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81.
Antigen B (AgB) is a major protein produced by the metacestode cyst of Echinococcus granulosus, the causative agent of cystic hydatid disease. E. granulosus AgB is a gene family of at least five gene loci (B1-B5), each one consisting of several minor variants. We used PCR-SSCP followed by DNA sequencing to evaluate sequence variation and polymorphism of AgB1 in 99 isolates which the 43 were from cattle, 25 of sheep and 31 of human. All samples were analyzed with 12S rRNA-PCR for the strain detection and all of were identified as G1-G3 cluster (E. granulosus sensu stricto). The 16 human, 35 cattle and 25 sheep isolates were yielded the 102 bp band by PCR and these samples were tested by SSCP. As results of the SSCP, different band profiles were detected one each of cattle and human isolates while the other 74 isolates showed same band patterns. The DNA sequence analysis was performed for these two isolates and the other selected 4 isolates and polymorphism was confirmed. 相似文献
82.
Qablan MA Sloboda M Jirků M Oborník M Dwairi S Amr ZS Hořín P Lukeš J Modrý D 《Veterinary parasitology》2012,186(3-4):456-460
DNA of two species of piroplasmids was detected in dromedaries during a survey of blood protozoans in Jordan between 2007 and 2009. Ten clinically healthy camels (10%) originating from three Jordanian districts were found, using a PCR assay, to harbor Theileria or Babesia species in their blood and no mix infection was determined. Analysis of the partial 18S rRNA gene sequences of these parasites allowed their unambiguous identification as equine piroplasmids Babesia caballi (n=6) and Theileria equi (n=4). In case of latter species, a novel genotype was found in horses. This first molecular-based species determination of piroplasmids from camels further contributes to the growing evidence of low host specificity of piroplasmids. 相似文献
83.
Small-scale Forestry - Ageing, urbanization, and decreasing dependence of non-industrial private forest (NIPF) owners on forestry income have challenged the industrial timber supply of several... 相似文献
84.
85.
Ghanbarpour Reza Sami Masoud Salehi Mahmood Ouromiei Mahla 《Tropical animal health and production》2011,43(1):153-157
The purposes of this study were to determine the phylogenetic background and the virulence gene profiles of Escherichia coli isolates from colisepticemic and feces of healthy (AFEC) broiler chickens. In this study, 253 E. coli isolates including 141 avian pathogenic E. coli (APEC) and 112 AFEC isolates were examined by PCR. In general, 253 E. coli isolates distributed among group A (51.8%), B1 (15.8%), B2 (8.7%), and D (23.7%). Ten (8.9%) AFEC isolates segregated in
to B1 phylo-group and 102 (91.1%) isolates fell into six different phylogenetic subgroups. Distribution of colisepticemic
and fecal isolates differed significantly in their assignments to A and B1 phylo-groups. The three most prevalent virulence
genes were crl, fimH, and aer in isolates between both groups. The four genetic markers aer, papC, afa, and sfa were detected significantly more often among colisepticemic isolates than in fecal isolates from healthy broilers. The presence
of stx
2
gene in fecal isolates were significantly differs among the colisepticemic isolates. F17 fimbrial family encoding gene and
eae gene were detected in APEC and AFEC isolates, respectively. The colisepticemic and fecal isolates possessed the virulence
genes were detected in all of the four phylogenetic groups. Several combination patterns of the virulence genes were detected
in APEC and AFEC isolates. In colisepticemic isolates the combination of aer, crl, and fimH genes was the most prevalent pattern. None of the examined isolates harbored the cdt, cnf1, ipaH, and stx
1
virulence gene sequences. 相似文献
86.
87.
Picard C Puel A Bonnet M Ku CL Bustamante J Yang K Soudais C Dupuis S Feinberg J Fieschi C Elbim C Hitchcock R Lammas D Davies G Al-Ghonaium A Al-Rayes H Al-Jumaah S Al-Hajjar S Al-Mohsen IZ Frayha HH Rucker R Hawn TR Aderem A Tufenkeji H Haraguchi S Day NK Good RA Gougerot-Pocidalo MA Ozinsky A Casanova JL 《Science (New York, N.Y.)》2003,299(5615):2076-2079
Members of the Toll-like receptor (TLR) and interleukin-1 receptor (IL-1R) superfamily share an intracytoplasmic Toll-IL-1 receptor (TIR) domain, which mediates recruitment of the interleukin-1 receptor-associated kinase (IRAK) complex via TIR-containing adapter molecules. We describe three unrelated children with inherited IRAK-4 deficiency. Their blood and fibroblast cells did not activate nuclear factor kappaB and mitogen-activated protein kinase (MAPK) and failed to induce downstream cytokines in response to any of the known ligands of TIR-bearing receptors. The otherwise healthy children developed infections caused by pyogenic bacteria. These findings suggest that, in humans, the TIR-IRAK signaling pathway is crucial for protective immunity against specific bacteria but is redundant against most other microorganisms. 相似文献
88.
