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51.
Field experiments were conducted at Tamil Nadu Rice Research Institute, Aduthurai, India, during the wet seasons of 1992 and 1993 to study the effect of full and partial substitution of fertiliser N with green manure N (Sesbania rostrata) on nitrogen uptake, yield attributes and yield of rice. The experiment consisted of eight treatments with two levels of N (100 and 200 kg ha−1 ) and three sources of N application viz., fertilizer, integrated (1:1 fertilizer and green manure N) and green manure N compared to the recommended practice (150 kg fertilizer plus 6.25 t ha−1 (72 kg N) green manure) and a no N control. Nitrogen application markedly increased the N uptake. Combined use of the two N sources at 200 and 222 kg N ha−1 and of single fertilizer N at 200 kg N ha−1 recorded the maximum N uptake, increased the yield attributes such as number of panicles per unit area, weight per panicle, number of total and filled grains per panicle and test weight. At 200 kg N ha−1 full substitution of N by green manure reduced the grain yield but only partial substitution of N by green manure resulted in almost similar yield as single fertilizer N. Thus 200 kg N ha−1 applied in equal proportions of fertilizer and green manure N can be recommended for medium duration rice cultivars. 相似文献
52.
过氧化物酶体增殖剂受体与脂质代谢调控 总被引:5,自引:0,他引:5
综述了过氧化物酶体增殖剂受体在动物体内的分布、结构与转录调节机制及其对脂肪细胞分化、脂质代谢的调控。 相似文献
53.
The use of cultured hepatocytes from goats and cattle to investigate xenobiotic oxidative metabolism
C. Montesissa P. Anfossi G. Van't Klooster M. Mengelers 《Veterinary research communications》1996,20(5):449-460
The oxidative metabolism of aldicarb (ALD), a carbamate pesticide, and fenbendazole (FBZ), an anthelmintic, was studied using cultured hepatocytes obtained from 4 goats and a bullock and incubated with ALD (50 mol/L) and FBZ (10 mol/L). The parent compounds and the metabolites were measured by HPLC. Both compounds are metabolized at the sulphur atom via two sequential oxidations, first to the sulphoxide (aldicarb sulphoxide and oxfendazole, respectively) and then to the sulphone. Oxfendazole and fenbendazole sulphone from FBZ, and aldicarb sulphoxide from ALD were found in both species. Aldicarb sulphone was not produced by the hepatocyte preparations from the bullock. The good correlation obtained comparing the in vitro results of FBZ metabolism with published in vivo dat obtained on FBZ kinetics in the same species confirmed the usefulness of in vitro models for predictive analysis of in vivo xenobiotic biotransformations.Abbreviations ALD
aldicarb
- ALDSON
aldicarb sulphone
- ALDSOX
aldicarb sulphoxide
- BSA
bovine serum albumin
- ID
internal diameter
- EGTA
ethylene glycol bis(-aminoethyl ether) N,N,N,N-tetraacetic acid
- FBZ
fenbendazole
- FBZSON
fenbendazole sulphone
- HBSS
Hanks' balanced saline solution
- HPLC
high-pressure liquid chromatography
- LDH
lactate dehydrogenase
- MFO
mixed function oxidase
- NCS
newborn calf serum
- OXF
oxfendazole
- WME
Williams' Medium E 相似文献
54.
G. Tuitert Y. Hofmeester 《European journal of plant pathology / European Foundation for Plant Pathology》1994,100(1):19-53
A field experiment was set up in 1988 to study the development of rhizomania disease of sugar beet at different inoculum levels of beet necrotic yellow vein virus (BNYVV) in soil. Five, tenfold different, inoculum levels were created by addition of the approximate amounts of 0, 0.5, 5, 50 and 500 kg infested soil per ha (the latter corresponding to 0.01% v/v calculated to the tillage layer). A drip irrigation treatment was applied to study the influence of soil moisture on disease. Susceptible sugar beet, cv. Regina, was grown for three consecutive years.In the first year, root symptoms were not observed, but BNYVV-infected plants were detected by ELISA in low numbers at all inoculum levels at harvest. After late drilling in 1989, high numbers of infected plants, up to 90–100% in plots with the highest inoculum level, were detected already in June. Root symptoms were also observed from June onwards. In both these years disease incidence increased in time and was significantly influenced by the initial inoculum level. In the third year, the whole field was heavily diseased, and only for the non-irrigated plots incidence differed for different initial inoculum levels. The expression of symptoms by BNYVV-infected plants was influenced by initial inoculum level, thus by the amount and timing of primary infection.Root weight at harvest was not affected, but sugar content decreased with increasing inoculum level already in 1988, leading to a reduction in sugar yield of 10% at the highest inoculum level. In 1989, both root weight and sugar content decreased progressively with increasing inoculum level, resulting in sugar yield reductions of 11–66% (down to approximately 3000 kg ha–1) for low to high inoculum levels compared to the control. As the control plots became contaminated, all yields were low in 1990, still showing a decrease with increasing inoculum level in the non-irrigated plots, but an overall mean sugar yield of 3323 kg ha–1 for the irrigated ones.Sodium and -amino nitrogen content of the root, additional quality parameters determining extractability of sucrose, showed an increase and decrease, respectively, with increasing initial inoculum level already in the first year. The relative differences in contents compared to those from the control were largest for Na content. A significant negative correlation was found between Na (mmol kg–1 root) and sugar content (% of fresh weight); linear for 1988, exponential for 1989 and 1990.In spring 1989, the infestation of individual plots was assessed using a quantitative bioassay estimating most probable numbers (MPNs) of infective units of BNYVV per 100 g dry soil. The relationship between the MPns determined and root weight, sugar content and sugar yield at harvest could be described by Gompertz curves. The increase in disease incidence with increasing MPN in 1989 was adequately fitted with a logistic equation. 相似文献
55.
