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31.
Kasuya E 《Animal behaviour》2000,59(3):629-632
When fitness decreases with increasing density in a habitat, dispersal behaviour is expected to evolve. To avoid competition between kin, dispersal behaviour based on kin recognition should be more likely to occur when the individuals in a habitat are closely related. I tested this prediction with first-instar larvae (crawlers) of the mango shield scale, Milviscutulus mangiferae. The body size of adult females, a measure of fecundity, was larger when only one female was present on a leaf than when two were present. When I placed two crawlers on a leaf, they emigrated more frequently when they were siblings than when they were not related. I discuss the implication of the results for kin recognition in thelytokous parthenogenetic animals. Copyright 2000 The Association for the Study of Animal Behaviour. 相似文献
32.
Fujimori A Hashimoto H Araki R Saito T Sato S Kasama Y Tsutsumi Y Mori M Fukumura R Ohhata T Tatsumi K Abe M 《Radiation research》2002,157(3):298-305
The catalytic subunit of DNA-dependent protein kinase plays critical roles in nonhomologous end joining in repair of DNA double-strand breaks and V(D)J recombination. In addition to the SCID phenotype, it has been suggested that the molecule contributes to the polymorphic variations in radiosensitivity and susceptibility to cancer in mouse strains. Here we show the nucleotide sequence of approximately 193-kbp and 84-kbp genomic regions encoding the entire Prkdc gene (also known as DNA-PKcs) in the mouse and chicken, respectively. A large retroposon was found in intron 51 in the mouse but not in the human or chicken. Comparative analyses of the genome strongly suggested that the region contains only two genes for Prkdc and Mcm4; however, several conserved sequences and cis elements were also predicted. 相似文献
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34.
Zhuo Wu Osamu Matsui Azusa Kitao Kazuto Kozaka Wataru Koda Satoshi Kobayashi Yasuji Ryu Tetsuya Minami Junichiro Sanada Toshifumi Gabata 《PloS one》2015,10(3)
Purpose
To assess the feasibility of texture analysis for classifying fibrosis stage and necroinflammatory activity grade in patients with chronic hepatitis C on T2-weighted (T2W), T1-weighted (T1W) and Gd-EOB-DTPA-enhanced hepatocyte-phase (EOB-HP) imaging.Materials and methods
From April 2008 to June 2012, MR images from 123 patients with pathologically proven chronic hepatitis C were retrospectively analyzed. Texture parameters derived from histogram, gradient, run-length matrix, co-occurrence matrix, autoregressive model and wavelet transform methods were estimated with imaging software. Fisher, probability of classification error and average correlation, and mutual information coefficients were used to extract subsets of optimized texture features. Linear discriminant analysis in combination with 1-nearest neighbor classifier (LDA/1-NN) was used for lesion classification. In compliance with the software requirement, classification was performed based on datasets from all patients, the patient group with necroinflammatory activity grade 1, and that with fibrosis stage 4, respectively.Results
Based on all patient dataset, LDA/1-NN produced misclassification rates of 28.46%, 35.77% and 20.33% for fibrosis staging and 34.15%, 25.20% and 28.46% for necroinflammatory activity grading in T2W, T1W and EOB-HP images. In the patient group with necroinflammatory activity grade 1, LDA/1-NN yielded misclassification rates of 5.00%, 0% and 12.50% for fibrosis staging in T2W, T1W and EOB-HP images respectively. In the patient group with fibrosis stage 4, LDA/1-NN yielded misclassification rates of 5.88%, 12.94% and 11.76% for necroinflammatory activity grading in T2W, T1W and EOB-HP images respectively.Conclusion
Texture quantitative parameters of MR images facilitate classification of the fibrosis stage as well as necroinflammatory activity grade in chronic hepatitis C, especially after categorizing the input dataset according to the activity or fibrosis degree in order to remove the interference between the fibrosis stage and necroinflammatory activity grade on texture features. 相似文献35.
Ryutaro Kakinuma Noriyuki Moriyama Yukio Muramatsu Shiho Gomi Masahiro Suzuki Hirobumi Nagasawa Masahiko Kusumoto Tomohiko Aso Yoshihisa Muramatsu Takaaki Tsuchida Koji Tsuta Akiko Miyagi Maeshima Naobumi Tochigi Shun-ichi Watanabe Naoki Sugihara Shinsuke Tsukagoshi Yasuo Saito Masahiro Kazama Kazuto Ashizawa Kazuo Awai Osamu Honda Hiroyuki Ishikawa Naoya Koizumi Daisuke Komoto Hiroshi Moriya Seitaro Oda Yasuji Oshiro Masahiro Yanagawa Noriyuki Tomiyama Hisao Asamura 《PloS one》2015,10(12)
36.
37.
