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Susann Piesnack Mairi E Frame Gerhard Oechtering Eberhard Ludewig 《Veterinary radiology & ultrasound》2013,54(6):618-622
The ability to read patient identification microchips relies on the use of radiofrequency pulses. Since radiofrequency pulses also form an integral part of the magnetic resonance imaging (MRI) process, the possibility of loss of microchip function during MRI scanning is of concern. Previous clinical trials have shown microchip function to be unaffected by MR imaging using a field strength of 1 Tesla and 1.5. As veterinary MRI scanners range widely in field strength, this study was devised to determine whether exposure to lower or higher field strengths than 1 Tesla would affect the function of different types of microchip. In a phantom study, a total of 300 International Standards Organisation (ISO)‐approved microchips (100 each of three different types: ISO FDX‐B 1.4 × 9 mm, ISO FDX‐B 2.12 × 12 mm, ISO HDX 3.8 × 23 mm) were tested in a low field (0.5) and a high field scanner (3.0 Tesla). A total of 50 microchips of each type were tested in each scanner. The phantom was composed of a fluid‐filled freezer pack onto which a plastic pillow and a cardboard strip with affixed microchips were positioned. Following an MRI scan protocol simulating a head study, all of the microchips were accurately readable. Neither 0.5 nor 3 Tesla imaging affected microchip function in this study. 相似文献
924.
This study was conducted to investigate the effects of Bacillus subtilis B10 spores on the viability and biological functions of murine macrophage. RAW 264.7 cells were stimulated both with and without B. subtilis B10 spores for 12 h. Then cell viability was determined to evaluate the cytotoxic effect of B. subtilis B10 spores to the cells, and the activities of acid phosphatase (ACP) and lactate dehydrogenase (LDH), the production of nitric oxide (NO) and inducible nitric oxide synthase (iNOS), and the secretion of inflammatory cytokines were measured to analyze the functions of macrophages. The results showed that B. subtilis B10 spores were not harmful to RAW 264.7 cells and they also strongly enhanced the activities of ACP and LDH (P < 0.01), remarkably increased NO and iNOS production (P < 0.01), and significantly stimulated the secretion of pro‐inflammatory cytokines, including tumor necrosis factor‐alpha (TNF‐α), interferon‐gamma (IFN‐γ), interleukin‐1 beta (IL‐1β), IL‐6, IL‐8 and IL‐12 (P < 0.01) while they reduced anti‐inflammatory cytokine IL‐10 (P < 0.01). The outcomes suggest that B. subtilis B10 spores are not only safe for murine macrophages, but also can activate these cells and enhance their immune function. The above findings suggest that B. subtilis B10 spores are potentially probiotic. 相似文献
925.
选用20头胎次相近和分娩期相近的中国荷斯坦奶牛,随机分为4组,对照组为基础日粮,3个处理组在基础日粮中分别添加3.0、6.0和9.0g/a的酵母铬。试验期为2周,从分娩当天持续到产后14d。结果表明,(1)与对照组相比,添加酵母铬可以提高血清中总抗氧化能力(T—AOC),超氧化物歧化酶(SOD)和谷胱苷肽过氧化物酶(GSHPx)的活力(P〈0.01),降低丙二醛的浓度;(2)酵母铬降低了皮质醇含量,提高了胰岛素活性。本试验条件下,发现基础日粮添加9.0g/d的酵母铬,使铬添加水平为0.8mgCr/kg时,效果较好。为研究在日粮中添加不同水平的酵母铬对围产后期奶牛抗氧化性能的影响提供依据。 相似文献
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927.
给小鼠灌服不同剂量(每kg体重灌服9、5、7 g生药)的党参多糖口服液后,通过测定小鼠免疫脏器指数、网状内皮系统吞噬功能、半数溶血值等指标的变化评价其对免疫系统的作用。结果显示,党参多糖口服液可显著增强小鼠网状内皮系统的吞噬功能,提高成年小鼠脾脏指数(P<0.05),能显著增强小鼠半数溶血值,提高小鼠的血清溶血素抗体生成水平(P<0.05),说明党参多糖口服液有显著的免疫调节能力。该试验可为党参多糖口服液的临床应用提供参考。 相似文献
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929.
AD Mackay 《New Zealand veterinary journal》2013,61(6):281-288
Abstract AIM: To find evidence for localisation in the uterus, and fetal infection, of Leptospira spp. in farmed deer in the lower North Island of New Zealand during and shortly after the breeding season. METHODS: Between February and July 2008, 116 blood samples, 120 kidneys, 120 uteri and 27 fetuses were collected from 120 mixed-age hinds from lines from nine farms, at a deer slaughter premises. Serum samples were tested for antibodies against Leptospira borgpetersenii serovar Hardjo-bovis and Leptospira interrogans serovar Pomona, using the microscopic agglutination test (MAT). For both serovars, a titre of >1:48 was considered positive. Samples from kidneys, uteri and fetal tissue were subjected to bacterial culture, using Ellinghausen-McCullough-Johnson-Harris (EMJH) medium, and real-time PCR, using DNA gyrase subunit B gene primers. RESULTS: Thirty-four of 116 (29.3%) serum samples were positive for serovar Hardjo-bovis, and 13 (11.2%) for serovar Pomona. Seven of 120 kidneys were positive for serovar Hardjo-bovis by culture, and five of these, but no others, were positive by real-time PCR. Of 120 uteri, none was culture- or PCR-positive. None of 27 fetal samples was culture-positive but one was positive by real-time PCR. The dam of the PCR-positive fetus was culture-negative from the kidney, but had an MAT titre of 1:192 for Hardjo-bovis. CONCLUSIONS: Attempts to isolate Leptospira spp. from the genital tracts and early fetuses of farmed deer were unsuccessful. However, molecular evidence suggested fetal infection in one case. This finding justifies further study of the role of leptospires in the genital tract and fetus and its association with reproductive loss in farmed deer. 相似文献
930.
Reasons for performing study: The use of two‐dimensional speckle tracking (2DST) for quantification of left ventricular (LV) function has recently been described in horses using long‐axis images and short‐axis images at chordal but not at papillary muscle level. Objectives: To compare the feasibility and reliability of 2DST for quantification of circumferential and radial LV function in short‐axis images at papillary muscle and chordal level. Methods: Repeated echocardiographic examinations were performed on 10 healthy trotter horses by 2 observers from a right parasternal short‐axis view at papillary muscle and chordal level. Segmental and averaged peak values and timing of circumferential and radial strain and strain rate, radial displacement and rotation were measured in 6 LV wall segments in each imaging plane. Global peak values were calculated for circumferential strain and strain rate. The inter‐ and intraobserver within‐ and between‐day variability was assessed by calculating coefficients of variation for repeated measurements. Results: 2DST analysis was feasible in each cardiac cycle, although tracking was often inadequate during early diastole. Measurements of averaged systolic circumferential and radial strain and strain rate and radial displacement as well as global circumferential strain and strain rate could be determined with low variability. Early and late diastolic strain rate and systolic rotation showed a moderate variability. Radial segmental measurements were more reliable than circumferential measurements. The interventricular septum showed a higher circumferential and lower radial strain compared with the LV free wall. Peak timing was earlier at papillary muscle compared with chordal level. Conclusions: 2DST measurements of global and regional circumferential and radial LV wall motion are feasible both at papillary muscle and chordal level. Potential relevance: Several measurements had good reliability and should be used for evaluation of the technique in a clinical setting. 相似文献