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YASUNORI KOYA KIYOSHI SOYANO KAZUHISA YAMAMOTO HIROYUKI OBANA TAKAHIRO MATSUBARA 《Fisheries Science》2003,69(1):137-145
ABSTRACT: The present study investigates the relationship between oocyte development and serum steroid hormone levels in captive Pacific herring, Clupea pallasii , during the first reproductive cycle. The process of oocyte development in Pacific herring belongs to the group-synchronous type. Maturity of the ovary was divided into six periods based on histological observation (i.e. immature (April to September), onset of vitellogenesis (August to October), progress of vitellogenesis (October to December), completion of vitellogenesis (December to March), maturation and spawning (March to April) and spent (late April)). The pattern of seasonal change in the gonadosomatic index (GSI) well reflected the ovarian maturity. Serum vitellogenin levels showed good correlation with change in GSI, which increased from September to a peak (4.2 ± 0.3 mg/mL) in March. Serum estradiol-17β (E2) levels elevated from September and reached a peak (15.8 ± 4.2 ng/mL) in December, and remained comparatively high until March, suggesting that the active vitellogenin synthesis during vitellogenesis is controlled by the high E2 level. 17,20β-Dihydroxy-4-pregnen-3-one showed a single sharp peak (2.4 ± 0.28 ng/mL) in early April of the second year, suggesting it was a maturation-inducing steroid in this species. 相似文献
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During spermatogenesis, many proteins are synthesized in the testis prior to the completion of sperm maturation. Many components are involved in the testicular protein synthesis and one of the components that is implicated in the polypeptide chain elongation is elongation factor 1α. In the present study, the molecular cloning of elongation factor 1α (EF-1α) was conducted from a testis cDNA library of the Nile tilapia. The cDNA for tilapia EF-1α (tEF-1α) contains a complete open reading frame encoding 462 amino acids. The predicted amino acid sequence of EF-1α shows an approximate 90% similarity to those identified in other teleost fish, such as medaka, sea bream and zebrafish. Northern blotting revealed that the gene is expressed in all of the examined tissues and in ovulated eggs. The results of in situ hybridization indicate that the gene is expressed specifically in Leydig cells in testis, suggesting the involvement of EF-1α as an actin-binding protein in the cluster formation of Leydig cells. In the ovary, the gene is expressed in the perinucleolus stage of oocytes, suggesting that EF-1α is also implicated in oocyte growth. 相似文献
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天然存在的精油中,松节油以其价格低廉平稳、供应充足而明显地被认为是作为精细化学品如:香料、食品添加剂、药物、农用化学品中间体的最重要的有机资源之一。当今迫切需要将基础研究用来对有机资源作重新评价和高水平的应用。本文介绍一系列有价值作为香料物质和食品添加剂的单萜化合物和倍半萜化合物,而这些香料与添加剂近来已发现与天然精油有关,并能由松节油合成。 相似文献
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Takamitsu TSUKAHARA Yoko YOSHIDA Toshiki TSUSHIMA Takumi WATANABE Noritaka MATSUBARA Ryo INOUE Kazunari USHIDA 《Animal Science Journal》2011,82(2):302-306
Early weaning induces villous atrophy in the small intestine (SI) of piglets. Oral administration of live lactic acid bacteria (LAB) can improve villous shortening. In this study, we evaluated the oral administration of a heat‐killed and dried cell preparation of Enterococcus faecalis (a LAB) strain EC‐12 against villous atrophy in early‐weaned mice (Experiment 1) and pigs (Experiments 2 and 3). Twelve 16‐days‐old mice were divided into two groups in Experiment 1: gavage of EC‐12 (10 mg/kg body weight (BW)/day), or control. On day 21, SI was collected. Eighteen 21‐day‐old pigs were divided into two groups in Experiment 2: gavage of EC‐12 (10 mg/kg BW/day), or control. After 10 days, the villous height of jejunum was measured. Six 21‐day‐old pigs were divided into two groups in Experiment 3: the basal diet supplemented with EC‐12 at 0.05%‐fed group, or the basal diet‐fed group. After 10 days, the villous height of jejunum was measured. The villous heights in SI were significantly higher by EC‐12 administration in all experiments. EC‐12 successfully improved the villous atrophy in the early‐weaned mice and pigs when EC‐12 was administered orally. 相似文献
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Daichi IJIRI Tomoko MATSUBARA Yukio KANAI Miho HIRABAYASHI 《Animal Science Journal》2012,83(4):331-337
Nuclear receptor subfamily 4, group A (NR4A) subgroup orphan receptors are rapidly induced by various physiological stimuli and have been suggested to regulate oxidative metabolism and muscle mass in mammalian skeletal muscle. The results showed that the NR4A subgroup orphan receptor, NOR‐1 (NR4A3), was acutely increased in skeletal muscles of neonatal chicks in response to short‐term cold exposure. The increased NOR‐1 gene expression was concomitant with cold‐induced changes in gene expression of both myostatin and proliferator‐activated receptor‐gamma coactivator‐1 (PGC‐1α), and the increase in skeletal muscle mass. These observations suggest that NOR‐1 might play a role in controlling skeletal muscle growth in cold‐exposed neonatal chicks. 相似文献
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YASUNORI KOYA KIYOSHI SOYANO KAZUHISA YAMAMOTO HIROYUKI OBANA TAKAHIRO MATSUBARA 《Fisheries Science》2002,68(5):1099-1105
The present study investigates the relationship between testicular development and serum steroid hormone levels in captive Pacific herring Clupea pallasii during the first reproductive cycle. The maturity of the testis was divided into five periods based on histological observation. These are early spermatogenic stage (April to July), mid-spermatogenic stage (August to November), late spermatogenic stage (December to March), functional maturation stage (early April) and spent stage (late April). The pattern of seasonal change in gonadosomatic index (GSI) clearly reflected testicular maturity. 11-Ketotestosterone (11-KT) levels increased from October to a peak level (6.58 ± 1.87 ng/mL) in January, and were maintained at this level until March. In contrast, testosterone levels were consistently low, less than 1 ng/mL, at all times. These results suggest that 11-KT is the predominant androgen that controls spermatogenesis in this species. 17,20β-Dihydroxy-4-pregnen-3-one (DHP) showed a single sharp peak (3.38 ± 0.35 ng/mL) in early April of the second year, suggesting that milt production is induced by DHP as in some other teleost species. 相似文献
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Takashi HARUMI Akiko SANO Hiroshi KAGAMI Takahiro TAGAMI Yuko MATSUBARA Mitsuru NAITO 《Animal Science Journal》2004,75(6):503-507
The D‐loop region in mitochondrial DNA (mtDNA) was sequenced and compared among six chickens. Eleven single nucleotide polymorphisms (SNP) were observed. For six of the SNP sites, polymerase chain reaction (PCR) primers that had each base (A, C, G and T) as the penultimate base at the 3′ end (N2 base) and bases specific to both alleles at the 3′ end were produced to type the polymorphisms. Twenty‐one out of 96 primers succeeded in distinguishing the SNP by the presence or absence of PCR product. This method provides an easy way to discriminate SNP in chicken mtDNA. 相似文献