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排序方式: 共有458条查询结果,搜索用时 15 毫秒
91.
Erwin Shuhei Takemoto Won-Joung Hwang Miyuki Takeuchi Takao Itoh Yuji Imamura 《Journal of Wood Science》2008,54(3):233-241
To further our understanding of wood decay in living light red meranti (Shorea smithiana) trees, microscopic characteristics of the cell and cell wall degradations of S. smithiana wood in the presence of the decay fungi, the identity of the causal fungi, and the decay potential and pattern by an isolated
fungus were investigated. Cell wall degradations, including cell wall thinning, bore holes formation, rounded pit erosion,
and eroded channel opening were clearly observed under light and scanning electron microscopy. In transverse view, many large
voids resulting from a coalition of degraded wood tissue appeared in the decayed canker zone. All these observations suggest
the well-known simultaneous decay pattern caused by white-rot fungi. By phylogenetic analysis based on the sequences of internal
transcribed spacer region of ribosomal DNA, a basidiomycete fungus isolated from the decayed wood was identified as Schizophyllum commune. The degradation caused by this fungus on sound S. smithiana wood in an in situ laboratory decay test was classified as the early stage of simultaneous decay, and showed a similar pattern
to that observed in the wood samples naturally decayed. 相似文献
92.
Effects of β‐carotene‐enriched dry carrots on β‐carotene status and colostral immunoglobulin in β‐carotene‐deficient Japanese Black cows 下载免费PDF全文
Yoshitaka Nishijima Saya Taniguchi Shuntaro Ikeda Kenichi Yoshitani Takashi Hamano Hiroshi Tani Masahiko Fujita Kenji Murakami Keisuke Kogusa Kenji Sato Miki Sugimoto Shinichi Kume 《Animal Science Journal》2017,88(4):653-658
Data from 18 β‐carotene‐deficient Japanese Black cows were collected to clarify the effects of feeding β‐carotene‐enriched dry carrots on β‐carotene status and colostral immunoglobulin (Ig) in cows. Cows were assigned to control or carrot groups from 3 weeks before the expected calving date to parturition, and supplemental β‐carotene from dry carrots was 138 mg/day in the carrot group. Plasma β‐carotene concentrations in the control and carrot groups at parturition were 95 and 120 μg/dL, and feeding dry carrots slightly improved plasma β‐carotene at parturition. Feeding dry carrots increased colostral IgA concentrations in cows and tended to increase colostral IgG1, but colostral IgM, IgG2, β‐carotene and vitamin A were not affected by the treatment. Feeding dry carrots had no effects on plasma IgG1, IgA and IgM concentrations in cows, but plasma IgG1 concentrations decreased rapidly from 3 weeks before the expected calving date to parturition. These results indicate that feeding β‐carotene‐enriched dry carrots is effective to enhance colostral IgA and IgG1 concentrations in β‐carotene‐deficient cows. 相似文献
93.
Shyamal C MAHATA Ryoichi MITSUO Jun-Ya AOKI Hironori KATO Takao ITAKURA 《Fisheries Science》2003,69(3):615-624
ABSTRACT: The cytochrome P450 (CYP) represents a large group of microsomal monooxygenases that catalyze drugs as well as a host of lethal environmental contaminants such as dioxins, leading to either detoxification and excretion from the animal or generation of carcinogenic intermediates. In the present study two forms of cDNA were cloned (Eu MC1 and Eu MC2) for European eel CYP1A genes by polymerase chain reaction (PCR) techniques. The cDNA of Eu MC1 was 3368 bp long coding 521 amino acid residues, and that of Eu MC2 was 2464 bp long coding 517 amino acid residues. Identities of deduced amino acid sequences between Eu MC1 and Japanese eel CYP1A1 and that between Eu MC2 and the second form of Japanese eel CYP1A were 98% and 97%, respectively, showing decisively that Eu MC1 and Eu MC2 are orthologous to Japanese eel CYP1A1 and the second form of CYP1A, respectively. A striking difference between the two eel species was that the Eu MC1 peptide was two amino acid residues longer than that of the Japanese eel CYP1A1. Existence of two loci of CYP1A in Japanese and European eels may suggest that the two forms of CYP1A exist widely among the eel species, because the divergence between the two eel species has been shown to be close to the basal divergence among eels. The identities in CYP1A may help to estimate genetic distance between European and Japanese eels. 相似文献
94.
95.
