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141.
Meyerhoff RR Nighot PK Ali RA Blikslager AT Koci MD 《Comparative immunology, microbiology and infectious diseases》2012,35(1):63-69
The inducible nitric oxide synthase (iNOS) enzyme has long been recognized as a key mediator of innate immune responses to infectious diseases across the phyla. Its role in killing or inactivating bacterial, parasitic, and viral pathogens has been documented in numerous host systems. iNOS, and its innate immune mediator NO has also been described to have negative consequence on host tissues as well; therefore understanding the pathogenesis of any infectious agent which induces iNOS expression requires a better understanding of the role iNOS and NO play in that disease. Previous studies in our laboratory and others have demonstrated evidence for increased levels of iNOS and activity of its innate immune mediator NO in the intestine of turkeys infected with astrovirus. To begin to characterize the role iNOS plays in the innate immune response to astrovirus infection, we identified, characterized, developed tkiNOS specific reagents, and demonstrated that the intestinal epithelial cells induce expression of iNOS following astrovirus infection. These data are the first to our knowledge to describe the tkiNOS gene, and demonstrate that astrovirus infection induces intestinal epithelial cells to express iNOS, suggesting these cells play a key role in the antiviral response to enteric infections. 相似文献
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143.
Wasfi IA Al Ali WA Agha BA Kamel AM Al Biriki NA Al Neaimi KM 《Journal of veterinary pharmacology and therapeutics》2012,35(2):155-162
The pharmacokinetics and metabolism of meloxicam was studied in camels (Camelus dromedarus) (n = 6) following intravenous (i.v.) administration of a dose of 0.6 mg·kg/body weight. The results obtained (mean ± SD) were as follows: the terminal elimination half-life (t(1/2β) ) was 40.2 ± 16.8 h and total body clearance (Cl(T) ) was 1.94 ± 0.66 mL·kg/h. The volume of distribution at steady state (V(SS)) was 92.8 ± 13.7 mL/kg. One metabolite of meloxicam was tentatively identified as methylhydroxy meloxicam. Meloxicam and metabolite were excreted unconjugated in urine. Meloxicam could be detected in plasma 10 days following i.v. administration in camels using a sensitive liquid chromatography tandem mass spectrometry (LC/MS/MS) method. 相似文献
144.
Mehdi Zarifi Sébastien Buczinski Ali Rezakhani Mohammad Reza Mokhber Dezfouli Ali Khonsha 《Journal of Veterinary Cardiology》2012,14(3):415-421
ObjectivesTo study the effect of pregnancy and lactation on echocardiographic parameters in Holstein dairy cows.AnimalsNine multiparous high milk producing (HMP) dairy cows (producing more than 40 kg of milk per day in peak production) and 9 low milk producing (LMP) cows (producing less than 30 kg or milk per day in peak production).MethodsEchocardiography was performed twice; one month before calving and two months after calving.ResultsThe heart rate of HMP cows in the early lactation period was significantly higher than in the dry period. In LMP cows, there was a significant increase in left ventricular dimension in the early lactation period as compared to the dry period, and the interventricular septum in systole (IVSs) in the dry period was significantly thicker than early lactation period. In HMP cows, there was an increase in the right ventricular diameter in systole in the early lactation period as compared to the dry period. Left ventricular and aortic dimensions in the dry period of HMP were significantly higher than those of LMP cows. When the data were corrected for body weight, comparison of values of the dry period of HMP and LMP cows showed that left ventricular volume in systole in HMP was significantly higher and that IVSs, left ventricular fractional shortening and ejection fraction were significantly lower than in LMP cows.ConclusionsThis study demonstrated that lactation influences the intracardiac dimensions. The amount of milk production can influence echocardiographic parameters in dairy cows. 相似文献
145.
Abid Ali Farooq Ahmad Antonio Biondi Yusha Wang Nicolas Desneux 《Journal of pest science》2012,85(3):359-366
Various plants are well known for their insecticidal activity and their use was maintained for millennia throughout all the agricultural regions of the world. In a current context, the use of Botanical insecticides represents one of the best alternatives to chemicals for the development of environmental-friendly strategies for stored grain pest control. Datura alba Nees is a plant found extensively in the warmer regions of the world and it is used as a medicinal plant. This study aims to assess the contact toxicity and the trans-generational effect of D.?alba leaf extract (DLE) against two important insect pests on stored rice, Trogoderma granarium and Sitophilus oryzae, under laboratory conditions. Filter papers were soaked in three DLE concentration solutions and in two control treatments: water and acetone. The survivor specimens (F0) were transferred to a new untreated feeding substrate and the population build up of the two following generations (F1 and F2) were counted after 30 and 60?days, respectively. The highest DLE concentration (2.5?%) induced the significantly highest mortality with 33.5 and 45?% mortality in T.?granarium and S.?oryzae after 7?days of exposure, respectively. The DLE long-term effect toward both tested species was also proved by the high demographic decrease in the F2 generations, when compared to control groups. This study is the first step toward establishing a scientific basis for the effective application of D.?alba plant materials as biorational tools to control stored grain pests. 相似文献
146.