Sami Rabei Reda M. Rizk Abdel-Hamid A. Khedr 《Genetic Resources and Crop Evolution》2013,60(4):1353-1364
The cultivated varieties and landraces of Cucurbitaceae growing in Egypt are presented, 27 taxa, belonging to three genera, six species, and five subspecies. These characters are arranged according to their usefulness for identifications as follow: fruit characters, seed characters and trichome type. Fruit characters are a good taxonomic tool at varietal level when combined with the other vegetative characters. Two keys to 27 cultivated varieties of Cucurbitaceae (Cucumis, Cucurbita and Luffa) were constructed using the DELTA software system. One key is used for identification, and then the other is used as a confirmatory key. Those keys were built using 36 morphological characters include vegetative, floral, fruit and seed characters. There is a significant correlation between seed size and growth parameters. The growth parameters of the studied taxa included leaf length/size, petiole length and corolla length. There is a highly positive, significant correlation between seed volume and leaf size (r = 0.81831, P ≤ 0.001), seed volume and petiole length (r = 0.79112, P ≤ 0.001), seed volume and leaf length (r = 0.83566, P ≤ 0.001), and seed volume and corolla length (r = 0.59108, P ≤ 0.001). 相似文献
89.
The objective of this work was to identify a new efficiency-driven pumping station regulation aiming at maximum energy savings in on-demand irrigation systems. This objective can be achieved by matching the discharge and the pressure head required by the network (characteristic curve of the network) during an entire irrigation season by regulating the operation of the pumping station on the basis of operating the pumps at maximum efficiency. The characteristic curve of the network can be obtained by using an appropriate stochastic generation and hydraulic model. Additional performance analyses were also carried out using the AKLA model in order to better characterize the hydraulic behavior of the irrigation systems under study. The characteristic curves of the centrifugal pumps were adapted to the network curve by equipping the pumping station with variable-speed devices. Several types of regulation based on variable-speed techniques were identified and analyzed. The energy consumption for each regulation technique was quantified for two on-demand irrigation districts in Southern Italy, managed by the Water Users Organization “Consortium of Capitanata”. It was demonstrated that, in comparison with the current pumping station regulation, maximum energy savings may be achieved when pump regulation is carried out with variable-speed devices to maintain the pumps at maximum efficiency. 相似文献
90.
Meagan Harper Hebah S. Mejbel Dylan Longert Robin Abell T. Douglas Beard Joseph R. Bennett Stephanie M. Carlson William Darwall Anthony Dell Sami Domisch David Dudgeon Jörg Freyhof Ian Harrison Kathy A. Hughes Sonja C. Jähnig Jonathan M. Jeschke Richard Lansdown Mark Lintermans Abigail J. Lynch Helen M. R. Meredith Sanjay Molur Julian D. Olden Steve J. Ormerod Harmony Patricio Andrea J. Reid Astrid Schmidt-Kloiber Michele Thieme David Tickner Eren Turak Olaf L. F. Weyl Steven J. Cooke 《水产资源保护:海洋与淡水生态系统》2021,31(9):2632-2653
- Freshwater biodiversity is declining at an unprecedented rate. Freshwater conservationists and environmental managers have enough evidence to demonstrate that action must not be delayed but have insufficient evidence to identify those actions that will be most effective in reversing the current trend.
- Here, the focus is on identifying essential research topics that, if addressed, will contribute directly to restoring freshwater biodiversity through supporting ‘bending the curve’ actions (i.e. those actions leading to the recovery of freshwater biodiversity, not simply deceleration of the current downward trend).
- The global freshwater research and management community was asked to identify unanswered research questions that could address knowledge gaps and barriers associated with ‘bending the curve’ actions. The resulting list was refined into six themes and 25 questions.
- Although context-dependent and potentially limited in global reach, six overarching themes were identified: (i) learning from successes and failures; (ii) improving current practices; (iii) balancing resource needs; (iv) rethinking built environments; (v) reforming policy and investments; and (vi) enabling transformative change.
- Bold, efficient, science-based actions are necessary to reverse biodiversity loss. We believe that conservation actions will be most effective when supported by sound evidence, and that research and action must complement one another. These questions are intended to guide global freshwater researchers and conservation practitioners, identify key projects and signal research needs to funders and governments. Our questions can act as springboards for multidisciplinary and multisectoral collaborations that will improve the management and restoration of freshwater biodiversity.