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71.
A 10-month-old Arabian foal was evaluated for a suspected immunoglobulin (Ig) M deficiency. Decreased to nondetectable concentrations of IgM, IgA, and IgG (T), and a normal concentration of IgG, were present. Results of in vitro testing of the blood lymphocyte blastogenesis showed a weak response to the B-cell mitogen, lipopolysaccharide (LPS), but normal responses to T-cell mitogens. Results of postmortem examination showed synovitis of the left tibiotarsal and both scapulohumeral joints. Atrophy and edema of the lymph nodes and lymphocyte depletion in the thymus and spleen were seen. A subacute inflammatory infiltrate was observed in the kidney, synovium, liver, and brain. Etiologic agents were not identified. This case represents a previously unreported form of immunodeficiency disease in the horse.  相似文献   
72.
Tropical Animal Health and Production - Based on current knowledge, C16 and C18 fatty acids (FA) are considered the most functional FA in hepatic metabolism. Although these FAs have been...  相似文献   
73.
Development plans are mainly responsible for population changes and the conversion of forest and rangelands into agricultural lands and human settlements. Qualitative and quantitative analysis of population and land use changes are necessary to assess the impacts of change on hydrological processes. However, such important issues have been less considered worldwide particularly in developing countries. Therefore, we selected the Shazand Watershed (1740 km2) because of rapid industrialization to track the effects of land use and population changes on streamflow and sediment yield. The data were collected from statistical yearbooks and satellite imageries from 1973 to 2008. All available measurements on discharge and suspended sediment concentration at the Pole doab hydrological station were also collected. The study was conducted for the whole period, as well as the pre‐1991 and post‐1991 as a basis for the economic development growth in the region. We found that the land use and population changes have occurred in the Shazand Watershed, especially in the vicinity of industrial zones. The results showed that the cities, industrial zones, roads, and bare lands quickly increased from 58 · 8 to 134 · 3 km2 during post‐1991. The flow durations, sediment rating curves and trend analyses indicated distinct variations in the relationship between streamflow and sediment and also caused changes within different periods. Based on the results, the mean annual flow and sediment yield in post industrialization (1991–2008) were respectively 0 · 84 and 1 · 19 times of those for pre‐industrialization period and the annual sediment yield increased from 25,000 to 29,850 Mg. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
74.
A pilot-scale system for the intensive land-based culture of abalone was established using an integrated design aimed at eliminating the dependence on external food sources, whilst reducing water requirements and nutrient discharge levels. The system was the first and simplest trial in a series of progressive complexity of the concept of integrated culture of seaweed, abalone, fish and clams in modular and intensive land-based facilities. Relative sizes of the modules, their stocking densities and the rate of nutrient supply were determined based on earlier results to be optimal. Effluents from two abalone (Haliotis tuberculata) culture tanks drained into macroalgae (Ulva lactuca or Gracilaria conferta) culture and biofilter tanks, where nitrogenous waste products contributed to the nutrition of the algae; net algal production from each algal tank was harvested and used to provide a mixed diet for the abalone. Excess algal yield was used elsewhere. The system was monitored to assess productivity and nitrogen partitioning over a year, while improvements were made based on the accumulating results. Total annual N-budgets were combined with mean production figures to determine a suitable ratio of abalone biomass to algal culture vessel productivity, towards commercial application of the concept. The abalone grew on average 0.26% and 0.25% body weight/d in the two culture tanks; reduced growth and increased food conversion ratios (food eaten/biomass gain; w/w) were associated with high summer water temperatures (max. 26.9°C). U. lactuca showed reliable growth and filtration performance (mean production of 230 g fresh weight/m2/d, removing on average 58% of nitrogen supplied). Conversely, G. conferta growth was highly erratic and was deemed unsuitable for the current application. It is estimated that 1 kg of abalone biomass would require food supplied by 0.3 m2 of U. lactuca culture, reducing N inputs required by 20% and N in effluent by 34% when compared to the two organisms grown in monoculture.  相似文献   
75.
免疫接种是控制和根除传染性病原微生物的常用手段之一。在设计有效而经济的免疫程序时,每个鸡场都有其独特的具体情况需要加以考虑。  相似文献   
76.
