964 resultados para Coturnix coturnix japonica


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A female of Penaeus merguiensis de Man collected from Karachi fish harbour (8 May, 1993) was with a large specimen of bopyrid in its right gill chamber. Since this was the second record (see Tirmizi and Bashir, 1973) of a bopyrid from a species other than Parapenauopsis stylifera H. Milne-Edwards the specimen was examined out of curiosity.

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本发明涉及一种以海带为原料生产沼气的方法。包括以下步骤: (1)用水对海带进行漂洗;(2)对步骤(1)所得的海带进行晾干、粉碎处理,粉碎至粒径为100~200目;(3)将步骤(2)所得的海带投入到发酵装置中,加入接种物,接种物TS与海带TS的重量比为1∶ 1~5;(4)加淡水调整发酵装置内总固形物含量为2.5%~10%;(5) 控制步骤(4)中混合物的初始pH值在6.5~7.5;(6)将发酵装置密封,置于恒温水浴中,控制发酵温度在35±3℃。本发明以非常低廉的成本在获取沼气这一能源,为海带提供了一种新的利用途径,可大力推动海带栽培业的发展,而海带栽培业可以促进海洋生态环境的改善。

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Fringillidae is a large and diverse family of Passeriformes. So far, however, Fringillidae relationships deduced from morphological features and by a number of molecular approaches have remained unproven. Recently, much attention has been attracted to mitochondrial tRNA genes, whose sequence and secondary structural characteristics have shown to be useful for Acrodont Lizards and deep-branch phylogenetic studies. In order to identify useful phylogenetic markers and test Fringillidae relationships, we have sequenced three major clusters of mitochondrial tRNA genes from 15 Fringillidae, taxa. A coincident tree, with coturnix as outgroup, was obtained through Maximum-likelihood method using combined dataset of 11 mitochondrial tRNA gene sequences. The result was similar to that through Neighbor-joining but different from Maximum-parsimony methods. Phylogenetic trees constructed with stem-region sequences of 11 genes had many different topologies and lower confidence than with total sequences. On the other hand, some secondary structural characteristics may provide phylogenetic information on relatively short internal branches at under-genus level. In summary, our data indicate that mitochondrial tRNA genes can achieve high confidence on Fringillidae phylogeny at subfamily level, and stem-region sequences may be suitable only at above-family level. Secondary structural characteristics may also be useful to resolve phylogenetic relationship between different genera of Fringillidae with good performance.

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Background: The Galliformes is a well-known and widely distributed Order in Aves. The phylogenetic relationships of galliform birds, especially the turkeys, grouse, chickens, quails, and pheasants, have been studied intensively, likely because of their close association with humans. Despite extensive studies, convergent morphological evolution and rapid radiation have resulted in conflicting hypotheses of phylogenetic relationships. Many internal nodes have remained ambiguous. Results: We analyzed the complete mitochondrial (mt) genomes from 34 galliform species, including 14 new mt genomes and 20 published mt genomes, and obtained a single, robust tree. Most of the internal branches were relatively short and the terminal branches long suggesting an ancient, rapid radiation. The Megapodiidae formed the sister group to all other galliforms, followed in sequence by the Cracidae, Odontophoridae and Numididae. The remaining clade included the Phasianidae, Tetraonidae and Meleagrididae. The genus Arborophila was the sister group of the remaining taxa followed by Polyplectron. This was followed by two major clades: ((((Gallus, Bambusicola) Francolinus) (Coturnix, Alectoris)) Pavo) and (((((((Chrysolophus, Phasianus) Lophura) Syrmaticus) Perdix) Pucrasia) (Meleagris, Bonasa)) ((Lophophorus, Tetraophasis) Tragopan))). Conclusions: The traditional hypothesis of monophyletic lineages of pheasants, partridges, peafowls and tragopans was not supported in this study. Mitogenomic analyses recovered robust phylogenetic relationships and suggested that the Galliformes formed a model group for the study of morphological and behavioral evolution.

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Temperature effect on the pathogenicity of selected Edwardsiella tarda V-1 strain to Japanese eel, Anguilla japonica was investigated. To evaluate the effects of both pathogen incubation temperature and fish cultivation temperature on pathogen pathogenicity a two-factor design was conducted. E. tarda was incubated at 15, 20, 25, 30 and 37±1°C, and the fish (mean weight: 100g) were reared at 15, 20, 25 and 28±1°C respectively. The fish reared at different temperatures were infected with the E. tarda incubated at different temperatures. The results of a 4-day LD50 test showed that temperature significantly affected the pathogenicity of E. tarda (p<0.01) and the interaction between the two factors was also significant (p<0.01). For fish reared at 20°C the pathogenicity of E. tarda was the highest at 30°C of pathogen incubation. When the fish rearing temperature was raised to 25 and 28°C, the pathogenicity of E. tarda incubated at all temperatures increased. Isolation testing demonstrated results similar to those of LD50. The selected isolate was virulent to eel, but pathogenicity varied with temperature.

