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排序方式: 共有218条查询结果,搜索用时 9 毫秒
31.
Sivasankaran TG Udayakumar R Elanchezhiyan C Sabhanayakam S 《Cell biology international》2008,32(2):293-297
The effects of sildenafil citrate with ethanol on the rat testis was studied using scanning electron microscopy. Male Albino rats were divided into 8 groups, each being treated for a maximum of 45 days as follows. In the 4 short-term treatment groups, control rats were administered normal saline orally, whereas experimental animals were fed sildenafil citrate (Viagra) 1 microg/g with 18% ethanol (5 g/kg body weight), which was given orally as a single dose. After 1, 2.5, 4 and 24h the rats were killed. In the 4 long-term treatment groups, daily continuous doses of drug and ethanol with a single dosage were given for 15, 30 and 45 days and the animals killed 4h after the last dosage. Changes in the testis were compared with the normal healthy rat testis. The use of a scanning electron microscope for evaluation of the changes in the testis is more suitable for observation of the surface and morphological shapes of the tissue structures. 相似文献
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Diploid/polyploid syntenic shuttle mapping and haplotype-specific chromosome walking toward a rust resistance gene (Bru1) in highly polyploid sugarcane (2n approximately 12x approximately 115)
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Le Cunff L Garsmeur O Raboin LM Pauquet J Telismart H Selvi A Grivet L Philippe R Begum D Deu M Costet L Wing R Glaszmann JC D'Hont A 《Genetics》2008,180(1):649-660
The genome of modern sugarcane cultivars is highly polyploid ( approximately 12x), aneuploid, of interspecific origin, and contains 10 Gb of DNA. Its size and complexity represent a major challenge for the isolation of agronomically important genes. Here we report on the first attempt to isolate a gene from sugarcane by map-based cloning, targeting a durable major rust resistance gene (Bru1). We describe the genomic strategies that we have developed to overcome constraints associated with high polyploidy in the successive steps of map-based cloning approaches, including diploid/polyploid syntenic shuttle mapping with two model diploid species (sorghum and rice) and haplotype-specific chromosome walking. Their applications allowed us (i) to develop a high-resolution map including markers at 0.28 and 0.14 cM on both sides and 13 markers cosegregating with Bru1 and (ii) to develop a physical map of the target haplotype that still includes two gaps at this stage due to the discovery of an insertion specific to this haplotype. These approaches will pave the way for the development of future map-based cloning approaches for sugarcane and other complex polyploid species. 相似文献
33.
Federico Selvi 《Nordic Journal of Botany》2009,27(2):125-133
The new species Armeria saviana, endemic to an isolated mountain chain of the Tyrrhenian Antiappennine system in south Tuscany, central Italy, is described and illustrated. The plant is diploid with 2n=18. It can be distinguished from the related species A. denticulata (Bertol.) DC and A. canescens (Host) Ebel, mainly by leaf characters, capitula, bracts and flowers. The systematic position of the controversial taxon A. majellensis Boiss. subsp. ausonia F. Bianchini, to which the new species has formerly been assigned by some authors, is discussed. A lectotype for A. denticulata is designated. 相似文献
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In this study, we comparatively investigated three endemic Salvia species spreading in Erzincan (Turkey) in terms of anatomy and micromorphology. For anatomical investigation, cross sections taken from stems and leaves of the species were examined under light microscope. For micromorphological investigation, epidermal surface and nutlet structure were examined using scanning electron microscopy. The S. euphratica and S. divaricata species were examined anatomically and micromorphologically for the first time, and S. hypargea was examined micromorphologically for the first time. In anatomical examinations, it was seen that stem and leaf structures of the species were similar. In micromorphological analyses, it has been seen that hairiness of the nutlet surface and nutlet ornamentations (verrucate and rugose type) created a difference between the species. 相似文献
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A. Selvi Jaseetha Abdul Salam Nilanjana Das 《World journal of microbiology & biotechnology》2014,30(11):2839-2850
Cefdinir, a semi-synthetic third generation cephalosporin antibiotic being considered as an emerging pollutant, demands removal from aquatic ecosystems. A yeast strain isolated from pharmaceutical wastewater which was identified as Ustilago sp. SMN03 by molecular techniques and was found to be capable of utilizing cefdinir as a sole carbon source. The isolate was found to degrade 81 % of cefdinir within 6 days under optimized conditions viz. pH 6.0, temperature 30 °C, a shaking speed of 120 rpm, an inoculum dosage of 4 % (w/v) and an initial cefdinir concentration of 200 mg L?1. Kinetic studies revealed that cefdinir degradation followed the pseudo-first order model, a rate constant of 0.222 per day and a half-life period of 3.26 days. Using LC–MS analysis, six novel intermediates formed during the cefdinir degradation were identified and characterized. FT-IR analysis showed that the functional groups ranging from 1,766 to 1,519 cm?1, characteristic for lactam ring were completely removed during the cefdinir degradation. The opening of the β-lactam ring was one of the major steps in the cefdinir degradation process. Based on the results from the present study, a possible pathway of cefdinir degradation by Ustilago sp. SMN03 was proposed. To the best of our knowledge, this is the first report on microbial degradation of cefdinir by yeast. 相似文献
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Kalai Selvi Palaniswamy Vijaya Padma Vishwanadha Saranya Ramalingam Singaravelu 《Cell stress & chaperones》2014,19(3):409-419
Humans are systemically exposed to persistent organic pollutants, of which 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) has become a major environmental concern. Exposure to TCDD results in a wide variety of adverse health effects which is mediated by oxidative stress through CYP1A1 activation and arachidonic acid metabolites. Eicosapentaenoic acid (EPA) exhibits antioxidant property and competes with arachidonic acid in membrane phospholipids and produces anti-inflammatory EPA derivatives. Since both EPA and its derivatives have been reported to enhance the antioxidant mechanism, the present study aimed at studying whether EPA could offer protection against TCDD-induced oxidative stress and nephrotoxicity in Wistar rats. Estimation of kidney markers (serum urea and creatinine) and histopathological studies revealed that EPA treatment significantly reduced TCDD-induced renal damage. TCDD-induced oxidative damage was reflected in a significant increase in CYP1A1 activity and lipid peroxide levels with a concomitant decline in non-enzymic antioxidant (GSH) and various enzymic antioxidants such catalase (CAT), superoxide dismutase (SOD), glutathione-S-transferase (GST), and glutathione peroxidase (GPx). In addition, TCDD-induced oxidative stress also resulted in decline in Na+-K+ and Mg2+ATPases activities with increase in Ca2+ ATPases activity. Oral treatment with EPA showed a significant cytoprotection against TCDD-induced renal oxidative stress by decreased CYP1A1 activity and enhanced antioxidant status. TCDD-induced alterations in ATPase enzyme activities were also prevented by EPA treatment. Our results show clear evidence that EPA ameliorates TCDD-induced oxidative stress and kidney damage; thus suggest the potential of EPA as an effective therapeutic agent against toxic effects mediated through redox imbalance. 相似文献