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351.
Haga T Murayama N Shimizu Y Saito A Sakamoto T Morita T Komase K Nakayama T Uchida K Katayama T Shinohara A Koshimoto C Sato H Miyata H Katahira K Goto Y 《Comparative immunology, microbiology and infectious diseases》2009,32(5):395-406
Measles virus (MeV) vaccine strain, AIK-C, is temperature sensitive (ts), which is thought to be associated with attenuation of virus pathogenicity. In this study, replication and antibody response were examined in cotton rats using viruses carrying different forms of the P gene, which is responsible for the ts phenotype of strain AIK-C and its parental Edmonston strain. When cotton rats were inoculated intranasally, ts viruses neither replicated in lungs, nor reproducibly generated an antibody response. When inoculated intramusculary (i.m.), however, ts strains raised an antibody titer in all animals. This response was not observed when ultraviolet-inactivated virus was used. ts virus, inoculated i.m., was recovered from cotton rat drainage lymph nodes. These results suggest that ts virus, inoculated i.m., could replicate in the cotton rat, presumably at the superficial lymph node, and induce an antibody response. Therefore, cotton rats can serve as a small-animal model for investigating immune responses to safer ts vaccine, as well as recombinant vaccine using AIK-C as a vector for protection against other infectious agents. 相似文献
352.
European Journal of Forest Research - The form-factor for the stem surface area is directly proportional to the square root of the form-factor for the stem volume, i.e., the square root law of the... 相似文献
353.
The occurrence of NADPH-dependent glutamate dehydrogenase (GDH) was studied in higher plants. All of the higher plants tested had both NADH- and NADPH-dependent GDH activities, based on the following observations: 1) NADPHdependent GDH activity was found in the extracts of corn and soybean leaves, which was free of NADPH-dehydrogenase by heat treatment or DEAE-cellulose column chromatography. 2) Radish leaves and roots grown under germ-free condition showed the same NADPH-dependent GDH activity as those grown under conventional condition. 3) No conversion of NADPH to NADH in the reaction mixture was demonstrated by measuring alcohol dehydrogenase activity. Moreover, it was ascertained that rice plant cells grown on suspension culture had 50% of NADPH-dependent GDH activity, and both activities were not affected by nitrogen sources. 相似文献
354.
Akio Morita Hiroshi Takano Mitsuru Oota Tadakatsu Yoneyama 《Soil Science and Plant Nutrition》2013,59(4):585-593
Forty-two-day-old wheat (Triticum aestivum L. var. Asakazekomugi) plants were treated with complete, K-free (—K), Ca-limited (—Ca), and Mg-free (—Mg) nutrient solutions for 10 days using 2 mM NH4NO3 as the nitrogen source, which was replaced with 4 mM 15 NH4C1 or Na15NO3 for the subsequent 2 days to investigate the absorption, translocation, and assimilation of inorganic nitrogen in relation to the mineral supply. In another experiment plants were grown on NO3 ?, NH4 +, NH4N03, and K-free and Ca-limited NH4N03 nutrient solutions for 10 days, and then in the latter three treatments the nitrogen source was replaced with NO3 ? and half of the —K plants received K for 6 days to examine the changes in the nitrate reductase activity (NRA). Wheat plants absorbed NH4 ?N and NO3-N at a similar rate. Influence of K on the absorption of N03-N was stronger than that on the absorption of NH4-N in wheat plants. The supply of K to the —K plants increased the absorption of NO3-N, while the absorption of NH4-N still remained at a lower rate in spite of the addition of K. A limited supply of Ca and lack of Mg in nutrient media slightly affected the absorption of NH4-N. The influence of K was stronger on the translocation of nitrogen from roots to shoots, while Ca and Mg had little effect. When K was supplied again to the —K plants the translocation of NO3,-N was more accelerated than that of NH4-N. Incorporation of NH4-N into protein was higher than that of NO3-N in all the tissues; root, stem, and leaf. Assimilation of NH4-N and NO3-N decreased by the —K and —Mg treatments. Leaf NRA of wheat plants decreased in the —K and —Ca plants. Higher leaf NRA was found when K was given again to the —K plants than when the plants were continuously grown in K-free media. Replacement of NO3 ? with NH4 + as the nitrogen source caused a decline of leaf NRA, while the supply of both NH4 ?N and NO3-N slightly affected the leaf NRA. 相似文献
355.
