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21.

Successful preventive and control measures of zoonotic diseases require updated epidemiological data. Sylvatic rabies is endemic in Oman since 1990. Studying of the prevalence of animal rabies in Oman (2017–2019) was the goal of the current study besides the clinical–histopathological investigations of rabies in different animal species. A total of 117 whole brains of different animal species from different regions of Oman were examined by fluorescent antibody test (FAT) and histopathology for rabies during 2017–2019. Sixty-four samples (54.7%) were positive for rabies by FAT. The most affected species were goat (53.1%) followed by camel (18.8%), which pose a great risk to farmers and veterinarians. Positive fox cases were (10.9%). Most confirmed cases of animal rabies were submitted from Northern regions of Oman. Rabies was reported recently in Al Wusta among wild ruminants, Central Oman. The seasonal cycle of animal rabies in Oman was year-round with the peak from December to April. The clinical signs and neuropathological findings were nearly similar in different animal species. Histopathology-positive cases had Negri bodies in pyramidal and purkinje neurons, non-suppurative encephalitis features, and neuronal degeneration and necrosis. The sensitivity and specificity of histopathological diagnosis of rabies in different animals were 76.47% and 100.00%, respectively. Finally, sylvatic rabies remains a major challenge to the public and animal health in Oman. Although of the value of histopathological diagnosis of rabies if no other technique is available, other complementary tests must be employed to confirm negative results.

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22.
In recent years, flexible, mechanically strong and environmental friendly thermal insulation materials have attracted considerable attention. In this work, silica aerogel/polyethylene terephthalate (PET) nonwoven fiber composite with desirable characteristics was prepared via a two-step sol-gel process followed by an ambient drying method through immersing the PET nonwoven fiber into silica sol. The silica aerogel particles were characterized by FTIR, FE-SEM, TGA and nitrogen adsorption analysis. The morphology and hydrophobic properties of neat PET nonwoven fiber and its silica aerogel composite were also investigated. For studying thermal protective properties, the thermal diffusivity was calculated from temperature distribution curves. The mean pore size of 11 nm, the surface area of 606 m2/g and the total pore volume of 1.77 cm3/g for the silica aerogel particles in the composite are obtained from nitrogen adsorption analysis, indicating the aerogel can maintain its high porosity in the nonwoven composite structure. Silica aerogel particles were efficiently covered the surface of the PET fibers and completely filled the micron size pores of the nonwoven fiber leading to a stronger hydrophobicity and higher thermal insulation performance in the aerogel composite samples compared to the neat PET nonwoven. In this regard, an almost 64 % decrease in the thermal diffusivity was achieved with 66 wt% silica aerogel.  相似文献   
23.
Preeclampsia is a disease regarding with altered vascular reactivity leading to hypertension of the mother and metabolic alterations in the fetus. This study aimed to assess nitric oxide and bleeding time following administration of magnesium sulfate to preeclamtic patients compared to normotensive pregnant women. A total of 112 subjects (56 preeclamtic patients and 56 normotensive pregnant controls) were enrolled in this case-control study. Cases and controls were matched for age, BMI, gestational age, parity and gravidity. Total concentration of nitrite and nitrate (NOx) was measured before and during magnesium sulfate (MgSO4) treatment using a modified Griess-based method. RESULTS: Systolic and diastolic blood pressures were significantly decreased during MgSO4 treatment in preeclamtic patients (p < 0.0001). NOx levels were significantly increased in preeclamtic women after MgSO4 administration (33.7 +/- 18.5 vs. 50.2 +/- 21.6, p < 0.0001) but it was not seen in normotensive parturients (52.4 +/- 28.9 vs. 57.3 +/- 21.7, p = 0.362). The bleeding time was scarcely increased following magnesium sulfate treatment in preeclamptic patients compared to normotensive pregnant women but it was not significant (p = 0.18). In addition, there was only a significantly reverse correlation between NOx levels and systolic or diastolic blood pressure in preeclamtic parturients after MgSO4 treatment (r = -0384; p = 0.003 and r = -0.29; p = 0.03, respectively). This study demonstrates that administrating MgSO4 to preeclamtic patients induced significant changes in NOx production which had a major role in modulating vasculature changes in preeclamsia.  相似文献   
24.
