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991.
992.
Giguère S Knowles HA Valverde A Bucki E Young L 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2005,19(4):571-576
The objectives of this study were to assess, in anesthetized neonatal foals, the accuracy of 2 automated indirect oscillometric monitors for measurement of mean arterial pressure (MAP), to determine the optimal site of cuff placement for MAP monitoring, and to determine the relationship between arterial blood pressure and cardiac output. Ten neonatal foals were anesthetized and instrumented with a catheter in the metatarsal artery for direct MAP monitoring and measurement of cardiac output by lithium dilution. Concurrent MAP measurements were obtained with Cardell and Dinamap oscillometric monitors with cuffs placed at 3 different sites (coccygeal, metatarsal, and median arteries). Blood pressure was manipulated by varying the depth of anesthesia and by administration of dobutamine or phenylephrine. A statistically significant (P = .025) interaction was found between the type of monitor and cuff placement site. With the Cardell monitor, placement of the cuff over the coccygeal artery resulted in a significantly lower bias than placement over the median or dorsal metatarsal artery (P < .0001 and P = .0149, respectively). No significant difference in bias was found with cuff placement site when using the Dinamap monitor. The correlation coefficient (r) between MAP and cardiac output was 0.47. Indirect oscillometry with a cuff placed over the coccygeal artery or dorsal metatarsal artery is an acceptable method for measuring MAP in foals. Blood pressure does not correlate well with cardiac output in anesthetized foals. 相似文献
993.
Detection of bovine leukemia virus in blood and milk by nested and real-time polymerase chain reactions. 总被引:2,自引:0,他引:2
Christopher J Kuckleburg Christopher C Chase Eric A Nelson Salvatore A E Marras Matthew A Dammen Jane Christopher-Hennings 《Journal of veterinary diagnostic investigation》2003,15(1):72-76
Concerns about retroviruses in livestock and products derived from them have necessitated the development of tests to detect the bovine leukemia virus (BLV) in blood and milk from cattle. Dairy cattle (n = 101) from 5 different geographical areas were used for this study. A nested polymerase chain reaction (PCR) identified 98% of BLV seropositive cattle (n = 80) from blood and 65% from milk, whereas real-time PCR detected 94% of BLV seropositive cattle from blood and 59% from milk. Bovine leukemia virus was also detected by PCR in approximately 10% of seronegative cattle (n = 21), most likely because of early detection before seroconversion. 相似文献
994.
Jane Christopher-Hennings Matthew A Dammen Shelleen R Weeks William B Epperson Shri N Singh Gina L Steinlicht Ying Fang Jessica L Skaare Jill L Larsen Janet B Payeur Eric A Nelson 《Journal of veterinary diagnostic investigation》2003,15(2):87-93
In this study, 5 combinations of 2 DNA extractions and 3 polymerase chain reaction (PCR) techniques were compared with culture for the detection of Mycobacterium paratuberculosis directly from bovine feces. These combinations included a new commercial extraction technique combined with a commercial PCR/Southern blot technique, nested PCR (nPCR), or real-time PCR, and a university-developed extraction combined with nPCR or real-time PCR. Four of the 5 combinations had statistically similar sensitivities between 93% and 100% and specificity between 95% and 100%, when compared with culture results from 63 bovine fecal samples. These results indicated that using a commercial extraction with a commercial PCR/Southern blot, nPCR, or real-time PCR, or a university-developed extraction with real-time PCR would result in similar sensitivities to culture for the identification of M. paratuberculosis from bovine feces and are valid alternatives to culture. 相似文献
995.
Luis R Padilla Kathryn P Huyvaert Jane Merkel R Eric Miller Patricia G Parker 《Journal of zoo and wildlife medicine》2003,34(3):278-283
Venipuncture was performed on 50 adult, free-ranging waved albatrosses (Phoebastria irrorata) on Espa?ola, Galapagos Islands, Ecuador, to establish hematologic and plasma biochemistry reference ranges and to determine the prevalence of exposure to important domestic avian pathogens. Weights and plasma creatine phosphokinase activities differed significantly between males and females. Serum was tested for evidence of exposure to avian influenza, avian paramyxoviruses 1, 2, and 3, avian cholera, adenovirus groups 1 and 2, avian encephalomyelitis, Marek's disease, infectious bursal disease, and infectious bronchitis virus (Connecticut and Massachusetts strains). Of 44 birds, 29 (66%) seroreacted to adenovirus group 1, and four seroreacted to avian encephalomyelitis. Cloacal swabs were negative for Chlamydophila psittaci DNA. 相似文献
996.
