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排序方式: 共有651条查询结果,搜索用时 31 毫秒
641.
642.
Tsukasa Maruoka Yasuhiko Nikaido Satoshi Miyahara Eisuke Katafuchi Yoshinori Inamasu Midori Ogawa Kazumasa Fukuda Toshiyuki Nakayama Takafumi Horishita Mitsumasa Saito 《PLoS neglected tropical diseases》2021,15(6)
BackgroundLeptospirosis has been described as a biphasic disease consisting of hematogenous dissemination to major organs in the acute phase and asymptomatic renal colonization in the chronic phase. Several observational studies have suggested an association between leptospirosis and chronic kidney disease (CKD). We investigated the dynamics of leptospires and histopathological changes in the kidney to understand the relationship between them, and also investigated the extent of renal dysfunction in the acute and chronic phases of leptospirosis using a hamster model.FindingsHamsters (n = 68) were subcutaneously infected with 1 × 104 cells of the Leptospira interrogans serovar Manilae strain UP-MMC-SM. A total of 53 infected hamsters developed fatal acute leptospirosis, and the remaining 15 hamsters recovered from the acute phase, 13 of which showed Leptospira colonization in the kidneys in the chronic phase. Five asymptomatic hamsters also had renal colonization in the chronic phase. Immunofluorescence staining showed that leptospires were locally distributed in the renal interstitium in the early acute phase and then spread continuously into the surrounding interstitium. The kidneys of the surviving hamsters in the chronic phase showed patchy lesions of atrophic tubules, a finding of chronic tubulointerstitial nephritis, which were substantially consistent with the distribution of leptospires in the renal interstitium. The degree of atrophic tubules in kidney sections correlated statistically with the serum creatinine level in the chronic phase (rs = 0.78, p = 0.01).ConclusionSubcutaneous infection with pathogenic leptospires could cause acute death or chronic leptospirosis in hamsters after surviving the acute phase. We suggest that the renal distribution of leptospires during the acute phase probably affected the extent of tubular atrophy, leading to CKD. 相似文献
643.
Midori Tuda 《Population Ecology》1998,40(3):293-299
In an insect host (the cowpea weevilCallosobruchus maculatus)- parasitoidHeterospilus prosopidis) experimental system, the population densities of the component species oscillated for the first 20 generations and then
abruptly stabilized as the parasitoid density decreased. Examination of the host and parasitoid after the 40th generation
in the long-term experiment showed that (1) host larvae exhibited contest-type competition (killing other larvae inhabiting
the same bean), in contrast to the founder population being scramble-type competitors and (2) the parasitoid attack rate on
the host did not change. There was also an evolutionary trade-off between body size and the rates of larval survival and development,
suggesting a cost of contest competition on larval survivorship and development. I tested model predictions (Tuda and Iwasa
1998) that (1) host equilibrium population size should gradually decrease as the proportion of the contest type increases
and that (2) random attacks of the parasitoid on the host should reduce the rate of increase in proportion of the contest
type, and the effect should become manifest especially during the first 20 generations. Two of three host-only replicates
showed significant decrease in population sizes. Although the density of emerging adults per bean did not differ between replicates
of the host-only and host-parasitoid systems, comparison of the host body size between them on day 270 (at the 13th generation)
showed that the host was more contest-type in the host-only system than in the host-parasitoid system, as the model predicted,
and later on day 650 the effect of the parasitoid had disappeared. 相似文献
644.
645.
DNase was extracted and purified about 1,000-fold from the myceliaof a phyto-pathogenic fungus, Monilinia fructicola. The DNasewas an endonucleolytic enzyme and digested both native and heat-denaturedDNAs into oligonucleotides having 5'-phosphoryl and 3'-hydroxyltermini. The DNase required Mg ions for full activity. The isoelectricpoint of this enzyme was 9.0, and the molecular weight was about36,000 daltons. (Received January 18, 1980; ) 相似文献
646.
Characterization of fucosyl glycopeptides from cell surface and cellular material of rat fibroblasts
Takashi Muramatsu Midori Ogata Norio Koide 《Biochimica et Biophysica Acta (BBA)/General Subjects》1976,444(1):53-68
Approximately 70% of fucose-labeled glycopeptides from the cell surface and cellular material of rat fibroblasts (3Y1B cells) were hydrolyzed by endo-β-N-acetylglucosaminidase D in the presence of neuraminidase, β-glactosidase and β-N-acetylglucosaminidase. Structure of the suspceptible glycopeptides were found to be very similar to non-membrane glycopeptides of the complex heteropolysaccharide unit, such as the sialylated glycopeptides of thyroglobulin. On the other hand, the resistant glycopeptides were also refractory toward endo-β-N-acethylglucosaminidase H and α-mannosidase, and appeared to be a mixture of glycopeptides with unique structures. 相似文献
647.
648.
Fujimoto Keisaku Ura Midori Yamazaki Haruna Uematsu Akikazu 《Sleep and biological rhythms》2018,16(3):323-330
Sleep and Biological Rhythms - The purpose was to determine whether the instability of parasympathetic nerve (PN) function is associated with fragmentation of sleep and the instability can be... 相似文献
649.
Sawano Hikaru Matsuzaki Takuma Usui Tomoyuki Tabara Midori Fukudome Akihito Kanaya Akihiro Tanoue Daichi Hiraguri Akihiro Horiguchi Gorou Ohtani Misato Demura Taku Kozaki Toshinori Ishii Kazuo Moriyama Hiromitsu Fukuhara Toshiyuki 《Journal of plant research》2017,130(1):45-55
Journal of Plant Research - The model plant Arabidopsis thaliana has five double-stranded RNA-binding proteins (DRB1-DRB5), two of which, DRB1 and DRB4, are well characterized. In contrast, the... 相似文献
650.
Although females of Ceratina flavipes are believed to be inseminated in spring on Honshu Island, Japan, 100% of the females were inseminated before hibernation on Ishikari Coast, northernmost Japan. Because most, if not all, of the males also overwintered with the females, this prehibernal insemination may be a local event. In the hibernal season, females were more frequently alone in nests than males, whereas the sex ratio in their main habitat was almost 1:1, suggesting that prehibernal dispersal is more frequent in females, but that the dispersal distance is shorter than previously reported. 相似文献