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81.
82.
Studies on DNA markers (D4S10 and D4S43/S127) genetically linked to Huntington's disease in Japanese families 总被引:1,自引:0,他引:1
Ichiro Kanazawa Ikuko Kondo Joh-E Ikeda Teruaki Ikeda Yuichior Shizu Mitsuo Yoshida Hirotaro Narabayashi Shigetoshi Kuroda Hisayuki Tsunoda Eiji Mizuta Yoko Okuno Kiyotaka Sugawara Miho Murata Mafuyu Takahashi James F. Gusella 《Human genetics》1990,85(3):257-260
Summary This is the first full report on the genetic linkage between Japanese Huntington's disease and the DNA markers D4S10 and D4S43/S127. With use of the HindIII, BglI, and EcoRI polymorphisms detected at D4S10, and the combination of all these polymorphisms to give composite haplotypes, nine Japanese Huntington's disease families were found to be informative. Three recombinants for D4S10 were detected in these families, giving a maximum lod score of 1.662 at a of 0.10. Similarly, when we used the MspI and PvuII polymorphisms detected by D4S43/S127, five families gave informative results. No recombinant was detected in these families, giving a maximum lod score of 3.348 at a of 0.00. These results clearly support the view that the Japanese Huntington's disease gene may be identical with the Western gene, in spite of the lower prevalence rate in Japan. 相似文献
83.
Reproductive compensation of a perennial plant Sanguisorba tenuifolia to herbivory by Phengaris teleius 下载免费PDF全文
Plants that are consumed by herbivores incur a reduction in fitness. Therefore, plants need to prepare to defend against and/or avoid herbivory using ‘resistance’ and/or ‘tolerance’ systems. Phengaris teleius is a specialist herbivore of Sanguisorba tenuifolia. Phengaris teleius lays eggs in the flower buds of S. tenuifolia and the larvae of P. teleius feed on the ovaries and ovules of S. tenuifolia. In order to clarify the extent of herbivory damage by P. teleius and effect on reproduction in S. tenuifolia, we conducted field observations and artificial cutting experiments carried out in the natural habitat where both P. teleius and S. tenuifolia live sympatrically. Phengaris teleius often lays one egg per spike, and about half of the total eggs were laid on the spike that developed at the shoot apex and was largest in size. The fruits were damaged most heavily in the spike in which an egg was laid. However, the number of fruits was almost the same between individuals with no damage and individuals with a feeding damage rate of 40% or less. This showed that compensation would be achieved by increasing the number of fruits in other spikes without damage. On the other hand, because no compensation was detected in the cutting experiments, it was considered that compensation may be induced by biological stimuli produced by P. teleius. These responses may be one of the mechanisms for continuing the interspecific relationship between S. tenuifolia (host plant) and P. teleius (herbivore insect). 相似文献
84.
Makoto Kiso Mitsuru Maeda Norio Kurihara Minoru Nakajima 《Bioscience, biotechnology, and biochemistry》2013,77(2):459-461
Meso-(1245/36)-1,2,4,5,6-pentachloro-3-methylthiocyclohexane, and (124/356)-1,2,4,5,6-pentachloro-3-methylthio and ethylthiocyclohexanes were prepared from (1234/56)-1,4,5,6-tetrachloro-2,3-epoxycyclohexane (α-BTC cis-epoxide). 相似文献
85.
Naoyuki Miyashita Yoshifumi Kubota Masashi Kimura Masamitsu Nakajima Yoshihito Niki Rinzo Soejima Akira Matsumoto 《Microbiology and immunology》1994,38(11):857-864
The isolation of Chlamydia pneumoniae, especially from elderly persons, is generally not easy. Recently, we succeeded in isolating a chlamydial strain, which was designated KKpn-15, from a 57-year-old man suffering from acute bronchitis. It was compared with well established strains of C. pneumoniae, C. trachomatis and C. psittaci, and its biological properties, such as the morphology of elementary bodies (EBs) and inclusions, and the immunochemistry of EB proteins, were investigated. Based on the results obtained in the present study, it was confirmed that the new chlamydial strain, KKpn-15, is a member of the C. pneumoniae strain and that the organisms of KKpn-15 are useful as an antigen for the serodiagnosis and epidemiology of C. pneumoniae infection. 相似文献
86.
Toshio Fujita Hiroshi Deura Mitsugi Senda Toshimichi Ikegami Minoru Nakajima 《Bioscience, biotechnology, and biochemistry》2013,77(8):1192-1197
The kinetics of decomposition of the 3-substituted-phenyl-1-nitroso-1-methylureas was studied under a certain pH and various temperatures. It was observed that the rate of decomposition is first order in concentration of the nitroso compound under the constant pH and that the more the electron withdrawal of the ring substituent, the larger is the rate of decomposition. From the temperature dependence of the rate, the apparent enthalpy and entropy of activation were determined. The sequence of the rate of decomposition of this series of compounds was found to be governed largely by the variation of the entropy rather than that of the enthalpy of activation. 相似文献
87.
