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1.
K Ueda S Yamazaki S Yamamoto 《Nippon juigaku zasshi. The Japanese journal of veterinary science》1989,51(3):505-514
Intestinal infection by Mycobacterium avium was investigated in C57BL/6 and BALB/c mouse strains. Single intragastric administration of a massive dose (10(8] or multiple administration of a lower dose (10(7), 10 times) established infection principally in the mesenteric lymph-node (MLN); a continuous or intermittent fecal excretion of the bacilli was detected by 6-8 weeks after the administration. Based on three criteria--isolation of the organisms from the MLN and from feces, and detection of acid-fast bacilli in sections of the MLN--germ-free (GF) BALB/c mice exhibited clearer dose-effect relations than the flora-bearing (FB) counterparts. After intragastric administration, the organisms were probably trapped in the Peyer's patch and then transferred to the MLN at an early period (by 4-7 days), persistent infection thus being established in the MLN. Systemic involvement evolved both in athymic and euthymic mice after a prolonged period of time (more than 40 weeks) showing far more severe involvement in the former regardless of the presence of floral organisms. 相似文献
2.
3.
Hisayuki Arakawa Yohei Ohi Akira Matsumoto Kenji Takio Takumi Kimoto Katsutoshi Kawabe 《Fisheries Science》2012,78(5):1083-1090
The populations of red alga Gelidium elegans along the coast of Miyakejima Island were severely damaged by a volcanic eruption in 2000. The effect of this volcanic eruption has been long lasting, and populations of this red alga still have not recovered. We investigated the effect of seabed sediment particles derived from volcanic ash on the substrate adhesion of G.?elegans spores. The analysis provides evidence that increasing amounts of sediment particles result in lower adhesion rates of G.?elegans spores, and that smaller sediment particles have a greater influence on adhesion. The amount of seabed sediment particles around Miyakejima Island was 9.3?C1815.4?mg/cm2. This amount has changed greatly from year to year. The adhesion rate of G.?elegans spores in water around Miyakejima Island was 0?% at all points in 2008 and 2010, but it was estimated as 6.3?C38.6?% in 2009. These results suggest that there is significant inhibition of algal spore adhesion by seabed sediment particles derived from volcanic ash around Miyakejima Island. 相似文献
4.
Shintaro TOMURA Atsushi TOSHIMA Akira NOMURA Masahiko HIRATA Tetsushi YAMAGAMI Yumiko KAGAWA Tsuyoshi KADOSAWA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(3):439
An 11-year-old neutered male Domestic Shorthair cat presented with a 3-month history of hypoglycemia, two episodes of seizure, and intermittent tick-like signs. Serum biochemistry revealed severe hypoglycemia associated with high insulin concentrations. Dynamic abdominal computed tomography (CT) indicated two pancreatic masses, which were enhanced most during the late arterial phase but had different degrees and variations of attenuation. Partial pancreatectomy was performed. Histopathology and immunohistochemistry confirmed that one mass was an insulinoma and the other was an ectopic splenic tissue, consistent with the differences in imaging findings. When an intrapancreatic lesion with hyper-attenuation on dynamic abdominal CT is detected, not only insulinoma or metastasis of malignancies but also intrapancreatic accessory spleen (IPAS) should be considered as differential diagnoses. 相似文献
5.
Kiriko Nakamura Kiyoshi Matsubara Hitoshi Watanabe Hisashi Kokubun Yoshihiro Ueda Naomi Oyama-Okubo Masayoshi Nakayama Toshio Ando 《Scientia Horticulturae》2006
In order to identify genetic resources for breeding fragrant petunias for use as bedding plants, volatile compounds released by day from the flowers of 40 commercial Petunia hybrida cultivars were analyzed using a solid-phase micro-extraction technique coupled with GC–MS. The three cultivars with solid deep-blue flowers that accumulate malvidin in corollas with high tissue pH were found to emit abundant iso-eugenol as the principal floral fragrance. Several other cultivars that emitted considerable amounts of methylbenzoate and/or benzylbenzoate from the flower were also identified. Association between the floral fragrance and the other floral traits such as floral anthocyanin composition and corolla-tissue pH was discussed. 相似文献
6.
Mizuno S Sono Y Matsuoka T Matsumoto K Saeki K Hosoi Y Fukuda A Morimoto Y Iritani A 《The Journal of reproduction and development》2006,52(3):429-438
We previously identified a novel gonad-specific expression gene (Gse) and investigated its expression during gametogenesis in the mouse testis and ovary. In this study, we generated a polyclonal antibody to GSE protein and determined the profiles of the protein's expression in germ cells and preimplantation embryos in detail using immunocytochemical and immunofluorescence staining. In a Western blot analysis, the anti-GSE antibody recognized long and short isoforms (approximately 27.6 kDa and 23.1 kDa) of the protein in the mouse testis and the long isoform in the ovary. In the mouse testis, GSE protein was expressed in spermatocytes I in the pachytene stage, round spermatids, and elongated spermatids. In the mouse ovary, the protein was located in the cytoplasm and nucleus of all oocytes regardless of the stage of the ovarian follicles. In preimplantation embryos from the pronuclear to blastocyst stage, however, GSE protein was mainly detected in the nuclei of cells. At the blastocyst stage, the protein was confirmed to have accumulated in the inner cell mass (ICM), whereas it had mostly disappeared from the trophectoderm (TE). These findings suggest that GSE protein may play a role in the establishment of nuclear totipotency and may be associated with early lineage specification. 相似文献
7.
