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91.
This paper presents a method for characterizing the complexity of landscape boundaries by remote sensing. This characterization is supported by a new boundary typology, that takes into account points where three or more landcovers converge (i.e., convergency points or coverts). Landscape boundary richness and diversity indices were proposed and calculated over 19 landscapes in South-East Brazil. Results showed that landscape boundaries, especially convergency points, provided an enrichment in landscape pattern analysis. Landcover boundary diversities were significantly related to landcover shape: elongated riparian units had the highest values for boundary diversity and coverts proportion indices. On the other hand, landscape analysis showed that indices of shape, richness, diversity and coverts proportion provided an additional evaluation of landcover spatial distribution within the landscape. 相似文献
92.
Isotype-specific antibodies in horses and dogs with immune-mediated hemolytic anemia 总被引:1,自引:1,他引:0
Wilkerson MJ Davis E Shuman W Harkin K Cox J Rush B 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2000,14(2):190-196
Classes of antibody bound to erythrocytes were determined using direct immunofluorescence (DIF) flow cytometry in 3 horses and 12 dogs with immune-mediated hemolytic anemia (IMHA). Background levels of antibody binding were determined in samples from 12 horses and 12 dogs that were free of clinical disease. The range of nonspecific binding of a fluorescein isothiocyanate (FITC)-conjugated goat anti-equine immunoglobulin G (IgG) was 19.9–36.7%, but was eliminated by the use of the F(ab)2 fragment of FITC-conjugated goat anti-equine IgG. Background binding by other class-specific antibodies to equine and canine erythrocytes was negligible. The DIF results were compared to the direct antiglobulin (Coombs) test in 5 horses and 20 dogs with anemia. The former assay was more sensitive in dogs with IMHA than was the Coombs' test (100% versus 58%). In contrast, the Coombs' test had better specificity than the DIF assay (100% versus 87.5%, respectively). Using clinical parameters or response to therapy as the comparison, the positive and negative predictive values for the DIF test were 92% and 100% compared to the values of the Coombs' test of 100% and 62%. The DIF assay detected low levels of cells bound with antibody (<30%) in 5 dogs that were Coombs' test-negative. For both species, performance of the DIF test was independent of the prozone effect. Five dogs with IMHA had IgG and IgM on erythrocytes, 5 had IgG, and 2 had IgM. Three horses had surface-bound IgG, including a horse with suspected penicillin-induced IMHA, a foal with neonatal isoerythrolysis, and a foal with clostridial septicemia. The DIF method was valuable in monitoring the response to therapy in the foal with neonatal isoerythrolysis. 相似文献
93.
SANTI WONGAUMNUAYKUL CLAUDIA SIEDLER HERMANN SCHOBESBERGER CHRISTIAN STANEK 《Veterinary radiology & ultrasound》2006,47(2):199-205
The aim of this study was to evaluate the use of Doppler ultrasonography to monitor vascular blood flow dynamics in defined diseases of the equine digit in a noninvasive way. Doppler sonography was used to evaluate medial digital artery blood flow in eight horses with septic pododermatitis and four horses with laminitis in comparison with 10 horses of a control group. Doppler sonographic measurement and lameness examinations were performed in lame horses before treatment (day 0) and at 3, 6, and 9 days following treatment. Before treatment, blood flow velocities, arterial diameter, and flow volume were significantly higher in the lame horses, while pulsatility indices (PIs) were significantly lower (P < 0.05). Compared with the control group, there was no significant difference of resistive indices (RI) in the septic pododermatitis group, but these indices were significantly lower in the laminitis group. No significant difference between the two lame groups was recorded. After treatment, blood flow velocities and flow volume decreased significantly and PIs increased significantly in both lame groups, while RI and arterial diameter did not change. No correlation between Doppler parameters and the degree of lameness was found. Doppler sonography can be used to monitor vascular blood flow dynamics in horses suffering from septic pododermatitis and laminitis, while blood flow velocities and PI can serve as parameters for monitoring the course of the disease. 相似文献
94.
