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991.
Igaki Michihito Suzuki Masahiro Sakamoto Ichiro Ichiba Tomohisa Kuriyama Kenichi Uchiyama Makoto 《Sleep and biological rhythms》2018,16(1):77-84
Sleep and Biological Rhythms - Appropriate warming of the periocular or posterior cervical skin has been reported to induce autonomic or mental relaxation in humans. To clarify the effects of... 相似文献
992.
Ichiro Tamaki Katsushige Nomura Reiko Nomura Chieko Tate Chikara Watanabe Yoshihiro Miyakami Yumiko Yabe 《Landscape and Ecological Engineering》2018,14(2):269-276
Magnolia stellata is a rare subcanopy tree species that grows in secondary forests in warm temperate zones. It is now endangered due to habitat degradation by vegetation succession. In an attempt to improve the habitat, a 30 m?×?10 m plot (0.03 ha) was set up with all vegetation including M. stellata being clear-cut in January 2012. The number of sprouts increased for 1–2 years after clear-cutting and then gradually decreased or remained constant. Five years after clear-cutting, the numbers of individuals and stems, and the total basal area (BA), were 87.0, 165.5 and 3.2%, respectively, of the values before clear-cutting. BA was highest for Ilex pedunculosa, followed by M. stellata and Hydrangea paniculata. Some sprouted individuals of M. stellata produced flower buds in the second year after clear-cutting, and flowered and fruited in the spring and summer of the third year, respectively. The densities of potential canopy species were 18,533 ha?1 (height >?0.5 m) and 7,267 ha?1 (height >?1.2 m), vastly exceeding the value of the criterion for successful natural regeneration after clear-cutting of warm temperate forests in the region (3,000 ha?1). Based on this criterion, it is thus considered that the natural regeneration has reached completion. However, 45.1% (height >?0.5 m) and 95.5% (height >?1.2 m) of M. stellata individuals were regenerated by sprouting. Further research is needed into how individuals, regenerated from seedlings, develop and reach sexual maturity, and how successive generations change. 相似文献
993.
Naohiko Okumura Naotaka Ishiguro Masuo Nakano Katsuya Hirai Akira Matsui Makoto Sahara 《Biochemical genetics》1996,34(5-6):179-189
Mitochondrial DNA (mtDNA) control regions from 40 Japanese wild boars were examined by direct sequencing after amplification
by PCR. From the DNA sequences obtained, we found eight haplotypes, whose differences arose via transitions. The geographical
distribution of these different haplotypes indicated that wild boar populations inhabited limited areas and that there was
some restricted gene flow between local populations. Eight mtDNA haplotypes from Eastern and Western domestic pigs and the
Ryukyu wild boar were also analyzed as references to those from Japanese wild boars. The cluster analyses of the control-region
sequences showed that those from Japanese wild boards belong to the Asian type as do those from Eastern domestic pigs and
the Ryukyu wild boar, which differed from the European type (Western domestic pigs). 相似文献
994.
995.
996.
Immunofluorescence staining with an antiserum raised against a presumptive meiotic histone, which has been shown to appear
prior to male meiosis in liliaceous plants, preferentially stained the centromere (kinetochore) region of meiotic chromosomes
in microsporocytes and megasporocytes. Using this antiserum, we were able clearly to visualize the centromeres at all important
meiotic stages in microsporocytes, namely, the association and fusion of centromeres of homologous chromosomes at zygotene-pachytene
in prophase I, the disjunction of the homologous centromeres at diplotene, the doubling of each centromere at metaphase I
and nonseparation of the sister centromeres at anaphase I, by confocal laser scanning microscopy. Thus, this report provides
a complete picture of the behavior of centromeres during meiosis in a eukaryote for the first time. This antiserum also decorated
centromeres during female meiosis in cryo-sectioned megasporocytes, but did not stain the centromeres of mitotic chromosomes
in root-tip meristem. From these observations, it is suggested that a meiosis-specific centromere protein is required for
the meiosis-specific behavior of the centromere.
Received: 12 May 1997; in revised form: 20 August 1997 / Accepted: 25 August 1997 相似文献
997.
998.
Disassembly and reassembly of cortical microtubules (MT) during and after segregative cell division (SCO) in Dictyosphaeria cavernosa (Forssk.) Børgesen were observed using fluorescence microscopy. Parallel cortical MT in a mother cell were intact just after the initiation of SCD, but soon circular, MT-free patches appeared. Protoplasmic contraction enlarged the patches, and in these areas, the protoplasm eventually became perforated. Long and undulating cortical MT were arranged densely in the reticulate protoplasm. During further protoplasmic contraction, cortical MT appeared to be random and decreased in density. Finally, short and random cortical MT were present in the segregated protoplasts. Parallel cortical MT reassembled in the expanding daughter cells. After the daughter cells came in contact with one another, a radial system of cortical MT was constructed at the side that faced the inside of the mother cell wall. A microtubule inhibitor (amiprophos methyl, APM) had no effect on SCO. Segregative cell division was not induced directly by mechanical wounding. A comparison between SCO and wound-induced protoplasmic contraction was made. 相似文献
999.
Ichiro Ono Keizo Matsuda Sachiko Kanno 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1996,678(2):384
A column-switching high-performance liquid chromatography method with ultraviolet detection at 210 nm has been developed for the determination of N-(trans-4-isopropylcyclohexylcarbonyl)-d-phenylalanine (AY4166, I) in human plasma. Plasma samples were prepared by solid-phase extraction with Sep-Pak Light tC18, followed by HPLC. The calibration graph for I was linear in the range 0.1–20 μg/ml. The limit of quantitation of I, in plasma, was 0.05 μg/ml. The recovery of spiked I (0.5 μg/ml) to drug-free plasma was over 92% and the relative standard deviation of spiked I (0.5 μg/ml) compared to drug-free plasma was 4.3% (n = 8). 相似文献
1000.
High-cell-density cultivations of Escherichia coli K12 in a dialysis reactor with controlled levels of dissolved oxygen were carried out with different carbon sources: glucose
and glycerol. Extremely high cell concentrations of 190 g/l and 180 g/l dry cell weight were obtained in glucose medium and
in glycerol medium respectively. Different behaviour was observed in the formation of acetic acid in these cultivations. In
glucose medium, acetic acid was formed during the earlier phase of cultivation. However, in glycerol medium, acetic acid formation
started later and was particularly rapid at the end of the cultivation. In order to estimate the influence of acetic acid
during these high-cell-density cultivations, the inhibitory effect of acetic acid on cell growth was investigated under different
culture conditions. It was found that the inhibition of cell growth by acetic acid in the fermentor was much less than that
in a shaker culture. On the basis of the results obtained in these investigations of the inhibitory effect of acetic acid,
and the mathematical predictions of cell growth in a dialysis reactor, the influence of acetic acid on high-cell-density cultivation
is discussed.
Received: 20 May 1997 / Received revision: 12 August 1997 / Accepted: 25 August 1997 相似文献