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71.
A study of some sequelae of amputation of the digit using three operative techniques 总被引:1,自引:0,他引:1
M A Osman 《The Veterinary record》1970,87(20):610-615
72.
Laboratory test were carried out on eggs, larvae, nymphs and adults of Hyalomma anatolicum to determine the acaricidal activities of petroleum ether (PE) and crude ethanolic extracts (EE) from the leaves of Guiera senegalensis J.F. Gmel. (Combrataceae) using immersion method.Stock solutions, of 300 mg/ml (30%) of the each two extract, were prepared. Six two-fold serial dilutions each with three replicates were used. Both extracts, at the highest concentration 150 mg/ml (15%), induced 100% failure of hatching of the treated eggs. The concentrations of PE and EE that induced 50% inhibition of the hatchability (IC50) were 1.71 and 0.508%, respectively. In the larval immersion test (LIT), EE at 15% concentration caused complete mortality while the same concentration of PE resulted in 96% mortality. The mortalities increased with concentrations. There was a correlation between the mortalities and increased concentrations, the values of the linear correlation coefficient (r) for PE and EE were 0.93 and 0.79, and The LC50 and LC99 were 2.08 and 14.09, and 0.787 and 11.054, respectively. At the concentrations of 3.75%, 7.5% and 15%, PE inhibited the molting of the nymphs by 40, 55 and 65%, respectively, while EE induced 46.49, 64.3 and 71.4% inhibition, respectively. The effectiveness of the treatment against unfed adult females was assessed by measuring the feeding performance and egg production using adult immersion test (AIT). Although, there was no mortality in unfed adults, PE and EE inhibited feeding and egg-laying of the survived females by 35–100% and 6.16–100%, respectively. Our results indicated that G. senegalensis is a promising biocontrol candidate as an acaricidal agent against H. anatolicum. 相似文献
73.
Preparation, isolation, and characterization of cutin monomers and oligomers from tomato peels 总被引:4,自引:0,他引:4
Osman SF Irwin P Fett WF O'Connor JV Parris N 《Journal of agricultural and food chemistry》1999,47(2):799-802
Cutin in tomato peels was depolymerized in methanolic base to yield cutin monomers or a mixture of cutin oligomers. These products were isolated by typical solvent extraction methods or by precipitation, and the isolates were characterized by chromatographic and spectroscopic analyses. It was determined that the compositions of the isolates from both isolation procedures were similar, although solvent extraction gave higher yields. However, the precipitation method, which is easy to carry out and avoids the use of undesirable organic solvents, may be preferable in commercial processes for recovering these compounds. 相似文献
74.
The article shows results of an international and interdisciplinary project with the title ‘Rainfall and its Erosivity in Ethiopia’. The article contains information about the traditional soil conservation practices, the reasons for intervention with traditional soil conservation technologies, the historical background of instutionalized soil conservation activities, the institutional frame work for soil conservation activities and their achievements, and the different departments and organisations for soil and water conservation as far as soil erosion in Ethiopia is concerned. As a conclusion and recommendation, the major constraints of the past activities and the current situation including future trends were discussed. 相似文献
75.
76.
Alaa G. M. Osman Imam A. Mekkawy Johan Verreth Frank Kirschbaum 《Fish physiology and biochemistry》2007,33(1):1-13
Glucose-6-phosphate dehydrogenase (G6PDH), lactate dehydrogenase (LDH) and pyruvate kinase (PK) are key metabolic enzymes.
G6PDH has been used as a biomarker of pollution-induced carcinogenesis in fish. LDH has been used as marker of lesions in
toxicology and clinical chemistry, and PK catalyses the conversion of phosphoenol pyruvate to pyruvate, with regeneration
of ATP. The effect of different concentrations of lead nitrate on the activity of these enzymes in two different early ontogenetic
stages (embryonic and free embryonic stage) of the African catfish Clarias gariepinus was investigated. Embryo homogenates were used for measurements of G6PDH, LDH and PK activity spectrophotometrically at 340 nm
and 25°C. The ontogenetic variations of the three enzymes during early ontogeny, from the 30 h to the 168 h post-fertilisation
stage (PFS) (beginning of exogenous feeding), were studied. There was a significant decrease in activities of all three enzymes
from 30 h-PFS to 96 h-PFS, followed by a significant increase in G6PDH and LDH. PK showed insignificant fluctuations in activity.
Different patterns of enzyme activities were recorded due to exposure to different lead nitrate concentrations (100 μg/l,
300 μg/l and 500 μg/l). In the pre-hatching stage (30 h-PFS) the activity of the three enzymes increased at exposure to 100 μg/l
lead nitrate and then decreased with increasing dose. In the post-hatching stages (48 h-PFS–168 h-PFS) G6PDH activity increased
and LDH activity decreased with increasing lead concentrations. Unlike G6PDH and LDH, the PK enzyme fluctuated during the
post-hatching stages and did not reveal a specific trend of response (increase or decrease) with increasing lead concentrations.
