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1.
Isolation of native DNA fragments containing structural genes at the beginning, in the middle or at the end of the coding strand. 下载免费PDF全文
A method for the isolation of the DNA fragments containing structural genes at the beginning, in the middle and at the end of the coding strand is described. It involves mechanical or enzymatic shearing, exonuclease treatment, hybridization with mRNA and subsequent retention of DNA-mRNA complex on poly(U)-Sepharose. Hybridization of the DNA fragments with mRNA takes place with high specificity and isolated material is enriched in structural genes. Applications of this method for gene isolation are discussed. 相似文献
2.
Asadulghani Nitta K Kaneko Y Kojima K Fukuzawa H Kosaka H Nakamoto H 《Archives of microbiology》2004,182(6):487-497
3.
Takashi Kitagawa Shingo Kimura Hideaki Nakata Harumi Yamada Akira Nitta Yoshikazu Sasai Hideharu Sasaki 《Environmental Biology of Fishes》2009,84(2):193-196
The habitat and movements of a Pacific bluefin tuna were investigated by reanalyzing archival tag data with sea surface temperature
data. During its trans-Pacific migration to the eastern Pacific, the fish took a direct path and primarily utilized waters,
in the Subarctic Frontal Zone (SFZ). Mean ambient temperature during the trans-Pacific migration was 14.5 ± 2.9 (°C ± SD),
which is significantly colder than the waters typically inhabited by bluefin tuna in their primary feeding grounds in the
western and eastern Pacific (17.6 ± 2.1). The fish moved rapidly through the colder water, and the heat produced during swimming
and the thermoconservation ability of bluefin tuna likely enabled it to migrate through the cold waters of the SFZ. 相似文献
4.
Calcium binding lysozyme from pigeon egg-white was crystallized by the hanging drop vapor diffusion technique using ammonium sulphate as a precipitant. The crystals belong to the orthorhombic system, space group P2(1)2(1)2(1), and have unit cell dimensions of a = 34.2 A, b = 34.8 A, and c = 99.4 A. One asymmetric unit contains one molecule of the pigeon lysozyme. The crystals diffract X-rays at least to 2.0 A resolution and are suitable for high resolution structure analysis. The diffraction data up to 3.0 A resolution were collected with a diffraction image processor, DIP100, using a Fuji imaging plate as an area detector. The structure was solved by the molecular replacement technique and refined to an R factor of 0.216. Least-squares fitting of the main-chains of pigeon egg-white lysozyme with those of chicken egg-white lysozyme and baboon alpha-lactalbumin showed that the main-chain folding of pigeon lysozyme is more similar to that of chicken lysozyme than that of alpha-lactalbumin. The largest differences between the pigeon and chicken lysozymes are in the surface loop regions. 相似文献
5.
N. Nitta M. L. Farman S. A. Leong 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,95(1-2):20-32
A high-density genetic map of the rice blast fungus Magnaporthe grisea (Guy11×2539) was constructed by adding 87 cosmid-derived RFLP markers to previously generated maps. The new map consists
of 203 markers representing 132 independently segregating loci and spans approximately 900 cM with an average resolution of
4.5 cM. Mapping of 33 cosmid probes from the genetic map generated by Sweigard et al. has allowed the integration of two M. grisea maps. The integrated map showed that the linear order of markers along all seven chromosomes in both maps is in good agreement.
Thirty of eighty seven markers were derived from cosmid clones that contained the retrotransposon MAGGY (M. grisea gypsy element). Mapping of single-copy DNA sequences associated with the MAGGY cosmids indicated that MAGGY elements are
scattered throughout the fungal genome. In eight cases, the probes associated with MAGGY elements showed abnormal segregation
patterns. This suggests that MAGGY may be involved in genomic rearrangements. Two RFLP probes linked to MAGGY elements, and
another flanking other repetitive DNA elements, identified sequences that were duplicated in the Guy11 genome. Most of the
MAGGY cosmids also contained other classes of repetitive DNA suggesting that repetitive DNA sequences tend to cluster in the
M. grisea genome.
Received: 17 February 1997 / Accepted: 21 February 1997 相似文献
6.
