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91.
The roughness parameters on the material ratio curves were related to tactile roughness for samples of buna and mizunara. The surfaces of the samples were sanded using various grades of coated abrasives and the roughness parameters, reduced peak height (Rpk), core roughness depth (Rk), and reduced valley depth (Rvk), were estimated on the material ratio curves, which were obtained from roughness profiles determined using robust Gaussian regression filter. The values of Rpk and Rk were almost the same for buna and mizunara under the same sanding conditions and increased exponentially with tactile roughness. The coefficients of determination of those parameters and tactile roughness were higher than 0.79 at all cutoff wavelengths. On the other hand, the value of Rvk for mizunara was significantly larger than that for buna because of the deep local valleys. There was no relationship between Rvk and tactile roughness for both species.  相似文献   
92.
An acidic polysaccharide (APS) was isolated from the extract of Cordyceps militaris grown on germinated soybeans. Analyses of sugar composition indicated that APS consisted of d-galactose, L-arabinose, D-xylose, L-rhamnose, and D-galacturonic acid. On the basis of the result of methylation analysis, APS was considered to be mainly composed of Araf-(1-->, -->5)-Araf-(1-->, -->4)-Galp-(1--> and -->4)-GalAp-(1--> residues. When the polysaccharide was intranasally administered, it decreased virus titers in the bronchoalveolar lavage fluid and the lung of mice infected with influenza A virus and increased survival rate. Furthermore, APS increased TNF-alpha and IFN-gamma levels in mice when compared with those of untreated mice. APS enhanced nitric oxide (NO) production and induced iNOS mRNA and protein expressions in RAW 264.7 murine macrophage cells. The induction of mRNA expression of cytokines including IL-1beta, IL-6, IL-10, and TNF-alpha was also observed. These results demonstrated that APS might have beneficial therapeutic effects on influenza A virus infection at least in part by modulation of the immune function of macrophages.  相似文献   
93.
Intestinal helminth and protozoan infection in the quarantined dogs in Taiwan were examined using fecal examination between January to December, 2004. Of the 376 dogs imported from 11 countries, 63 (16.8%) were found to be infected with at least one species of intestinal parasite. The parasites detected were oocysts of Isospora canis and eggs of Toxocara canis, Trichuris vulpis and hookworms. Of the 63 infected dogs, 11 were found to have a mixed infection of two different species of parasites. This paper illustrates that parasites are transmitted from one country to another through the transport of animals. Moreover, there is also a possibility of parasitic infection among quarantined dogs as well as the zoonotic potential for quarantine officers during the quarantine period.  相似文献   
94.
For evaluation of physiologically significant organic anions in the colonic environment, 87 samples of normal feces were collected from the rectum of 15 calves less than 60 days old. The calves were fed milk replacer with free access to starter diet and hay. After fecal extraction with water, pH, D- and L-lactate, succinate, and volatile fatty acid (VFA) concentrations were determined. There was wide variation in fecal pH (4.3 to 7.7). Higher lactate concentrations were observed in feces samples with lower pH, and most of these samples were collected during the first 4 weeks of life. Elevated lactate concentrations included both the D- and L-isomers, and the D-isomer comprised approximately 30-50% of total lactate. Elevated succinate concentrations were observed in only 8 fecal samples, while other samples had lower or trace amounts of succinate. Elevated fecal succinate showed no relationship with fecal pH or VFA concentrations. Fecal VFA concentrations were lower in samples collected in the early postnatal stage, but fecal VFA concentrations were not necessarily related to age. We confirmed that fecal D- and L-lactate concentrations increased with a concomitant decrease of VFA in the acidic lumen of the colon, although acidic feces were not necessarily accompanied by elevated concentrations of lactate. In contrast, succinate production was not related to fecal pH or VFA concentrations.  相似文献   
95.
In 117 livers with fascioliasis, this study was focused on the number of Fasciola, the number and intrahepatic localization of affected hepatic ducts and bile ducts, and the degree of fibrosis in the hepatic segments and bile ducts. The degree of pathological changes in bile ducts caused by fascioliasis was classified into five levels. The site of Fasciola habitation was most often the hepatic ducts of the porta hepatis: it was the left hepatic duct in 101 livers and the right hepatic duct in 88 livers. Casts were prepared by infusing synthetic resin into the hepatic arterial, portal, hepatic venous and biliary systems of 15 bovine livers with fascioliasis and then examined. In the left lobe, quadrate lobe, and caudate process where atrophic fibrosis was noted, the bile ducts became rod-shaped by losing branches, and the samples resembled dead branches of liver. Portal branches were thinned or completely terminated with marked fibrosis. Fine and irregular newly formed bile ducts not parallel with portal branches were observed in livers with markedly chronic fascioliasis. Distal portal branches in the right lobe, caudate lobe, and papillary process showed hypertrophic proliferative changes. The arterial system was generally well developed in thickened walls of bile ducts and formed vascular beds, and surrounded the bile ducts as tubes. In livers with severe fibrosis, capillaries were markedly developed and resembled glass cotton.  相似文献   
96.
