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141.
Camels are the prime source of meat and milk in many desert regions of the world including Saudi Arabia. Paratuberculosis of camels, locally called Silag, is a serious and invariably fatal disease in the Arabian camel. Six camels were used in this study. Five camels with clinical paratuberculosis were used to study the pathology of the disease and confirm its aetiology. The sixth camel was clinically healthy and used as a control. The camels were examined clinically and bled for haematological and blood chemistry analysis. They were then humanely killed with a high intravenous dose of thiopental sodium (10 mg/kg) for pathological studies as well as obtaining tissues for microbiological and molecular studies. The clinical signs of the disease were emaciation, diarrhoea, alopecia, wry neck and pale mucous membranes. Laboratory diagnosis showed reduced haemoglobin concentration, low haematocrit and high activity of the serum enzyme alanine aminotransferase. Serum creatinine concentration was normal. These results indicated the infected camels were anaemic and the function of their livers was affected. Postmortem examination showed thickened and corrugated intestinal mucosa, enlarged granulomatous mesenteric lymph nodes, miliary and diffuse granulomas in the liver (in four camels), generalized lymph node granulomas (in one camel), splenic granuloma (in one camel) and mediastinal lymph node granuloma (in two camels). Histopathological examination showed diffuse infiltration of macrophages in all organs showing lesions. Ziehl–Neelsen staining of tissue scraping and tissue sections showed masses of acid fast bacilli, except for the spleen. Infection with Mycobacterium avium subsp. paratuberculosis was confirmed by PCR by targeting the IS900 gene.  相似文献   
142.
Thiacloprid (TCP) is a widely used neonicotinoid insecticide with a probable toxic hazard to animals and human beings. This hazard has intensified the demand for natural compounds to alleviate the expected toxic insults. This study aimed at determining whether astaxanthin (ASX) could mitigate the hepatotoxic effect of TCP and diminish its suppressive effect on immune responses in rats. Animals received TCP by gavage at 62.1 mg/kg (1/10th LD50) with or without ASX at 40 mg/kg for 60 days. Intoxicated rats showed modulation of serum transaminases and protein profiles. The hemagglutination antibody titer to sheep red blood cells (SRBC) and the number of plaque-forming cells in the spleen were reduced. The cell-mediated immunity and phagocytosis were suppressed, while serum interleukins IL-1β, IL-6, and IL-10 were elevated. Additionally, malondialdehyde, nitric oxide, and 8-hydroxy-2′-deoxyguanosine levels were increased in the liver, spleen, and thymus, with depletion of glutathione and suppression of superoxide dismutase and catalase activities. The expressions of inducible nitric oxide synthase and the high mobility group box protein 1 genes were upregulated with histomorphological alterations in the aforementioned organs. Cotreatment with ASX markedly ameliorated the toxic effects of TCP, and all markers showed a regression trend towards control values. Collectively, our data suggest that the protective effects of ASX on the liver and immune system of TCP-treated animals depend upon improving the antioxidant status and relieving the inflammatory response, and thus it may be used as a promising therapeutic agent to provide superior hepato- and immunoprotection.  相似文献   
143.
Since 1960, the steppe regions of North Africa have been subject to an increasing desertification, including the degradation of traditional pastures. The initially dominant species(Artemisia herba-alba, Lygeum spartum and Stipa tenacissima) declined and were progressively replaced by other species(Atractylis serratuloides and Salsola vermiculata) that are more tolerant to the new conditions. It is not clear whether these changes are due to anthropogenic reasons or climatic determinism. We have carried out a statistical analysis of the climate to detect putative rainfall changes during the 20~(th) century in the Algerian steppes based on data from 9 meteorological stations, including 2 Saharan stations(El Oued and Touggourt), 3 pre-Saharan stations(Biskra, Laghouat and Ain Sefra) and 4 steppe stations(Djelfa, Saida, Méchéria and El-Bayadh) located in the arid high plains, which represent the bioclimate diversities of the region. Previous studies suggested that significant rainfall changes for the 20~(th) century only had records in the south of the Oran region. Most of the studies, however, looked at restricted territories over limited periods, and did not integrate the rainiest period 2004–2014. Our work is designed to integrate all the longest time series of meteorological data available for the steppe regions of Algeria. Our results confirm the spatial rainfall distribution(significant rainfall changes only recorded in the southwestern region) evidenced by previous studies, and reveal a decreasing rainfall gradient from northeastern to southwestern Algeria. Moreover, the results reveal a trend of significant decrease of rainfall in the southern Oran region, marked by two drought periods in 1980–1985 and 1999–2003. However, with the exception of the southwestern region, rainfall overall has not declined since the beginning of the 20~(th) century. While less marked in other regions, the drought appear to have affected all territories of the Algerian steppe. Consequently, our study implies that the climate was not a leading influence in the on-going degradation of the vegetation cover of steppe landscapes. Such a vegetation evolution thus appears to be have been determined more by human activities than by climate forcing.  相似文献   
144.
Journal of Plant Diseases and Protection - A study was carried out for identification and detection of Phytophthora spp. from soil and plant samples, collected from Solanaceous crops in Egypt and...  相似文献   
145.
146.