Akio Inoue 《林业研究》2013,24(3):525-530
We investigated the culm form for one of the largest bamboo species, Phyllostachys pubescens Mazel ex Houz. in relation to the mechanical constraint principles, i.e., elastic, stress and geometric similarity. The fine-resolution analysis of the culm taper indicated that the culm for P. pubescens consisted of three or four segments with various forms, except for the butt swell. This implied that the taper of the whole culm for P. pubescens could be expressed by neither of these principles. The regression slope between culm height and diameter at breast height on the double logarithmic coordinates was 0.629, which was significantly different from the values predicted from these principles. In conclusion, none of these mechanical constraint principles can express the culm taper and height-diameter relationship, and there may be a need for a more complicated model to express the culm form for P. pubescens. 相似文献
356.
Kei Sawata Yosuke Shigemoto Takuro Hirai Akio Koizumi Yoshihisa Sasaki 《Journal of Wood Science》2013,59(3):255-261
Shear tests were conducted on nailed joints in wood that were loaded perpendicular to the grain; these joints had 21 specifications depending on different combinations of wood species, nail dimensions, number of nails, and edge distances of the main members, and their effects on the shear resistance of the nailed joints were also investigated. The nailed joints with CN75 nails had higher initial stiffness than the joints with CN50 nails, provided the initial stiffness of nailed joints connected with 3 or 5 nails was not always a simple product of the number of nails and the initial stiffness of nailed joints connected with a nail, and instead depended on the combination of wood species of the main member and nail dimensions. When the edge distance decreased, the maximum load and energy capacity decreased, thereby affecting the energy capacity. The maximum load of the nailed joints with CN75 nails may be smaller than those with CN50 nails depending on the combination of wood species and nail dimensions. When the edge distance of the nailed joints was less than 26 mm, the energy capacity of the nailed joints with CN75 nails was less than or similar to those with CN50 nails. 相似文献
357.
Rauch PJ Chudnovskiy A Robbins CS Weber GF Etzrodt M Hilgendorf I Tiglao E Figueiredo JL Iwamoto Y Theurl I Gorbatov R Waring MT Chicoine AT Mouded M Pittet MJ Nahrendorf M Weissleder R Swirski FK 《Science (New York, N.Y.)》2012,335(6068):597-601
Recognition and clearance of a bacterial infection are a fundamental properties of innate immunity. Here, we describe an effector B cell population that protects against microbial sepsis. Innate response activator (IRA) B cells are phenotypically and functionally distinct, develop and diverge from B1a B cells, depend on pattern-recognition receptors, and produce granulocyte-macrophage colony-stimulating factor. Specific deletion of IRA B cell activity impairs bacterial clearance, elicits a cytokine storm, and precipitates septic shock. These observations enrich our understanding of innate immunity, position IRA B cells as gatekeepers of bacterial infection, and identify new treatment avenues for infectious diseases. 相似文献
358.
Yoshitake Takada Ippei Tayama Takashi Sayama Hiroko Sasama Masayasu Saruta Akio Kikuchi Masao Ishimoto Chigen Tsukamoto 《Breeding Science》2012,61(5):639-645
Saponins are sterols or triterpene glycosides that are widely distributed in plants. The biosynthesis of soybean saponins is thought to involve many kinds of glycosyltransferases, which is reflected in their structural diversity. Here, we performed linkage analyses of the Sg-3 and Sg-4 loci, which may control the sugar chain composition at the C-3 sugar moieties of the soybean saponin aglycones soyasapogenols A and B. The Sg-3 locus, which controls the production of group A saponin Af, was mapped to chromosome (Chr-) 10. The Sg-4 locus, which controls the production of DDMP saponin βa, was mapped to Chr-1. To elucidate the preference of sugar chain formation at the C-3 and C-22 positions, we analyzed the F2 population derived from a cross between a mutant variety, Kinusayaka (sg-10), for the sugar chain structure at C-22 position, and Mikuriya-ao (sg-3), with respect to the segregation of the composition of the group A saponins, and found that the formation of these sugar chains was independently regulated. Furthermore, a novel saponin, predicted to be A0-γg, 3-O-[β-d-galactopyranosyl (1→2)-β-d-glucuronopyranosyl]-22-O-α-l-arabinopyranosyl-soyasapogenol A, appeared in the hypocotyl of F2 individuals with genotype sg-10/sg-10
sg-3/sg-3. 相似文献
359.
