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51.
52.
Kimata S Sakurai T Nozue Y Kasahara T Yamaguchi N Karino T Shibayama M Kornfield JA 《Science (New York, N.Y.)》2007,316(5827):1014-1017
In the rich and long-standing literature on the flow-induced formation of oriented precursors to polymer crystallization, it is often asserted that the longest, most extended chains are the dominant molecular species in the "shish" of the "shish-kebab" formation. We performed a critical examination of this widely held view, using deuterium labeling to distinguish different chain lengths within an overall distribution. Small-angle neutron-scattering patterns of the differently labeled materials showed that long chains are not overrepresented in the shish relative to their concentration in the material as a whole. We observed that the longest chains play a catalytic role, recruiting other chains adjacent to them into formation of the shish. 相似文献
53.
It is concluded that mitochondria are involved in three steps of porphyrin and heme biosynthesis-first, in the formation of delta-aminolevulinic acid from glycine and active succinate; second, in the synthesis of protoporphyrin; third, in the incorporation of iron into the porphyrin ring-that is, in heme formation. 相似文献
54.
Noboru SASAKI Yoshinori IKENAKA Yumiko INOUE Takahiro ICHISE Noriyuki NAGATA Mayumi ISHIZUKA Syouta MM NAKAYAMA Kensuke NAKAMURA Mitsuyoshi TAKIGUCHI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(4):648
Measurement of urinary metanephrines in spot samples is used for the diagnosis of canine pheochromocytoma (PC). We describe a simple analytical method based on liquid chromatography tandem mass spectrometry (LC-MS/MS) for measuring free metanephrine (MN) and normetanephrine (NMN) in spot urine samples. Using the developed method, we evaluated the stability of urinary free-MN and free-NMN at various storing conditions. In addition, we assessed the feasibility of urinary free-MN and -NMN measurement for diagnosing PC. Urine samples were mixed with stable isotope internal standards and thereafter purified by ultrafiltration. The purified samples were analyzed by LC-MS/MS in the multiple reaction monitoring mode after separation on a multimode octa decyl silyl column. The coefficient of variation of free-MN and -NMN measurement was 7.6% and 5.5%, respectively. The linearity range was 0.5–10 µg/l for both analytes. Degradation was less than 10% for both analytes under any of the storage conditions. The median free-NMN ratio to creatinine of 9 PC dogs (595, range 144–47,961) was significantly higher (P<0.05) than that of 13 dogs with hypercortisolism (125, range 52–224) or 15 healthy dogs (85, range 50–117). The developed method is simple and may not require acidification of spot urine. The results of this preliminary retrospective study suggest that the measurement of urinary free metanephrines is a promising tool for diagnosing canine PC. 相似文献
55.
Ayane Konta Shinichiro Ogawa Makoto Kimata Kazuo Ishii Yoshinobu Uemoto Masahiro Satoh 《Animal Science Journal》2020,91(1)
The performance of the two‐trait animal model that regards the first parity and later parities as two different traits in estimating genetic parameters for number of born alive (NBA) was examined using real and simulated data. Genetic parameters for NBA were estimated in purebred Landrace and Large White pigs using a single‐trait repeatability model (Model 1) that regards all parities as the same trait and a two‐trait animal model (Model 2) that regards the first and the later parities as different traits. For Model 2, the permanent environmental effect was fitted to only the records of the later parities. Heritability for NBA estimated using Model 1 was 0.12 for Landrace and 0.11 for Large White. Estimated heritability for NBA of the first parity and the later parities was 0.21 and 0.16, respectively, for Landrace; 0.18 and 0.16, respectively, for Large White obtained using Model 2, and higher than those in both breeds obtained using Model 1. Further results based on data simulated using the Monte Carlo method suggest that estimated additive genetic variance could be more biased using Model 2 than Model 1. 相似文献
56.
Abstract. Mass mortalities of hatchery-reared Japanese parrotfish larvae and juveniles, Oplegnathus fasciatus (Temminck & Schlegel), have occurred in Nagasaki Prefecture. Light and electron microscopic examinations showed that the only consistent histopathological feature was extensive nervous necrosis in the spinal cord, spinal ganglia and brain. Numerous non-enveloped virus particles, icosahedral in morphology and measuring about 34 nm in diameter, were found in the cytoplasm of affected neurones and glial cells. Such nervous necrosis is believed to be the major cause of the mass mortalities of hatchery-reared Japanese parrotfish larvae and juveniles. 相似文献
57.
