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71.
Tran Thi Thu Hoai Hiroaki Matsusaka Yoshiko Toyosawa Tran Danh Suu Hikaru Satoh Toshihiro Kumamaru 《Breeding Science》2014,64(2):142-148
Amylose content is one of the most important factors influencing the physical and chemical properties of starch in rice. Analysis of 352 Vietnamese rice cultivars revealed a wide range of variation in apparent amylose content and the expression level of granule-bound starch synthase. On the basis of single-nucleotide polymorphisms (SNP) at the splicing donor site of the first intron and in the coding region of the granule-bound starch synthase I gene, Waxy gene, alleles can be classified into seven groups that reflect differences in apparent amylose content. The very low and low apparent amylose content levels were tightly associated with a G to T in the first intron whereas intermediate and high amylose was associated with a T genotype at SNP in exon 10. The correlation between the combination of T genotype at SNP in the first intron, C in exon 6, or C in exon 10 was predominant among low amylose rice varieties. Our analysis confirmed the existence of Wxop allele in Vietnamese rice germplasm. The results of this study suggest that the low amylose properties of Vietnamese local rice germplasm are attributable to spontaneous mutations at exons, and not at the splicing donor site. 相似文献
72.
73.
Comparisons among MRI signs,apparent diffusion coefficient,and fractional anisotropy in dogs with a solitary intracranial meningioma or histiocytic sarcoma 下载免费PDF全文
Masae Wada Daisuke Hasegawa Yuji Hamamoto Yoshihiko Yu Aki Fujiwara‐Igarashi Michio Fujita 《Veterinary radiology & ultrasound》2017,58(4):422-432
Although MRI has become widely used in small animal practice, little is known about the validity of advanced MRI techniques such as diffusion‐weighted imaging and diffusion tensor imaging. The aim of this retrospective analytical observational study was to investigate the characteristics of diffusion parameters, that is the apparent diffusion coefficient and fractional anisotropy, in dogs with a solitary intracranial meningioma or histiocytic sarcoma. Dogs were included based on the performance of diffusion MRI and histological confirmation. Statistical analyses were performed to compare apparent diffusion coefficient and fractional anisotropy for the two types of tumor in the intra‐ and peritumoral regions. Eleven cases with meningioma and six with histiocytic sarcoma satisfied the inclusion criteria. Significant differences in apparent diffusion coefficient value (× 10?3 mm2/s) between meningioma vs. histiocytic sarcoma were recognized in intratumoral small (1.07 vs. 0.76) and large (1.04 vs. 0.77) regions of interest, in the peritumoral margin (0.93 vs. 1.08), and in the T2 high region (1.21 vs. 1.41). Significant differences in fractional anisotropy values were found in the peritumoral margin (0.29 vs. 0.24) and the T2 high region (0.24 vs. 0.17). The current study identified differences in measurements of apparent diffusion coefficient and fractional anisotropy for meningioma and histiocytic sarcoma in a small sample of dogs. In addition, we observed that all cases of intracranial histiocytic sarcoma showed leptomeningeal enhancement and/or mass formation invading into the sulci in the contrast study. Future studies are needed to determine the sensitivity of these imaging characteristics for differentiating between these tumor types. 相似文献
74.
Kei Nakagawa Shin-Ichiro Wada Ryoma Kitamura Ronny Berndtsson 《Communications in Soil Science and Plant Analysis》2017,48(21):2594-2600
Groundwater pollution by nitrate from agricultural fields is a worldwide problem. To improve the understanding of nitrate transport processes through volcanic ash soils overlying groundwater aquifers, salt sorption experiments were performed. Salt sorption is the process that involves the simultaneous use of cation and anion adsorption mechanisms without changing the pH. Prepared six different concentrations of potassium chloride (KCl) solutions were mixed with soil samples. Anion and cation contents of the liquid and solid phases were determined. Experiments were performed in triplicate of six kinds of KCl solutions for three types of soils. Thus, total 54 of samples were analyzed. Relationships between ionic strength and sorption capacity increments of cations and anions were determined. The results show that if ionic strength of the infiltrating solution to the volcanic ash soil is known, the ECEC (effective cation exchange capacity) and EAEC (effective anion exchange capacity) can be reliably estimated. The resulting prediction equations can be included to improve reactive transport simulation models. Consequently, it will be possible to better understand solute transport with changing sorption capacity for the solid soil phase. 相似文献
75.
