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71.
BACKGROUND/AIMS: We created a study group in order to investigate the effects of splenectomy and filgrastim. Filgrastim is an immunomodulator granulocyte colony-stimulating factor (G-CSF), that affects bacterial translocation. MATERIALS AND METHODS: We created 3 study groups with 30 male Sprague-Dawley rats; the first group included sham splenectomy, the second group was splenectomy, and the third group was splenectomy+ filgrastim group. RESULTS: The mean bacterial colony count of the cecum were 2.5 x 10(9) in group 1, 1.2 x 10(10) in group 2 and 3.5 x 10(9) in group 3. The differences between these groups were accepted as statistically significant. The mean counts of the terminal ileum were 1.1 x 10(9) in group 1, 5.5 x 10(10) in group 2 and 2.5 x 10(10) in group 3. The p values of group 1-2 were 0.036 (statistically significant) and 0.123 in groups 2-3) were not statistically significant. The mean counts of the liver were 0.2 x 10(4), 1 x 10(10) and 3.4 x 10(5), respectively. In comparison of the groups the p values of the first and last 2 groups were found to be 0.047 (statistically significant). The mean counts of the mesenteric lymph node were 0.7 x 10(3), 1 x 10(10) and 0.9 x 10(6) respectively. The p values were 0.343 for the first and the last 2 groups both. As they were above 0.05, they were not statistically significant. The degrees of liver Kupffer cell hyperplasia were (+) 40%, (+2) 50% and (+3) 10% (group 1), (+) 10%, (+2) 40% and (+3) 50% (group 2), (+2) 60% and (+3) 40% (group 3) (p = 0.0039). The rates of the absence of pathology in mesenteric lymph nodes were 70% (group 1), 90% (group 2) and 100% (group 3) (p = 0.049). These findings were statistically significant. CONCLUSIONS: We found that splenectomy has activated the whole predisposing factors of bacterial translocation and created the latter itself. In addition, we showed that filgrastim, a recently widespread used G-CSF, decreases bacterial translocation significantly. 相似文献
72.
Juan Carlos Hernandez-Castaneda Huseyin Kursad Sezer Lin Li 《The International Journal of Advanced Manufacturing Technology》2010,50(1-4):195-206
This paper presents a statistical analysis of the performance of an Ytterbium fibre laser utilising single and dual gas jets in a single pass to blind cut dry pine wood. Cutting wood with lasers is a multi-factor process and a proper combination of the parameters involved is needed to achieve high quality and optimum process efficiency. This study employs design of experiments and statistical modelling approach to investigate the significant process parameters along with their interactions. A high brightness, 1 kW IPG single mode Ytterbium-doped fibre laser was employed to produce blind cuts on samples of dry pine wood. The experiments were performed parallel to the direction of the wood fibre. The parameters investigated include laser power, focal plane position, traverse speed, gas pressure and single and dual gas jets. Results were compared using a number of process responses which define the efficiency of the cut in terms of kerf depth, mass removal and energy consumption as well as quality of the cut section considering the heat-affected zone, kerf width and roughness of the edge of the surface. It has been found that application of an additional gas jet produced a surface finish superior to the single jet. 相似文献
73.
In this study, the flow characteristic of the circular cylinder laid on the free surface is studied quantitatively using the particle image velocimetry technique. The flow phenomena in the upstream and downstream regions of the horizontal cylinder and free surface junctions increase the instability of the vortical flow structure significantly. Since the scour and burial process of the pipelines laid on the seabed depends mostly on the hydrodynamic behavior of the flow, the present investigation concentrates on the characterization of the flow structures using the time-averaged and instantaneous flow data. Distributions of velocity vectors, patterns of streamlines, vorticity contours and corresponding Reynolds stress correlations characterize the flow structure in detail. 相似文献
74.
Fundamental limits on time delay estimation in dispersed spectrum cognitive radio systems 总被引:1,自引:0,他引:1
Gezici Sinan Celebi Hasari Poor H. Vincent Arslan Huseyin 《Wireless Communications, IEEE Transactions on》2009,8(1):78-83
In this paper, fundamental limits on time delay estimation are studied for cognitive radio systems, which facilitate opportunistic use of spectral resources. First, a generic Cramer-Rao lower bound (CRLB) expression is obtained in the case of unknown channel coefficients and carrier-frequency offsets (CFOs) for cognitive radio systems with dispersed spectrum utilization. Then, various modulation schemes are considered, and the effects of unknown channel coefficients and CFOs on the accuracy of time delay estimation are quantified. Finally, numerical studies are performed in order to verify the theoretical analysis. 相似文献
75.
