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Embryonic and larval morphological development of Paralichthys dentatus
犬齿牙鲆胚胎及仔、稚、幼鱼形态发育观察

陈朴贤
海洋科学 , 2012,
Abstract: 犬齿牙鲆(Paralichthys dentatus)卵为端黄卵, 受精卵浮性, 卵径950~1 100 μm, 油球径200~225μm。在水温20.5~22.0℃, 盐度33 条件下培育, 受精后1 h 20 min 进入卵裂期, 6 h 10 min 进入囊胚期,11 h 20 min 进入原肠胚期, 19 h 10 min 发育到胚孔封闭期, 胚体形成, 26 h 50 min 尾芽出现, 33 h 35 min心跳开始, 48 h 10 min 开始孵化出仔鱼。初孵仔鱼平均全长2.59 mm±0.02 mm, 在培育水温为17.0~21.0℃, 盐度24~34 条件下, 胚后发育时序为: 1 日龄~9 日龄为仔鱼前期, 10 日龄平均全长5.52 mm±0.05 mm, 卵黄囊和油球完全吸收进入仔鱼后期; 40 日龄平均全长20.82 mm±0.67 mm, 各鳍鳍条发育形成进入稚鱼期; 65 日龄平均全长41.13 mm±0.88 mm, 全身鳞被完整进入幼鱼早期。
Backcrosses in interspecific hybridization in sunflower  [PDF]
Atlagi? Jovanka,Pankovi? Dejana,Pekanovi? Ana
Genetika , 2003, DOI: 10.2298/gensr0303187a
Abstract: When incorporating desirable traits (resistance to causal agents of various diseases) from the wild relatives into the cultivated sunflower, some undesirable ones are introduced too (branching, small head diameter, low oil content, etc). To overcome this problem, backcrosses (F1 interspecific hybrids x cultivated sunflower) are used, although very often desirable traits are lost in the process. Cytological analysis (meiosis and pollen viability) and molecular markers (RAPD) were used to estimate what portion of the parental species genome was present in (be interspecific hybrids of the F1 and BC1F1 generations. The results showed that the percentage of irregularities at meiosis increased from F1 to BC1F1 gen. They also indicated the presence of aneuploids and sterility in the cross between the hexaploid species H.rigidus and cultivated sunflower. The genetic distance between the parents was 83%, that between H.rigidus and the F1 hybrid 54 61%, and that between H.annuus and F1 hybrid 70-76%. In the BC1F1 generation, the genetic distance from Hannuus decreased to 58-66% and that from H.rigidus increased to 69-76%.
杂交鲆(牙鲆♀×夏鲆♂)胚胎发育的初步观察  [PDF]
于道德,肖志忠,徐世宏,马道远,李 军
海洋科学 , 2007,
Abstract: 通过人工调控促使亲本牙鲆(Paralichthysolivaceus)♀×夏鲆(Paralichthysdentatus)♂的性腺发育,人工干法授精获得杂交受精卵。杂交受精卵在温度为16.5~17.5℃,光照为100~400lx,微充气条件下孵化。对杂交鲆胚胎发育全过程进行连续观察并与牙鲆及夏鲆的胚胎发育进行比较。结果表明:杂交鲆卵裂方式与其他大部分硬骨鱼类一样,属于盘状卵裂。受精后经过2h30min进入2细胞期,7h45min进入囊胚期,15h10min进入原肠胚阶段,25h30min进入神经胚期,49h左右进入尾芽期。授精后63h左右发现初孵仔鱼,68h左右50%的仔鱼孵出。在杂交鲆的胚胎发育中,主要有2个发育特征与母本类似而与父本不同:视囊的出现要早于体节的分化;孵化前,仔鱼在卵膜内环绕卵黄囊不到1周。但是在其孵化时间上却与父本相似。
Biological activities of Rumex dentatus L: Evaluation of methanol and hexane extracts
N Fatima, M Zia, R Rehman, ZF Rizvi, S Ahmad, B Mirza, MF Chaudhary
African Journal of Biotechnology , 2009,
Abstract: Rumex dentatus L. (Plygonaceae) extracts were evaluated for antibacterial, antifungal, cytotoxic, antitumor and allopathic potential. The leaf, stem and root extracts were prepared in methanol and hexane by simple maceration. The methanol extracts of root and shoot were found effective against all the bacterial strains tested. Zone of inhibition ranged between 9.7 to 12.1 mm. While the hexane extracts inhibited fungal growth (up to 80%) more efficiently than the methanol extracts. Concentration of different the extracts of R. dentatus effectively inhibited tumor induction on the potato discs produced by wild type Agrobacterium strains At10 and At6. The root extracts either in methanol or hexane showed LD50 values below 1000 ppm in brine shrimp mortality assay. The methanol extracts of leaf and stem inhibited radish seed germination (70 and 61% respectively) and root length more than the hexane extracts. The R. dentatus methanol extract showed presence of alkaloids, saponins, anthraquinones and tannins while flavonoids were also found in both methanol as well as hexane extract.
