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991.
Bai GR Sakoda Y Mweene AS Fujii N Minakawa H Kida H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(1):35-40
To improve the sensitivity of a kit, ESPLINE INFLUENZA A&B for rapid diagnosis of influenza by detecting influenza A or B virus specific nucleoproteins (NP), the ESPLINE INFLUENZA A&B-N was developed by using newly established monoclonal antibodies (MAbs) to the respective NP molecule. MAbs FVA2-11 and FrB1-03 recognize the epitope on the amino acid region 59-130aa of the NP molecule of influenza A virus, and that on the region 72-191aa of the NP of influenza B virus, respectively. The new kit detected influenza A and B virus antigens with a detection limit of 10(2.0)-10 (2.7) pfu/test, which is 4-1000 times higher than that of the original kit. Importantly, this kit detected each of influenza A viruses of the known hemagglutinin (HA) subtypes (H1-H15) including the H5N1 viruses recently isolated from human and avian sources in Asia. The kit also detected all of the 15 representative influenza B virus strains tested. The ESPLINE INFLUENZA A&B-N is thus a rapid and highly sensitive and specific kit for the diagnosis of either influenza A or B virus infections. 相似文献
992.
Katsumata E Jaroenporn S Katsumata H Konno S Maeda Y Watanabe G Taya K 《The Journal of reproduction and development》2006,52(1):65-71
Killer whales were used to evaluate peripartum changes and interactions between body temperature and circulating progesterone concentration. Daily body temperature was measured between 0800 h and 0830 h before activity. Body temperature clearly increased during the first phase of pregnancy, and this was followed by a gradual decline until full term. The initial increase was paralleled by circulating levels of progesterone. A decrease in body temperature was first detected on day 5 (p < 0.01) before parturition, and body temperature decreased significantly every 2 days until delivery. Five days before delivery, body temperature was 0.3 C lower than the mean value during the pregnancy period, and the decrease was more marked on day 1 before delivery (0.8 C). Serum progesterone levels during pregnancy showed a general pattern of initial rapid elevation (increasing phase), followed by a gradual decline (decreasing phase) throughout the remainder of pregnancy. However, statistically significant correlations between body temperature and progesterone pattern were only found only during the increasing phase. These results suggest that monitoring body temperature variation can be considered valuable for predicting impending parturition in killer whales. 相似文献
993.
Han YJ Miah AG Yoshida M Sasada H Hamano K Kohsaka T Tsujii H 《The Journal of reproduction and development》2006,52(5):657-662
Porcine relaxin is a peptide hormone belonging to the insulin super family that has a variety of biological functions. The present experiment was designed to investigate the effects of relaxin on sperm function and on in vitro fertilization (IVF) of porcine oocytes. Porcine spermatozoa were washed, swum-up, and incubated for 1-4 h in mTALP medium supplemented with 0, 20 or 50 ng/ml porcine relaxin. Motility was determined by observing the type of forward movement of the spermatozoa, and acrosome status was evaluated by applying the triple staining technique. Immature oocytes were aspirated from antral follicles and matured in IVM medium (modified NCSU-37). Matured oocytes were co-cultured with spermatozoa in IVF medium (mTALP) supplemented with 0, 5, 10, 15 or 20 ng/ml relaxin. After 6 h of sperm-oocyte co-incubation, putative zygotes were cultured for 18 h in oocyte culture medium NCSU-37 and then assessed for the rates of monospermy, polyspermy, and male pronucleus formation after acetic orcein staining. Relaxin improved (P<0.05) sperm motility and increased the percentage of acrosome-reacted live spermatozoa during 1-4 h of incubation, although viability was not significantly improved. Significantly (P<0.05) the highest percentage of monospermic (31.7%) and lowest percentage of polyspermic (16.5%) fertilization was achieved from the sperm-oocyte co-culture group treated with 20 ng/ml relaxin as compared to other groups. The percentage of male pronucleus formation was significantly (P<0.05) greater in the 20 ng/ml relaxin-treated sperm-oocyte co-culture group than in the other groups. These results indicate that supplementation with relaxin is capable of improving sperm function and fertilization of porcine oocytes in vitro. 相似文献
994.