Sensitivity and specificity of infrared thermography in detection of subclinical mastitis in dairy cows 总被引:1,自引:0,他引:1
The objectives of this experiment were to determine interrelationships among mastitis indicators and evaluate the subclinical mastitis detection ability of infrared thermography (IRT) in comparison with the California Mastitis Test (CMT). Somatic cell count (SCC), CMT, and udder skin surface temperature (USST) data were compiled from 62 Brown Swiss dairy cows (days in milk = 117 ± 51, milk yield = 14.7 ± 5.2 kg; mean ± SD). The CORR, REG, and NLIN procedures of Statistical Analysis System (SAS Institute Inc., Cary, NC) were employed to attain interrelationships among mastitis indicators. The diagnostic merit of IRT as an indirect measure of subclinical mastitis was compared with CMT using the receiver operating characteristics curves. The udder skin surface temperature was positively correlated with the CMT score (r = 0.86) and SCC (r = 0.73). There was an exponential increase in SCC (SCC, ×103 cells/mL = 22.35 × e1.31 × CMT score; R2 = 0.98) and a linear increase in USST (USST, °C = 33.45 + 1.08 × CMT score; R2 = 0.75) as the CMT score increased. As SCC increased, USST increased logarithmically [USST, °C = 28.72 + 0.49 × ln(SCC, ×103 cells/mL); R2 = 0.72]. The USST for healthy quarters (SCC ≤400,000 cells/mL; n = 94) was different from that for subclinical mastitic quarters (SCC >400,000 cells/mL; n = 135) (mean ± SE; 33.45 ± 0.09 vs. 35.80 ± 0.08°C). The sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, positive predictive value, and negative predictive value were 95.6, 93.6, 14.97, 0.05, 95.0, and 93.6, respectively, for IRT and 88.9, 98.9, 83.56, 0.11, 99.2, and 86.1, respectively, for CMT. The area under the receiver operating characteristics curve for IRT and CMT was not different. In conclusion, as a noninvasive and quick tool, IRT can be employed for screening subclinical mastitis via measuring USST, with a high predictive diagnostic ability similar to CMT when microbiological culturing is unavailable. However, the reliability of IRT among cows with different characteristics and those living under various environmental conditions remains to be determined. 相似文献
76.
Cem Sensogut Murat Ozalp Huseyin Yesil 《International Journal of Adhesion and Adhesives》2009,29(5):589-592
In this study, the effects of borax pentahydrate addition to urea formaldehyde (UF) on the bonding characteristics and free formaldehyde content have been studied. Experiments related to the bending strength, withdrawal shear strength and free formaldehyde content have been conducted on the three-layered beech and poplar plywood which are prepared by the addition of borax pentahydrate into their adhesive mixtures in certain amounts. Addition of borax pentahydrate into the adhesive mixture did not statistically affect the bending strength and withdrawal shear strength of the plywood but did reduce the free formaldehyde content. 相似文献
77.
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79.
Ass. Prof. Dr. Gulsun ?zyurt Ali Serhat ?zk��t��k Abdurrahman Polat 《Journal für Verbraucherschutz und Lebensmittelsicherheit》2011,6(2):167-174
The effects of rosemary extract addition on oxidative stability of cooked sea bream during frozen storage period were investigated. Sea bream fillets were fried, oven baked and grilled. Three groups with rosemary extract were also cooked by the same methods and cooked samples (with and without rosemary extract) were stored in ?18?°C for 4?months. After cooking procedures, the FFA formation was quite similar in fresh-raw and fried sea bream fillets, but significantly increased oven baked (0.31?C0.33% oleic acid) and grilled fillets (0.39?C0.40% oleic acid). The highest value of PV was also obtained from grilled fillets (1.18?C1.58?meq/kg). However, TBA values (1.92?mg MA/kg for fresh-raw fillet) did not increase in sea bream fillets after the frying and grilling procedure except oven baking without rosemary extract (2.41?mg MA/kg). A considerable increase in the FFA, PV and TBA was observed in all cooked groups during frozen storage period. The treated samples with rosemary extract generally showed slower PV and TBA formation than those of the untreated samples. However, the additions of rosemary extract have positive effect on sensory quality of baked sea bream. 相似文献
80.