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831.
As part of the development of a management program for Nile crocodiles in Lake Nasser, Egypt, we used a dependent double-observer sampling protocol with multiple observers to compute estimates of population size. To analyze the data, we developed a hierarchical model that allowed us to assess variation in detection probabilities among observers and survey dates, as well as account for variation in crocodile abundance among sites and habitats. We conducted surveys from July 2008–June 2009 in 15 areas of Lake Nasser that were representative of 3 main habitat categories. During these surveys, we sampled 1,086 km of lake shore wherein we detected 386 crocodiles. Analysis of the data revealed significant variability in both inter- and intra-observer detection probabilities. Our raw encounter rate was 0.355 crocodiles/km. When we accounted for observer effects and habitat, we estimated a surface population abundance of 2,581 (2,239–2,987, 95% credible intervals) crocodiles in Lake Nasser. Our results underscore the importance of well-trained, experienced monitoring personnel in order to decrease heterogeneity in intra-observer detection probability and to better detect changes in the population based on survey indices. This study will assist the Egyptian government establish a monitoring program as an integral part of future crocodile harvest activities in Lake Nasser. © 2012 The Wildlife Society.  相似文献   
832.
Few studies have been published on the feeding ecology of Japanese soil fauna based on stable isotope analysis. Therefore, the present work aims to use this technique for studying the trophic structure of Japanese soil fauna at two coniferous forests. Significant differences were observed between investigated sites (Arahama and Gamo) in genus richness and abundance, while for Shannon diversity indexes the difference was non-significant. The isotopic signatures (δ13C and δ15N) of the invertebrates collected at Arahama ranged from 0.3 to 6.3‰ for δ15N and from −27.3 to −23.3‰ for δ13C. At Gamo, invertebrates δ13C values ranged from −26.1 to −23.5‰ and δ15N values ranged from 1.6 to 6.8‰. At both sites, invertebrates formed two distinct groups on the basis of combined C and N stable isotope ratios. The locations of these groups related to δ13C values. The less enriched group (δ13C < −25‰) and the more enriched one (δ13C > −25‰). The range of δ15N for the present animals exceeded two trophic levels. While, the gradual 15N enrichment within the invertebrates species may indicate the dominance of omnivory in soil food webs. The differences between sites in δ15N confirm the importance of studying the trophic structure of soil fauna locally.  相似文献   
833.
Abstract

Aspergillus flavus is a phytopathogenic fungus that produces toxic compounds, aflatoxins, in infected plant tissues which harm human and animal health. In this study, 57 food/feed products were collected from 9 locations in Aseer, KSA. A total of 93 isolates were recovered from the samples and were identified as Aspergillus spp. based on their cultural and microscopic characteristics. Six isolates (Af3, Af23, Af24, Af26, Af45 and Af48) were selected and confirmed as A. flavus using polymerase chain reaction (PCR), sequencing of ITS1-5.8s-ITS2 rDNA region and phylogenetic analyses. The six sequences were deposited in the GenBank under the accession numbers of KU561932, KU561934, KU561935, KU561936, KU561937 and KU561938, respectively. Random amplification of polymorphic DNA (RAPD-PCR) of the six isolates using five primers (OPA-2, OPA-3, OPA-9, OPA-11 and OPA-15), produced polymorphic DNA bands of 12, 36, 25, 1 and 1, respectively. The band sizes ranged from 130 to 1600?bp, whereas no monomorphic bands were observed. The bio-control of the six selected A. flavus isolates using three locally isolated yeasts (Candida davisiana, Rhodotorula graminis and Exophiala dermatitidis) was assessed. On solid media, the three yeast strains inhibited all tested A. flavus isolates. The most effective yeast strain was R. graminis. In liquid media, both yeast strains C. davisiana and R. graminis inhibited the dry weights of the six A. flavus isolates. Bio-control approaches of A. flavus could help controlling the pathogen, ultimately, reduce the risk of aflatoxins in human and animal supplies and reduce the use of chemicals that affect the environment and health.  相似文献   
834.
Molecular Biology Reports - Because of low sensitivity and specificity of the currently available urine biomarkers of bladder cancer (BC) detection and painful cystoscopy procedure. Our study aimed...  相似文献   
835.
Phytochemistry Reviews - There are approximately 260 known species in the genus Millettia, many of which are used in traditional medicine to treat human and other animal ailments in various parts...  相似文献   
836.
Cisplatin is one of the most potent and effective chemotherapeutic agents. However, its antineoplastic use is limited due to its cumulative nephrotoxic side effects. Therefore, the present study was undertaken to examine the nephroprotective potential of dietary bee honey and royal jelly against subchronic cisplatin toxicity in rats. Male Wistar rats were randomly divided into controls, cisplatin-treated, bee honey-pretreated cisplatin-treated and royal jelly-pretreated cisplatin-treated groups. Bee honey and royal jelly were given orally at doses of 20 and 100 mg/kg, respectively. Subchronic toxicity was induced by cisplatin (1 mg/kg bw, ip), twice weekly for 10 weeks. Cisplatin treated animals revealed a significant increase in serum level of renal injury products (urea, creatinine and uric acid). Histopathologically, cisplatin produced pronounced tubulointerstitial injuries, upregulated the fibrogenic factors, α-smooth muscle actin (α-SMA) and transforming growth factor β1(TGF-β1), and downregulated the cell proliferation marker, bromodeoxyuridine (Brdu). Dietary bee honey and royal jelly normalized the elevated serum renal injury product biomarkers, improved the histopathologic changes, reduced the expression of α-SMA and TGF-β1 and increased the expression of Brdu. Therefore, it could be concluded that bee honey, and royal jelly could be used as dietary preventive natural products against subchronic cisplatin-induced renal injury.  相似文献   
837.
