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121.
Daugherty MA Leib MS Lanz OI Duncan RB 《Journal of the American Veterinary Medical Association》2006,229(6):975-979
CASE DESCRIPTION: An 8-year-old male Golden Retriever was evaluated because of an 8-week history of intermittent diarrhea with melena and hematochezia that were not responsive to medical treatment and resulted in severe anemia. CLINICAL FINDINGS: Exploratory celiotomy with intestinal and colonic biopsy revealed mild enterocolitis but did not result in diagnosis of the cause of melena and hematochezia. Endoscopy of the upper portion of the gastrointestinal tract and colonoscopy were performed. Multifocal areas of coalescing, tortuous mucosal blood vessels were observed in the cecum and all regions of the colon. A diagnosis of vascular ectasia (VE) was made on the basis of the endoscopic and histologic appearance of the lesions. TREATMENT AND OUTCOME: An ileorectal anastamosis was performed. Melena and hematochezia resolved within 3 days after surgery, and the anemia resolved within 6 weeks after surgery. Surgical resection of the cecum and colon and feeding of a highly digestible diet resulted in long-term (22 months) resolution of clinical signs. CLINICAL RELEVANCE: Initial exploratory celiotomy with intestinal and colonic biopsy failed to reveal the VE lesions responsible for the melena, hematochezia, and anemia. Endoscopic evaluation was necessary for detection of the colonic VE lesions. Surgical resection of the cecum and colon and feeding of a highly digestible diet may result in a favorable outcome in affected dogs. 相似文献
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The acquired immunity consists of two pathways namely the humoral immunity that defends the host against extracellular pathogens such as bacteria and the cell-mediated immunity that defends the host against intracellular pathogens such as Mycobacterium tuberculosis and viruses and also against cancers. The aim of this study is to determine the effects of river water collected from pristine and contaminated sites along the Eerste River, South Africa on inflammation, humoral and acquired immune pathways. Hydrophobic extracts were prepared from water collected at contaminated and pristine sites. Inflammatory activity was determined by measuring interleukin (IL)-6 levels synthesized by whole blood after incubation with the extracts. For determining the effects on acquired immunity, phytohemagglutinin stimulated whole blood from healthy volunteers was incubated with extracts. The effect on humoral immunity was determined using IL-10 as biomarker, while interferon-gamma was used as biomarker for cell-mediated immunity. The results obtained show that water from the sites downstream from human activity induced IL-6, a biomarker of inflammation. Extracts collected from a site downstream from an informal housing settlement suppressed biomarkers of both humoral and cell-mediated immunity. Water from sites impacted by human activity can potentially suppress the acquired immune system and this can pose a health risk to people using this water source. Studies must be done to investigate the long-term effects of the contaminated water on animals in vivo. 相似文献
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125.
S.D. Kemp K.L. Zimmerman D.L. Panciera W.E. Monroe M.S. Leib 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2015,29(1):58-62
Background
Biopsy of the liver evaluates a small portion of tissue, with inferences made to the entire organ. The method and number of biopsies obtained are tempered by consideration of the risks and benefits. Recommendations often include biopsy of more than one liver lobe, although the consistency of histopathology among lobes in dogs is unknown.Hypothesis/Objectives
To describe the distribution of histopathologic abnormalities between liver lobes. We hypothesized that discordant results would be evenly distributed among all liver lobes.Animals
Seventy dogs undergoing necropsy.Methods
Prospective study. Liver samples were obtained from all lobes. A primary diagnosis was assigned to each liver sample based on the predominant histopathologic abnormality.Results
In this population of dogs, biopsy of at least 2 liver lobes identified the predominant histologic abnormality in 98.6% of the cases. Ten (14%) of the dogs had ≤3 lobes in agreement and could not be assigned a predominant diagnosis. The same diagnosis was present in 6/6 lobes in 39 (56.5%) dogs, 5/6 lobes in 10 (14.5%) dogs, 4/6 lobes in 10 (14.5%) dogs, 3/6 lobes in 7 (10.1%) dogs, and 2/6 in 3 (4.3%) dogs. The number of discordant results did not differ between the liver lobes.Conclusion and Clinical Importance
The likelihood of obtaining a sample that is reflective of the predominant histologic abnormality in the liver is increased when multiple liver lobes are biopsied. 相似文献126.
Sediment control structures constructed at the heads of run-of-river irrigation schemes have little effect on the very fine sands and silts that settle in the smaller distribution canals. One means of minimising the effects of fine sediment deposition in small canals is to design canals so that deposition occurs at selected locations, rather than throughout the canal network. Standard sediment transport predictors cannot be used to predict the effects of changing canal slopes and cross sections when sediment sizes are very small, and thus cannot be used to determine dimensions and slopes of small canal settling basins.The paper presents a simple method for estimating the transport and deposition rates of fine sediment suspensions, for sediments in the cohesive size range. The method, which has been tested against a large data set, enables the effects of changing canal cross sections and slopes on fine sediment transport to be quantified. 相似文献
127.