Therefore, the measurement of G6PDH and LDH activities, but not PK activity, could be useful biomarkers of intoxication to
reveal the embryotoxic potential of lead nitrate in fish embryos. The post-hatching stages of the African catfish are more
sensitive than the pre-hatching stage (30 h-PFS) is, probably due to the protective capacity provided by the hardened chorion.
The interaction and the main effects of age and lead doses were found to be highly significant, referring to the great impact
of lead on these enzyme systems with increasing early development. 相似文献
77.
Erythrocytic lipid peroxidation has been implicated as a cause of anemia in Theileria annulata infection in cattle. The present study aimed to evaluate oxidative damage of membrane lipids and proteins in addition to hemoglobin (Hb) as three criterions of erythrocyte oxidation and their relation to erythrocyte deformability and anemia of newborn crossbred calves (Friesian × Egyptian Balady breed) naturally infected with T. annulata. Twenty-five T. annulata-infected calves (aged 20-30 days) along with 15 age matched healthy controls were used. Percentage of parasitemia varied from 12% to 63% (34.76 ± 3.05%). In comparison to controls, infected calves showed increased levels (P<0.001) of lipid peroxidation (malondialdehyde; MDA, 52%) and protein oxidation (protein carbonyls; PCs, 132%) in erythrocyte membrane as well as increased values of Hb oxidation (methemoglobin; MetHb, 186%), corpuscular osmotic fragility (15.1%) and hemolysis (free Hb; 195.5%). Parasitemia was positively correlated with MDA (r=0.41, P=0.039), PCs (r=0.45, P=0.023) and MetHb (r=0.40, P=0.042). Also, percent of erythrocytic deformability (echinocytosis) was positively correlated with MDA (r=0.49, P=0.013) and PCs (r=0.63, P<0.001). On the other hand, erythrocytic packed cell volume was negatively correlated with MDA (r=-0.44, P=0.028), PCs (r=-0.72, P<0.001) and MetHb (r=-0.42, P=0.037). In conclusion, T. annulata infection is associated with a parasitic burden-dependant oxidative damage to the erythrocyte membrane protein and lipid contents in addition to Hb. This oxidative damage is linked to the morphological changes of the erythrocyte and may act as mechanisms contribute to pathogenesis of anemia in T. annulata infection in newborn calves. 相似文献
78.
M T Musa O M Osman 《Revue d'élevage et de médecine vétérinaire des pays tropicaux》1990,43(4):505-510
An outbreak of suspected tick paralysis occurred in one-humped camels in Southern Darfur, the Sudan, between latitudes 11-12 degrees N and longitudes 24-25 degrees E, when the camels were herded in tick infested areas. It involved 251 camels of different ages, in ten herds causing 34.3% mortality. The symptoms were incoordination of movements, unsteady gait and recumbency followed by death or recovery. Hyalomma adults and/or Rhipicephalus nymphs and adults were incriminated to be the cause of the disease. Transient paralysis in a guinea pig was produced after experimental feeding of ticks. Removal of the camels from the tick infested areas and treatment against the ectoparasites with Lindane at the concentration of 0.23% contributed to controlling the disease. 相似文献
79.
Mohammad E. Hossain Sirajul Hoque Khan T. Osman 《Archives of Agronomy and Soil Science》2013,59(9):959-966
An experiment was conducted to observe the phosphate sorption potential of some soils of Bangladesh. Three soil series of calcareous origin, namely Sara (Aquic Eutrochrept), Gopalpur (Aquic Eutrochrept) and Ishurdi (Aeric Haplaquept), and two soil series of non-calcareous origin, namely Tejgaon (Rhodic Paleustult) and Ghatail (Aeric Haplaquept), were selected. The soils were equilibrated with dilute solution of calcium chloride containing graded concentrations of phosphate (0, 1, 2, 5, 10, 25 and 50?μg?P?mL?1), and the amount of phosphate sorbed or desorbed was determined. Although all the soils showed potential for sorbing phosphate from applied phosphorus, their ability to sorb phosphorus differed. Increasing rates of phosphate application increased the amount of P sorption but reduced phosphate sorption percentage in all soils except Tejgaon. Phosphate was sorbed by the soils in the order: Tejgaon > Ghatail > Ishurdi > Gopalpur > Sara at 50?μg?P?mL?1 application. Soils possessing higher amounts of free iron oxide and clay sorbed more phosphate from applied phosphorus. 相似文献
80.
Sitohy Mahmoud Taha Soad Abdel-Hamid Mahmoud Abdelbacki Ashraf Hamed Ali Osman Ali 《植物病害和植物保护杂志》2021,128(4):1101-1114
Journal of Plant Diseases and Protection - Methylated soy and chickpea proteins (MSP and MCP, respectively), and 11S globulin (a soy protein fraction), are characterized by net positive charges and... 相似文献