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The fanning of Chinese mitten crab, a quality aquatic product in China and neighbouring Asian countries, has been developing rapidly in China since last decade. It reached a total yield of 3.4 X 10(5) tonnes in 2002. Due to the successive over-stocking year after year, many lakes in the mid-lower Yangtze Basin, the main farming area, are under deterioration, leading to a reduction of crab yield and quality, and, subsequently, a loss of fanning profits. Aiming at a normal development of crab culture and the sustainable use of lakes, an annual investigation dealing with lake environmental factors in relation to stocked crab populations was carried out at 20 farms in 4 lakes. The results show that the submersed macrophyte biomass (B-Mac) is the key factor affecting annual crab yield (CY). Using the ratio of Secchi depth to mean depth (Z(SD)/Z(M)), an easily measured parameter closely correlated to BMac, as driving variable, 10 regression models of maximal crab yields were generated (r(2) ranging 0.49-0.81). Based on the theory of MSY (Maximum Sustainable Yield), in combination with body-weight (BW) and recapture rate (RR) of adult crabs, a general optimal stocking model was eventually formulated. All models are simple and easy to operate. Comments on their applications and prospects are given in brief. (c) 2006 Elsevier B.V. All rights reserved.

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在本研究中我们首次从雨蛙皮肤分泌液中分离得到了一种神经毒素(命名为Anntoxin)和一种干细胞自我更新支持因子(命名为AnSF)。随后,我们通过构建雨蛙皮肤cDNA 文库,利用特异引物筛选到Anntoxin 和AnSF 的cDNA 编码序列,前者的Gene Bank 登录号为FJ598043,后者还在等待分配登录号。Anntoxin 具有60 个氨基酸,是一种Kunitz 类型的丝氨酸蛋白酶抑制剂,构建Anntoxin 的3D-NMR 溶液结构,证实Anntoxin 不同于有三对二硫键(键组合模式:1-6,2-4,3-5)的Kunitz 类型丝氨酸蛋白酶抑制剂,它只有两对二硫键(组合模式:1-4,2-3)。AnSF 具有123 个氨基酸,在C 端具有和Calmadolin 同源的两个EF 手指结构,能够支持人类胚胎干细胞(hESC)和猴神经干细胞(rNSC)的自我更新。为了进行Anntoxin 的生物活性和结构分析,我们在体外成功表达了 Anntoxin,获得了大量的重组Anntoxin(rAnntoxin)。经过生物活性分析, rAnntoxin 和天然分离到的Anntoxin 生物活性相当,都具有很强的胰蛋白酶抑制剂活性。Anntoxin 是一种Kunitz 类型的丝氨酸蛋白酶抑制剂,和来源于芋螺(Cone Snail)的神经毒素Conkunitzin-S1,黑色眼镜蛇毒液(black cobra, Dendroaspis polylepis polylepis)的树突毒素δ-DaTX 或蛋白酶抑制剂K 分别具有32.8%和36.7%的相同序列,和鱼类(fish)来源的Stonustoxin 也有一定的同源性。利用膜片钳技术分别检测Anntoxin 对大鼠背根神经节(rat DRG)上Na+通道,K+通道,Ca2+通道的作用,结果证明Anntoxin 对河豚毒素敏感(TTX-S)的钠离子通道(Nav)有较强的抑制活性,对 K+通道,Ca2+通道作用不明显。随后我们在非洲爪蟾卵母细胞上表达几种典型和常用于测试对亚型K+通道作用的Kv1.1,Kv1.2,Kv1.3,Kv2.1 和 Kv4.2,Kv4.3,Anntoxin 对这些亚型K+通道上的K+电流都没有明显影响。我们成功构建了Anntoxin 的3D-NMR 溶液结构(NMR 号:PDB ID 2KCR, BMRB ID 16094),证实Anntoxin 具有典型的Kunitz 结构,由反向平行的 β–折叠片和α–螺旋及转角组成梨形结构。利用RT-PCR,WesternBlot 以及 ELISA 技术,发现在皮肤、脑、肝、胃和肠中都能检测Anntoxin mRNA 转录,但只在皮肤、脑、肝和胃中有蛋白表达,表达量分别为29.5、5.39、 4.80 和2.02 微克/克鲜重,可以看出Anntoxin 在皮肤中大量表达,是皮肤分泌液中非常重要的组成部分。因为皮肤是雨蛙接触外界的第一屏障,雨蛙的生存环境中存在很多潜在威胁,比如微生物、吸血昆虫、鸟类、爬行动物、哺乳动物等,所以Anntoxin 有可能是雨蛙适应环境的重要化学武器,于是我们测试了Anntoxin 对甜菜夜蛾幼虫(Laphygma exigua Hubner)、水蛇(Enhydris plumbea)、鹌鹑(Coturnix coturnix)、昆明小鼠(Kunming mice)的急性毒性,其LD50 分别为50,450,2500 和3000 微克/千克体重,说明在华西雨蛙皮肤中大量表达的Anntoxin 对几类潜在天敌确实有较强的杀灭作用。为了检测AnSF 的生物学活性,我们在体外成功表达了AnSF,获得了大量rAnSF。设计三个浓度梯度10、100 和500ng/ml,把AnSF 和hESC 共培养,发现在10~100 ng/ml 浓度时对hESC 的自我更新有支持作用;设计三个浓度梯度10、100 和500ng/ml,把AnSF 和rNSC 共培养,发现在 10ng/ml 时对rNSC 的自我更新有较强的支持作用。在超过500ng/ml 高浓度时,AnSF 对hESC 和rNSC 都有明显的细胞毒性作用,对rNSC 的毒性作用更明显。利用RT-PCR 技术,我们检测了雨蛙的皮肤、肌肉、肝脏、胰脏、胃、肠、心脏和脑,AnSF 只在皮肤中有少量表达。这表明AnSF 可能只参与雨蛙皮肤干细胞库的维持,保持皮肤内环境稳定,因为蛙类的皮肤细胞要负责产生大量活性物质参与先天免疫和抗氧化等重要的生理活动,需要经常更新,而AnSF 的存在可能保证雨蛙皮肤干细胞库容量稳定,不断分化出各种成熟的皮肤细胞来使皮肤能够得到足够和及时的更新,保证其功能的正常行使。所以AnSF 是维持华西雨蛙皮肤内环境稳定的重要物质。

