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排序方式: 共有327条查询结果,搜索用时 31 毫秒
11.
Basma M. Sheta Trevon L. Fuller Brenda Larison Kevin Y. Njabo Ahmed Samy Ahmed Ryan Harrigan Anthony Chasar Soad Abdel Aziz Abdel-Aziz A. Khidr Mohamed M. Elbokl Lotfy Z. Habbak Thomas B. Smith 《Veterinary microbiology》2014
Highly pathogenic influenza A virus subtype H5N1 causes significant poultry mortality in the six countries where it is endemic and can also infect humans. Egypt has reported the third highest number of poultry outbreaks (n = 1084) globally. The objective of this cross-sectional study was to identify putative risk factors for H5N1 infections in backyard poultry in 16 villages in Damietta, El Gharbia, Fayoum, and Menofia governorates from 2010–2012. Cloacal and tracheal swabs and serum samples from domestic (n = 1242) and wild birds (n = 807) were tested for H5N1 via RT-PCR and hemagglutination inhibition, respectively. We measured poultry rearing practices with questionnaires (n = 306 households) and contact rates among domestic and wild bird species with scan sampling. Domestic birds (chickens, ducks, and geese, n = 51) in three governorates tested positive for H5N1 by PCR or serology. A regression model identified a significant correlation between H5N1 in poultry and the practice of disposing of dead poultry and poultry feces in the garbage (F = 15.7, p < 0.0001). In addition, contact between domestic and wild birds was more frequent in villages where we detected H5N1 in backyard flocks (F = 29.5, p < 0.0001). 相似文献
12.
Li Shuo Wang Changming Zhang Suoyu Li Tong Khan Kaleem Ullah Jan 《Journal of Soils and Sediments》2022,22(3):782-796
Journal of Soils and Sediments - Compression studies can provide insights into evaluating the engineering potential and environmental impact of clay. The objective of this study was to... 相似文献
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Sabine Chahory DVM Bernard Clerc DVM PhD Patrick Devauchelle DVM Aziz Tnibar DVM PhD 《Journal of Equine Veterinary Science》2002,22(11)
A 7-year-old Selle français gelding was presented for a recurrent conjunctival tumour on the left eye. A previous histologic analysis revealed a conjunctival squamous cell carcinoma. As it was the third recurrence after surgical excision in a 1½-year period, we decided to perform interstitial radiotherapy combined with the surgical excision. Two Iridium-192 pins were implanted in the subcutaneous fascia of the lower eyelid over the tumor site and were removed 3 days later. No postoperative adverse reactions were observed. Twelve months postoperatively, there were no signs of local recurrence. Surgical excision combined with Iridium-192 therapy appeared to be an effective treatment in this case. 相似文献
15.
Diarrhea toxin obtained from a waterbloom-producing species, Microcystis aeruginosA Kützing 总被引:3,自引:0,他引:3
K M Aziz 《Science (New York, N.Y.)》1974,183(130):1206-1207
A diarrhea-producing toxin from a blue-green alga, Microcystis aeruginosa Kützing, was obtained from standing laboratory cultures. The non-dialyzable fraction of the lysate from whole cells produced fluid accumulation in the ligated small intestinal loops in guinea pigs. 相似文献
16.
Shocks in ion sputtering sharpen steep surface features 总被引:1,自引:0,他引:1
Chen HH Urquidez OA Ichim S Rodriquez LH Brenner MP Aziz MJ 《Science (New York, N.Y.)》2005,310(5746):294-297
We report a regime of ion beam sputtering that occurs for sufficiently steep slopes. High slopes propagate over large distances without dissipating the steepest features. Both the propagation velocity and the dynamically selected slope are universal, independent of the details of the initial shape of the surface. The resulting behavior can be understood as the propagation of a shock front that self-selects a stable slope, as has been previously observed in thin-film fluid flows. Experiments confirm predictions of the theory. An important implication of the propagative behavior at high surface slopes is that a pattern can be fabricated at a large length scale and, through uniform ion irradiation, reduced to a smaller length scale while preserving, or even sharpening, the sharpest features. 相似文献
17.
