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131.
Large highly pathogenic avian influenza (HPAI) outbreaks caused by clade 2.3.4.4e H5N6 viruses occurred in Japan during the 2016–2017 winter. To date, several reports regarding these outbreaks have been published, however a comprehensive study including geographical and time course validations has not been performed. Herein, 58 Japanese HPAI virus (HPAIV) isolates from the 2016–2017 season were added for phylogenetic analyses and the antigenic relationships among the causal viruses were elucidated. The locations where HPAIVs were found in the early phase of the outbreaks were clustered into three regions. Genotypes C1, C5, and C6–8 HPAIVs were found in specific areas. Two strains had phylogenetically distinct hemagglutinin (HA) and non-structural (NS) genes from other previously identified strains, respectively. The estimated latest divergence date between the viral genotypes suggests that genetic reassortment occurred in bird populations before their winter migration to Japan. Antigenic differences in 2016–2017 HPAIVs were not observed, suggesting that antibody pressure in the birds did not contribute to the selection of HPAIV genotypes. In the late phase, the majority of HPAI cases in wild birds occurred south of the lake freezing line. At the end of the outbreak, HPAI re-occurred in East coast region, which may be due to the spring migration route of Anas bird species. These trends were similar to those observed in the 2010–2011 outbreaks, suggesting there is a typical pattern of seeding and dissemination of HPAIV in Japan.  相似文献   
132.
The method reported previously (Part I) was employed to prepare a variety of novel 6-acylsalicylates as key intermediates. 6-Acylpyrimidin-2-yl salicylates (2-acyl-6-[(4,6-disubstituted pyrimidin-2-yl)oxy]benzoate derivatives: Type 1), the closely related phthalide compounds (3-alkyl-7-[(4,6-dimethoxypyrimidin-2-yl)oxy]phthalide derivatives: Type 2) and the ketal derivatives of 2-acyl-6-[(4,6-dimethoxypyrimidin-2-yl)oxy]benzoates (Type 3) were synthesized and their herbicidal activities measured. Methyl 2-acetyl-6-[(4,6-dimethoxypyrimidin-2-yl)oxy]benzoate gave excellent control of barnyard grass with a promising profile as a prototype rice herbicide.  相似文献   
133.
Streptococcus suis is an important swine pathogen and a zoonotic agent causing meningitis and septicemia. Although serotype 2 is the most virulent type, serotype 14 is emerging, and understanding of its pathogenesis is limited. To study the role of the capsular polysaccharide (CPS) of serotype 14 as a virulence factor, we constructed knockout mutants devoid of either cps14B, a highly conserved regulatory gene, or neu14C, a gene coding for uridine diphospho-N-acetylglucosamine 2-epimerase, which is involved in sialic acid synthesis. The mutants showed total loss of the CPS with coagglutination assays and electron microscopy. Phagocytosis assays showed high susceptibility of mutant Δcps14B. An in vivo murine model was used to demonstrate attenuated virulence of this non-encapsulated mutant. Despite the difference in the CPS composition of different serotypes, this study has demonstrated for the first time that the CPS of a serotype other than 2 is also an important antiphagocytic factor and a critical virulence factor.  相似文献   
134.
Maropitant is a neurokinin 1 receptor (NK1R) antagonist that is clinically used as a new anti-emetic drug for dogs. Substance P (SP) and its receptor NK1R are considered to modulate gastrointestinal peristalsis. In addition, SP works as an inflammatory mediator in gastrointestinal diseases. Aim of this study is to clarify the effects of maropitant on intestinal motility and inflammation in mice. Ex vivo examination of luminal pressure-induced intestinal motility of whole intestine revealed that maropitant (0.1–10 µM) increased frequency of contraction, decreased amplitude of contraction and totally inhibited motility index in a concentration-dependent manner. We measured intestinal transit in vivo by measuring transportation of orally administered luminal content labeled with phenol red. Our results demonstrated that maropitant (10 mg/kg, SC) delayed intestinal transit. Geometric center value was significantly decreased in maropitant-treated mice. Anti-inflammatory effects of maropitant against leukocytes infiltration into the intestinal smooth muscle layer in post-operative ileus (POI) model mice were measured by immunohistochemistry. In POI model mice, a great number of CD68-positive macrophages or MPO-stained neutrophils infiltrated into the inflamed muscle region of the intestine. However, in the maropitant treated mice, the infiltration of leukocytes was not inhibited. The results indicated that maropitant has ability to induce disorder of intestinal motility in mice, but has no anti-inflammatory action in the mouse of a POI model. In conclusion, in mice, maropitant induces disorder of intestinal motility in vivo.  相似文献   
135.
A sensitive and reproducible enzyme-linked immunosorbent assay (ELISA) using two monoclonal antibodies directed against a synthetic peptide with an amino-acid sequence related to the C-terminus of bovine myoglobin and the whole molecule of sodium dodecyl sulphate (SDS)-denatured bovine myoglobin was adapted for detecting bovine myoglobin in contaminated feeds. The ELISA employed bovine meat extract of a known myoglobin concentration as a calibration standard and had an limit of detection (LOD) of 3.54 ng/ml and an limit of quantification (LOQ) of 11.0 ng/ml corresponding to 0.022% and 0.067% (wt/wt) bovine meat-and-bone-meal (MBM) mixed in 20-fold-diluted feed extracts, respectively. A cut-off threshold of 20.6 ng/ml bovine myoglobin was set to simplify ELISA and facilitate quick assessment of test results without a tedious calibration process. The ELISA was able to detect bovine MBM in artificially prepared model feeds, mixed botanical feeds, mixed botanical feeds with skimmed milk, fish meal, pork meal and pork/chicken meal at 0.1% (wt/wt). It was also able to detect sheep MBM in test feeds, but showed no reactivity to swine MBM, chicken MBM, skimmed milk or gelatine of bovine origin. The advantages of this method are the quick and easy extraction protocol of proteins from test feeds, using 100 mM sodium sulphide and 0.6% sodium dodecyl sulphate in the extraction solution and the effective detection of bovine and sheep MBM at 0.1% (wt/wt).  相似文献   
136.
