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Sebahattin Özcan Cafer S. Sevimay Mustafa Yildiz Cengiz Sancak Murat Özgen 《Plant cell reports》1996,16(3-4):200-203
Summary Immature cotyledons and embryo axes of sainfoin were cultured on Murashige and Skoog (MS) media supplemented with various concentrations of 6-benzylaminopurine (BAP) and a-naphthaleneacetic acid (NAA) to induce adventitious shoot regeneration. The highest frequency of shoot regeneration occurred following an initial callus growth on a MS medium containing 0.5 mg/l BAP and 2 mg/l NAA. Immature embryo axes showed higher regeneration capacity than immature cotyledons, however, shoot elongation was best achieved on immature cotyledons. Regenerated shoots were excised and rooted in half strength MS medium with 1 mg/l indole-butyric acid (IBA) or 1 mg/l NAA. The rooted plantlets were finally transferred to compost. 相似文献
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Pascal Mège Anders Ödeen Marc Théry Damien Picard Jean Secondi 《Evolutionary biology》2016,43(1):109-118
Ultraviolet (UV) vision exists in several animal groups. Intuitively, one would expect this trait to be favoured in species living in bright environments, where UV light is the most present. However, UV sensitivity, as deduced from sequences of UV photoreceptors and/or ocular media transmittance, is also present in nocturnal species, raising questions about the selective pressure maintaining this perceptual ability. Amphibians are among the most nocturnal vertebrates but their visual ecology remains poorly understood relative to other groups. Perhaps because many of these species breed in environments that filter out a large part of UV radiation, physiological and behavioural studies of UV sensitivity in this group are scarce. We investigated the extent of UV vision in Caudata, the order of amphibians with the most nocturnal habits. We could recover sequences of the UV sensitive SWS1 opsin in 40 out of 58 species, belonging to 6 families. In all of these species, the evidence suggests the presence of functional SWS1 opsins under purifying selection, potentially allowing UV vision. Interestingly, most species whose opsin genes failed to amplify exhibited particular ecological features that could drive the loss of UV vision. This likely wide distribution of functional UV photoreceptors in Caudata sheds a new light on the visual ecology of amphibians and questions the function of UV vision in nocturnal animal species. 相似文献
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The effects of different cycles of starvation and re‐feeding on growth and body composition in rainbow trout (Oncorhynchus mykiss,Walbaum, 1792)
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O. Taşbozan Y. Emre M. A. Gökçe C. Erbaş F. Özcan E. Kıvrak 《Zeitschrift fur angewandte Ichthyologie》2016,32(3):583-588
This study was designed to investigate the effects of starvation and re‐feeding cycles on the growth performance and body chemical composition of Oncorhynchus mykiss juveniles. A total of 360 juveniles with initial mean weights (IW) of 8.46 ± 0.07 g (n = 360) were stocked into 400‐L tanks in triplicate for each group, with 30 juveniles per tanks. The control group received regular feed, as is the common practice. The three other groups were periodically starved: 1 day starvation followed by 6 days re‐feeding (S1), 2 days starvation followed by 5 days re‐feeding (S2) and 3 days starvation followed by 4 days re‐feeding (S3). The experiment lasted for 10 weeks, over the course of which the water flow rate was 4 L min?1 and the water quality parameters determined as: temperature 14.4 ± 1.1°C, oxygen 8.2 ± 0.4 mg L?1 and pH 7.5 ± 0.2. At the end of the study, S1 had the best growth performance (final weight, specific growth rate, average daily growth) of all test groups (P < 0.05). The lowest daily feed intake (DFI) and growth performance parameters were observed in S3 (P < 0.05), while protein efficiency ratio (PER), net protein utilization (NPU) and lipid efficiency ratio (LER) were higher in the S3 fish group than in the other groups (P < 0.05). Whole body protein and lipid contents were highest in S1 fish. The hepatosomatic index (HSI) and viscerosomatic index (VSI) were significantly different among groups (P < 0.05). Feed conversion ratio (FCR) was significantly lower in starvation groups S1, S2 and S3 than in the control (P < 0.05). Compensation coefficient (CC) values were higher than 1 in all starvation groups. The concluding indicate that rainbow trout exposed to 1 and 2 days of starvation in week cycles could achieve over compensation compared to the control. Additionally, partial growth compensation and improved feed utilization could be achieved in a starvation group within 3 days in a week, by beginning with the juvenile size over a 10‐week experimental period. 相似文献
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Russian Journal of Genetics - Common bean (Phaseolus vulgaris L.), besides being an agricultural product that can be consumed as fresh vegetable, is a significant legume widely being planted in... 相似文献
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Ilkay Orhan Berrin Özçelik Sinem Aslan Murat Kartal Taner Karaoglu Bilge Şener Salih Terzioglu M. Iqbal Choudhary 《Phytochemistry Reviews》2007,6(1):189-196
Purpose of the present study was to evaluate antioxidant, antibacterial, antifungal, and antiviral activities of the petroleum
ether, chloroform, ethyl acetate and methanol extracts as well as the alkaloid fraction of Lycopodium clavatum L. (LC) from Lycopodiaceae growing in Turkey. Antioxidant activity of the LC extracts was evaluated by 1,1-diphenyl-2-picrylhydrazyl
(DPPH) radical-scavenging method at 0.2 mg/ml using microplate-reader assay. Antiviral assessment of LC extracts was evaluated
towards the DNA virus Herpes simplex (HSV) and the RNA virus Parainfluenza (PI-3) using Madin-Darby Bovine Kidney (MDBK) and Vero cell lines. Antibacterial and antifungal activities of the extracts
were tested against standard and isolated strains of the following bacteria; Escherichia coli, Pseudomonas aeruginosa, Proteus mirabilis, Acinobacter baumannii, Klebsiella pneumoniae, Staphylococcus aureus, Bacillus subtilis as well as the fungi; Candida albicans and C. parapsilosis. All of the extracts possessed noteworthy activity against ATCC strain of S. aureus (4 μg/ml), while the LC extracts showed reasonable antifungal effect. On the other hand, we found that only the chloroform
extract was active against HSV (16–8 μg/ml), while petroleum ether and alkaloid extracts inhibited potently PI-3 (16–4 μg/ml
and 32–4 μg/ml, respectively). However, all of the extracts had insignificant antiradical effect on DPPH. In addition, we
also analyzed the content of the alkaloid fraction of the plant by capillary gas chromatography-mass spectrometry (GC-MS)
and identified lycopodine as the major alkaloid. 相似文献
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The morphology, anatomy and distribution of glandular trichomes on the aerial organs of Salvia argentea L. has been investigated. Two morphologically distinct types of glandular trichomes were determined. Capitate glandular trichomes
forming a base 1–7 celled, a stalk 1–5 celled or no stalk and a head uni- or bicellular had various types. In capitate trichomes,
the neck cell that has an important role especially for xeroformic plants, acting to prevent the backflow of secreted substance
through the apoplast has been distinctively observed in the investigated species. The capitate trichomes were present abundantly
on all aerial organs of S. argentea. Peltate glandular trichomes had a large secretory head forming 1–5, 8 central and 8–10, 12, 14 peripheral cells. Peltate
trichomes are present on all aerial organs, except petiole, being the most abundant on calyx and corolla. Results were shown
by tables and photographs. 相似文献
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Bülent Yılmaz Musa H Asyalı Eren Arıkan Sinan Yetkin Fuat Özgen 《Biomedical engineering online》2010,9(1):39