Children with Specific Language Impairment (SLI) may have some kind of memory disorder that could increase their linguistic impairment. This study assessed the short-term memory skills in Arabic speaking children with either Expressive Language Impairment (ELI) or Receptive/Expressive Language Impairment (R/ELI) in comparison to controls in order to estimate the nature and extent of any specific deficits in these children that could explain the different prognostic results of language intervention. Eighteen children were included in each group. Receptive, expressive and total language quotients were calculated using the Arabic language test. Assessment of auditory and visual short-term memory was done using the Arabic version of the Illinois Test of Psycholinguistic Abilities. Both groups of SLI performed significantly lower linguistic abilities and poorer auditory and visual short-term memory in comparison to normal children. The R/ELI group presented an inferior performance than the ELI group in all measured parameters. Strong association was found between most tasks of auditory and visual short-term memory and linguistic abilities. The results of this study highlighted a specific degree of deficit of auditory and visual short-term memories in both groups of SLI. These deficits were more prominent in R/ELI group. Moreover, the strong association between the different auditory and visual short-term memories and language abilities in children with SLI must be taken into account when planning an intervention program for these children.  相似文献   
147.
148.
This study was designed to evaluate effects of different combinations of cryoprotectants on the ability of vitrified immature buffalo oocytes to undergo in vitro maturation. Straw and open‐pulled straw (OPS) methods for vitrification of oocytes at the germinal vesicle stage also were compared. The immature oocytes were harvested from ovaries of slaughtered animals and were divided into three groups: (i) untreated (control); (ii) exposed to cryoprotectant agents (CPAs); or (iii) cryopreserved by straw and OPS vitrification methods. The vitrification solution (VS) consisted of 6 m ethylene glycol (EG) as the standard, control vitrification treatment, and this was compared with 3 m EG + 3 m dimethyl sulfoxide (DMSO), 3 m EG + 3 m glycerol, and 3 m DMSO + 3 m glycerol. Cryoprotectants were added in two steps, with the first step concentration half that of the second (and final) step concentration. After warming, oocyte samples were matured by standard methods and then fixed and stained for nuclear evaluation. Rates of MII oocytes exposed to CPAs without vitrification were lower (54.3 ± 1.9% in EG, 47.5 ± 3.4% in EG + DMSO, 36.8 ± 1.2% in EG + glycerol and 29.9 ± 1.0% in DMSO + glycerol; p < 0.05) than for the control group (79.8 ± 1.3%). For all treatments in each vitrification experiment, results were nearly identical for straws and OPS, so all results presented are the average of these two containers. The percentages of oocytes reaching telophase‐I or metaphase‐II stages were lower in oocytes cryopreserved using all treatments when compared with control. However, among the vitrified oocytes, the highest maturation rate was seen in oocytes vitrified in EG + DMSO (41.5 ± 0.6%). Oocytes cryopreserved in all groups with glycerol had an overall low maturation rate 19.0 ± 0.6% for EG + glycerol and 17.0 ± 1.1% for DMSO + glycerol. We conclude that the function of oocytes was severely affected by both vitrification and exposure to cryoprotectants without vitrification; the best combination of cryoprotectants was EG + DMSO for vitrification of immature buffalo oocytes using either straw or OPS methods.  相似文献   
149.
This paper presents the results from a survey that was carried out to determine the host plants of tomato leaf miner, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) in five States in Sudan. This survey was carried out in greenhouses and open‐field vegetable production areas between the years 2011 and 2014 using pheromone traps. The survey showed that the main host plant of T. absoluta is tomato (Lycopersicon esculentum), but it also attacks potato (Solanum tuberosum), eggplant (S. melongena) Jimson weed (Datura stramonium) and S. dubium in the family Solanaceae, and broad bean (Vicia faba) and alfalfa plant (Medicago sativa) in the family Fabaceae. This paper is the first record of the following plans being hosts for T. absoluta: Watermelon (Citrullus lanatus) in the family Cucurbitaceae, Physic nut (Jatropha curcas) in the family Euphorbiaceae, spiny amaranth (Amaranthus spinosus) in the family Amaranthaceae, Ramtouk (Xanthium brasilicum) in the family Asteraceae and S. dubium. The study showed that the leafminer male numbers and the symptoms were significantly increased in S. melongena and S. dubium after severe damage and complete loss of the main host, the tomato crop and these two species may be the preferred alternative host plants.  相似文献   
150.
The thermal treatment method was employed to achieve higher homogeneity of calcium ferrite (CaFe2O4) and Poly (vinyl alcohol) (PVA) nanocomposites. The influences of phase transformation on physical and biological properties of calcined specimens were investigated by various experimental techniques including X-ray diffraction (XRD), Transmission Electron Microscopy (TEM), high resolution Field emission scanning electron microscope (FESEM) and Fourier transform infrared spectroscopy (FT-IR). Heat treatment was conducted at temperatures between 723 and 923 K, so that a phase transformation occurred from cubic to orthorhombic spinel structure at 923 K. The chemical analysis of the PVA/CaFe2O4 nanocomposite was performed by energy dispersion X-ray analysis (EDXA), demonstrated the PVA/CaFe2O4 nanocomposites contained the elements of C, Ca, Fe, and O. The formed nanocomposites exhibited ferromagnetic behaviors which were confirmed by using a vibrating sample magnetometer (VSM). The calcined specimens were carried out to an antimicrobial or antifungal test.  相似文献   
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