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71.
Nakatsuji S Nambu Y Tonomura H Sakai O Jonas S Broholm C Tsunetsugu H Qiu Y Maeno Y 《Science (New York, N.Y.)》2005,309(5741):1697-1700
As liquids crystallize into solids on cooling, spins in magnets generally form periodic order. However, three decades ago, it was theoretically proposed that spins on a triangular lattice form a liquidlike disordered state at low temperatures. Whether or not a spin liquid is stabilized by geometrical frustration has remained an active point of inquiry ever since. Our thermodynamic and neutron measurements on NiGa2S4, a rare example of a two-dimensional triangular lattice antiferromagnet, demonstrate that geometrical frustration stabilizes a low-temperature spin-disordered state with coherence beyond the two-spin correlation length. Spin liquid formation may be an origin of such behavior. 相似文献
72.
Takashi?OkuEmail author Koji?Tanaka Motohiro?Iwamoto Yasuhiro?Inoue Hirokazu?Ochiai Hisatoshi?Kaku Seiji?Tsuge Kazunori?Tsuno 《Journal of General Plant Pathology》2004,70(3):159-167
The clustered hrp genes encoding the type III secretion system in the Japanese strains MAFF301237 and MAFF311018 of Xanthomonas oryzae pv. oryzae were sequenced and compared. The strains differ in their pathogenicity, location, and year of isolation. A 30-kbp sequence comprising 29 open reading frames (ORFs) was identical in its structural arrangement in both strains but differed from X. campestris pv. campestris, X. axonopodis pv. citri, and X. axonopodis pv. glycines in certain genes located between the hpaB-hrpF interspace region. The DNA sequence and the putative amino acid sequence in each ORF was also identical in both X. oryzae pv. oryzae strains as were the PIP boxes and the relative sequences. These facts clearly showed that the structure of the hrp gene cluster in X. oryzae pv. oryzae is unique. 相似文献
73.
Rumiko KODASHIMA Noriharu AE Noriko KIKKOUJI Shingo MATSUMOTO 《Soil Science and Plant Nutrition》2006,52(1):134-134
(pp. 825–831)
This study was carried out to clarify the effects of soil nitrate before cultivation and amounts of basal-dressed nitrogen on additional N application rate and yields of semi-forced tomato for three years from 1998 to 2000. The amounts and timing of additional N dressing were determined based on diagnosis of petiole sap nitrate. The top-dressing was carried out with a liquid fertilizer when the nitrate concentration of a leaflet's petiole sap of leaf beneath fruit which is 2–4 cm declined below 2000 mg L−1 .
For standard yield by the method of fertilizer application based on this condition, no basal-dressed nitrogen was required when soil nitrate before cultivation was 150 mg kg−1 dry soil or higher in the 0–30 cm layer; 38 kg ha−1 of basal-dressed nitrogen, which corresponds to 25% of the standard rate of fertilizer application of Chiba Prefecture, was optimum when soil nitrate before cultivation was 100150 mg kg−1 dry soil; 75 kg ha−1 of basal-dressed nitrogen, which corresponds to 50% of the standard, was optimum when soil nitrate before cultivation was under 100 mg kg−1 dry soil. A standard yield was secured and the rate of nitrogen fertilizer application decreased by 49–76% of the standard by keeping the nitrate concentration of tomato petiole sap between 1000–2000 mg L−1 from early harvest time to topping time under these conditions. 相似文献
This study was carried out to clarify the effects of soil nitrate before cultivation and amounts of basal-dressed nitrogen on additional N application rate and yields of semi-forced tomato for three years from 1998 to 2000. The amounts and timing of additional N dressing were determined based on diagnosis of petiole sap nitrate. The top-dressing was carried out with a liquid fertilizer when the nitrate concentration of a leaflet's petiole sap of leaf beneath fruit which is 2–4 cm declined below 2000 mg L
For standard yield by the method of fertilizer application based on this condition, no basal-dressed nitrogen was required when soil nitrate before cultivation was 150 mg kg
74.
Takahiro SATO Maki SEKIGUCHI Atsuko MATSUMOTO Kaho SHIMADA Mikuya IWANAGA Mitsutaka IKEZAWA Yasuko HANAFUSA Tomoyuki SHIBAHARA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(3):342
A 31-month-old Japanese Black cow (Bos taurus) aborted at 5 months of gestation with no clinical symptoms. Histopathological examination of the placenta and fetus revealed severe necrotic placentitis associated with numerous irregular degenerative fungi and inflammatory cells. Regular filamentous fungi were also detected, without inflammatory response in the fetal digestive and respiratory organs. Both fungi had aleurioconidia and septa in the placenta and fetal organs and immunohistochemically stained with antibodies against Aspergillus spp. Aspergillus terreus was isolated from the fetal lung and abomasal contents as confirmed using mycological and molecular methods. This is the first immunohistochemical, morphological, and molecular identification of A. terreus in bovine placenta and aborted fetuses. 相似文献
75.
