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141.
142.
Hege  Kippenes  DVM  Patrick R.  Gavin  DVM  PhD  Ronald D.  Sande  DVM  MS  PhD  Dennis  Rogers  RT  Vaughn  Sweet  MS 《Veterinary radiology & ultrasound》2000,41(4):371-376
The purpose of this retrospective study was to evaluate the repositioning accuracy of different positioning devices in order to determine their applicability for potential use in conformal radiation therapy for animals. Forty-four animals with spontaneous tumors of the head were included. The animals were divided into 3 groups determined according to the positioning device used. Group 1 animals were positioned using a thermoplastic mask. Group 2 animals were positioned using a head holder. Group 3 animals were positioned using the head holder and an inflatable pillow. The time of presentation determined which position device was used. Port films of the 44 patients were reviewed retrospectively, and the repositioning precision was recorded by measurements in three orthogonal planes. Groups 2 and 3 had significantly better repositioning accuracy (P < or = 0.05) compared to Group 1. The position variation was not significantly different (P < or = 0.05) between Groups 2 and 3 in the lateral and longitudinal direction. Group 3 had a median reposition variation of 0.5 to 1.0 mm, with a standard deviation of 1.0 to 1.5 mm.  相似文献   
143.
Susan M.  Newell  DVM  MS  John P.  Graham  MVB  MSc  Gregory D.  Roberts  DVM  MS  Pamela E.  Ginn  DVM  Cleatis L.  Chewning  RT    Jay M.  Harrison  MS  Camille  Andrzejewski  BS 《Veterinary radiology & ultrasound》2000,41(1):27-34
Magnetic resonance images of the cranial abdomen were acquired from 15 clinically normal cats. All cats had T1-weighted images, 8 cats had T2-images made and 7 cats had T1-weighted post Gd-DTPA images acquired. Signal intensity measurements for T1, T2, and T1 post contrast sequences were calculated for liver, spleen, gallbladder, renal cortex, renal medulla, pancreas, epaxial muscles, and peritoneal fat. On T1-weighted images the epaxial muscle had the lowest signal intensity, followed by renal medulla, spleen, renal cortex, pancreas, liver and fat, respectively. On T2-weighted images, epaxial muscle had the lowest signal intensity followed by liver, spleen, fat, and gallbladder lumen. Calculations of specific organ percent enhancement following contrast medium administration were made and compared with that reported in humans. A brief review of the potential clinical uses of MR in cats is presented.  相似文献   
144.
Scaffold proteins: hubs for controlling the flow of cellular information   总被引:2,自引:0,他引:2  
The spatial and temporal organization of molecules within a cell is critical for coordinating the many distinct activities carried out by the cell. In an increasing number of biological signaling processes, scaffold proteins have been found to play a central role in physically assembling the relevant molecular components. Although most scaffolds use a simple tethering mechanism to increase the efficiency of interaction between individual partner molecules, these proteins can also exert complex allosteric control over their partners and are themselves the target of regulation. Scaffold proteins offer a simple, flexible strategy for regulating selectivity in pathways, shaping output behaviors, and achieving new responses from preexisting signaling components. As a result, scaffold proteins have been exploited by evolution, pathogens, and cellular engineers to reshape cellular behavior.  相似文献   
145.
146.
A study was conducted to optimise a multiplex serological immunoassay for use in identification of goats infected with Mycobacterium bovis. To assess assay specificity, 31 goats with a history of being free from M. bovis infection were used. To determine assay sensitivity, 180 Single Intradermal Comparative Tuberculin test (SICTT) positive goats were recruited. Additionally, 286 SICTT negative goats classed as potentially exposed animals present in the same positive herds were also included in the study. The results of the assay demonstrated a specificity of 100%. The multiplex assay detected 57/60 SICTT (95.0%) positive animals in one M. bovis infected herd and 120/120 (100%) in a second herd. In a separate experiment, 28 M. caprae culture confirmed infected goats from Spain were assayed, of which 24 (85.7%) were found positive in the test. The results show that inclusion of an antibody based assay can improve the ability to identify M. bovis and M. caprae infected goats. With further development and validation the multiplex assay may prove to be a useful tool for control of M. bovis and M. caprae infection in goats.  相似文献   
147.
148.
(1)H HR-MAS NMR spectroscopy was applied to apple tissue samples deriving from 3 different cultivars. The NMR data were statistically evaluated by analysis of variance (ANOVA), principal component analysis (PCA), and partial least-squares-discriminant analysis (PLS-DA). The intra-apple variability of the compounds was found to be significantly lower than the inter-apple variability within one cultivar. A clear separation of the three different apple cultivars could be obtained by multivariate analysis. Direct comparison of the NMR spectra obtained from apple tissue (with HR-MAS) and juice (with liquid-state HR NMR) showed distinct differences in some metabolites, which are probably due to changes induced by juice preparation. This preliminary study demonstrates the feasibility of (1)H HR-MAS NMR in combination with multivariate analysis as a tool for future chemometric studies applied to intact fruit tissues, e.g. for investigating compositional changes due to physiological disorders, specific growth or storage conditions.  相似文献   
149.
This paper describes an outbreak of tuberculosis (TB) caused by Mycobacterium bovis in a dairy goat herd on a farm in Ireland, where 66.3 per cent of the herd tested positive to the single intradermal comparative tuberculin test (SICTT) at initial detection. An epidemiological investigation was conducted to determine the origin of the outbreak, considering issues such as animal movements and herd management practices. Infection was introduced with a consignment of goats, as determined by the variable number tandem repeat profile. Infection was eradicated using a test and cull programme involving the SICTT, the interferon-γ assay and a multiplex immunoassay (Enferplex TB).  相似文献   
150.
Ireland currently obtains its avian and bovine tuberculin purified protein derivatives (PPDs) from a single source. Because problems of supply or quality cannot be discounted, it is prudent that Ireland identify alternative supplier(s) as part of a broad risk management strategy. Therefore, the aim of this study was to compare the performance of a number of different tuberculin combinations (that is, pairings of bovine and avian PPD; with different manufacturers) in the single intradermal comparative tuberculin test (SICTT), as currently performed in Ireland. The study was randomised, controlled and double-blinded. A total of 2172 cattle were used in the study. Each animal was tested using two SICTTs, the first based on the tuberculin combination in current use, and the second using one of six trial tuberculin combinations. Analyses were conducted to compare both reactor-status and skin increase. For each control/trial tuberculin combination, there was good agreement between the control and trial reactor-status. Differences in skin increases were mainly confined to animals categorised as either negative or severe inconclusive. However, the measured differences were minor, and unlikely to have a significant impact on the actual test outcome, either for individual animals or for herds. In conclusion, while further studies determining sensitivity and specificity in Ireland would have to be done in the event of a change in tuberculin PPD there should be minimal disruption of the national programme if alternative tuberculin PPDs meeting WHO, OIE and EU regulations were used. In this study, the precision of the guinea pig bio-assay to assess tuberculin potency was low and therefore Ireland should maintain its practice of periodically assessing potency in naturally infected cattle, even though this is not currently required under WHO, OIE or EU Regulations.  相似文献   
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