Solution conformation of endothelin determined by means of 1H-NMR spectroscopy and distance geometry calculations 总被引:4,自引:0,他引:4
H Tamaoki Y Kobayashi S Nishimura T Ohkubo Y Kyogoku K Nakajima S Kumagaye T Kimura S Sakakibara 《Protein engineering》1991,4(5):509-518
The structure of endothelin-1 (ET-1), an endothelial cell-derived peptide with vasoconstricting activity, was determined in an aqueous solution by means of a combination of NMR and distance geometry calculations. The resulting structure is characterized by an alpha-helical conformation in the sequence region, Lys9-Cys15. Furthermore, an extended structure and a turn structure exist in the Cys1-Ser4 and Ser5-Asp8 regions respectively, and no preferred conformation was found for the C-terminal part of the peptide which was not uniquely constrained by the NMR data. These structural elements, the alpha-helical structure in the sequence portion, Cys-X-X-X-Cys, and the extended structure in Cys-X-Cys, are homologous to those found commonly in several neurotoxic peptides. 相似文献
88.
89.
Yoko Yokoyama Naoki Kakudate Futoshi Sumida Yuki Matsumoto Gregg H. Gilbert Valeria V. Gordan 《PloS one》2013,8(3)
Background
Dental caries are largely preventable, and epidemiological evidence for a relationship between diet and oral health is abundant. To date, however, dentists’ perceptions about the role of diet and dentists’ practice patterns regarding diet counseling have not been clarified.Objective
The purposes of this study were to: (1) examine discordance between dentists’ perception of the importance of diet in caries treatment planning and their actual provision of diet counseling to patients, and (2) identify dentists’ characteristics associated with their provision of diet counseling.Design
The study used a cross-sectional study design consisting of a questionnaire survey in Japan.Participants
The study queried dentists working in outpatient dental practices who were affiliated with the Dental Practice-Based Research Network Japan (JDPBRN), which aims to allow dentists to investigate research questions and share experiences and expertise (n = 282).Measurement
Dentists were asked about their perceptions on the importance of diet and their practice patterns regarding diet counseling, as well as patient, practice, and dentist background data.Results
The majority of participants (n = 116, 63%) recognized that diet is “more important” to oral health. However, among participants who think diet is “more important” (n = 116), only 48% (n = 56) provide diet counseling to more than 20% of their patients. Multiple logistic regression analysis suggested that several variables were associated with providing diet counseling; dentist gender, practice busyness, percentage of patients interested in caries prevention, caries risk assessment, and percentage of patients who receive blood pressure screening.Conclusions
Some discordance exists between dentists’ perception of the importance of diet in caries treatment planning and their actual practice pattern regarding diet counseling to patients. Reducing this discordance may require additional dentist education, including nutritional and systemic disease concepts; patient education to increase perception of the importance of caries prevention; or removing barriers to practices’ implementation of counseling.Trial Registration
ClinicalTrials.gov NCT01680848相似文献90.
Takashi Nobusawa Yoko Okushima Noriko Nagata Mikiko Kojima Hitoshi Sakakibara Masaaki Umeda 《PLoS biology》2013,11(4)
Plant organ growth is controlled by inter-cell-layer communication, which thus determines the overall size of the organism. The epidermal layer interfaces with the environment and participates in both driving and restricting growth via inter-cell-layer communication. However, it remains unknown whether the epidermis can send signals to internal tissue to limit cell proliferation in determinate growth. Very-long-chain fatty acids (VLCFAs) are synthesized in the epidermis and used in the formation of cuticular wax. Here we found that VLCFA synthesis in the epidermis is essential for proper development of Arabidopsis thaliana. Wild-type plants treated with a VLCFA synthesis inhibitor and pasticcino mutants with defects in VLCFA synthesis exhibited overproliferation of cells in the vasculature or in the rib zone of shoot apices. The decrease of VLCFA content increased the expression of IPT3, a key determinant of cytokinin biosynthesis in the vasculature, and, indeed, elevated cytokinin levels. These phenotypes were suppressed in ipt3;5;7 triple mutants, and also by vasculature-specific expression of cytokinin oxidase, which degrades active forms of cytokinin. Our results imply that VLCFA synthesis in the epidermis is required to suppress cytokinin biosynthesis in the vasculature, thus fine-tuning cell division activity in internal tissue, and therefore that shoot growth is controlled by the interaction between the surface (epidermis) and the axis (vasculature) of the plant body. 相似文献