The aim of this study was to evaluate the changes in plasma concentrations of estrone sulfate (E(1)S) and estradiol-17beta (E(2)beta) during the peripartum period (from day 10 prepartum to day 1 postpartum) associated with and without retention of fetal membranes (RFM) in Holstein-Friesian cattle (n=42). Plasma samples were analyzed for E(1)S and E(2)beta by ELISA. All parturitions were spontaneous and normal. Of 38 cattle delivering singletons, 29 had no RFM (singleton-normal group) and nine had RFM for more than 12 h (singleton-RFM group). Four cows gave birth to twins, and each twin had its own fetal membrane (FM). Two twinning cows expelled both FMs normally within 12 h (twin-normal group). In the remaining 2 twinning cows (twin-RFM group), the FM was expelled normally for one twin (first), while the FM of the other (second) was retained. There were no significant differences in the E(1)S concentrations or their increments from the concentrations on the preceding day between the normal and RFM groups of singleton cows on any peripartum day. The mean plasma E(2)beta concentrations on each day from day 10 to day 3 prepartum were significantly lower (P<0.05) in the singleton-RFM group compared with the singleton-normal group; however, on days 2 and 1 prepartum, the increments in the E(2)beta concentrations from the concentrations on the preceding days were significantly higher (P<0.05) in the singleton-RFM group than in the singleton-normal group. Thus, the plasma E(1)S concentrations just before parturition may not be associated with RFM. In the cows with RFM, the lower plasma E(2)beta concentrations that were found prior to day 2 prepartum may have been associated with immature placentomes, and the rapid rise in plasma E(2) beta within 1 to 2 days prior to calving may have produced asynchrony of placental and/or fetal maturation in relation to calving, thus resulting in RFM. 相似文献
76.
Noriyuki HORIUCHI Makoto KOMAGATA Keiichi SHITAMURA Shiori CHIBA Kotaro MATSUMOTO Hisashi INOKUMA Takane MATSUI Yoshiyasu KOBAYASHI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(6):729-732
An 11-year-old Holstein-Friesian cow exhibited anorexia and jaundice. A large mass was
found in the liver during necropsy. Macroscopically, the mass was composed of dark red
multilobular tissue and a centrally located abscess, which was connected to the hepatic
duct. Histologically, the mass consisted of proliferation of small neoplastic cells and
was demarcated from the hepatic parenchyma by a thick region of granulation tissue. The
neoplastic cells were predominantly arranged in solid sheets, but they also formed
blood-filled cancellous structures, and proliferating foci were seen around blood vessels.
Periodic acid-Schiff reaction demonstrated that a fine basement membrane-like structure
surrounded the neoplastic cells. Immunohistochemically, the neoplastic cells were positive
for vimentin and alpha smooth muscle actin and negative for cytokeratin, factor
VIII-related antigen, chromogranin and desmin. Based on its histopathological features,
the hepatic neoplasm was diagnosed as a primary glomus tumor. This is the first report
about a primary glomus tumor of the liver in a cow. 相似文献
77.
Noriyuki HORIUCHI Daishiro KUMAGAI Kotaro MATSUMOTO Hisashi INOKUMA Hidefumi FURUOKA Yoshiyasu KOBAYASHI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(10):1281-1283
Bovine dilated cardiomyopathy (DCM) is an autosomal recessive genetic disorder causing
congestive heart failure and subsequent death. Recently, a nonsense mutation c.343C>T
in the bovine optic atrophy 3 (OPA3) gene had been reported to cause the DCM in Holstein
cattle in Switzerland. However, the mutation has not been confirmed in bovine DCM outside
Switzerland. Nine Holstein Friesian cows that were macroscopically and histologically
diagnosed with or suspected of DCM and 12 control cows kept in Japan were tested for the
mutation. The mutation surrounding OPA3 DNA fragment was amplified by PCR and subjected to
direct sequences. The homogeneous c.343C>T mutation was proved to occur in all the
affected cows and not in the control cows. The present study is the first report of the
mutation in the DCM affected cows outside Switzerland. 相似文献
78.
79.
In our ongoing search for bioactive substances from marine organisms, novel alkaloids have been isolated. Pinnatoxins and pinnamine, potent shellfish poisons, were purified from the Okinawan bivalve Pinna muricata. Pinnatoxins activate Ca2+ channels. Halichlorine was isolated from the marine sponge Halichondria okadai. This compound inhibits the induction of VCAM-1. Drugs that block VCAM-1 may be useful for treating coronary artery diseases, angina, and noncardiovascular inflammatory diseases. Pinnaic acids, which are cPLA2 inhibitors, were also obtained from P. muricata. Interestingly, the structures of pinnaic acids are closely related to that of halichlorine. Norzoanthamine hydrochloride, isolated from the colonial zoanthid Zoanthus sp., suppresses decreases in bone weight and strength in ovariectomized mice, and could be a good candidate for an osteoporotic drug. Ircinamine, purified from the marine sponge Ircinia sp., has a reactive thioester. Aburatubolactams, inhibitors of superoxide anion generation, were isolated from Streptomyces sp. This article covers the bioactive marine alkaloids that have been recently isolated by this research group. 相似文献
80.
Hiroshi Tago Hirokazu Kimura Kunihisa Kozawa Koichi Fujie 《Water, air, and soil pollution》2005,163(1-4):269-280
We measured formaldehyde concentrations in ambient air at urban (Isesaki) and rural (Annaka) sites in Gunma Prefecture, Japan from June 1998 to March 2003. Measurements were carried out once in a month to obtain daily mean formaldehyde concentrations. At both the sites, mean concentrations of formaldehyde were significantly higher from April to September (summer) than from October to March (winter). Formaldehyde concentrations in Annaka were essentially as high as those in Isesaki in summer, but were significantly lower in winter. At both the sites, concentrations of formaldehyde and oxidants correlated significantly with one another in the summer; correlation coefficients in Annaka and Isesaki were 0.82 and 0.64, respectively. The fraction of formaldehyde formed photochemically based on concentrations of benzene was calculated to be as high as 80% in both the sites in summer. The results suggested that formaldehyde concentrations were high even in rural air, reflecting photochemical reactions rather than automobile exhaust. 相似文献