Katsumi Takaba Teruyoshi Imada Shigehisa Katsumata Hiroshi Okumura Sachiko Iwamoto Yui Suzuki Minami Imaizumi Kensuke Myojo Chie Takada Naoya Kimoto Koji Saeki Itaru Yamaguchi 《Journal of toxicologic pathology》2012,25(4):265-271
This study histopathologically and immunohistochemically investigated a spontaneously
occurring single mass subcutaneously located in the left lower abdomen of a female
BALB/cAJcl−nu/+ mouse at 10 weeks of age. The mass was about 20 × 15 × 10 mm
in size after formalin fixation; nevertheless, it was not detected by clinical observations at
9 weeks of age. H&E staining revealed the tumor origin was epithelial and probably arose
from the mammary gland, and the tumor cells demonstrated a squamous, acinar or polyhedral/basal
pattern. A cell kinetics analysis revealed that many of the tumor cells of the squamous, acinar
or polyhedral/basal component were positive for PCNA and cyclin D1, although there were a few
of TUNEL-positive tumor cells in all of the components. An epithelial/mesenchymal analysis
demonstrated that most of the tumor cells of the squamous and acinar components contained
keratin and E-cadherin; however, most of the tumor cells of the polyhedral/basal component were
less or very weakly positive for these markers. The tumor cells of the squamous component were
negative for vimentin and SMA; however, many of the tumor cells of the polyhedral/basal
component exhibited vimentin. In addition, expression of SMA was confirmed in some tumor cells
of the acinar and basal components. Based on the microscopic and immunohistochemical
characterizations, the tumor was diagnosed to be adenosquamous carcinoma that originated from
the mammary gland with rapid growth, and the tumor cells demonstrated epithelial-mesenchymal
transition-like changes. 相似文献
360.
Watanabe O Ogino M Iwamoto A Akiyama T Miki T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(5):575-582
From April 1994 to March 2001, monitoring tests (surveillance) for contamination of Salmonella Enteritidis (SE) at commercial egg farms and farm traceback inspections for cases of SE foodborne illness were carried out in the Himeji Livestock Hygiene Service Center jurisdiction of Hyogo Prefecture, Japan. SE vaccination was not performed before the outbreak of SE-associated foodborne illness, and SE contamination of a farm was recognized. In the surveillance, the year average percentages of identified SE-positive farms were 6.1% in farms with floor feeding in an open-type henhouse (F-OH) and 12.7% in farms with cage feeding in a windowless-type henhouse (C-WH), but 0% in farms with only cage feeding in an open-type henhouse (C-OH). The highest identified proportion of SE-positive farms among all styles of farms was found (4.3%) in April 1997-March 1999. Farm traceback inspections were performed in 2 of 7 farms feeding by F-OH and in 5 of 9 farms feeding by C-WH in this period. Easier contamination with SE was found for C-WH or F-OH than for C-OH. Ninety percent of the birds (3,632,000 birds at 70 farms) are fed at these easier contamination farms by C-WH (89% of birds in 13% of farms) or F-OH (1% of birds at 10% of farms). Integrated sanitary requirements and SE vaccinations are especially necessary on farms feeding by F-OH or C-WH. Since 1999, these countermeasures have been performed, and SE foodborne illnesses and affected patients in Hyogo Prefecture have gradually decreased. 相似文献