东北白鹅和籽鹅血液生化指标 总被引:5,自引:2,他引:5
为建立东北白鹅和籽鹅血液生化指标的正常参考值及其正常参考范围,探讨东北白鹅和籽鹅的各项血液生化指标之间的差异显著性,随机抽取(12±0.5)月龄健康、体质量为(4.2±0.2)kg的东北白鹅母鹅和(3.5±0.2)kg的籽鹅母鹅各65只,空腹12h后翅下静脉采血,离心分离血清,应用半自动生化分析仪及试剂盒对血清22项生化指标进行检测分析。结果表明:东北白鹅和籽鹅丙氨酸氨基转移酶(ALT/GPT)、天门冬氨酸氨基转移酶(AST/GOT)、谷氨酸酰基转移酶(GT)、胆碱脂酶(CHE)、乳酸脱氢酶(LDH-L)、葡萄糖(Glu)、高密度脂蛋白胆固醇(HDL-C)、总蛋白(TP)、白蛋白(Alb)、钙(Ca)、肌酐(Cre)、镁(Mg)等血清生化指标之间差异达到极显著水平(P<0.01);碱性磷酸酶(ALP)、总胆固醇(CHO)、无机磷(P)之间差异达到显著水平(P<0.05);a-羟丁酸脱氢酶(a-HBDH)、尿素氮(BuN)、甘油三脂(TG)、尿酸(UA)、总胆红素(T.Bili)、直接胆红素(D.Bili)、氯(Cl)之间无显著性差异(P>0.05)。本试验建立的东北白鹅和籽鹅血液生化指标的正常参考值及其正常参考范围,为今后鹅的相关研究提供了基础的科学数据和基本的理论依据。 相似文献
95.
《Communications in Soil Science and Plant Analysis》2012,43(3-4):397-412
Abstract Relations among the expression of banana disease symptoms caused by the soil fungus Fusarium oxysporum f. sp. cubense, soil potassium (K)–sodium (Na) properties [soluble K‐Na ratios (SK/SS), potential buffering capacity for K (KBC), potassium adsorption ratio (KAR)], and clay‐sized particles were evaluated in Sorribas plots from the Canary Islands. Soils were sampled in areas of Sorribas where banana plants show positive or negative wilting symptoms characteristic of Panama disease. The Bartoli method was used for soil dispersion (Na resin). This method was able to show a clear separation between diseased and disease‐free areas by the amount of clay‐sized particles. Results also show that the greatest SK/SS ratios and clay‐sized particles in soils from diseased areas could explain the increase of water‐stable aggregate mass in these soils and the release of available iron (Fe) to soil solution in diseased areas, at least in Sorribas cultivated soils under the arid climate conditions of the Canary Islands. 相似文献
96.
试验初步研究了皂质芦荟细胞悬浮培养过程.比较了不同基本培养基、接种量对悬浮培养过程中细胞生长量的影响.采用正交设计方法,对影响皂质芦荟悬浮细胞生长的因素进行了优化研究.初步探讨了皂质芦荟在细胞生长周期里生理生化特性.结果表明:B5 培养基有利于细胞的增殖;每50 mL培养液中加入2 g愈伤组织的接种量为宜;筛选出最适激素组合为2,4-D 3.0mg/L KT0.5mg/L,葡萄糖25 g/LpH值5.8;皂质芦荟悬浮培养的生长周期为25 d,细胞增值率曲线呈S型;在悬浮细胞生长前期,pH值明显下降,在细胞对数生长期,pH值略有升高,并趋于平缓;总酚含量、POD、SOD均出现2个峰值,但出现时间不同,其变化趋势与细胞生长趋势呈正相关,PPO活性与细胞生长趋势呈负相关. 相似文献
97.
