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31.
Kumagai H Miyakawa K Negishi H Inoue H Obara K Suetsugu D 《Science (New York, N.Y.)》2003,299(5615):2058-2061
Very-long-period (VLP) signals showing simple decaying harmonic oscillations with periods near 10 seconds and lasting for about 300 seconds were observed in association with an earthquake swarm that occurred beneath Hachijo Island, Japan. Results from the source-mechanism analysis and waveform simulation based on a fluid-filled crack model consistently point to the resonance of a dike filled with a basaltic magma as the source of the VLP signals. Thus, VLP signals can be used to probe the state of the fluid and dynamic processes within a volcanic system. 相似文献
32.
Suzuki K Matsuo T Hashizume D Fueno H Tanaka K Tamao K 《Science (New York, N.Y.)》2011,331(6022):1306-1309
The cyclobutadiene (CBD) molecule C(4)H(4) deviates from a high-symmetry square geometry to compensate for its antiaromatic electronic structure. Here, we report a CBD silicon analog, Si(4)(EMind)(4) (1), stabilized by the bulky 1,1,7,7-tetraethyl-3,3,5,5-tetramethyl-s-hydrindacen-4-yl (EMind) groups, obtained as air- and moisture-sensitive orange crystals by the reduction of (EMind)SiBr(3) with three equivalents of lithium naphthalenide. X-ray crystallography reveals a planar and rhombic structure of the Si(4) four-membered ring, with alternating pyramidal and planar configurations at the silicon atoms. The large (29)Si chemical shift differences (Δδ > 350 parts per million) in the solid-state nuclear magnetic resonance spectra suggest a contribution of an alternately charge-separated structure. The rhombic-shaped charge-separated singlet state of compound 1 thus stabilizes its cyclic 4π-electron antiaromaticity in a manner that contrasts sharply with the bond-length alternation, characterizing the rectangular distortion of carbon-based CBD. 相似文献
33.
Yuko MATSUBARA Takahiroi TAGAMI Daisuke MATSUNAGA Akiko SANO Kimiaki MARUYAMA 《Animal Science Journal》2011,82(3):428-433
In our continuing effort to generate transgenic chickens, sonoporation was chosen to insert an exogenous gene into the chicken genome. An EGFP expression vector (pCAG‐EGFPac) and microbubbles were injected into the central disc of stage‐X blastoderm or the germinal crescent of stage‐4 embryos, followed by ultrasonic vibration. Nineteen chicks out of 108 treated embryos hatched, six females and six males out of these 19 chicks grew to sexual maturity and two females and three males lived for 3 years. Genomic DNA from 17 out of 35 gonads from embryos and chicks that died before sexual maturity was EGFP‐positive by PCR. No EGFP sequence was detected in the genomic DNA of 322 embryos from six sexually mature females and the semen from four sexually mature males by PCR. When genomic DNA was obtained from various tissues of five 3‐year‐old chickens, the EGFP sequence was amplified from the genomic DNA of the breast muscle of a female (No. 85). The above sequence was subjected to DNA sequencing and verified to be the EGFP sequence. These results showed that sonoporation is an effective tool for the transduction of exogenous genes into chicken embryos for the generation of transgenic chickens. 相似文献
34.
Sato D Awad AA Chae SH Yokota T Sugimoto Y Takeuchi Y Yoneyama K 《Journal of agricultural and food chemistry》2003,51(5):1162-1168
A simple and rapid analytical method for strigolactones, germination stimulants for the root parasitic weeds witchweed (Striga spp.) and broomrape (Orobanche spp.), has been developed using high-performance liquid chromatography connected to tandem mass spectrometry (LC/MS/MS). The natural strigolactones (strigol, sorgolactone, orobanchol, and alectrol) were clearly separated and identified by LC/MS/MS. As low as 0.1 pg/microL of strigol and 0.5 pg/microL of sorgolactone could be quantified, whereas 1 pg/microL was needed for the quantification of orobanchol (S/N > 10). Using this method, it was found that red clover produces orobanchol and alectrol but not strigol. The roots of red clover seedlings were found to produce 13, 70, 58, and 65 pg of orobanchol/plant 1, 2, 3, and 4 weeks after germination, respectively. 相似文献
35.
36.
Nakanishi M Kuwamura M Yamate J Fujita D Sasai H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(9):939-941
A 6-year-old female ferret had a firm mass 2 cm in diameter in the pyloric region of the stomach. Histopathologically, the mass was composed of neoplastic proliferation of well-differentiated epithelial cells, showing tubular or glandular growth patterns. Osseous metaplastic foci were often found in the tumor. Tumor cells showed a positive reaction for immunohistochemistry against bone morphogenetic protein-6, an osteogenic factor. A diagnosis of gastric adenocarcinoma with ossification was made. 相似文献
37.
Matsuura Y Suzuki M Hayakawa D Asano M Sasaki M Kitamura N Yamada J Tsubota T Ohtaishi N 《The Japanese journal of veterinary research》2004,51(3-4):167-172
We analyzed the localization of steroidogenic enzymes (P450 scc, 3 beta HSD, P450 arom and P450 c17) in the corpora lutea of two Hokkaido sika deer (Cervus nippon yesoensis) during the early mating season. Two corpora lutea were found in each female and the timing of formation of the corpora lutea seemed different. P450 scc, and 3 beta HSD, positive luteal cells were found in both corpora lutea. The existence of two functional corpora lutea from the early mating season through pregnancy suggests that progesterone secreted by two or more corpora lutea is necessary for maintenance of pregnancy in sika deer. 相似文献
38.
Yamaji D Kitamura H Kimura K Matsushita Y Okada H Shiina T Morimatsu M Saito M 《Veterinary immunology and immunopathology》2004,98(3-4):175-184
Molecule possessing ankyrin-repeats induced by lipopolysaccharide (MAIL) is known as an IkappaB protein induced after administration of bacterial lipopolysaccharide (LPS) to mice. In the present study, we cloned bovine MAIL cDNA and examined its mRNA expression in white blood cells isolated from Holstein cows. Bovine MAIL had more than 80% amino acid identities with murine and human MAILs, highly conserved ankyrin-repeat motifs and PEST-like sequences. Bovine MAIL mRNA was undetectable in isolated peripheral white blood cells, but rapidly induced (<1h) after stimulation by LPS and lipid A in vitro in a dose-dependent manner. The lipid A-induced MAIL mRNA expression was found in polymorphonuclear cells, monocytes/macrophages and total lymphocytes, but not in T-lymphocytes. MAIL mRNA was also induced in vivo in peripheral blood leukocytes of cows after intramammary injection of Escherichia coli derived from coliform mastitis. Thus, bovine MAIL, as rodent MAILs, is induced by inflammatory stimuli in specific immune cells in vitro and in vivo, suggesting a role in inflammatory responses to bacterial infection in cattle. 相似文献
39.
40.
Yasuda D Fujita M Yasuda S Taniguchi A Miura H Hasegawa D Orima H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(11):1447-1451
We evaluated the usefulness of MRI and compared it with CT for diagnosis of mesenteric lymphoma in a dog. The results in the plain CT, dynamic CT and plain MR (T1WI and T2WI) images suggested that the mass was a large single nodular lesion with abundant blood perfusion. On enhanced MRI(T1WI) , the mass was depicted as a tumor with adhesion to the gut wall. Exploratory laparotomy confirmed the mass was consistent with the findings on enhanced MRI. We think that MRI might be a useful imaging tool for diagnosis of canine mesenteric lymphoma. 相似文献