Kenji Tsuruta Tomonori Kume Hikaru Komatsu Naoko Higashi Toshihiro Umebayashi Tomo’omi Kumagai Kyoichi Otsuki 《Journal of Forest Research》2010,15(6):398-403
Sap flow techniques are practical tools for estimating tree transpiration. Though many previous studies using sap flow techniques
did not consider azimuthal variations of sap flux density (F
d) on xylem trunk to estimate tree transpiration, a few studies reported that ignoring the azimuthal variations in F
d could cause large errors in tree transpiration estimates for some tree species. Therefore, examining azimuthal variations
in F
d for major plantation tree species is critical for estimating tree transpiration. Using the thermal dissipation method, we
examined azimuthal variations in F
d in six trees of Japanese cypress Chamaecyparis obtusa (Sieb. et Zucc.) Endl., which is one of the most common plantation tree species in Japan. We recorded considerable variations
among F
d at four different azimuthal directions. The F
d value for one aspect was more than 100% larger than those for the other aspects. We calculated differences between tree transpiration
estimates based on F
d for one to three azimuthal directions and those based on F
d for four aspects. The differences relative to tree transpiration estimates based on F
d for four aspects were typically 30, 20, and 10% in accordance with the F
d for one, two, and three measurement aspects, respectively. This finding indicates that ignoring azimuthal variations could
cause large errors in tree transpiration estimates for Japanese cypress. 相似文献
76.
Nutritional characteristics of the leaves of native plants growing in adverse soils of humid tropical lowlands 总被引:3,自引:0,他引:3
Osaki M Watanabe T Ishizawa T Nilnond C Nuyim T Shinano T Urayama M Tuah SJ 《Plant foods for human nutrition (Dordrecht, Netherlands)》2003,58(2):93-115
Acid sulfate, peat, sandy podzolic, and saline soils are widely distributed inthe lowlands of Thailand and Malaysia. The nutrient concentrations in theleaves of plants grown in these type of soils were studied with the aim ofdeveloping a nutritional strategy for adapting to such problem soils. In sagoand oil palms that were well-adapted to peat soil, the N, P, and Kconcentrations were the same in the mature leaves, while the Ca, Mg, Na,and Fe concentrations were higher in the mature leaves of the oil palm thanof the sago palm. Melastoma malabathricum and Melaleuca cajuputi plantsthat were well-adapted to low pH soils, peat, and acid sulfate soils were alsostudied. It was observed that a high amount of Al accumulated in the M.marabathricum leaves, while Al did not accumulate in M. cajuputi leaves.M. cajuputi plants accumulated large amounts of Na in their leaves or stemsregardless of the exchangeable Na concentration in the soil, while M.malabathricum that was growing in saline-affected soils excluded Na.Positive relationships between macronutrients were recognized between Pand N, between K and N, and between P and K. Al showed antagonisticrelationships with P, K, Ca, Mg, Fe, Zn, Cu, and Na. Na also showedantagonistic relationships with P, K, Zn, Mn, Cu, and Al. Fe showed weakantagonistic relationships with Zn, Mn, Cu, and Al. 相似文献
77.
Said AW Kodani M Usui T Fujimoto Y Ito T Yamaguchi T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(4):545-548
Embryonated chicken eggs (ECEs) are routinely used to isolate equine influenza virus. Propagation of the virus in ECEs results in selection of variants. In the present study, we determined nucleotide sequences of entire coding regions of parent A/equine/Tottori/1/07 (H3N8) and its derivatives that have different passage histories in ECE. After 12 passages, nucleotide sequence analysis predicted 3 amino acid substitutions in hemagglutinin (HA; 2 in HA1 and 1 in HA2). The two amino acid substitutions in HA1 were located in the vicinity of the cell receptor-binding site. Three other amino acid substitutions were predicted in internal proteins, 1 in the M1, 1 in the NP and 1 in the PA. This is the first report showing mutations in the internal protein genes of equine influenza virus associated with adaptation to ECE. 相似文献
78.
