacity of soluble-Zn traction. Although the Andosol amended with pig farmyard manure showed higher concentrations of heavy metals related to the higher ability of retention on a weight basis, the soil did not contribute to high heavy metal accumulation because of its low bulk density. Heavy metals were easily leached in sandy soils such as Brown Lowland soil, and Cu was potentially stable compared with Zn. We suggest that long-term pig farmyard manure application to the Brown Lowland soil and Andosol with a light soil texture is associated with a higher risk of groundwater pollution than the application to the Brown Forest soil. 相似文献
104.
A. Sorimachi M. Sakai O. Ishitani M. Nishikawa K. Sakamoto 《Water, air, and soil pollution》2001,130(1-4):541-546
In order to obtain information on dry deposition of SO2 onto loess in China, the effects of water vapor and NO2 on SO2 deposition-oxidation processes were investigated in laboratory measurements. The deposition velocities of SO2 onto loess particles were 2.34–7.33 cm s?1, were high in comparison with the other studies. Deposition of SO2 onto the particles was decreased with exposed time and amounts of SO2, but was influenced by adsorption of water vapor onto the particles. On the other hand, oxidation of SO2 physically8 adsorbed was promoted by the coexistence of water vapor and NO2. So, it was indicated that it was possible for water vapor and NO2 in the atmosphere to play an important role in dry deposition for the deposition-oxidation interaction between SO2 and loess particles. 相似文献
105.
R. L. Pfeifle E. M. Beasley N. E. Crabtree C. Fraser J. A. Elbert E. Ducker K. Nagata B. C. Garner K. Sakamoto 《Equine Veterinary Education》2021,33(11):e411-e415
A 27-year-old Arabian pony gelding presented for evaluation of weight loss, intermittent sheath oedema, persistent neutropenia and thrombocytopenia, and acute left hindlimb swelling and gait abnormality. Clinical findings included swelling, heat and sensitivity localised over the left greater trochanter, mild to moderate ventral and sheath oedema, a left hindlimb post-legged gait, and off-loading of weight from the left hindlimb at rest. Initially, neutropenia and thrombocytopenia were confirmed on bloodwork, but neutrophilia and thrombocytopenia persisted as the case progressed. Diagnostic imaging (radiography and percutaneous ultrasonography) of the left hindquarters revealed an aggressive, mixed proliferative and lytic bony lesion of the proximal left femur as well as associated muscle fibre disruption and a soft tissue mass. A percutaneous core biopsy of the lesion led to the diagnosis of osteoblastic osteosarcoma on histopathology. Pain and inflammation associated with the lesion was medically managed in the hospital with mild improvement. Additionally, palliative radiation was performed under general anaesthesia. Unfortunately, before a response to palliative radiation could be assessed, the patient was subjected to euthanasia due to development of acute neurological signs. 相似文献
106.
R Kano Y Sakamoto A Hanahachi H Kamata Y Fukuda K Fujiwara A Hasegawa 《Journal of veterinary diagnostic investigation》2001,13(5):437-439
A 2-month-old cockatiel was evaluated for diarrhea, dyspnea, and death. Histologic examination of lesions in the crop mucosa revealed hyperkeratosis and the presence of blastoconidia and hyphae. Positive immunohistochemical staining of the organisms was achieved with an antibody directed against Candida spp. Polymerase chain reaction amplification of DNA from crop lesion material with internal transcribed spacer 2 (ITS2) primers yielded fragments of approximately 300 bp, which demonstrated 95% DNA homology with the corresponding sequence from a strain of Candida parapsilosis deposited in the GenBank data base. The Candida species in the lesion of the crop mucosa was therefore identified by DNA sequence analysis as C. parapsilosis. 相似文献
107.
Masahiro Takatani Kohei Ikeda Kei Sakamoto Tadashi Okamoto 《Journal of Wood Science》2008,54(1):54-61
One of the important issues relevant to wood/plastic composite molding is the compatibility between hydrophilic wood and hydrophobic
plastic. Polyolefins modified with maleic anhydride, which have been frequently used for wood and polyolefin composites, are
not effective for poly(lactic acid) composites. Because compounds with both hydrophilic and hydrophobic groups are potential
compatibilizers, cellulose esters of several carboxylic acids, RCOO-cellulose (R = CH3, C2H5, C3H7, C4H9, C5H11, C11H23), were synthesized and their effects as compatibilizers of wood/poly(lactic acid) composites (WPLC) were examined in this
study. The mechanical properties of WPLC were improved with a small amount of added cellulose esters, especially cellulose
butyrate or cellulose valerate. The relevant effect of added cellulose esters on the thermal properties of wood/PLA composite
was analyzed by measuring dynamic viscoelasticity.
