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Tropical Animal Health and Production - This research was conducted to determine the prevalence and intensity of infection with nymphs of Linguatula serrata in mesenteric lymph nodes of the goats...  相似文献   
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Different factors affect zinc (Zn) nutrition of plants, among which pH and phosphorus (P) have been studied widely but nitrogen (N) has not received much attention. The present experiment was designed to study the effect of N and P on growth and Zn nutrition of corn (Zea mays L.) in a highly calcareous soil of Iran. The experiment was a 3x3x2 factorial in randomized complete blocks with three replications which was conducted in greenhouse for eight weeks. Treatments consisted of three levels of N (0,75, and 150 mg/kg), three levels of P (0, 50, and 100 mg/kg), and two levels of Zn (0 and 20 mg/kg). Application of N increased dry matter (DM), N concentration and uptake, Zn concentration and uptake, and N: P and N: Zn ratios of plant tops; but it decreased P concentration and uptake and P: Zn ratio. Application of P increased DM, P concentration and uptake, N uptake, and P: Zn and N: Zn ratios; but it decreased N and Zn concentrations and N: P ratio. Dry matter and Zn concentration and uptake increased but P: Zn and N: Zn ratios decreased following the application of Zn. Multiple regression equations obtained showed the influence of N application on increasing Zn concentration and uptake and lowering the P: Zn ratio of plant tops. It was concluded that N application improves Zn nutrition of corn in highly calcareous soils by increasing plant Zn concentration and uptake and decreasing P concentration. This lowers the P: Zn ratio of plant tops to a more optimum range for plant growth.  相似文献   
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Heavy metal uptake, translocation and partitioning differ greatly among plant cultivars and plant parts. A pot experiment was conducted to determine the effect of cadmium (Cd) levels (0, 45 and 90 mg kg?1 soil) on dry matter yield, and concentration, uptake and translocation of Cd, Fe, Zn, Mn and Cu in seven rice cultivars. Application of 45 mg Cd kg?1 soil decreased root and shoot dry weight. On average, shoot and root Cd concentrations and uptake increased in all cultivars, but micronutrients uptake decreased following the application of 45 mg Cd kg?1. No significant differences were observed between 45 and 90 mg kg?1 Cd levels. On average, Cd treatments resulted in a decrease in Zn, Fe and Mn concentrations in shoots and Zn, Cu and Mn concentrations in roots. Differences were observed in Cd and micronutrient concentrations and uptake among rice cultivars. Translocation factor, defined as the shoot/root concentration ratio indicated that Cu and Fe contents in roots were higher than in shoots. The Mn concentration was much higher in shoots. Zinc concentrations were almost similar in the two organs of rice at 0 and 45 mg Cd kg?1. A higher Cd level, however, led to a decrease in the Zn concentration in shoots.  相似文献   
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Preeclampsia is a disease regarding with altered vascular reactivity leading to hypertension of the mother and metabolic alterations in the fetus. This study aimed to assess nitric oxide and bleeding time following administration of magnesium sulfate to preeclamtic patients compared to normotensive pregnant women. A total of 112 subjects (56 preeclamtic patients and 56 normotensive pregnant controls) were enrolled in this case-control study. Cases and controls were matched for age, BMI, gestational age, parity and gravidity. Total concentration of nitrite and nitrate (NOx) was measured before and during magnesium sulfate (MgSO4) treatment using a modified Griess-based method. RESULTS: Systolic and diastolic blood pressures were significantly decreased during MgSO4 treatment in preeclamtic patients (p < 0.0001). NOx levels were significantly increased in preeclamtic women after MgSO4 administration (33.7 +/- 18.5 vs. 50.2 +/- 21.6, p < 0.0001) but it was not seen in normotensive parturients (52.4 +/- 28.9 vs. 57.3 +/- 21.7, p = 0.362). The bleeding time was scarcely increased following magnesium sulfate treatment in preeclamptic patients compared to normotensive pregnant women but it was not significant (p = 0.18). In addition, there was only a significantly reverse correlation between NOx levels and systolic or diastolic blood pressure in preeclamtic parturients after MgSO4 treatment (r = -0384; p = 0.003 and r = -0.29; p = 0.03, respectively). This study demonstrates that administrating MgSO4 to preeclamtic patients induced significant changes in NOx production which had a major role in modulating vasculature changes in preeclamsia.  相似文献   
