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排序方式: 共有937条查询结果,搜索用时 31 毫秒
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Randomized controlled study of a novel triple nitazoxanide (NTZ)‐containing therapeutic regimen versus the traditional regimen for eradication of Helicobacter pylori infection
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916.
Matthew H. Shirley Robert M. Dorazio Ekramy Abassery Amr Abd Elhady Mohammed Saad Mekki Hosni Helmy Asran 《The Journal of wildlife management》2012,76(5):966-975
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
917.
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
918.
Sara H. Daghriri Sulaiman A. Alrumman Abd El-Latif Hesham 《Archives Of Phytopathology And Plant Protection》2013,46(9-10):445-460
AbstractAspergillus 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
919.
El-Shal Amal S. Shalaby Sally M. Abouhashem Safwat E. Elbary Eman H. Abd Azazy Samir Rashad Nearmeen M. Sarhan Walaa 《Molecular biology reports》2021,48(5):4361-4371
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
920.
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