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91.
Mohammad T Ridha 《Aquaculture Research》2004,35(11):1031-1038
The reproductive performance and seed production of three mouth‐brooding tilapia species, Oreochromis spilurus (Günther), Oreochromis aureus (Steindachner) and Taiwanese red tilapia hybrid, were compared in low‐salinity underground water (3–5 g L?1) to select species with the highest reproductive rate. Two‐year‐old males and females having average body weights of 454 and 259 g, respectively, were stocked in 2‐m3 fibreglass breeding tanks (two tanks per species) at 1:3 male to female sex ratio and at average density of three fish m?2. Seeds (unhatched eggs; yolk‐sac fry and the swim‐up fry) were collected weekly for 112 days. The results showed O. spilurus to have significantly higher (P<0.05) mean spawning parameters expressed as total seed tank?1 (84 154), seed kg female?1 day?1 (284), seed m?2 day?1 (190.3) and seed female?1 day?1 (76.3), than O. aureus and red tilapia. Monthly seed production in O. spilurus and red tilapia gradually increased from May, peaked in July and declined in August, while in O. aureus, it continued to decrease from May to August. In this study, the observed production levels of seed in O. spilurus were among the highest levels reported for tilapia; therefore, O. spilurus could be selected as a potential candidate for mass seed production in commercial tilapia hatcheries. 相似文献
92.
David E. Kime Mohammad A. S. Abdullah Miroslawa Sokolowska-Mikolajczyk Piotr Epler 《Fish physiology and biochemistry》1994,13(4):317-324
Carp ovarian tissue was incubated with 3H-17-hydroxyprogesterone in the presence of 0, 0.1, 1, 10, and 100 μg ml−1 unlabeled 17-hydroxyprogesterone. The pattern of metabolites formed showed a marked variation with substrate concentration.
Formation of glucuronide and sulphate conjugates was important only at low substrate concentration. At high substrate concentration
(10 and 100 μg ml−1) 17,20α-dihydroxy-4-pregnen-3-one was the major metabolite, but at intermediate concentrations polar 7α-hydroxypregnanetetrols
predominated. The results support the hypothesis that at low substrate concentrations conjugating, 5α-reducing and 7α-hydroxylating
enzymes, of high activity but low capacity, act as scavengers to deactivate any steroids formed during the relatively low
pituitary gonadotrophin secretions which are necessary for oocyte development, but that during the prespawning gonadotrophin
surge when high levels of substrate are present these enzymes are saturated and 17,20α-dihydroxy-4-pregnen-3-one (17,20αP)
becomes the major ovarian steroid. The possible role of 17,20αP during oocyte final maturation requires further examination. 相似文献
93.
Soumitra Paul Nusrat Ali Swapan K Datta Karabi Datta 《Plant foods for human nutrition (Dordrecht, Netherlands)》2014,69(3):203-208
Low level of iron in staple food crops is one reason for the predominance of iron-deficiency anemia in developing countries. Most of the iron in rice grains accumulates in the outer aleurone layer and embryo, which are removed during milling, and the edible endosperm contains very low amounts of iron. In an effort to increase iron nutrition, we report here the transgene introgression of a high-iron trait into a high-yielding indica rice cultivar. The ferritin gene from soybean (soyfer1) was introduced into rice plants through interbreeding between soybean ferritin-overexpressing transgenic IR68144 and the high-yielding cultivar Swarna. The stable integration of the soyfer1 gene was confirmed in the BC2F4 generation, and the hybrid seeds showed 2.6-fold soybean ferritin gene expression over the recurrent parent Swarna. The hybrid milled seeds revealed a 2.54-fold increase in iron and 1.54-fold increase in zinc compared to Swarna. Agronomic data and an SSR marker analysis of the hybrid rice plants were taken into account for NIL character identification. 相似文献
94.
研究不同时期斑茅产量及其化学组分的变化。结果表明:斑茅生物质产量在11月达到最高,其后开始下降;整个生长发育过程中茎叶生物质产量比呈现上升趋势;含水量随生长发育的进行显著降低;叶片灰分含量全年最低为5月,从10月份开始显著增加,至12月份达到最高。茎秆灰分含量略低于叶片,全年最低为10月,最高为7月,变化幅度不大。叶片中木质素含量全年由高到低排列顺序为12月11月9月10月7月8月6月;茎秆中木质素含量全年由高到低排列顺序为12月11月9月7月8月10月6月。10月份茎秆含水量低,灰分含量最低,热值较高,结合产量和燃料品质考虑其更适于直接燃烧,而9月份叶片则更加适于作为生物转化的材料。 相似文献
95.