Yoshinobu HIRAOKA Eri OHSAKA Kimiyoshi NARITA Kimiko YAMABE Nobuo SEKI 《Fisheries Science》2004,70(6):1130-1136
ABSTRACT: The aim of this study was to develop a practical preventive method for color deterioration of sliced or filleted yellowtail muscle, especially of dark muscle, during frozen storage and post thawing. When the sliced meats were packaged in a vacuum with low oxygen permeable flexible films and then stored frozen below −40°C, no significant discoloration or browning of dark muscle was observed for 9 months or more. For higher temperature storage at −20°C or −30°C, nitrogen gas substituted packaging was a useful practical method for storing sliced meats for 6 weeks. In order to prevent color deterioration of sliced meats after thawing and subsequent storage at 0°C, the efficacy of materials of packaging was investigated. The most desirable result was obtained by using a film with oxygen permeability of 50–90 cm3 /m2 per 24 h. 相似文献
58.
59.
Masakatsu NOHARA Keiichi HISAEDA Tetsushi ONO Yoichi INOUE Kouji OGAWA Akihisa HATA Kenichi SIBANO Hajime NAGAHATA Noboru FUJITANI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(7):964
There has been an increase in temperature and the incidence of extreme weather events, such as heat wave, due to global warming, which has promoted the incidence of livestock diseases. Therefore, it is important to examine the effect of changes in environmental parameters on livestock performance. The aim of this study was to examine the relationship between ambient environmental conditions in livestock pen and the physiological parameters of Holstein dairy cows. The results showed that there was a decrease in the red blood cell counts, hemoglobin concentrations, and mean corpuscular hemoglobin concentration of the cows with increasing pen temperature, wet bulb globe temperature (WBGT), and temperature humidity index (THI). Additionally, high daily variation in temperature caused a decrease in the serum albumin levels of the cows. Moreover, the lowest serum calcium, inorganic phosphorus, and magnesium concentrations were observed in November, and were negatively correlated with the 24-hr temperature, WBGT, and THI range of the pen prior to sampling. Multiple regression analysis showed a positive correlation between serum cortisol concentration and 24-hr WBGT range of the pen prior to samplings and packed cell volume. However, serum cortisol and total protein concentrations were negatively correlated. Overall, the findings of the study suggest that large variation in temperature induced stress in the cows, which could be overcome by increased water consumption and improved protein digestion and absorption by the animals, and the addition of minerals, such as calcium to the diet. 相似文献
60.
Mai YAMAMOTO Takashige KASHIMOTO Ping TONG Jianbo XIAO Michiko SUGIYAMA Miyuki INOUE Rie MATSUNAGA Kohei HOSOHARA Kazue NAKATA Kenji YOKOTA Keiji OGUMA Koichiro YAMAMOTO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(7):823-828
Vibrio vulnificus is the causative agent of primary septicemia, wound
infection and gastroenteritis in immunocompromised people. In this study, signature-tagged
mutagenesis (STM) was applied to identify the virulence genes of V.
vulnificus. Using STM, 6,480 mutants in total were constructed and divided into
81 sets (INPUT pools); each mutant in a set was assigned a different tag. Each INPUT pool
was intraperitoneally injected into iron-overloaded mice, and in vivo
surviving mutants were collected from blood samples from the heart (OUTPUT pools). From
the genomic DNA of mixed INPUT or OUTPUT pools, digoxigenin-labeled DNA probes against the
tagged region were prepared and used for dot hybridization. Thirty tentatively attenuated
mutants, which were hybridized clearly with INPUT probes but barely with OUTPUT probes,
were negatively selected. Lethal doses of 11 of the 30 mutants were reduced to more than
1/100; of these, the lethal doses of 2 were reduced to as low as 1/100,000.
Transposon-inserted genes in the 11 attenuated mutants were those for IMP dehydrogenase,
UDP-N-acetylglucosamine-2-epimerase, aspartokinase, phosphoribosylformylglycinamidine
cyclo-ligase, malate Na (+) symporter and hypothetical protein. When mice were immunized
with an attenuated mutant strain into which IMP dehydrogenase had been inserted with a
transposon, they were protected against V. vulnificus infection. In this
study, we demonstrated that the STM method can be used to search for the virulence genes
of V. vulnificus. 相似文献