Brian G. Leib Horst W. Caspari Cristoti A. Redulla Preston K. Andrews Jalal J. Jabro 《Irrigation Science》2006,24(2):85-99
The effects of deficit irrigation (DI) and partial rootzone drying (PRD) on apple (Malus domestica Borkh. Cv. ‘Fuji’) yield, fruit size, and quality were evaluated from 2001 to 2003 in the semi-arid climate of Washington
State. PRD and DI were applied from about 40 days after full bloom until just before (2001, 2002) or after (2003) harvest
and compared to a control irrigation (CI). Irrigation was applied once a week using two micro-sprinklers per tree. Soil-water
content in CI was maintained above 80% of field capacity using micro-sprinklers on both sides of a tree. The DI and PRD were
irrigated at about 50% (2001–2002) and 60% (2003) of the CI, but differed in placement of irrigation. For DI both micro-sprinklers
were operated whereas PRD was irrigated using only one micro-sprinkler wetting half the rootzone compared to CI and DI. Wetting/drying
sides of PRD trees were alternated every 2–4 weeks (2001, 2002) or when soil-water content on the drying side had reached
a threshold value (2003). Seasonal (1 May–31 October) potential evapotranspiration (ET0) was 967, 1002, and 1005 mm for 2001, 2002, and 2003, and rainfall totaled 58, 39, and 21 mm, respectively. Irrigation amounts
applied were 596, 839, and 685 mm in the CI; 374, 763, and 575 mm in the DI; and 337, 684, and 513 mm in the PRD for the 2001,
2002, and 2003 seasons. Higher irrigation volumes in 2002 were due to excessive (177–324 mm) irrigations after harvest. No
significant differences were found in yield and fruit size among treatments in 2001 and 2003. In 2002, DI had significantly
lower yield than CI, while the yield of PRD did not differ from CI and DI. Fruit from DI and PRD were firmer and had higher
concentrations of soluble solids than fruit from CI, both at harvest and following short-term storage at 20°C, but differences
to CI were significant in 2002 only. Treatment effects on fruit titratable acidity were inconsistent. Additional water was
preserved in the soil profile under PRD compared to DI in 2001 and 2003, but no statistical differences were found between
PRD and DI in 2002. Approximately 45–50% of irrigation water was saved by implementing newly developed DI and PRD irrigation
strategies without any significant impact on fruit yield and size with PRD. However, apple yield was reduced by DI compared
to CI in the second year. 相似文献
128.
【目的】探讨IP3信号通路是否会影响肥胖小鼠细胞内的钙离子浓度以及钙信号对肥胖小鼠脂肪代谢的作用机制,进一步了解胞内钙离子浓度变化对脂肪代谢的作用机理。【方法】用高脂日粮饲喂小鼠30d以建立肥胖模型,将肥胖小鼠分为对照组、去甲肾上腺素(NE)组、肝素组、钙组、钙+NE组和钙+肝素组,除对照组和钙组外的各药物组小鼠分别给予相应的药物处理,腹腔注射质量浓度0.1mg/mL的NE或1.5mg/mL的肝素0.2mL/(只.d);对照组和钙组同法给予等体积的生理盐水。对照组、NE组和肝素组小鼠饲喂普通日粮,钙组、钙+NE组和钙+肝素组小鼠饲喂加钙饲粮(钙含量12g/kg),小鼠共饲喂16d,期间每3d测1次体质量,17d时禁食12h,摘眼球取血后脱颈椎处死,分离血清检测其中甘油三酯(TG)、总胆固醇(TC)和高密度脂蛋白(HDL-C)的浓度,并取脂肪组织,测定附睾脂肪和肾周脂肪组织质量,分析附睾脂肪、肾周脂肪和肝脏的钙含量。通过RT-PCR法分析与脂肪生成密切相关的转录因子PPARγ、C/EBPα和脂解基因HSL及生脂基因FAS mRNA的表达水平,检测IP3受体IP3R1的mRNA表达水平。【结果】肝素和膳食钙处理对肥胖小鼠有极显著的减肥效果(P<0.01),可极显著减少体脂质量(P<0.01),降低血清中TG和TC浓度(P<0.01),而HDL-C浓度极显著升高(P<0.01),肝素和膳食钙处理肥胖小鼠的PPARγ、FAS和IP3R1的mRNA水平均极显著降低(P<0.01),HSL mRNA水平极显著升高(P<0.01),C/EBPα的mRNA水平无明显变化;NE处理对肥胖小鼠的作用效果与肝素相反,其可明显削弱减肥作用(P<0.01)。膳食钙有显著的减肥效果(P<0.01),但钙+NE组的减肥效果弱于钙组(P<0.01),钙+肝素组的减肥效果强于膳食钙的处理效果(P<0.01)。【结论】IP3通路激活可引起胞内钙离子浓度升高,脂肪蓄积增加;反之,脂肪蓄积减少。通过IP3通路,膳食钙可抑制胞内钙离子增加。 相似文献
129.
130.