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31.

Japanese star anise (Illicium anisatum L., JSA) is seriously damaged by a ringspot disease in Japan. Herein, to determine the causal agent using high-throughput sequencing, we discovered viral RNAs associated with JSA ringspot disease. We then determined the complete or near-complete nucleotide sequences of these RNAs using Sanger sequencing and RACE. The complementary strand of viral RNAs 1, 2, 3, 4, and 5 encoded a single protein, which shared sequence identity with P1 (RNA-dependent RNA polymerase), P2 (glycoprotein precursor), P3 (nucleocapsid protein), P4 (movement protein), and a protein with unknown function of emaraviruses (genus Emaravirus), respectively; however, the highest amino acid sequence identity for the P1–P5 proteins between JSARaV and known emaraviruses was 41.9%, 30.0%, 30.1%, 52.2%, and 38.0%, respectively, all of which were lower than the species demarcation criterion. Furthermore, RNA segments harbored conserved 12-nt terminal sequences at the 5′- and 3′-termini, and a high complementarity of approximately 20 nt in 5′- and 3′-terminal sequences. Transmission electron microscopy confirmed the presence of virus-like particles. JSA ringspot disease was found to be transmitted by an eriophyid mite (subclass Acari, superfamily Eriophyoidea) that belongs to the family Diptilomiopidae. Taken together, these results identified the virus responsible for the ringspot disease of JSA as a new member of the genus, Emaravirus, which we named as the Japanese star anise ringspot-associated virus (JSARaV). Moreover, this is the first report noting that eriophyid mites of the family Diptilomiopidae are capable of transmitting emaravirus.

  相似文献   
32.
Bottom-up and governance paradigms are becoming more prevalent in rural community planning in East Asia. Rural communities must enhance their institutional capacities, which are the baseline for planning future changes. However, few studies have analyzed the relationship between institutional capacity and rural community planning. Using a quantitative method of event history analysis, we compared the hazards of establishing conferences and plan approval from the Sato-dzukuri of Kobe City, Japan. We examined the effect of institutional capacity on rural community planning for the conference establishment and plan approval. We found that knowledge resources and relational resources are related to the proxy mobilization capacity for conference establishment. These resources are related to plan approval, although no relationship exists between conference establishment and plan approval. Conferences can be planned more rapidly than plans for approval can be, although both require substantial time. Communities with rural contexts present more rapid conference establishment than do suburban areas, whereas there are no significant differences in plan approval. This suggests that rural communities require more effort for the plan approval process. Rural community planning should judiciously address issues of institutional capacity regarding restrained knowledge resources and progress management, and should maintain vigilance regarding administration to achieve local governance.  相似文献   
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34.
Erratum     
The oxidation of nitric oxide (NO) to nitrogen dioxide (NO2), the initial step in formation of nitric acid, was analyzed based on atmospheric observations in urban central Osaka, Japan, focusing the relation with the behavior of photoreactive hydrocarbon (HC) species. Simultaneous observation at two vehicle exhaust monitoring stations, one has higher oxidation ratio of NO (NO2/NOx) and the other has lower NO2/NOx, in November 1998 and May 1999, had been held and investigated in current report. By using concentration ratios of reactive HCs to acetylene, obvious relation between NO2/NOx and HCs reaction was implied. In November observations, decline of aromatics to acetylene ratios with increasing NO2/NOx were observed at one station, while not appeared at the other station. Opposite tendencies were observed at the two sampling stations from November to May, implying complicated regional characteristics of photochemistries.  相似文献   
35.
Three known saponins, chiisanoside, 11-deoxyisochiisanoside, and isochiisanoside, and one novel saponin, 3,4-seco-4(23),20(29)-lupadiene-3,28-dioic acid 28-O-alpha-l-rhamnopyranosyl (1-->4)-beta-d-glucopyranosyl (1-->6)-beta-d-glucopyranoside, referred to as sessiloside, were isolated from a hot water extract of Acanthopanax sessiliflorus leaves. All of these saponins were lupane-type triterpene triglycosides, and their concentrations were 4.1, 1.0, 0.5, and 0.4% (w/w) of the total extract, respectively. Sessiloside and chiisanoside inhibited pancreatic lipase activity in vitro, and addition of the saponin-rich fraction to a high-fat diet suppressed the body weight gain of mice. The possibility of application of the lupane-type saponins from A. sessiliflorus leaves to the treatment of obesity is discussed.  相似文献   
36.