F. Hajiani A. A. Ghareaghaji Ali. A. A. Jeddi S. H. Amirshahi F. Mazaheri 《Fibers and Polymers》2014,15(9):1966-1976
In view of the interest in wicking properties of these flexible structures, analysis of the wicking phenomena in nylon 6.6 nanofiber yarns is carried out by considering the twist rate effects. A novel method is used based on adding a pH-sensitive dye to yarn interstructure and the analysis of color alteration of nanofiber yarn structure, resulting from a shift in pH, during the capillary rise of distilled water. The results show that the addition of pH- sensitive dye has no influence on the average nanofiber diameter and the wicking behavior of yarns. This study shows that in short durations, the kinetic of the capillary rise follows the Lucas-Washburn equation. The Lambertw, a mathematical function, has been incorporated, which helps measure an equivalent structural factor of nanofiber yarns and vertical wicking height at any given time considering the gravitational effects. The statistical results show that the average of equilibrium wicking height and capillary rise rate coefficient tend to decrease with increasing the nanofiber yarn twist, due to the reduction of continuity and size of capillaries. 相似文献
96.
N,N-Diethyl-m-toluamide (DEET) is widely used as an insect-repellent. Sulfonamides are an important class of anti-bacterial drugs. In order to combine the strength of anti-bacterial activities of sulfonamides and insect-repellent property of DEET, three azo reactive dyes were designed and synthesized. To do this, the diazoniom salts of sulfonamides viz. 4-amino-N-(4-methyl-2-pyrimidinyl) benzene sulfonamide, 4-amino-N-(4-dimethyl-2-pyrimidinyl) benzene sulfonamide and 4-amino-N-(4,6-dimethyl-2-pyrimidinyl) benzene sulfonamide were prepared using HCl and NaNO2. The resulting diazoniom salts were then coupled to the coupling component containing N,N-diethyl-m-toluamide to produce the novel dyes. The synthesized dyes were filtered off and then purified. To investigate and analyze the dyes, analytical methods such as 1H-NMR, FTIR, UV-visible spectroscopy, and elemental analysis were used. Consequently, the anti-bacterial activities of dyes were measured with E. coli and P. aeruginosa as a Gram-negative strain and S. aureus and S. mutans as a Gram-positive strain according to MIC method. The insect-repellent efficacy of the dyes was studied using standard methods for Anophle mosquito repellent. The results confirmed anti-bacterial and insect-repellent activity of the dyes. 相似文献
97.
Marine sponges belonging to the phylum Porifera (Metazoa), evolutionarily the oldest animals are the single best source of marine natural products. The present review presents a comprehensive overview of the source, taxonomy, country of origin or geographical position, chemical class, and biological activity of sponge-derived new natural products discovered between 2001 and 2010. The data has been analyzed with a view to gaining an outlook on the future trends and opportunities in the search for new compounds and their sources from marine sponges. 相似文献
98.
Anabat Mohammad Mohebi Sheidai Masoud Riahi Hossein Koohdar Fahimeh 《Genetic Resources and Crop Evolution》2022,69(2):855-870
Genetic Resources and Crop Evolution - The genus Crocus of the family Iridaceae is a monophyletic genus with over 100 species. Due to the high degree of hybridization and the changes in the number... 相似文献
99.
Fayaz Humara Mir Asma Hamid Tyagi Sandhya Wani Aijaz A. Jan Nelofar Yasin Mohammad Mir Javid Iqbal Mondal Biswajit Khan Mohd Anwar Mir Reyazul Rouf 《Genetic Resources and Crop Evolution》2022,69(3):1193-1205
Genetic Resources and Crop Evolution - Cicer arietinum L. (chickpea) is one of the most significant legume crops domesticated in the Fertile Crescent. This study was aimed to characterize a diverse... 相似文献
100.
Shahsavari Shiva Noormohammadi Zahra Sheidai Masoud Farahani Farah Vazifeshenas Mohammad Reza 《Genetic Resources and Crop Evolution》2022,69(3):1207-1217
Genetic Resources and Crop Evolution - The pomegranate (Punica granatum L.) is an ancient fruit plant which has been consumed for its nutritional value and medicinal properties by mankind. Several... 相似文献