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To establish a molecular-marker-assisted system of breeding and genetic study for Laminaria japonica Aresch., amplified fragment length polymorphism (AFLP) was used to construct a genetic linkage map of L. japonica featuring 230 progeny of F-2 cross population. Eighteen primer combinations produced 370 polymorphic loci and 215 polymorphic loci segregated in a 3:1 Mendelian segregation ratio (P <= 0.05). Of the 215 segregated loci, 142 were ordered into 27 linkage groups. The length of the linkage groups ranged from 6.7 to 90.3 centimorgans (cM) with an average length of 49.6 cM, and the total length was 1,085.8 cM, which covered 68.4% of the estimated 1,586.9 cM genome. The number of mapped markers on each linkage group ranged from 2 to 12, averaging 5.3 markers per group. The average density of the markers was 1 per 9.4 cM. Based on the marker density and the resolution of the map, the constructed linkage map can satisfy the need for quantitative trait locus (QTL) location and molecular-marker-assisted breeding for Laminaria.

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Accumulations of selenium in kelp Laminaria japonica cultured in seawater was achieved by adding selenite (Na2SeO3) with or without N-P (NaNO3 + NaH2PO4) nutrients at different concentrations. Biotransformation of selenium in the kelp was investigated through measuring the selenium of biological samples and different biochemical fractionations. The results showed that the optimal selenite-enrichment concentration is 200 mg L-1, which can allow the kelp to accumulate a total selenium content from 0.51 +/- 0.15 to 26.23 +/- 3.12 mug g(-1) of fresh weight (fw). Selenium composition analysis of kelp (control group) showed that selenium is present as organic selenium, which is up to 86.22% of the total selenium, whereas inorganic selenium is barely 4.85%. When L. japonica was exposed for 56 h in seawater containing 200 mg L-1 Na2SeO3, the organic selenium was 16.70 mug g(-1) of fw (68.23%) and inorganic selenium was 4.71 mug g(-1) of fw (19.26%). The capability of accumulation of selenium was further enhanced by adding N-P nutrients to the selenite-enriched medium. Total selenium is increased to be 33.65 mug g(-1) of fw at optimal concentration of N-P nutrient (150 mg L-1 NaNO3 and 25 mg L-1 NaH2PO4), whereas the inorganic selenium was not increased and remained at 4.597 mug g(-1) of fw (13.36%), and the increased part of selenium was organic selenium. This implied that kelp L. japonica could effectively transform inorganic selenium into organic selenium through metabolism.