Hill D Correa MT Stevens JB 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1994,23(3):73-75
Azostix-reagent-tests(R) strips (Ames, Miles, Inc., Diagnostic Division, Elkhart, IN) were used to measure blood urea nitrogen values in blood samples from 125 dogs and cats at the North Carolina State University, College of Veterinary Medicine. Results of the tests were compared with standard serum urea nitrogen results. Sensitivity, specificity, and negative predictive values were high (86.4, 90.3, and 96.5%, respectively). Positive predictive value was low, 65.5% of the dogs and cats with elevated blood urea nitrogen values were correctly classified as abnormal The test performs well when the prevalence of abnormal values is near 50%. 相似文献
56.
C. Jacyn Baker Daniel P. Roberts Norton M. Mock Bruce D. Whitaker Kenneth L. Deahl Andrey A. Averyanov 《Physiological and Molecular Plant Pathology》2005,67(6):1322
The plant apoplast is an important mediator of communication between the cell cytoplasm and its surroundings. Plant cell suspensions offer a convenient model system to gain insight into apoplastic physiology. Here, we describe a novel phenomenon that took place when two naturally occurring phenolics were added together to either soybean or tobacco cell suspensions. Acetosyringone (AS) and/or hydroxyacetophenone (HAP), phenolics found in the extracellular/apoplast of tobacco cells, were added to soybean or tobacco cell suspensions undergoing an oxidative burst. Individually, AS appeared to be utilized as a typical peroxidase substrate to scavenge hydrogen peroxide, while HAP was utilized at a much lower rate. However, when added together the rate of utilization of both phenolics increased and surprisingly resulted in the production of hydrogen peroxide. We have further characterized this novel phenomenon in suspension cells. This study demonstrates that certain phenolics in plants can cause co-oxidation which, as in animals, could alter the structure and bioactivity of surrounding phenolics. 相似文献
57.
饲粮中添加抗菌肽对肉鸭增重及血清尿素氮、总蛋白水平的影响 总被引:12,自引:1,他引:12
240只1日龄肉鸭随机成分4组,每组设3个重复,对照组用基础日粮,试验组在基础日粮上每千克分别添加1、2、3mL抗菌肽制剂。结果显示:1)2、3mL/kg添加量组增重效果显著(P<0.05),3mL/kg添加量组最佳;净肉率升高,达到显著水平(P<0.05),其中主要是胸肌率上升;腹脂率降低但差异不显著(P>0.05);料重比无显著变化(P>0.05)。2)血清总蛋白浓度差异不显著(P>0.05),但尿素氮浓度下降,2、3mL/kg添加量组达显著水平(P<0.05),3mL/kg添加量组最低。 相似文献
58.
59.
60.
选择3周龄健康、无病、体重无显著差异的肉仔鸡96只,随机分为3组,每组设4 个重复,每个重复8只。分别饲喂蛋白质水平(19.5%)相同而能量水平不同(3.0 Mcal/kg、 3.08 Mcal/kg、3.16Mcal/kg)的3种饲粮。试验结果表明:前两周饲料转化(采食/增重)均以 中能量组(3.08 Mcal/kg)最好,为1.4416±0.1199,但三种不同能量水平对肉仔鸡平均日增 重、平均日耗料、饲料转化率均差异不显著(P>0.05);后两周饲料转化仍以中能量组最好,为 1.6362±0.1346,且显著优于高能量组(P<0.05),而与低能组和中能组之间差异不显著,各 能量处理组蛋白质、粗纤维、钙的代谢率均差异不显著(P>0.05),而磷的代谢率却存在显著 差异(P<0.05),其中,以中等能量组的磷代谢率最高,平均为90.73%;3种能量水平下肉仔鸡 半净膛率、全净膛率均差异不显著(P>0.05),表明能量水平并不影响肉仔鸡屠宰性能。 相似文献