Ikeda H Stark J Fischer H Wagner M Drdla R Jäger T Sandkühler J 《Science (New York, N.Y.)》2006,312(5780):1659-1662
Inflammation and trauma lead to enhanced pain sensitivity (hyperalgesia), which is in part due to altered sensory processing in the spinal cord. The synaptic hypothesis of hyperalgesia, which postulates that hyperalgesia is induced by the activity-dependent long-term potentiation (LTP) in the spinal cord, has been challenged, because in previous studies of pain pathways, LTP was experimentally induced by nerve stimulation at high frequencies ( approximately 100 hertz). This does not, however, resemble the real low-frequency afferent barrage that occurs during inflammation. We identified a synaptic amplifier at the origin of an ascending pain pathway that is switched-on by low-level activity in nociceptive nerve fibers. This model integrates known signal transduction pathways of hyperalgesia without contradiction. 相似文献
995.
Shimoda H Tanaka J Yamada E Morikawa T Kasajima N Yoshikawa M 《Journal of agricultural and food chemistry》2006,54(8):2915-2920
Pollenosis is a disease that affects 1 in 10 of the Japanese population. During the season of cedar pollen dispersal, many patients suffer from symptoms such as sniffling, sternutation, and itching of the eyes. Japanese butterbur is a popular vegetable and is one of the few domestic vegetables in Japan. The anti type I allergic effects of an aqueous ethanol extract from aerial parts of Japanese butterbur (JBE) were evaluated in rats and RBL-2H3 mast cells. In the passive cutaneous anaphylaxis reaction in rats, a single oral treatment of JBE (1000 mg/kg) was found to suppress the reaction. In IgE-sensitized RBL-2H3 cells, JBE (10-100 microg/mL) inhibited beta-hexosaminidase release, leukotriene C(4)/D(4)/E(4) synthesis, and TNF-alpha production. Moreover, a high concentration of JBE (1000 microg/mL) suppressed smooth muscle constriction induced by histamine (10 microM) and leukotriene D(4) (10 nM) in a guinea pig trachea strip. The search for components in JBE with an inhibitory activity on mast cell degranulation was guided by inhibition of beta-hexsosaminidase release. Two eremophilane-type sesquiterpenes, six polyphenolic compounds, and two triterpene glycosides were isolated. Of these compounds, fukinolic acid, a principal polyphenol constituent, showed potent inhibitory activity (IC(50) value = 2.1 microg/mL). Consequently, On the basis of its inhibition of mast cell activation and direct smooth muscle reaction induced by released mediators, JBE was found to suppress the type I allergic reaction. 相似文献
996.
We explored the use of ecological niche-modeling from data compiled in a participatory program of thousands of volunteer observers to quantitatively evaluate the spatial risk of invasion by the alien species Bombus terrestris. B. terrestris has been commercially introduced to Japan for the pollination of greenhouse tomato crops since 1991. Recently, naturalized populations of this species have spread rapidly, particularly in Hokkaido, northern Japan. Two niche-based models were constructed from independent data sets (presence-absence and presence-only data sets) and were used to validate one another. Both models performed well and indicated that the data compiled by participatory programs were useful for generating predictive models of the potential distribution of this invasive species. The models also revealed that the potential distribution of B. terrestris is negatively related to the proportion of woodland area, which corresponds to the known biology of this species. In contrast, the effect of the number of colonies introduced for tomato pollination (represented by tomato production) did not significantly affect the distribution of B. terrestris, indicating that its spread is now entering a phase of dispersal from established feral populations and that primary dispersal from commercial colonies in greenhouses is no longer a limiting factor for the distribution of this invasive species. 相似文献
997.
Shuri Kato Asako Matsumoto Kensuke Yoshimura Toshio Katsuki Kojiro Iwamoto Yoshiaki Tsuda Shogo Ishio Kentaro Nakamura Kazuo Moriwaki Toshihiko Shiroishi Takashi Gojobori Hiroshi Yoshimaru 《Breeding Science》2012,62(3):248-255
Numerous cultivars of Japanese flowering cherry (Prunus subgenus Cerasus) are recognized, but in many cases they are difficult to distinguish morphologically. Therefore, we evaluated the clonal status of 215 designated cultivars using 17 SSR markers. More than half the cultivars were morphologically distinct and had unique genotypes. However, 22 cultivars were found to consist of multiple clones, which probably originate from the chance seedlings, suggesting that their unique characteristics have not been maintained through propagation by grafting alone. We also identified 23 groups consisting of two or more cultivars with identical genotypes. Most members of these groups were putatively synonymously related and morphologically identical. However, some of them were probably derived from bud sport mutants and had distinct morphologies. SSR marker analysis provided useful insights into the clonal status of the examined Japanese flowering cherry cultivars and proved to be a useful tool for cultivar characterization. 相似文献
998.