牙鲆与夏鲆杂交及回交子代胚胎发育及早期生长比较  [PDF]
隋娟,徐世宏,王文琪,马道远,肖志忠,肖永双,刘清华,李军
海洋科学 , 2012,
Abstract: 通过人工授精技术对牙鲆(Paralichthysolivaceus)和夏鲆(Paralichthysdentatus)进行了正反交及回交实验,并比较了正反交、回交子代的胚胎发育时序和仔稚幼鱼的生长。结果表明:孵化水温18.0±0.5℃下,初孵仔鱼破膜用时为:牙鲆41h,正交鲆47h,回交牙鲆42h30min,回交夏鲆44h;16.5±0.5℃下,夏鲆61h40min,反交鲆66h。正交及两组回交子代在胚胎期均可正常发育。反交子代卵裂期出现异常,仅少数胚胎可以孵化。胚胎孵化后,在1~64日的培养过程中,反交鲆于3~4d内全部死亡,回交牙鲆发育至18日龄时全部死亡。正交鲆和回交夏鲆可正常发育,与牙鲆没有明显差别。
Lipophilic Constituents of Rumex vesicarius L. and Rumex dentatus L.  [PDF]
Mona A. Abou Elfotoh,Khaled A. Shams,Kevin P. Anthony,Abdelaaty A. Shahat,Magda T. Ibrahim,Nevein M. Abdelhady,Nahla S. Abdel Azim,Faiza M. Hammouda,Mostafa M. El-Missiry,Mahmoud A. Saleh
Antioxidants , 2013, DOI: 10.3390/antiox2030167
Abstract: Rumex dentatus L. and Rumex vesicarius L., of the family Polygonaceae, are edible herbs growing wild in Egypt. Their lipoid constituents were examined by both liquid chromatography/mass spectrometry (LC/MS) and by gas chromatography/mass spectrometry (GC/MS). Their essential oil compositions consisted mainly of thujene, limonene, fenchon, estragole, and anethole but at largely different concentration. Fatty acid compositions were similar among the two species and consisting of palmitic, oleic, linoleic and linolenic acids, with R. vesicarius containing much higher level of omega-3-fatty acids. Both of the crude lipid extracts of the two species showed strong antioxidant activity as a radical quenching agent against 2,2-diphenyl-1-picrylhydrazyl (DPPH) systems. Antioxidant activities were mostly associated with the polar lipid fractions. High performance thin layer chromatography (HPTLC), both in the normal and reversed phase,as well as liquid chromatography/mass spectrometry (LC/MS) in the positive and negative electrospray ionization (ESI), showed unique chemical profile for each species that can be useful for species identification and quality control of herbal drug formulations. R. vesicarius was characterized by abundances of flavonoids and R. dentatus was abundant in anthraquinones and chromones.
Bioactive Chemical Constituents of a Sterile Endophytic Fungus from Meliotus dentatus
Hidayat Hussain,Karsten Krohn,Siegfried Draeger,Kathrin Meier
Records of Natural Products , 2009,
Abstract: Chemical and biological investigations of the endophytic fungus of an unidentifiedAscomycete, isolated from Meliotus dentatus led to the isolation of six known polyketide metabolites (1–6) andtwo steroids (7 and 8). Compounds 1–3, and 5 were tested for antibacterial, antialgal and antifungal activities.Compounds 2, 3, and 5 showed good activity against the alga Chlorella fusca, while compounds 2 and 3 wereactive against the Gram negative bacterium Escherichia coli and compounds 3 and 5 also against the Grampositive Bacillus megaterium. Similarly, compounds 3 and 5 also showed antifungal activity againstMicrobotryum violaceum.
褐牙鲆、夏鲆及其杂交子代核型与DAPI 带型分析  [PDF]
隋娟,马道远,肖志忠,徐世宏,肖永双,武宁宁,刘清华,李军
海洋科学 , 2014, DOI: 10.11759/hykx20130814004
Abstract: 为了深入剖析褐牙鲆与夏鲆杂交后代的染色体结构,本研究利用秋水仙素-低渗-空气干燥法制备胚胎染色体和DAPI(4’,6’-diamidino-2-phenylindole)荧光染色的方法,对褐牙鲆(Paralichthysolivaceus)、夏鲆(Paralichthysdentatus)及其正反交子代胚胎细胞的染色体组型和染色质的分布进行了研究。结果表明,褐牙鲆、夏鲆及其正交子代(褐牙鲆♀×夏鲆♂)染色体组均含有48条端部着丝粒染色体,染色体组型公式均为2n=48t,组内染色体长度分布连续,三者核型相似。反交子代(夏鲆♀×褐牙鲆♂)为46条端部着丝粒染色体,比亲本及正交子代少了两条染色体。DAPI荧光染色显示,褐牙鲆1号染色体中的一条染色体有较明显的次缢痕,夏鲆及正反交子代染色体中未见明显次缢痕。褐牙鲆与正交子代染色体着色较为均一,而夏鲆与反交子代着丝粒区域亮度明显增强。
Nutritional analyses of Rumex hastatus D. Don, Rumex dentatus Linn and Rumex nepalensis Spreng
I Hameed, G Dastagir
African Journal of Biotechnology , 2009,
Abstract: The study shows the presence of moisture, ash, crude fiber, proteins, fats and oils, and carbohydrates in proximate percentage in Rumex hastatus, Rumex dentatus and Rumex nepalensis (Family Polygonaceae).
Ambicolored specimens of the flounder Paralichthys orbignyanus (Pleuronectiformes: Paralichthyidae)
Carnikián, Agustín;Acu?a, Alicia;Viana, Federico;
Neotropical Ichthyology , 2006, DOI: 10.1590/S1679-62252006000200015
Abstract: two ambicolored specimens of paralichthys orbignyanus were reported for the estuarine area of the arroyo pando (uruguay). one of the specimens showed an almost fully coloration on the blind side, excepting the cephalic region, while the other one was partially pigmented. this is the first record of ambicoloration in p.orbignyanus.
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