应用红细胞C3b受体花环(C3bRR)和免疫复合物花环(ICR)试验,证实鸵鸟红细胞表面存在补体C3b受体(C3breceptor,C3bR),表明红细胞免疫系统(Rcdcelimmunesystem,RCIS)的概念亦适用于这种动物;鸵鸟红细胞不但有传统医学观念上的功能,而且还可借助CR1(ComplementreccptortypeI)进行免疫粘附,并以此为基础,表现出各种重要的免疫功能。 相似文献
98.
J M PEÑA-BARRAGÁN F LÓPEZ-GRANADOS M JURADO-EXPÓSITO & L GARCÍA-TORRES 《Weed Research》2007,47(2):164-172
Ridolfia segetum is a frequent umbelliferous weed in sunflower crops in the Mediterranean basin. Field and remote sensing research was conducted in 2003 and 2004 over two naturally infested fields to determine the potential of multispectral imagery for discrimination and mapping of R. segetum patches in sunflower crops. The efficiency of the four wavebands blue (B), green (G), red (R) and near‐infrared (NIR), selected vegetation indices and the spectral angle mapper (SAM) classification method were studied using aerial photographs taken in the late vegetative (mid‐May), flowering (mid‐June) and senescence (mid‐July) crop growth stages. Discrimination efficiency of R. segetum patches in sunflower crops is consistently affected by their phenological stages, in this order: flowering > senescence > vegetative. In both fields, R. segetum patches were efficiently discriminated in mid‐June, corresponding to the flowering phase, by using the waveband G, the ratio R/B or SAM with overall accuracies ranging from 85% to 98%. The application of the median‐filtering algorithm to any of the classified images improved the accuracy. Our results suggest that mapping R. segetum weed patches in sunflower to implement site‐specific weed management techniques is feasible with aerial photography when images are taken from 8 to 10 weeks before harvesting. 相似文献
99.
100.
【目的】 研究饲粮粗蛋白质水平对26~45日龄竹丝公鸡生长性能、胴体性状和血清生化指标的影响,为此生长阶段粗蛋白质精准供给提供理论基础。【方法】 1 625只26日龄竹丝肉公鸡根据体重一致原则分为5个处理组,每个处理组5个重复,每个重复65只鸡,各处理组饲粮粗蛋白质水平依次为18.5%、19.5%、20.5%、21.5%和22.5%,试验期20 d。每个重复于试验结束当天挑选接近平均体重的2只鸡屠宰,制备血清和分割屠体,测定胴体性状和血清生化指标。【结果】 ①饲粮粗蛋白质水平极显著影响肉鸡终末体重、平均日增重和料重比(P<0.01),随着粗蛋白质水平的升高,终末体重和平均日增重呈线性和二次曲线升高(P<0.01),料重比呈线性和二次曲线降低(P<0.01)。饲粮粗蛋白质水平对肉鸡平均日采食量和成活率无显著影响(P>0.05)。②饲粮粗蛋白质水平显著或极显著影响肉鸡屠宰率(P<0.01)、半净膛率(P<0.01)和全净膛率(P<0.05),但对胸肌率、腿肌率和腹脂率无显著影响(P>0.05),且屠宰率和半净膛率随粗蛋白质水平的升高呈线性和二次曲线降低(P<0.01或P<0.05)。③饲粮粗蛋白质水平极显著影响肉鸡血清胰岛素样生长因子1(IGF-1)和胆固醇(TC)含量(P<0.01),且TC含量随粗蛋白质水平的升高呈线性降低(P<0.05)。饲粮粗蛋白质水平对肉鸡血清尿素氮(BUN)和甘油三酯(TG)含量无显著影响(P>0.05)。【结论】 饲粮21.5%粗蛋白质水平可改善肉鸡生长性能,19.5%~20.5%粗蛋白质水平可改善胴体性状,18.5%粗蛋白质水平可调节脂代谢。根据二次曲线模型估测,建议此生长阶段竹丝鸡饲粮粗蛋白质水平为21.41%~21.83%,可获得最佳生长性能。 相似文献