Yu Yokoyama Masaki Tanito Koji Nitta Maki Katai Yasushi Kitaoka Kazuko Omodaka Satoru Tsuda Toshiaki Nakagawa Toru Nakazawa 《PloS one》2014,9(6)
PurposeThe Glaucoma Stereo Analysis Study (GSAS), a cross sectional multicenter collaborative study, used a stereo fundus camera to assess various morphological parameters of the optic nerve head (ONH) in glaucoma patients and investigated the relationships between these parameters and patient characteristics.ResultsPatient characteristics included refractive error of −3.38±3.75 diopters, intraocular pressure (IOP) of 13.6±2.6 mmHg, and visual field mean deviation (MD) of −4.71±3.26 dB. Representative ONH parameters included a horizontal disc width of 1.66±0.28 mm, vertical disc width of 1.86±0.23 mm, disc area of 2.42±0.63 mm2, cup area of 1.45±0.57 mm2, and cup volume of 0.31±0.22 mm3. Correlation analysis revealed significant negative associations between vertical cup-to-disc ratio (0.82±0.08) and MD (r = −0.40, P<0.01) and between disc tilt angle (10.5±12.5 degrees) and refractive error (r = −0.36, P<0.01). Seventy-five percent of the eyes had a positive value for rim decentering (0.30±0.42), indicating that rim thinning manifested more often as an inferior lesion than a superior lesion.ConclusionWe used stereoscopic analysis to establish a database of ONH parameters, which may facilitate future studies of glaucomatous changes in ONH morphology. 相似文献
7.
8.
Itani Osamu Kaneita Yoshitaka Jike Maki Furuya Misaki Uezono Chizuru Oda Fusako Agematsu Ryuji Tokiya Mikiko Otsuka Yuichiro Ohida Takashi 《Sleep and biological rhythms》2018,16(2):239-251
Sleep and Biological Rhythms - This study was conducted to investigate the association between industrial accidents and sleep-related parameters in factory workers, and to examine the effectiveness... 相似文献
9.
Quantitative analysis of DNA-porphyrin interactions 总被引:1,自引:0,他引:1
The binding of manganese(III)-tetra(4-N-methylpyridyl)porphyrin (MnTMpyP) with synthetic poly(dA-dT)2, poly(dI-dC)2, and poly(dG-dC)2 DNAs as well as calf thymus (CT) DNA has been quantitatively studied in detail using induced CD (circular dichroism) spectroscopy in the Soret absorption band. The CD spectra, which changed greatly depending on the porphyrin to DNA base-pair molar ratio (r), were normalized with respect to DNA concentration and deconvoluted. Three independent component binding modes (named mode 1, 2, and 3 in the order of increasing r values) were identified, which successfully simulated the observed CD spectra with negligibly small residuals for a wide range of r values. In the case of poly(dA-dT)2, poly (dI-dC)2, and CT DNA, all the three modes appeared, whereas in the case of poly(dG-dC)2 DNA, only modes 1 and 3 appeared in the r range studied. The r dependence of each binding mode, i.e., its relative affinity toward DNA, has been revealed by this analysis. Mode 1, which appeared as a single binding mode at very low r values (r < or = ca. 0.05), was inhibited by the addition of methyl green, a drug that preferentially binds to the major groove of poly (dA-dT)2 DNA. Berenil, a known minor groove binder to poly(dA-dT)2 or poly(dI-dC)2 DNA, inhibited modes 2 and 3. From these inhibition experiments as well as comparison of the component spectra for DNAs of different sequence, a binding site on DNA was proposed for each component binding mode. The number of DNA base pairs covered by a single molecule of porphyrin was estimated. 相似文献
10.
Tetsuro Tamaki Yoshiyasu Uchiyama Yoshinori Okada Kayoko Tono Masahiro Nitta Akio Hoshi Akira Akatsuka 《Histochemistry and cell biology》2009,132(1):59-70
Tissue inflammation and multiple cellular responses in the compensatory enlarged plantaris (OP Plt) muscle induced by surgical
ablation of synergistic muscles (soleus and gastrocnemius) were followed over 10 weeks after surgery. Contralateral surgery
was performed in adult Wistar male rats. Cellular responses in muscle fibers, blood vessels and nerve fibers were analyzed
by immunohistochemistry and electron microscopy. Severe muscle fiber damage and disappearance of capillaries associated with
apparent tissue edema were observed in the peripheral portion of OP Plt muscles during the first week, whereas central portions
were relatively preserved. Marked cell activation/proliferation was also mainly observed in peripheral portions. Similarly,
activated myogenic cells were seen not only inside but also outside of muscle fibers. The former were likely satellite cells
and the latter may be interstitial myogenic cells. One week after surgery, small muscle fibers, small arteries and capillaries
and several branched-muscle fibers were evident in the periphery, thus indicating new muscle fiber and blood vessel formation.
Proliferating cells were also detected in the nerve bundles in the Schwann cell position. These results indicate that the
compensatory stimulated/enlarged muscle is a suitable model for analyzing multiple physiological cellular responses in muscle–nerve–blood
vessel units under continuous stretch stimulation.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献