Russian Journal of Plant Physiology - Vicia faba (L.) is a valuable grain legume, rich in nutrients and bioactive constituents with large genotypic variability in&nbsp;resistance to abiotic...  相似文献   
838.
The regulation by immune checkpoint is able to prevent excessive tissue damage caused by ischemia reperfusion (I/R); therefore, the study aims to investigate the behavior of phosphoprotein associated with glycosphingolipid-enriched microdomains 1 (PAG1) mRNA, miR-1206 and small nucleolar RNA host gene 14 (SNHG14) during I/R and intake of pentoxifylline (PTX) as a protective drug. The relative expression level of PAG1/miR-1206/SNHG14 was determined by qRT-PCR. Cardiac tissue levels of cytotoxic T-lymphocyte associated antigen 4 (CTLA4) and PAG1 protein expression were determined by ELISA technique. The regulatory T cells achieved by the flow cytometry. The results found that the relative expression of SNHG14 was significantly upregulated in I/R, but suppressed in PTX treated groups with enhancement of the relative expression level of miR-1206. The gene and protein expression of PAG1 were downregulated with effective doses of PTX. The results showed that (30 and 40 mg/kg bwt) PTX dose suppressed the CTLA4 development significantly. The mean of the regulatory T cell in PTX protective groups is significantly reduced at (p < 0.001) in a comparison with I/R group. Spearman's correlation analysis revealed a significant negative correlation between SNHG14 and miR-1206, but a significant positive correlation between SNHG14 and PAG1 in I/R heart tissue. The results indicated that miR-1206 and SNHG14 can be used as biomarkers with perfect sensitivity and specificity. Using PTX reduced cardiac tissue damage. SNHG14 and miR-1206 can be used as a diagnostic tool in I/R.  相似文献   
839.
The present study describes the biosynthesis of silver nanoparticles, using the fungus Penicillium verrucosum. The silver nanoparticles were synthesised by reacting silver nitrate (AgNO3) with the cell free filtrates of the fungal culture, and were then characterized by UV–visible spectroscopy, transmission electron microscopy, scanning electron microscopy, energy-dispersive, and X-ray diffraction analysis to further evaluate their successful biosynthesis, optical and morphological features (size and shape), and crystallinity. The bioactivity of the synthesized nanoparticles against two phytopathogenic fungi i.e: Fusarium chlamydosporum and Aspergillus flavus was evaluated using nanomaterial seeding media. These biogenic silver nanoparticles were polydisperse in nature, with a size of 10–12 nm. With regard to the antifungal activity, 150 ppm of the nanoparticles suppressed the growth of F. chlamydosporum and A. flavus by about 50%. To the best of our knowledge, this is the first report on the use of P. verrucosum to synthesise silver nanoparticles. The present study demonstrates a novel, simple, and eco-friendly process for the generation of biofunctionally useful biogenic nanoparticles.  相似文献   
840.
Abstract

In this study, the decolorization efficiency of seven microalgae isolates; Nostoc muscorum, Nostoc humifusum, Spirulina platensis, Anabaena oryzae, Wollea saccata, Oscillatoria sp. and Chlorella vulgaris was investigated for dye decolorization. The highest decolorization percentages of Brazilwood, Orange G, and Naphthol Green B dyes (99.5%, 99.5%, and 98.5%, respectively) were achieved by Chlorella vulgaris. However, the maximum efficiency for dye decolorization percentages of CV and malachite green dyes were exhibited by A. oryzae (97.4%) and W. saccata (93.3%). Ligninolytic enzymes activity assay was carried out for laccase and lignin peroxidase enzymes, which revealed a high efficiency of the C. vulgaris, A. oryzae and W. saccata to lignin containing compound degradation. The highest laccase production recorded by C. vulgaris with Brazilwood, Orange G, and Naphthol Green B dyes (665.0, 678.6, and 659.5?U/ml, respectively). Similarly, C. vulgaris gave a high lignin peroxidase enzyme production with the above three dyes respectively (306.00, 298.34, and 311.45?U/ml). In addition, A. oryzae and W. saccata showed the highest production of the laccase enzyme (634.6 and 577.45?U/ml, respectively) with CV and malachite green dyes. The degradation products have been characterized after decolorization and verified using FTIR analysis. The high decolorization percentages achieved by C. vulgaris, A. oryzae and W. saccata make them potential candidates for bioremediation and pre-processing to remove dyes from textile effluents.  相似文献   
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