Onda K Sugiyama M Niho K Sato R Arai S Kaneko K Ito S Muto M Suganuma T Wakao Y Wada Y 《The Canadian veterinary journal. La revue veterinaire canadienne》2011,52(6):667-669
This study investigated the long-term survival of a calf with cervical ectopia cordis that grew normally, became pregnant, and calved normally. The cow showed normal cardiac function and absence of peripheral circulation abnormalities. This paper documents antemortem characteristics of the affected cow. 相似文献
79.
Okayama T Matsuno Y Yasuda N Tsukui T Suzuta Y Koyanagi M Sakaguchi M Ishii Y Olivry T Masuda K 《Veterinary immunology and immunopathology》2011,139(2-4):99-106
As IgE plays a pivotal role in type I hypersensitivity-mediated allergic diseases, it is valuable to measure absolute quantity of serum antigen-specific IgE for clinical and research purposes. Here we describe a novel ELISA system that enables quantification of antigen-specific IgE in ng/ml in dogs. A newly developed monoclonal antibody (CRE-DM) was shown to recognize canine and mouse IgE equally in a dose dependent manner, but it did not recognize canine IgG. The reactivity of CRE-DM to canine IgE was also confirmed by an inhibition ELISA using canine IgE as an inhibitor and the maximum inhibition rate was 91.3%. In order to know whether canine IgE specific to an allergen could be quantitatively measured with an ELISA using CRE-DM, we established a quantitative ELISA that could measure canine IgE recognizing Cry j 1, one of the major allergens of Japanese cedar pollen. In this ELISA, a standard curve was created by using concentration-predetermined Cry j 1-specific monoclonal mouse IgE. According to the standard curve, the concentration of Cry j 1-specific IgE in dogs that were experimentally sensitized to Japanese cedar pollen could be calculated and determined in ng/ml. The specificity of the Cry j 1-specific IgE ELISA using CRE-DM was also confirmed by inhibition ELISA using canine IgE as an inhibitor and the inhibition rate was 97.0%. Reproducibility of the ELISA in three independent assays was determined using groups of pooled canine sera whose Cry j 1-IgE titers ranged from 155.9 to 888.2 ng/ml. Intra- and inter-assay reproducibility was determined with coefficient of variation ranging between 3.1-5.2% and 2.2-8.0%, respectively. These results demonstrated that the ELISA utilizing CRE-DM was a specific, reliable and robust new laboratory test that could quantify absolute amount of antigen-specific IgE in canine serum. The ELISA will serve as a useful tool in the clinics to evaluate the change of serum IgE titers during anti-allergic treatments as well as during seasonal fluctuation of allergen exposure. 相似文献
80.
Toshihiro Okamura Kazuo Ishii Motohide Nishio Guilherme J. M. Rosa Masahiro Satoh Osamu Sasaki 《Animal Science Journal》2020,91(1)
Direct selection for litter size or weight at weaning in pigs is often hindered by external interventions such as cross‐fostering. The objective of this study was to infer the causal structure among phenotypes of reproductive traits in pigs to enable subsequent direct selection for these traits. Examined traits included: number born alive (NBA), litter size on day 21 (LS21), and litter weight on day 21 (LW21). The study included 6,240 litters from 1,673 Landrace dams and 5,393 litters from 1,484 Large White dams. The inductive causation (IC) algorithm was used to infer the causal structure, which was then fitted to a structural equation model (SEM) to estimate causal coefficients and genetic parameters. Based on the IC algorithm and temporal and biological information, the causal structure among traits was identified as: NBA → LS21 → LW21 and NBA → LW21. Owing to the causal effect of NBA on LS21 and LW21, the genetic, permanent environmental, and residual variances of LS21 and LW21were much lower in the SEM than in the multiple‐trait model for both breeds. Given the strong effect of NBA on LS21 and LW21, the SEM and causal information might assist with selective breeding for LS21 and LW21 when cross‐fostering occurs. 相似文献