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241.
Sinking rate of loricae of some common tintinnid ciliates 总被引:1,自引:0,他引:1
Sinking rate of empty loricae of seven tintinnid species was measured in settling chambers. The sinking rates normalized for 3% NaCl solution at 20d?C are 0.25-2.08 m day-1 for five hyaline loricae and 1.90 and 15.9 m day-1 for two agglutinated loricae. Positive relationships between sinking rate and size of hyaline loricae such as volume, surface area and nominal diameter were established, which favour the practical estimation of sinking rate of empty loricae discarded by natural tintinnid populations by measuring size composition. The slower sinking rate of hyaline loricae, compared with that of diatoms, indicates their availability as indicators of particular water masses in the ocean. Loricae incorporated into faecal pellets of zooplankton and marine snow also indicate the origin of these sinking particles. 相似文献
242.
Yamato SAJIKI Satoru KONNAI Reiko NAGATA Satoko KAWAJI Hayato NAKAMURA Sotaro FUJISAWA Tomohiro OKAGAWA Naoya MAEKAWA Yukinari KATO Yasuhiko SUZUKI Shiro MURATA Yasuyuki MORI Kazuhiko OHASHI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(2):162
Johne’s disease, caused by Mycobacterium avium subsp. paratuberculosis (MAP), is a chronic enteritis of ruminants. Previous studies have shown that programmed death-ligand 1 (PD-L1) is associated with the disease progression, and PD-L1 blockade activates MAP-specific Th1 responses in vitro. Here, we performed anti-PD-L1 antibody administration using 2 MAP-infected cattle at the late subclinical stage of infection. After administration, bacterial shedding was reduced or maintained at a low level. Additionally, MAP-specific Th1 cytokine production was upregulated, and CD69 expression was increased in T cells. Collectively, the treatment has a potential as a novel control method against Johne’s disease. 相似文献
243.
Takashi IKEDA Makoto ASANO Masatsugu SUZUKI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(5):846
There is a possibility that classical swine fever (CSF) virus outbreak has negative impacts on wild boar. To adequately manage native wild boar populations, wildlife managers need to gather the field data on wild boar and implement population management practices. We aimed to report the relative abundance index of wild boar before and after this outbreak. Our results showed that relative abundance index declined from 2017 (8.88 wild boars/100 trap days) to 2019 (2.03 wild boars/100 trap days), because of the negative impact of this virus and continuous culling programs. Although the eradication risk from the synergistic effect is low, wildlife managers need to consider the relationship between the trade-off between the risk of CSF and the conservation ecology risk of native species eradication. 相似文献
244.
245.
Demura H Kobayashi S Nemoto E Matsumoto N Furuya M Yukishita A Muranaka N Morita H Shirakawa K Maruya M Ohyama H Uo M Kubota T Hashimoto T Kawaguchi J Fujiwara A Saito J Sasaki S Miyamoto H Hirata N 《Science (New York, N.Y.)》2006,312(5778):1347-1349
The locations of the pole and rotation axis of asteroid 25143 Itokawa were derived from Asteroid Multiband Imaging Camera data on the Hayabusa spacecraft. The retrograde pole orientation had a right ascension of 90.53 degrees and a declination of -66.30 degrees (52000 equinox) or equivalently 128.5 degrees and -89.66 degrees in ecliptic coordinates with a 3.9 degrees margin of error. The surface area is 0.393 square kilometers, the volume is 0.018378 cubic kilometers with a 5% margin of error, and the three axis lengths are 535 meters by 294 meters by 209 meters. The global Itokawa revealed a boomerang-shaped appearance composed of two distinct parts with partly faceted regions and a constricted ring structure. 相似文献