不同地下水位胡杨蒸腾速率与叶水势的变化分析 总被引:3,自引:0,他引:3
本文研究了不同地下水位胡杨蒸腾速率、叶水势及蒸腾速率的季节变化等水分生理特性,结果表明:地下水位影响胡杨蒸腾作用,同时土壤水分状况也影响蒸腾速率,当地下水位在2.28~2.43 m时,胡杨蒸腾速率变化幅度大,蒸腾速率的日最大值为7.50 mmol.m-2s-1,日均值为4.73 mmol.m-2s-1,对应叶水势的日最低值为-3.55(Mpa)和日均值为-1.94(Mpa);地下水位2.91~3.33 m时,叶水势的日最低值为-2.61(Mpa)和日均值为-1.62(Mpa)。胡杨蒸腾速率季节变化在7月份达到最大值,靠近河岸胡杨蒸腾速率变化较远离河岸胡杨大,表明地下水位低时,胡杨保持较高的水势就能从环境中吸收到水分来满足其正常生长。 相似文献
96.
Kobayashi Takao 《Journal of pest science》1970,43(10):159
Ohne Zusammenfassung 相似文献
97.
Hirano M Watanabe K Murakami M Kano R Yanai T Yamazoe K Fukata T Kudo T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(3):283-284
We excised surgically a feline granulomatous lesion and performed histopathological, mycological and molecular examinations. As a result, it was diagnosed as sporotrichosis, which was the second recorded case of a cat so afflicted in Japan. After the operation, we recognized another nodule on the lymph node. Histopathological examination was therefore performed, but no fungi were detected. To prevent recurrence, the cat was administered a antimycotic drug, itraconazole. As a result, no recurrence was found. Excision of the lesion is the treatment of choice for feline sporotrichosis. 相似文献
98.
Kuwamura M Ide M Yamate J Shiraishi Y Kotani T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(10):1117-1119
A 4-year-old male Shiba dog initially presented with pain of an undetermined origin and hypersensitivity to touch. Seven days later, the dog developed ataxia, hind-leg weakness and knuckling. The dog died on 20 days after presentation. Postmortem examination revealed a mass in the body of thoracic vertebra. Histopathologically, the mass consisted of granulomatous inflammation, including fungal organisms that were immunohistochemically positive for Candida albicans. Similar granulomatous lesions were observed in the systemic lymph nodes, kidneys, pancreas, spleen, prostate gland, thyroid glands and heart. This case was diagnosed as systemic candidiasis with spondylitis. 相似文献
99.
Qian W Miki D Zhang H Liu Y Zhang X Tang K Kan Y La H Li X Li S Zhu X Shi X Zhang K Pontes O Chen X Liu R Gong Z Zhu JK 《Science (New York, N.Y.)》2012,336(6087):1445-1448
Active DNA demethylation is an important part of epigenetic regulation in plants and animals. How active DNA demethylation is regulated and its relationship with histone modification patterns are unclear. Here, we report the discovery of IDM1, a regulator of DNA demethylation in Arabidopsis. IDM1 is required for preventing DNA hypermethylation of highly homologous multicopy genes and other repetitive sequences that are normally targeted for active DNA demethylation by Repressor of Silencing 1 and related 5-methylcytosine DNA glycosylases. IDM1 binds methylated DNA at chromatin sites lacking histone H3K4 di- or trimethylation and acetylates H3 to create a chromatin environment permissible for 5-methylcytosine DNA glycosylases to function. Our study reveals how some genes are indicated by multiple epigenetic marks for active DNA demethylation and protection from silencing. 相似文献
100.
Shizen Ohnishi Noriyuki Miyake Toru Takeuchi Fumiko Kousaka Satoshi Hiura Osamu Kanehira Miki Saito Takashi Sayama Ayako Higashi Masao Ishimoto Yoshinori Tanaka Shohei Fujita 《Breeding Science》2012,61(5):618-624
Soybean dwarf virus (SbDV) causes serious dwarfing, yellowing and sterility in soybean (Glycine max). The soybean cv. Adams is tolerant to SbDV infection in the field and exhibits antibiosis to foxglove aphid (Aulacorthum solani), which transmits SbDV. This antibiosis (termed “aphid resistance”) is required for tolerance to SbDV in the field in segregated progenies of Adams. A major quantitative trait locus, Raso1, is reported for foxglove aphid resistance. Our objectives were to fine map Raso1 and to reveal whether Raso1 alone is sufficient to confer both aphid resistance and SbDV tolerance. We introduced Raso1 into cv. Toyomusume by backcrossing and investigated the degree of aphid antibiosis to foxglove aphid and the degree of tolerance to SbDV in the field. All Raso1-introduced backcross lines showed aphid resistance. Interestingly, only one Raso1-introduced backcross line (TM-1386) showed tolerance to SbDV in the field. The results demonstrated Raso1 alone is sufficient to confer aphid resistance but insufficient for SbDV tolerance. Tolerance to SbDV was indicated to require additional gene(s) to Raso1. Additionally, Raso1 was mapped to a 63-kb interval on chromosome 3 of the Williams 82 sequence assembly (Glyma1). This interval includes a nucleotide-binding site–leucine-rich repeat encoding gene and two other genes in the Williams 82 soybean genome sequence. 相似文献