Eric M. Green DVM Lisa J. Forrest VMD William M. Adams DVM 《Veterinary radiology & ultrasound》2003,44(4):476-479
This prospective study was undertaken to compare the positioning repeatability and setup time of a rigid immobilization device (Vac-Lok mattress) to conventional positioning methods (sandbags, tape, foam wedges) in the clinical veterinary radiotherapy setting. Positioning repeatability was determined by using port films to verify appropriate patient positioning. Setup time was determined by recording the time required to set up each patient using each positioning method. Sixty-seven patients receiving radiotherapy were positioned using both the Vac-Lok mattresses and conventional positioning methods during their treatments. Seventy-eight total sites were treated. Forty-eight were treated daily (Monday through Friday, 2 to 4 weeks) and 30 were treated once weekly (4 weeks). Patients were grouped according to the site treated: head (29), neck/body (24), and limb (25). Vac-Lok mattresses were similar to conventional means in positioning repeatability and setup time. Vac-Lok mattresses are potentially advantageous in specific situations, including use during pre-radiotherapy tumor imaging. These mattresses are not recommended for distal limb positioning. 相似文献
997.
Eric R Pope 《Veterinary Clinics of North America: Small Animal Practice》2006,36(4):793-817
Injuries to the head and facial area are common in small animal surgery. Although many of the injuries at first may seem formidable, most can be repaired using basic reconstructive surgery procedures. The excel-lent blood supply in this area and the availability of local tissues provide many options for repairing most wounds. This article describes the indications and techniques for reconstructing wounds in this area. 相似文献
998.
James E. Smallwood DVM MS Brett C. Wood DVM MEM W. Eric Taylor DVM Lloyd P. Tate Jr. VMD 《Veterinary radiology & ultrasound》2002,43(2):99-117
The purpose of this study was to produce an anatomic reference for computed tomography (CT) of the head of the foal for use by radiologists, clinicians, and veterinary students. The head from each of 2 foals, euthanized for reasons unrelated to head pathology, was removed and prepared for CT scanning. Using a third-generation CT scanner, 5-mm contiguous transverse images were acquired. The heads were then frozen and sectioned using a band saw, with the cuts matched as closely as possible to the CT slices. The anatomic sections were photographed and radiographed. The radiographs and anatomic photographs were digitized and matched with the corresponding CT image. Each CT image was compared with its corresponding radiographic and anatomic section to assist in the accurate identification of specific structures. Clinically relevant structures were identified and labeled in corresponding images (CT, anatomic slice, and radiograph of slice). Only structures identified in the CT image were labeled in 1 of the other 2 images. Sagittal (reference) images of the horse's head were reconstructed from the transverse CT scans, and were used to indicate the level from which each of the transverse images was obtained. Corresponding labeled images were then formatted together with a legend for identification of specific anatomic structures. 相似文献
999.
Damien Bonal Céline Born Claude Brechet Sabrina Coste Eric Marcon Jean-Christophe Roggy Jean-Marc Guehl 《Annals of Forest Science》2007,64(2):169-176
We characterised the among species variability in leaf gas exchange and morphological traits under controlled conditions of seedlings of 22 tropical rainforest canopy species to understand the origin of the variability in leaf carbon isotope discrimination (Δ) among species with different growth and dynamic characteristics (successional gradient). Our results first suggest that these species pursue a consistent strategy in terms of Δ throughout their ontogeny (juveniles grown here versus canopy adult trees from the natural forest). Second, leaf Δ was negatively correlated with WUE and N, and positively correlated with gs, but among species differences in Δ were mainly explained by differences in WUE. Finally, species belonging to different successional groups display distinct leaf functional and morphological traits. We confirmed that fast growing early successional species maximise carbon assimilation with high stomatal conductance. In contrast, fast and slow growing late successional species are both characterised by low carbon assimilation values, but by distinct stomatal conductance and leaf morphological features. Along the successional gradient, these differences result in much lower Δ for the intermediate species (i.e. fast growing late successional) as compared to the two other groups. 相似文献
1000.
Craig M. Hardner Calvin W. Winks Russ A. Stephenson Eric G. Gallagher Cameron A. McConchie 《Euphytica》2002,125(2):255-264
Broad-sense heritability, and genetic and phenotypic correlations were estimated for yield (nut-in-shell; kernel yield; and
net present value of crop) per tree in macadamia to 10 years after planting from a trial of 40 cultivars replicated over 4locations.
In addition, canopy width at 10years of age was measured and used to calculate yield efficiency as yield per square metre
of projected canopy area. Stem girth above the graft union was also measured. There was a low broad-sense heritability (0.06
< H <0.22) and correlation of cultivars across locations (r
gloc = 0.14–0.52) for yield per tree. However, the genetic correlation of cumulative yield was high among 3 of the 4locations
(g ≥ 0.75), suggesting the higher genetic variance at Rockhampton was the main cause of the genotype by environmental interaction.
Heritability was higher for canopy width (H = 0.28) and yield efficiency (H ≈ 0.47) and cultivar performance was highly correlated across locations (r
gloc ≈ 0.70) for these traits. There was a strong genetic correlation (r
g ≥ 0.90) between cumulative yield per tree of cultivars to 7 years and cumulative yield per tree to 10 years. Genetic correlation
among all measures of yield per tree were high (r
g ≥ 0.73), but there was no genetic correlation with canopy width. On the other hand, small cultivars tended to have higher
yield efficiency (r
g <–0.62). There was also a slight negative correlation between nut-in-shell yield per tree and kernel recovery (r
g = –0.37). These results suggest the use of family information and index selection may improve the efficiency of selection
and breeding programs in macadamia.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献