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51.
The operational planting stock quality testing program at Weyerhaeuser   总被引:5,自引:0,他引:5  
Tanaka  Y.  Brotherton  P.  Hostetter  S.  Chapman  D.  Dyce  S.  Belanger  J.  Johnson  B.  Duke  S. 《New Forests》1997,13(1-3):423-437
The value of the Seedling Testing System (STS) is five-fold. First, it minimizes the utilization of poor quality stock that might result in regeneration failure. Second, it assists nursery managers in estimating cold hardiness of seedlings in support of the nursery frost control program. Third, it helps prevent crop losses due to pathological problems in the greenhouse and nursery. Fourth, it helps the nursery staff develop good working relationships with outside customers who benefit from the testing service. Fifth, it is a valuable tool for the nursery and tree improvement research program.  相似文献   
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During MESSENGER's first flyby of Mercury, the Mercury Atmospheric and Surface Composition Spectrometer made simultaneous mid-ultraviolet to near-infrared (wavelengths of 200 to 1300 nanometers) reflectance observations of the surface. An ultraviolet absorption (<280 nanometers) suggests that the ferrous oxide (Fe2+) content of silicates in average surface material is low (less than 2 to 3 weight percent). This result is supported by the lack of a detectable 1-micrometer Fe2+ absorption band in high-spatial-resolution spectra of mature surface materials as well as immature crater ejecta, which suggests that the ferrous iron content may be low both on the surface and at depth. Differences in absorption features and slope among the spectra are evidence for variations in composition and regolith maturation of Mercury's surface.  相似文献   
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Severe diaphragmatic necrosis occurred in horses with degenerative myopathy due to polysaccharide storage myopathy (n = 2), nutritional myopathy (n = 1), and vasculitis (n = 1). Blood gas analysis performed in 1 horse indicated development of respiratory acidosis. Respiratory muscle necrosis can be severe in horses with degenerative myopathy and can lead to respiratory failure.  相似文献   
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Objective— To report fertility (foals conceived, live foal births) of mares after partial fetotomy to resolve dystocia and complications associated with fetotomy.
Study Design— Retrospective study.
Animals— Horses (n=20).
Methods— Medical records (2001–2006) of mares that had partial fetotomy (1–3 cuts) for dystocia were reviewed. Complications and subsequent fertility were obtained by interview and live foal data were recorded by the Jockey Club. Postfetotomy conception and live foals produced over 21 breeding seasons (defined as years each mare was bred regardless of conception) were recorded.
Results— Twenty mares were identified. Bilateral carpal flexion alone (3 mares) or in combination with another deformity (7 mares) was the most common presentation for dystocia. From 2001 to 2006, there were 24 breeding seasons for which 20 mares conceived (83%). Eighteen mares conceived before 2006 and all produced live foals. Three mares were bred in 2006; 2 became pregnant, 1 was electively aborted, and 1 is pregnant. Eight of 19 (42%) mares had retained placenta, which were expelled within 24 hours after medical therapy.
Conclusion— Partial fetotomy performed with 1–3 cuts does not impede a successful reproductive future.
Clinical Relevance— In selected equine dystocia cases, partial fetotomy should be given primary consideration when the foal is dead and vaginal delivery cannot be readily achieved. Fetotomy should not adversely affect the future fertility of the mare.  相似文献   
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Relatively little is known about how growth as a biofilm affects the virulence of pathogenic bacteria. In this study, the virulence of Salmonella typhimurium grown as a biofilm, or as planktonic cells, was compared in mice. Increased numbers of colony forming units were recovered from the spleens of mice 5 days after i.p. injection with S. typhimurium grown as a biofilm, as compared with planktonic cells (P < 0.05). No significant difference in the CFU of S. typhimurium recovered from the liver was noted at the same time point, and no difference was noted in the CFU recovered from the spleen or liver at 5 days after i.v. or i.g. inoculation with 10(5) S. typhimurium. Nor were any differences noted at 7 days after i.p., i.v. or i.g. inoculation. Thus, any effect of growth as a biofilm has on the virulence of S. typhimurium seems to be limited to the first 5 days after i.p. inoculation.  相似文献   
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OBJECTIVE: To evaluate the relationship of colonic luminal pressure (CLP) measurements to outcome in horses with large colon volvulus (LCV) after either manual correction or large colon resection and anastomosis (LCRA). STUDY DESIGN: Retrospective study. ANIMALS: Horses (n=57) that had LCV. METHODS: Records for horses with LCV (March 1997-December 2003) were reviewed. Inclusion criteria were strangulating LCV proximal to the cecocolic ligament (>270 degrees), recorded CLP, and successful recovery from anesthesia. CLP measurements and survival/mortality rates were compared between horses that had manual correction (M) or LCRA (R). RESULTS: Of 57 horses, 27 had M and 30 had LCRA. For group M, CLP measurements had a sensitivity of 0.60 and specificity of 0.77 for predicting survival, whereas for group R, sensitivity was 0.50 and specificity was 0.54. CONCLUSION: In our LCV population, elevated CLP measurements had poor accuracy for predicting outcome in horses after surgical correction, especially after LCRA. CLINICAL RELEVANCE: CLP measurements based on a single hospital population of horses with LCV should be used with caution for other hospital populations of LCV. CLP may be only one of many variables needed for predicting outcome of horses with strangulating LCV, especially after LCRA.  相似文献   
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