Genetic improvement of resistance to infectious diseases is a challenging goal in animal breeding. Infection resistance involves multiple immunological characteristics, including natural and acquired immunity. In the present study, we developed an experimental model based on genetic selection, to improve immunological phenotypes. We selectively established three mouse lines based on phagocytic activity, antibody production and the combination of these two phenotypes. We analyzed the immunological characteristics of these lines using a lipopolysaccharide (LPS), which is one of the main components of Gram‐negative bacteria. An intense immunological reaction was induced in each of the three mouse lines. Severe loss of body weight and liver damage were observed, and a high level of cytokine messenger RNA was detected in the liver tissue. The mouse line established using a combination of the two selection standards showed unique characteristics relative to the mouse lines selected on the basis of a single phenotype. Our results indicate that genetic selection and breeding is effective, even for immunological phenotypes with a relatively low heritability. Thus, it may be possible to improve resistance to infectious diseases by means of genetic selection.  相似文献   
37.
The T-wave of the patellar tendon reflex (PTR) was recorded in 24 neurologically normal dogs. The surface electromyogram (EMG) was recorded as the T-wave from the vastus lateralis muscle (VL) in response to percussion of the patellar tendon. The distance of the reflex arc (DRA) was measured along the straight line between the spinous process of L5 and the greater trochanter (GT), and between GT and the patellar ligament (PL). There was a significant correlation (P<0.001) of the latency with the DRA on each side, but no difference in the slopes of the relationships between right and left VL was shown. The regression line between the DRA and the latency of all data was Y = 0.0216X + 1.693, where Y = latency in ms, X = DRA in mm. The mixed sensory-motor conduction velocity was estimated as 84.6 +/- 5.5 m/s. In contrast, there was no significant correlation between the DRA and the amplitude of the T-waves. The mean (mean-CV) and standard deviation (SD-CV) of all CV (coefficient of variation) in each dog were 9.14 +/- 3.65% in latency and 3.54 +/- 1.14% in amplitude, indicating that the use of a simple hand-held reflex hammer is sufficient to record the reproducible T-wave of the PTR even in unanesthetized dogs. This method was applied to a case with minimal paraparesis, and the latency of the T-wave of the PTR in the right hind limb with slight proprioceptive deficit was outside of the upper limit of the 95% confidence interval between latency and the DRA. In conclusion, this method may be used in neurological diagnosis to quantify more precisely the PTR in dogs.  相似文献   
38.
The effect of lipopolysaccharide (LPS) on humoral and cell-mediated immunity was assessed using LPS-sensitive C3H/HeN mice. A single injection of LPS significantly decreased the anti-sheep red blood cells (SRBC) antibody titers, but not the number of anti-SRBC antibody producing spleen cells. In contrast, double LPS injection did not significantly decrease the anti-SRBC titers and even increased the number of anti-SRBC antibody producing spleen cells. Similarly, single LPS injection significantly suppressed the swelling of the footpad, but double LPS injection caused milder suppression. These results suggest that a difference in the level and timing of exposure to LPS may influence the immune response to infection or vaccination.  相似文献   
39.
We isolated a cellulase from the digestive organs of the short-spined sea urchin Strogylocentrotus intermedius using a combination of ion-exchange chromatography and gel filtration together with an assay for carboxymethylcellulase activity. The isolated cellulase was stained as a single band by Congo red. The molecular weight of the isolated cellulase, as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis under reducing conditions, was 59?kDa. The isolated cellulase exhibited hydrolytic activity toward carboxymethyl cellulose, with an optimum temperature and pH of 30?°C and pH 8.0, respectively. The thermal stability of the enzyme was characterized by determining the temperature at which activity decreased by 50?% with treatment for 30?min at pH 7.0 and found to be 32?°C. Cellulase activity remained at a high level at 5?C20?°C, which is the growth temperature of the short-spined sea urchin. These results confirm that the short-spined sea urchin should preferably be reared at a water temperature of <20?°C.  相似文献   
40.
An anatomical study of the canker onMaackia amurensis var.buergeri was carried out. The initial symptoms appeared as a longitudinal series of swellings and slightly swollen bark. First, anatomical abnormalities appeared near the cambial zone. Xylem formation was suppressed and hyperplasia of irregular ray parenchyma cells occurred, then the swellings appeared. The irregular cells increased in number, then, the surface of swollen bark burst. The ruptured swellings coalesced to form long irregular cankers. A part of this paper was presented at the 106th Meeting of the Jpn. For. Soc. (1994).  相似文献   
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