A two-cycle accelerated aging boil test was conducted on kenaf core binderless boards to estimate their bond durability. This is one of the methods to estimate the bond quality of kenaf core binderless boards, as stipulated by Notification 1539 of the Ministry of Land, Infrastructure, and Transport, October 15, 2001, for the Building Standard Law of Japan. Generally, retention ratios of modulus of rupture (MOR), modulus of elasticity (MOE), and internal bond (IB) strength after the boil test increased with increased pressing temperature. In particular, the MOR retention ratio of boards with a pressing temperature of 200°C (average 106.4%) was higher than that of a commercial medium-density fiberboard (MDF) (melamine-urea-formaldehyde resin) (average 72.7%), and the value sometimes exceeded 100%. The durability of kenaf core binderless boards with a pressing temperature of 200°C compared favorably with that of the commercial MDF (melamine-urea-formaldehyde resin), having almost the same retained strength values after the boil test. Part of this article was presented at the International Symposium on Wood Science and Technology, IAWPS2005, November 27–30, 2005, Yokohama, Japan  相似文献   
137.
Collapse-type shrinkage is one of highly refractory drying defects in low-medium density plantation-grown eucalypt wood used as solid wood products. Basic density (BD), microfibril angle (MFA), double fibre cell wall thickness (DWT), proportion of ray parenchyma (RP), unit cell wall shrinkage, total shrinkage and residual collapse, which are associated with collapse-type shrinkage characteristics, were investigated by using simple regression method for three species of collapse-susceptible Eucalyptus urophyll, E. grandis and E.urophyllaxE.grandis, planted at Dong-Men Forest Farm in Guangxi autonomous region, China. The results indicated that : unit cell wall shrinkage had a extremely strong positive correlation with BD, moderately strong positive correlation with DWT, and a weakly or moderately negative correlation with RP and MFA; total shrinkage was positively correlated with BD, DWT and RP and negatively related to MFA, but not able to be predicted ideally by any examined factors alone owing to lower R^2 value (R^2≤0.5712); residual collapse was negatively correlated with BD and DWT, linearly positively correlated with MFA, and had strongly positive linear correlation with RP. It is concluded that BD can be used as single factor (R^2≥0.9412) to predicate unit cell wall shrinkage and RP is the relatively sound indicator for predicting residual collapse  相似文献   
138.
To provide basic information on self-bonding in kenaf core binderless boards, a series of chemical analyses was conducted on binderless boards and their chemical changes during hot pressing were examined in our previous study. In this study, binderless boards were manufactured under conditions that may accelerate the supposed chemical changes to investigate their effect on the board properties. First, to investigate the influence of the chemical bonds formed by carbonyl compounds on self-bonding, the influence of acetic acid addition prior to board manufacturing was studied and the effect of methanol extractives (containing the carbonyl compounds) was also examined. Second, the influence of the condensation reaction in lignin was discussed from the viewpoint of board density. Last, to examine the influence of thermal softening of lignin, the influences of temperature condition and moisture content, as well as those of microwave pretreatment, were investigated. As a result, the estimated chemical changes were suggested to influence the binderless board properties.  相似文献   
139.
Summary A Japanese leading cultivar ‘Konafubuki’ has an extreme resistance gene Ry chc to Potato virus Y (PVY) in a simplex fashion. To reduce complexity of the highly heterozygous autotetraploid genome and map the Ry chc gene, haploid plants were parthenogenetically induced from ‘Konafubuki’. The ratio of 7 resistant: 5 susceptible haploids confirmed the single dominant, simplex genotype of ‘Konafubuki’. A selected resistant haploid 98H20-5 was crossed with a susceptible diploid, resulting in 119 F 1 plants. Using RFLP and RAPD markers, Ry chc was mapped to the most distal end of the chromosome 9 where the recovery of recombinant genotypes was extremely reduced in this mapping population possibly due to the linked inferiority factor. The location of Ry chc is different from those of the other extreme resistance genes to PVY, but possibly resides in one of resistance gene clusters.  相似文献   
140.
Green onion and cabbage certified reference materials for the analysis of pesticide residues were issued by the National Metrology Institute of Japan, part of the National Institute of Advanced Industrial Science and Technology. Green onion and cabbage samples were grown so as to contain several kinds of organophosphorus and pyrethroid pesticides, and those were collected from a field in the Kochi Prefecture in Japan. The certification was carried out by using multiple analytical methods to ensure the reliability of analytical results; the values of target pesticides (diazinon, fenitrothion, cypermethrin, etofenprox, and permethrin for green onion and chlorpyrifos, fenitrothion, and permethrin for cabbage) were obtained by isotope dilution mass spectrometry. Certified values of target pesticides were 0.96-13.9 and 2.41-6.9 mg/kg for green onion and cabbage, respectively. These are the first green onion and cabbage powder certified reference materials in which organophosphorus and pyrethroid pesticides are determined.  相似文献   
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