Yukari Ohta Madoka Katsumata Kanako Kurosawa Yoshihiro Takaki Hiroshi Nishimura Takashi Watanabe Ken-ichi Kasuya 《Environmental microbiology》2021,23(8):4151-4167
Microbial decomposition of allochthonous plant components imported into the aquatic environment is one of the vital steps of the carbon cycle on earth. To expand the knowledge of the biodegradation of complex plant materials in aquatic environments, we recovered a sunken wood from the bottom of Otsuchi Bay, situated in northeastern Japan in 2012. We isolated Sphingobium with high ferulic acid esterase activity. The strain, designated as OW59, grew on various aromatic compounds and sugars, occurring naturally in terrestrial plants. A genomic study of the strain suggested its role in degrading hemicelluloses. We identified a gene encoding a non-secretory tannase-family α/β hydrolase, which exhibited ferulic acid esterase activity. This enzyme shares the consensus catalytic triad (Ser-His-Asp) within the tannase family block X in the ESTHER database. The molecules, which had the same calculated elemental compositions, were produced consistently in both the enzymatic and microbial degradation of rice straw crude extracts. The non-secretory tannase-family α/β hydrolase activity may confer an important phenotypic feature on the strain to accelerate plant biomass degradation. Our study provides insights into the underlying biodegradation process of terrestrial plant polymers in aquatic environments. 相似文献
38.
Meimuna opalifera males emit extremely complex calling songs, with the main section comprising two parts. To investigate whether these two parts of the calling song have different meanings for the receivers, we conducted playback experiments. We counted and compared the number of response calls when different types of sound stimuli were presented under laboratory conditions. Meimuna opalifera males emitted significantly greater response calls during the playback of stimuli containing the former part of the songs than those containing the latter part only. This suggests that M. opalifera males tend to respond by detecting characteristics in the former part of the songs. Because the peak frequencies were similar between the former and the latter parts, the temporal patterns of the songs might be important in short-range communication between males of M. opalifera. 相似文献
39.
Shibata H Hanazono Y Ageyama N Nagashima T Ueda Y Hasegawa M Ozawa K Yoshikawa Y Terao K 《American journal of primatology》2003,61(1):3-12
Previous studies have shown that hematopoietic progenitor cells can be isolated from human or nonhuman primate bone marrow (BM) cells. In the present study, we studied the cross-reactivity of 13 anti-human CD34, two anti-human c-Kit, and one anti-human CD133 monoclonal antibodies (mAbs) with cynomolgus macaque (Macaca fascicularis) BM cells, using flow cytometric analysis, cell enrichment, and clonogenic assay. Among the 13 anti-human CD34 mAbs assessed, six cross-reacted as previously reported by other groups. However, only three of these six mAbs (clones 561, 563, and 12.8) recognized cynomolgus CD34+ cells that formed progenitor colonies when grown in methylcellulose culture. Similarly, of the two anti-human c-Kit mAbs (clones NU-c-kit and 95C3) that were previously reported to cross-react with cynomolgus BM cells, only one (clone NU-c-kit) resulted in a similar outcome. The anti-human CD133 mAb (clone AC133) also cross-reacted with cynomolgus BM cells, although these cells did not give rise to colonies when grown in culture. These results suggest that antibodies that cross-react with nonhuman primate cells may not identify the hematopoietic cells of interest. In addition, while the CD34 mAb (clone 561) results in the selection of hematopoietic progenitor cells of all lineages when assessed in methylcellulose culture, the c-Kit(high) fraction (NU-c-kit) exclusively identifies erythroid-specific progenitor cells after growth in culture. It is important to consider these findings when selecting cross-reacting mAbs to identify cells of hematopoietic lineages in macaque species. 相似文献
40.
Kobari Toru; Ikeda Tsutomu; Kanno Yasuji; Shiga Naonobu; Takagi Shogo; Azumaya Tomonori 《Journal of plankton research》2003,25(5):483-494
As the integral components of zooplankton in the subarctic NorthPacific, the three Neocalanus species (N. cristatus, N. plumchrusand N. flemingeri) are characterized by an annual life cycleand rapid development in the surface layer during springsummer.Patterns of interannual variation of abundance and body sizeof these Neocalanus species were analyzed using the time-seriesdata collected during the summers of 19791998 (20 years)at stations along the longitudinal transect line in the centralNorth Pacific, crossing five sub-areas (Alaska Current System,Subarctic Current System, Northern Transition Domain, SouthernTransition Domain and Subtropical Current System). In the southernsub-areas, quasi-decadal oscillation was observed for the 3-yearrunning mean of abundance and prosome length for copepoditestage 5 (C5) of the three Neocalanus species. Although the oscillationsignal diminished towards northern waters, it showed a positivephase during the early 1980s and 1990s and a negative phaseduring the late 1980s. In the northern waters, a biennial patternwas pronounced for anomalies of C5 prosome length for N. plumchrusand N. flemingeri, which was large in odd years and small ineven years. Significantly positive covariations among the threespecies were found for both abundance and prosome length aroundmid-latitude, where they were abundant. In the correlation analysis,these observed yearly patterns showed a statistically insignificantcorrelation with most environmental (integrated mean temperaturein surface waters, water column stability and chlorophyll aconcentration) or climatological (North Pacific Index and SouthernOscillation Index) variables. The regional difference of theoscillation signal and the synchronized covariation among thesespecies suggest that interannual variations of their abundanceand body size are mediated by common environmental force(s)with some spatial and temporal scales in the subarctic NorthPacific. 相似文献