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A human acidic fibroblast growth factor gene, hafgf, was successfully transferred into Laminaria japonica (kelp) gametophytes via microprojectile bombardment using the biolistic PDS-1000/He gene gun. Following phosphinothricin screening, PCR detection and Southern blot analysis, transgenic L. japonica gametophytes were cultivated in an illuminated bubble-column bioreactor to optimize growth conditions. A maximal final dry cell density of 1,695 mg l(-1) was obtained in a batch culture having an initial dry cell density of 129.75 mg l(-1). This was achieved using an aeration rate of 1.08 l air min(-1) l(-1) culture in a medium containing 1.5 mM inorganic nitrate and 0.15 mM phosphate. In addition, the relationship between different nitrogen sources and growth of transgenic gametophytes indicated that both urea and sodium nitrate were effective nitrogen sources for cell growth, while ammonium ions inhibited growth of these gametophytes.

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In this study, a full-length cytosolic heat shock protein 70 complementary DNA (cDNA) of Laminaria japonica (designated as LJHsp70) was obtained by reverse transcriptase-polymerase chain reaction (RT-PCR) coupled with rapid amplification of cDNA ends. The full length of LJHsp70 cDNA was 2,918 bp, with a 5' untranslated region of 248 bp, a 3' untranslated region of 696 bp, and an open reading frame of 1,974 bp encoding a polypeptide of 657 amino acids with an estimated molecular mass of 72.03 kDa and an estimated isoelectric point of 4.97. There was highly repeated sequence of CAA in 5' untranslated region of LJHsp70. The result of phylogenetic tree of Hsp70s, the BLAST program, analysis and cytosolic Hsp70-specific motif of LJHsp70 verified that the cloned LJHsp70 belonged to cytosolic Hsp70 family. Three typical Hsp70 signature motifs were detected in LJHsp70 by InterPro analysis. Under different stress conditions, messenger RNA (mRNA) expression levels of LJHsp70 were quantified by quantitative RT-PCR. To L. japonica sporophytes kept in different temperatures for 1 h, the expression level of LJHsp70 at 30A degrees C was highest and twofold higher than that at 10A degrees C. To L. japonica sporophytes kept at 25A degrees C for different times, the mRNA expression level of LJHsp70 reached a maximum level after 7 h and then dropped progressively. The expression level of LJHsp70 at 0 or 5aEuro degrees salt concentration for 2 h was twofold higher than that at 30aEuro degrees salt concentration for 2 h. The results showed that LJHsp70 may be a kind of potential biomarker used to monitor environment conditions.

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In this study, the background activity of beta-glucuronidase (GUS) was analyzed histochemically and fluorometrically in the negative control of Laminaria japonica (Phaeophyta) thalli, showing low level of activity. GUS gene transformation without selectable gene in L. japonica was performed using four different promoters, i.e., Cauliflower mosaic virus 35S promoter (CaMV35S) from cauliflower mosaic virus, ubiquitin promoter (UBI) from maize, adenine-methyl transfer enzyme gene promoter (AMT) from virus in green alga Chlorella, and fucoxanthin chlorophyll a/c-binding protein gene promoter (FCP) from diatom Phaeodactylum tricornutum. The GUS transient activity was determined fluorometrically after bombarding sliced parthenogenetic sporophytes explants, and it was found that the activity resulting from CaMV35S and FCP promoters (in 114.3 and 80.6 pmol MU min(-1) (mg protein)(-1), respectively) was higher than for the other two promoters. The female gametophytes were bombarded and regenerated parthenogenetic sporophytes. FCP was the only promoter that resulted in detectable GUS chimeric expression activity during histochemical staining and polymerase chain reaction. Results of Southern blot showed that GUS gene was integrated with the L. japonica genome.

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RNA isolation is difficult in some plants and algae because phenolics, polysaccharides, or other compounds can bind or co-precipitate with RNA, and because the success of RNA isolation can be strain-specific and species-specific. To create an improved RNA isolation protocol for Laminaria japonica Aresch (Laminariaceae, Phaeophyta), four methods for extracting RNA were tested. A cetyltrimethylammonium bromide (CTAB)-based RNA extraction protocol was developed that clearly showed 28S and 18S ribosomal RNA bands and produced RNA with high yield (68 mu g g(-1) fresh weight) and high quality (A (260/280) ratio 1.96 +/- 0.05). The isolated RNA was intact, and RT-PCR analysis confirmed that further molecular application is feasible.