Ullah SM Murphy B Dorich B Richter B Srinivasan K 《Journal of agricultural and food chemistry》2011,59(6):2169-2174
This paper describes a new in-cell method for pursuing accelerated solvent extraction (ASE) prior to lipid analysis from food samples. It is difficult to pursue direct ASE with acid- or base-hydrolyzed samples due to the corrosive nature of the reagents and material limitations. In this study ion exchange based materials were used to remove acid or base reagents in-cell without compromising the recovery of lipids. The performance data are presented here for the new methods for lipid extraction for a variety of food samples and compared to the Mojonnier method. NIST Standard Reference Materials (SRM-1546 and SRM-1849) were used to validate the ASE methods. Excellent fat recoveries were obtained for the ASE methods. The new methods presented here enhance the utility of ASE and eliminate labor intensive protocols. 相似文献
18.
Shoot:root (S:R) response in four winter C3-grasses (cereals) viz. wheat (Triticum aestivum L.), rye (Secale cereale L.), barley (Hordeum vulgare L.) and oats (Avena sativa L.) was investigated under eight different NPK sources (S1 = 20-20-20, S2 = 20-27-5, S3 = 7-22-8, S4 = 10-10-10-20S, S5 = 11-15-11, S6 = 31-11-11, S7 = 24-8-16, and S8 = 19-6-12) in pot experiment at Dryland Agriculture Institute, West Texas A&M University, Canyon, Texas, USA during winter 2009–2010. The experiment was performed in completely randomized design (CRD) with three repeats. The objective of this experiment was to investigate whether the S:R of winter cereals differ or not when applied with different NPK sources. Considerable variations in the shoot: root was noticed in the four grasses at different growth stages, i.e., 30, 60 and 90 days after emergence (DAE) when applied with different NPK fertilizers sources. Wheat had the highest S:R of 3.4 at 30 days after emergence (DAE), barley at 60 DAE (6.5), while oats at 90 DAE (3.9). Among the NPK sources, crops had the highest S:R of 3.6, 6.2 and 3.7 when applied with S3, S2, and S6 at 30, 60 and 90 DAE, respectively. Shoot to root ratio showed positive relationship with increase in shoot weight and negative relationship with increase in root weight. The NPK fertilizer S6 (31: 11: 11), an acid loving fertilizer had negative effects on the shoot and root development of cool season cereals, but among these cereals under study, barley and oats roots were affected more than wheat and rye. It was concluded from this present study, that the four cool season cereals responded differently in terms of shoot: root to different NPK fertilizers at different growth stages. 相似文献
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The effect of dietary selenium (Se) deficiency on the generation of neutrophil chemotactic factors from goat polymorphonuclear leukocytes (PMN) was studied. Polymorphonuclear leukocytes were isolated from 2 groups of crossbred goats. One group (n = 3) was fed a diet deficient in Se; the other (n = 3) was fed a diet adequate in Se. The PMN from each goat were stimulated with calcium ionophore A23187 and supernatants were collected. Each supernatant was immediately assayed for its ability to elicit neutrophil chemotaxis (NCT) and neutrophil chemokinesis by the Boyden chamber technique and neutrophil chemiluminescence (NCL) by the luminol-dependent chemiluminescence assay. Measurements from each group were compared, using the Student's t test. There was no significant difference (P greater than 0.01) in neutrophil chemokinesis elicited by supernatants derived from stimulated PMN from the 2 groups. However, supernatants derived from PMN of goats fed the Se-deficient diet had a significantly decreased capacity (P less than 0.01) to stimulate NCT and NCL. In vitro incubation of PMN with Se before ionophore treatment produced supernatants with increased NCL stimulation (P less than 0.05), but none with increased NCT stimulation (P greater than 0.05). However, both activities were restored after goats fed the Se-deficient diet (P less than 0.01) were given Se subcutaneously. Seemingly, dietary Se deficiency is associated with depressed PMN generation of factors that stimulate NCT and NCL. In contrast to NCL factors, synthesis of factors stimulating NCT probably was not associated directly with PMN glutathione peroxidase concentration. 相似文献