Nikbakht G Rezaii H Stear MJ Talebi MA Mahmoudzadeh H 《Veterinary journal (London, England : 1997)》2012,192(3):547-549
Ovar-DRB1 is one of the most important response genes in the major histocompatibility complex (MHC) class II region of sheep. Gene polymorphism in the second exon of Ovar-DRB1 in three different Iranian fat-tailed sheep breeds (Lori-Bakhtiari, Shaul and Zandi) was analyzed by either restriction fragment length polymorphisms (RFLP) or direct sequencing. A total of 92 Lori-Bakhtiari, 40 Shaul, and 47 Zandi sheep were examined. PCR-RFLP identified 17 genotypes in Lori-Bakhtiari sheep, 12 in Shaul sheep and 11 in Zandi sheep. Collectively, 24 different genotypes could be found for Iranian fat-tailed sheep. Using direct sequencing, seven new sequences in exon 2 of the Ovar-DRB1 gene were identified. Generalized linear modeling with a multinomial error structure showed that the sheep populations had significantly different allele frequencies. 相似文献
147.
Takuro Hirai Kei Sawata Ali Awaludin Yoshihisa Sasaki Takeyoshi Uematsu 《Journal of Wood Science》2012,58(2):128-134
Shaking table tests of the wall-floor joints of wooden light-frame constructions under forced harmonic vibrations are conducted
in this study so as to observe the dynamic responsive characteristics. The principal results are as follows: The responsive
characteristics of timber constructions under strong earthquakes cannot be directly correlated with their resonant frequencies
under free or forced vibrations with low input accelerations, because they behave as continuous bodies when the input accelerations
are less than the apparent frictional limits of structural joints. The apparent frictional limits are reduced by periodic
fluctuation of the effective vertical loads as a result of the vertical motion of the specimens. The characteristic dynamic
responses of wall-floor joints depend clearly upon the frequency and input accelerations of forced vibrations. These dependencies
arise from the nonlinear load-slip relationship of the wall-floor joints. The equivalent stiffness in their successive transient
phases decreases as joint slip increases, which gradually changes the resonant frequencies of the wall-floor joints. This
indicates that the frequency components dominant to ultimate or safety-limit resistance should be distinguished from those
dominant to allowable or serviceability-limit resistance. 相似文献
148.
Bahador Bagheri Bahram Sohrabi Ali Akbar Movassaghpour Simin Mashayekhi Afagh Garjani Mehriar Shokri Masoud Pezeshkian Alireza Garjani 《Iranian Biomedical Journal》2014,18(2):76-81
Bacground: Evidence from several lines of investigations suggests that Toll-like receptor 4 (TLR4) is involved in atherosclerosis as a bridge between innate and acquired immunity. Percutaneous coronary intervention (PCI) can trigger inflammation through activation of human TLR4 (hTLR4) on monocytes. Hydrocortisone as an anti-inflammatory and immuno-suppressant agent has multiple mechanisms of action. In this study, we aimed at assessing the effects of hydrocortisone on monocyte expression and activity of hTLR4 in patients underwent PCI. Methods: Blood samples were taken from a total of 71 patients with chronic stable angina who were scheduled for a PCI, before the intervention. Thirty patients received 100 mg hydrocortisone prior to the procedure. Control group was composed of 41 patients underwent PCI without receiving hydrocortisone. Blood collection was repeated 2 and 4 h after PCI. The expression of hTLR4 on the surface of CD14+ monocytes and the serum levels of TNF-α and IL-1β were measured using flowcytometry and Sandwich ELISA. Results: Compared with controls, hydrocortisone significantly reduced monocyte expression of hTLR4 in test group (P<0.01). In addition, it had a significant effect on reduction of serum concentrations of TNF-α and IL-1β in test group in a time-dependent manner (P<0.01). Conclusion: In this study, hydrocortisone was able to reduce the hTLR4/CD14 positive monocytes and its related pro-inflammatory cytokines, thus it can decrease inflammatory responses following PCI. Key Words: Toll-like receptor 4, Cytokines, Hydrocortisone 相似文献
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150.
Studying the impregnation and distribution of oil-based preservative in dried wood is complicated as wood is a nonhomogeneous, hygroscopic and porous material, and especially of anisotropic nature. However, this study is important since it has influence on the durability of wood. To enhance the durability of thermally modified wood, a new method for preservative impregnation is introduced, avoiding the need for external pressure or vacuum. This article presents a study on preservative distribution in thermally treated Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) sapwood using computed tomography scanning, light microscopy, and scanning electron microscopy. Secondary treatment of thermally modified wood was performed on a laboratory scale by impregnation with two types of preservatives, viz. Elit Träskydd (Beckers) and pine tar (tar), to evaluate their distribution in the wood cells. Preservative solutions were impregnated in the wood using a simple and effective method. Samples were preheated to 170 °C in a drying oven and immediately submerged in preservative solutions for simultaneous impregnation and cooling. Tar penetration was found higher than Beckers, and their distribution decreased with increasing sample length. Owing to some anatomical properties, uptake of preservatives was low in spruce. Besides, dry-induced interstitial spaces, which are proven important flow paths for seasoned wood, were not observed in this species. 相似文献