We describe a pathogenetic mechanism underlying a variant form of the inherited blood disorder alpha thalassemia. Association studies of affected individuals from Melanesia localized the disease trait to the telomeric region of human chromosome 16, which includes the alpha-globin gene cluster, but no molecular defects were detected by conventional approaches. After resequencing and using a combination of chromatin immunoprecipitation and expression analysis on a tiled oligonucleotide array, we identified a gain-of-function regulatory single-nucleotide polymorphism (rSNP) in a nongenic region between the alpha-globin genes and their upstream regulatory elements. The rSNP creates a new promoterlike element that interferes with normal activation of all downstream alpha-like globin genes. Thus, our work illustrates a strategy for distinguishing between neutral and functionally important rSNPs, and it also identifies a pathogenetic mechanism that could potentially underlie other genetic diseases.  相似文献   
97.
The intensity of Galactic cosmic rays is nearly isotropic because of the influence of magnetic fields in the Milky Way. Here, we present two-dimensional high-precision anisotropy measurement for energies from a few to several hundred teraelectronvolts (TeV), using the large data sample of the Tibet Air Shower Arrays. Besides revealing finer details of the known anisotropies, a new component of Galactic cosmic ray anisotropy in sidereal time is uncovered around the Cygnus region direction. For cosmic-ray energies up to a few hundred TeV, all components of anisotropies fade away, showing a corotation of Galactic cosmic rays with the local Galactic magnetic environment. These results have broad implications for a comprehensive understanding of cosmic rays, supernovae, magnetic fields, and heliospheric and Galactic dynamic environments.  相似文献   
98.
The relationship between the taxa of airborne fungi and the decay risk was investigated. Airborne fungi in 1,000 l of air were trapped on Japanese cedar disks, and incubated in a damp container kept at 26oC. After 16-week incubation, filamentous fungi grown on the disks were isolated and DNA extracted from each isolate was amplified with the primers ITS4/ITS5. The DNA sequences of the amplified products were determined and compared to the sequence data of GenBank to determine the species or genus according to a BLAST search. This search revealed that the isolate consisted of 5 major taxa, namely Bjerkandera sp., Phanerochaete sp. (A), Phanerochaete sp. (B), Polyporales sp. Polyporus arcularius, and 6 minor ones. Statistical analysis revealed that the major taxa were trapped on the disks in similar weather conditions except for Bjerkandera sp., which was trapped at a cooler temperature. The analysis also proved the disks to which Phanerochaete spp. or Polyporales sp. were attached showed higher mass loss. It is concluded that, under these experimental conditions, related species of Phanerochaete sordida play an important role in increasing the decay risk caused by airborne wood-decay fungi.  相似文献   
99.
Soybean cyst nematode (SCN) (Heterodera glycines Ichinohe) is one of the most damaging pests of soybean (Glycine max (L.) Merr.). Host plant resistance has been the most effective control method. Because of the spread of multiple SCN races in Hokkaido, the Tokachi Agricultural Experiment Station has bred soybeans for SCN resistance since 1953 by using 2 main resistance resources PI84751 (resistant to races 1 and 3) and Gedenshirazu (resistant to race 3). In this study, we investigated the genetic relationships of SCN resistance originating from major SCN resistance genes in Gedenshirazu and PI84751 by using SSR markers. We confirmed that race 1 resistance in PI84751 was independently controlled by 4 genes, 2 of which were rhg1 and Rhg4. We classified the PI84751- type allele of Rhg1 as rhg1-s and the Gedenshirazu-type allele of Rhg1 as rhg1-g. In the cross of the Gedenshirazu-derived race 3-resistant lines and the PI84751-derived races 1- and 3-resistant lines, the presence of rhg1-s and Rhg4 was responsible for race 1-resistance. These results indicated that it was possible to select race 1 resistant plants by using marker-assisted selection for the rhg1-s and Rhg4 alleles through a PI84751 origin × Gedenshirazu origin cross.  相似文献   
100.
In vivo, nicotine in cigarette smoke induces various effects not only on the respiratory system but also the central and peripheral nerve systems, circulatory organs and digestive organs, and there is a possibility of promotion of lung tumorigenesis. The present experiment was conducted to examine histopathological changes caused by nicotine in the lung with repeated intratracheal instillation (i.t.). Six-week-old male F344 rats were administered nicotine by i.t. at doses of 0.05, 0.1 and 0.2 mg nicotine/rat every 3 weeks beginning at week 4, for up to a total of 9 times and were then sacrificed at week 30. The total number of administrations, total dose of nicotine and effective number of rats were 9 times, 0.45 mg and 5 rats and 4 times, 0.20 mg and 5 rats for the 0.05 mg nicotine/rat group; 3 times, 0.30 mg and 5 rats and 4 times, 0.40 mg and 3 rats for the 0.1 mg group; and 3 times, 0.60 mg and 3 rats for the 0.2 mg group, respectively. As a control group, 5 rats were administered 0.2 ml saline/rat 9 times. Some rats administered 0.1 and 0.2 mg nicotine suffered convulsions just after administration. Histopathologically, though proliferative changes were not observed, neutrophil infiltration, edema and fibrosis in the lung were induced by nicotine. In conclusion, repeated treatment of nicotine promoted neurologic symptoms in the acute phase, and strong inflammation in the lungs in the chronic phase, even at a low dose. Toxicity of nicotine is suggested to depend not on total dose of nicotine in the experiment but rather on repeated injury with consecutive administration.  相似文献   
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