Chronic inflammation, as reflected by increased level of acute phase protein such as C-reactive Protein (CRP) is highly prevalent in hemodialysis patients. CRP is a strong predictor of overall and cardiovascular mortality and morbidity in hemodialysis patients. This research was conducted to determine the C-reactive Protein (CRP) levels and its correlation to demographic and clinical characteristics and Laboratory values in hemodialysis patients in Sari, Iran. In a cross sectional study, 147 hemodialysis patients were studied. Patients' demographic and clinical data were recorded and also serum CRP, Cholesterol, Albumin, Phosphorous, Calcium, Hemoglobin and Hematocrit levels were measured. Overall, the mean CRP concentration was 15.8 mg L(-1). With considering to the different cutoff point (5, 6.2, 10 mg L(-1)) for CRP level, 107 patients (72.8%) had CRP level >5 mg L(-1), 99 patients (67.3%) had CRP level > 6.2 mg L(-1) and 77 patients (52.4%) had CRP level >10 nmg L(-1). The CRP levels greater than 6.2, had a direct statistically significant correlation with duration of hemodialysis and phosphorus level (p = 0.01). Also, CRP levels above 10 mg L(-1) had a direct statistically significant correlation with age and phosphorus levels (p = 0.02). According to the prevalence of high CRP level and it's correlation with age, duration ofhemodialysis and phosphorus level in hemodialysis patients, CRP level should be screened in this group of patients routinely because of its prognostic importance.  相似文献   
77.
78.
The objectives of this study were to determine the effects of nitrogen (N) forms and deficient and toxic rates of boron (B) on the growth, NO3 accumulation, membrane permeability, mineral nutrition, and nitrogen use efficiency (NUE) of bunch onion (Allium cepa L. var. Radar) plants. Therefore, 20% of NO3 in reference nutrient solution was replaced by NH4, urea, or mixed amino acids (AA). To each of these solutions 3, 30, or 300 mmol m?3 B was added. Fresh and dry weights were the same in the reference and mixed AA treatments, but NH4 and urea decreased these growth parameters as compared to the reference. Mixed AA decreased the NO3-N content while urea increased it, and NH4 treatment yielded similar NO3-N content as compared to the reference. The nitrogen content of plants was increased by NO3 replacement with either NH4 and, urea or mixed AA. At the 300 mmol m?3 B rate, B content of plants was decreased by NH4 and urea, but increased by the mixed AA treatment. Membrane permeability was increased by NH4?replacement of NO3. Nitrogen use efficiency was found the highest in the reference treatment. Nitrogen and NO3-N contents were increased by the 300 mmol m?3 B rate. Increasing B in nutrient solution increased the B contents of plants. Mixed AA treatment decreased the phosphorus (P) content of plants. Potassium (K) and chloride (Cl) contents of plants were decreased in the NH4 treatment where B was applied at the 3 mmol m?3 rate. These results suggest that bunch onion growers may reduce NO3 content in onion tops by partially replacing NO3 with amino acids without reducing yield.  相似文献   
79.
BACKGROUND: Knowing that adenoviral vectors could initiate innate immunity, the ability of E1-deleted recombinant adenovirus (Ad-E1Delta) in induction of B7.1 and IL-2 molecules was studied. METHODS: The expression of green fluorescent protein in C1498 cells following transfection of these cells with adenovirus green fluorescent protein vector confirmed the ability of adenovirus vectors in infecting the cells and inducing the expression of the gene of interest. The expression of B7.1 molecule on the surface of the cells was assayed upon infection with Ad-E1Delta vector. Adenovirus-IL-2/B7.1 vector capable of inducing IL-2 and B7.1 expression in the cells was used as the positive control vector. RESULTS: According to the FACS results, about 4.17% of normal cells expressed B7.1 on their surface, while this level was increased in Ad-E1Delta transduced cells up to 14.43%. These results demonstrate that Ad-E1Delta vector considerably (about 3 folds) increases the expression of B7.1 on the cells. No detectable IL-2 was secreted into the medium of non-transduced and Ad-E1Delta transduced cells. CONCLUSION: Data indicate that the infection of C1498 cells with recombinant adenoviruses stimulates expression of B7.1 on the cell surface rather than secretion of IL-2 into the medium.  相似文献   
80.
This paper presents an innovative process to solve the nitrate build-up problem in recirculating aquaculture systems (RAS). The novel aspects of the process lie in a denitrification bioreactor system that uses solid cotton wool as the primary carbon source and a unique degassing chamber. In the latter, the water is physically stripped of dissolved gaseous O2 (by means of a Venturi vacuum tube), and the subsequent denitrification becomes more efficient due to elimination of the problems of oxygen inhibition of denitrification and aerobic consumption of cotton wool. The cotton wool medium also serves as a physical barrier that traps organic particles, which, in turn, act as an additional carbon source for denitrification. Operation in the proposed system gives an extremely low C/N ratio of 0.82 g of cotton wool/g of nitrate N, which contributes to a significant reduction of biofilter volume. The additional advantage of using solid cotton wool as the carbon source is that it does not release organic residuals into the liquid to be recycled. Operation of the system over a long period consistently produced effluents with low nitrate levels (below 10 mg N/l), and there was only a very small need to replace system water. The overall treatment scheme, also incorporating an aerobic nitrification biofilter and a granular filtration device, produced water of excellent quality, i.e., with near-zero levels of nitrite and ammonia, a sufficiently high pH for aquaculture, and low turbidity. The proposed system thus provides a solution for sustainable small-scale, urban aquaculture operation with a very high recovery of water (over 99%) and minimal waste disposal.  相似文献   
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