Nakayama T Yonekura-Sakakibara K Sato T Kikuchi S Fukui Y Fukuchi-Mizutani M Ueda T Nakao M Tanaka Y Kusumi T Nishino T 《Science (New York, N.Y.)》2000,290(5494):1163-1166
Aurones are plant flavonoids that provide yellow color to the flowers of some popular ornamental plants, such as snapdragon and cosmos. In this study, we have identified an enzyme responsible for the synthesis of aurone from chalcones in the yellow snapdragon flower. The enzyme (aureusidin synthase) is a 39-kilodalton, copper-containing glycoprotein catalyzing the hydroxylation and/or oxidative cyclization of the precursor chalcones, 2',4',6',4-tetrahydroxychalcone and 2',4',6',3,4-pentahydroxychalcone. The complementary DNA encoding aureusidin synthase is expressed in the petals of aurone-containing varieties. DNA sequence analysis revealed that aureusidin synthase belongs to the plant polyphenol oxidase family, providing an unequivocal example of the function of the polyphenol oxidase homolog in plants, i.e., flower coloration. 相似文献
8.
Akira Inoue Kohei Takadono Ryuji Nishiyama Kenji Tajima Takanori Kobayashi Takao Ojima 《Marine drugs》2014,12(8):4693-4712
A major alginate lyase, FlAlyA, was purified from the periplasmic fraction of an alginate-assimilating bacterium, Flavobacterium sp. strain UMI-01. FlAlyA showed a single band of ~30 kDa on SDS-PAGE and exhibited the optimal temperature and pH at 55 °C and pH 7.7, respectively. Analyses for substrate preference and reaction products indicated that FlAlyA was an endolytic poly(mannuronate) lyase (EC 4.2.2.3). A gene fragment encoding the amino-acid sequence of 288 residues for FlAlyA was amplified by inverse PCR. The N-terminal region of 21 residues except for the initiation Met in the deduced sequence was predicted as the signal peptide and the following region of six residues was regarded as propeptide, while the C-terminal region of 260 residues was regarded as the polysaccharide-lyase-family-7-type catalytic domain. The entire coding region for FlAlyA was subjected to the pCold I—Escherichia coli BL21(DE3) expression system and ~eight times higher yield of recombinant FlAlyA (recFlAlyA) than that of native FlAlyA was achieved. The recFlAlyA recovered in the periplasmic fraction of E. coli had lost the signal peptide region along with the N-terminal 3 residues of propeptide region. This suggested that the signal peptide of FlAlyA could function in part in E. coli. 相似文献
9.
We examined the contribution of rubberwood to the timber export markets of Malaysia and Thailand. In Malaysia, rubberwood
has grown from 26% of total exported wood products in 1998 to 35% in 2007. A high proportion of furniture products (80%) is
rubberwood, whereas the contribution of rubberwood to other wooden products is less than 20%. Only 10% of sawn timber and
logs is rubberwood. In Thailand, rubberwood contributes to around 60% of total exported wood products, arising from a high
share of not only furniture products (70%) but also other wood products (around 50%) and sawn timber and logs, which have
increased in share from 40% in 1998 to 79% in 2007. We conclude that the high proportion of rubberwood products in the wood
export markets of these two countries is a result of: (1) scarcity of raw wood materials because of strict controls on the
logging of natural forests; and (2) governmental support to rubberwood production, including financial support to rubber planters
and technical assistance to downstream timber processors. 相似文献
10.
Understory individuals were found to form patches in a 100-year-old deciduous broad-leaved forest. The closed forest canopy
was uniform, and so the light conditions at various locations across the forest floor differed little after the leaf flush
of the overstory. To explain the distribution pattern in the understory, a hypothesis was proposed: in spring, the forest
floor is divided into patches according to the timing of leaf flush of the overstory individuals, and the light conditions
are more favorable for understory plants under the crowns of trees with later-flushing leaves. In the plot, three groups of
early, intermediate, and late, were recognized in the overstory concerning the timing of leaf flush. As for the start of leaf
flush, a difference of 31.6 days was recognized among tree species, and for the end of leaf flush, a difference of 40.3 days.
In the spring of 1998, the relative photosynthetic-photon-flux density under an intensively studiedCastanea crenata tree (late-flushing species) usually showed higher values than that under a similarly studiedAcer mono tree (early-flushing species). Analysis of the spatial-distribution pattern using Morisita’s1δ index revealed that the understory community had an aggregated distribution. In the overstory, the late- and the intermediate-flushing-species
groups showed aggregated distributions, while the early-flushing-species group showed random distribution. Spatial correlation
between the understory and the overstory was analyzed by using Morisita’sRδ index. The distribution of whole understory community spatially co-occurred with that of the late-flushing-species group
of the overstory. In contrast, the understory community was less developed below the members of the early-flushing-species
group of the overstory. We consider that the data presented here support our hypothesis, and we suggest that the growth and
survival of understory individuals were promoted in the places receiving light for long periods in spring. 相似文献