Part of this report was presented at the 56th Annual Meeting of Japan Wood Research Society, Akita, August 2006 and the 9th
International Conference on Frontiers of Polymers and Advanced Materials, Cracow, Poland, July, 2007 相似文献
108.
Weina Jiang Satoshi Tan Yusuke Hanaki Kazuhiro Irie Hajime Uchida Ryuichi Watanabe Toshiyuki Suzuki Bryan Sakamoto Michiya Kamio Hiroshi Nagai 《Marine drugs》2014,12(12):5788-5800
The toxin-producing cyanobacterium, Moorea producens, is a known causative organism of food poisoning and seaweed dermatitis (also known as “swimmer’s itch”). Two new toxic compounds were isolated and structurally elucidated from an ethyl acetate extract of M. producens collected from Hawaii. Analyses of HR-ESI-MS and NMR spectroscopies, as well as optical rotations and CD spectra indicated two new lyngbyatoxin derivatives, 2-oxo-3(R)-hydroxy-lyngbyatoxin A (1) and 2-oxo-3(R)-hydroxy-13-N-desmethyl-lyngbyatoxin A (2). The cytotoxicity and lethal activities of 1 and 2 were approximately 10- to 150-times less potent than lyngbyatoxin A. Additionally, the binding activities of 1 and 2 possessed 10,000-times lower affinity for the protein kinase Cδ (PKCδ)-C1B peptide when compared to lyngbyatoxin A. These findings suggest that these new lyngbyatoxin derivatives may mediate their acute toxicities through a non-PKC activation pathway. 相似文献
109.
Yoshio Aikawa Iwao Nagano Shunjiro Sakamoto Masaya Nishiyama Satoshi Matsumoto 《Soil Science and Plant Nutrition》2013,59(4):835-842
Scopelophila ligulata (Spruce) Spruce, S. cataractae (Mitt.) Broth., and Mielichhoferia japonica Besch. (Mielichhoferia mielichhoferi (Hook.) Wijk et Marg. var. japonica (Besch.) Wijk et Marg.) are well known “copper mossess” which show peculiar ecological characteristics consisting of a preference for metal-rich soils, lithosols, rocks, etc. as their substrates. The total and water-soluble element contents in the substrates and heavy metal contents in the moss body were analyzed in this study. The results of these chemical analyses were as follows: The iron contents in the moss body and substrate of S. ligulata were higher than those of S. cataractae and M. japonica. On the contrary the copper contents of the former were lower than those of the latter. The pH values of substrate of S. ligulata were lower than those of S. cataractae and M. japonica. The concentrations of water-soluble iron and sulfate in the substrate of S. ligulata were higher than those of S. cataractae and M. japonica. On the contrary, the water-soluble copper concentrations in the substrate of S. ligulata were lower than those of the others. Although in the substrate of S. cataractae the iron content was several times higher than the copper content, in the moss body the copper content was higher than iron content. 相似文献
110.
D L Gutnick P J Dunphy H Sakamoto P G Phillips A F Brodie 《Science (New York, N.Y.)》1967,158(807):1469-1471
Synthetic phylloquinone was resolved into cis and trans isomers by thin-layer chromatography. The two isomers had identical ultraviolet spectra characteristic of vitamin K(1) and were differentiated by nuclear-magnetic-resonance spectroscopy on the basis of the displacement of the peak corresponding to the olefinic methyl group in the naphthoquinone side chain. Studies on the restoration of electron transport coupled to phosphorylation in irradiated preparations of Mycobacterium phlei showed that only the trans isomer was active with substrates linked to nicotinamide-adenine dinucleotide. The purified trans phylloquinone was enzymatically converted to the cis isomer. Under similar conditions, cis vitamin K(1) gave rise to the trans-naphthoquinone. The natural naphthoquinone of M. phlei vitamin MK(9)(II-H) was similarly resolved into cis and trans isomers. 相似文献