Journal of Crop Science and Biotechnology - The analysis of genetic diversity in medicinal plant species can greatly facilitate germplasm conservation and selection for use in breeding schemes. The...  相似文献   
25.
Genetic Resources and Crop Evolution - Hymenocrater comprises of 11 species throught the world. The genus is an Irano-Turanian elements, which has several usages in traditional medicine. Northeast...  相似文献   
26.
Background: Diabetes is a major public health problem. The development of new therapies that are able to improve glycemia management and even to cure diabetes is of great interest. In this study, protective effects of sodium tungstate against STZ-induced beta-cell damages were investigated. Methods: Sixty rats were divided into six groups: control, diabetic, sodium tungstate treated diabetic rats from one week before STZ injection (TDB), food-restricted diabetic (FRD), tungstate treated control, sodium tungstate treated diabetic rats from one week after STZ administration (TDA). We evaluated serum insulin, glucose and glucose tolerance; liver glycogen content, glucokinase (GK) activity; blood and pancreas antioxidant power, lipid peroxidation; and fuchsin-aldehyde histochemical staining of beta-cells. Results: Blood glucose levels of TDB group were lower than other diabetic groups (P<0.01). Blood insulin levels of all diabetic groups were lower than controls (P<0.01). Glucose intolerance improved in TDB animals. Blood and pancreas antioxidant power, liver glycogen contents and GK activities and granulated beta cells increased in TDB rats in comparison with other diabetic groups (P<0.01). Likewise, lipid peroxidation decreased significantly in TDB rats (P<0.01). Conclusions: Results suggested that sodium tungstate if administrated before STZ injection improves glycemic state by a direct effect on pancreatic beta-cells and preserves them by reducing the activity of these cells at the time of STZ injection, reducing STZ-induced oxidative stress, reducing insulin secretion, or all of the above mentioned.  相似文献   
27.
Journal of Soils and Sediments - Carbon capture and storage (CCS) has been frequently discussed as a strategy for meeting CO2 emission reduction and its targets. However, some critical issues have...  相似文献   
28.
Recently, the nanotechnology industry has seen a growing interest in integrating silver nanoparticles(AgNPs) into agricultural products, which increases soil exposure to these particles. This demands an investigation into the effect of AgNPs on soil health. Changes in soil enzyme activities upon exposure to AgNPs can serve as early indicators of any adverse effects that these particles may have on soil quality. This study aimed to determine the effects of AgNP size, concentration, coating, and e...  相似文献   
29.
The addition of zeolites to soil modifies soil physical and chemical properties. The objectives of this research were to study the effect of zeolite on saturated hydraulic conductivity, K s, and crack behavior in a silty clay paddled soil. Soil samples were mixed with 0, 4, 8 and 12 g kg?1 of zeolite for K s determination, and 0, 2, 4, 8 and 12 g kg?1 for soil crack measurements. Saturated hydraulic conductivity was measured using the constant head method. The results indicated that K s was significantly increased at a zeolite application rate of 8 g kg?1. Furthermore, an increase in zeolite content up to 8 g kg?1 decreased soil crack area after paddling and first rewetting. Higher amounts of zeolite (e.g. 12 g kg?1) increased crack density after the second rewetting. However, a 50% reduction in crack depth occurred with zeolite application rates of 8 and 12 g kg?1 in comparison with controls. Thus, a zeolite application rate of 8 g kg?1 is recommended for soil crack reduction in intermittent-flood irrigation. Furthermore, a relationship was obtained between crack area density (Ln), gravimetric soil water content and zeolite application rate. After the second irrigation, a relationship was also obtained between crack depth, gravimetric soil water content and zeolite application rate. Crack depth showed a positive and highly significant linear correlation with crack width.  相似文献   
30.
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