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Eurasian Soil Science - The major goal of this research was to assess the ability of visible-near-infrared (VIS-NIR) spectroscopy combined with multivariate regressions based on four modeling...  相似文献   
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ABSTRACT

A pot experiment was conducted in a greenhouse on a calcareous soil (fine, mixed, mesic, Fluventic Haploxerepts) to study the interaction of zinc (Zn) and boron (B) on the growth and nutrient concentration of corn (Zea mays L.). Treatments consisted of a factorial arrangement of seven levels of B (0, 2.5, 5, 10, 20, 40, and 80 mg kg? 1as boric acid), two sources of Zn [zinc sulfate (ZnSO4 · 7H2O) and zinc oxide (ZnO)], and three levels of Zn (0, 5, and 10 mg kg? 1) in a completely randomized design with three replications. Plants were grown for 70 d in 1.6 L plastic containers. Applied Zn significantly increased plant height and dry matter yield (DMY) of corn. Source of Zn did not significantly affect growth or nutrient concentration. High levels of B decreased plant height and DMY. There was a significant B × Zn interaction on plant growth and tissue nutrient concentration which were rate dependent. In general, the effect of B × Zn interaction was antagonistic on nutrient concentration and synergistic on growth. It is recommended that the plants be supplied with adequate Zn when corn is grown in high B soils, especially when availability of Zn is low.  相似文献   
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Pot experiment was conducted in a greenhouse to compare the effect of four organic substrates [S1: Persian turpentine trees leaf mold (50%) + Soil (50%); S2: Oak leaf mold (50%) + Soil (50%); S3: Cypress leaf mold (50%) + Soil (50%) and S4: liquorice processing wastes (50%) + Soil (50%)] application on strawberry growth, yield, and nutrient concentration, and on some soil properties. Results showed that leaves mold and liquorice wastes application decreased pH, increased soil organic matter, and increased soil concentrations in all mineral elements studied, except for potassium (K). The amount of mineral elements in substrates had also a great influence on the leaf nutrient concentrations. High levels of nitrogen (N), K, iron (Fe), manganese (Mn), and zinc (Zn) were obtained in leaves; while phosphorus (P) concentration was lower than sufficient levels. Although, strawberry fresh and dry weights and leaf chlorophyll content were significantly higher in plants grown in S4 with no added fertilizer, the highest fruit yield was obtained in combination substrates with 50% fertilizer. Our results indicate that use of leaf mold and liquorice wastes in soil mixtures can reduce the amount of fertilizer required for optimum strawberry plant growth and yield.  相似文献   
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The objective of the investigation was to evaluate the effect of applied phosphorus (P) and cadmium (Cd) on Cd chemical forms determined by sequential extraction and the relationship between these forms and plant responses, i.e., dry weights, concentration, and total uptake of Cd and P in a greenhouse experiment. Treatments consisted of five levels of Cd (5, 10, 20, 40 and 80 mg kg?1 soil as cadmium sulfate) and four levels of P (0, 15, 30 and 60 mg kg?1 soil as monocalcium phosphate), which were added to the soil and left to equilibrate for 1 month under greenhouse conditions. Spinach seeds (Spinacea oleracea L., cv Viroflay) were sown and then grown for 8 weeks. The chemical composition in the aerial part of the pant and soil was determined. Application of Cd decreased plant dry matter and increased Cd concentration in the plant, whereas at each level of applied Cd, P increased plant dry matter and decreased plant Cd concentration. All chemical forms of Cd in soil, as determined by a fractionation method, were increased following Cd application, the highest being the carbonatic form. Phosphorous application decreased exchangeable and carbonatic forms of Cd, whereas it increased other forms.  相似文献   
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