Kentaro Ikeda Shinpei Banno Ken Watanabe Masashi Fujinaga Hideki Ogiso Hiroshi Sakai Hitoshi Tanaka Shizue Miki Satoshi Shibata Toshimasa Shiraishi Makoto Fujimura 《Journal of General Plant Pathology》2012,78(5):331-337
Chinese cabbage yellows caused by Verticillium dahliae and V. longisporum is one of the most economically important diseases in Japan. Verticillium isolates from infected Chinese cabbage in Japan were identified as V. dahliae and V. longisporum based on morphological characteristics and newly developed molecular genotyping methods using group I intron of 18S rDNA, mitochondrial-SSU rDNA and cob gene. Although the two species were equally virulent to Chinese cabbage in the greenhouse, V. longisporum was more virulent in the field compared with V. dahliae. Among the 67 Verticillium isolates from Chinese cabbage, 53 were V. longisporum and considered to be the major pathogen. The isolation frequency of V. longisporum was 98?% in Ibaraki and eastern Gunma where Chinese cabbage was cropped from autumn to winter. In contrast, the frequency was 48?% in Nagano and north to west Gunma where the plant was cropped in cool summer and highland conditions and the rests were V. dahliae. This is the first report to show the different geographical distribution of V. longisporum and V. dahliae in Chinese cabbage production area of Japan. 相似文献
999.
Kato A Obara K Igarashi T Tsuruoka H Nakagawa S Hirata N 《Science (New York, N.Y.)》2012,335(6069):705-708
Many large earthquakes are preceded by one or more foreshocks, but it is unclear how these foreshocks relate to the nucleation process of the mainshock. On the basis of an earthquake catalog created using a waveform correlation technique, we identified two distinct sequences of foreshocks migrating at rates of 2 to 10 kilometers per day along the trench axis toward the epicenter of the 2011 moment magnitude (M(w)) 9.0 Tohoku-Oki earthquake in Japan. The time history of quasi-static slip along the plate interface, based on small repeating earthquakes that were part of the migrating seismicity, suggests that two sequences involved slow-slip transients propagating toward the initial rupture point. The second sequence, which involved large slip rates, may have caused substantial stress loading, prompting the unstable dynamic rupture of the mainshock. 相似文献
1000.
Yukie Tada Norio Yano Hiroshi Takahashi Katsuhiro Yuzawa Hiroshi Ando Yoshikazu Kubo Akemichi Nagasawa Akio Ogata Dai Nakae 《Journal of toxicologic pathology》2012,25(4):233-239
Iron nanomaterials are of considerable interest for application to
nanotechnology-related fields including environmental catalysis, biomedical imaging, drug
delivery and hyperthermia, because of their superparamagnetic characteristics and high
catalytic abilities. However, information about potential risks of iron nanomaterials is
limited. The present study assessed pulmonary responses to a single intratracheal spray
instillation of triiron tetraoxide nanoparticles (magnetite) in rats. Ten-week-old male
and female Fischer 344 rats (n=5/group) were exposed to a single intratracheal spray
instillation of 0 (vehicle), 5.0, 15.0 or 45.0 mg/kg body weight (BW) of magnetite. After
14 days, the rats were sacrificed, and biological consequences were investigated. The lung
weights of the 15.0 and 45.0 mg/kg BW male and female groups were significantly higher
than those of the control groups. The lungs of treated rats showed enlargement and black
patches originating from the color of magnetite. The typical histopathological changes in
the lungs of the treated rats included infiltration of macrophages phagocytosing
magnetite, inflammatory cell infiltration, granuloma formation and an increase of goblet
cells in the bronchial epithelium. The results clearly show that instilled magnetite
causes foreign body inflammatory and granulating lesions in the lung. These pulmonary
responses occur in a dose-dependent manner in association with the increase in lung
weight. 相似文献