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排序方式: 共有771条查询结果,搜索用时 15 毫秒
181.
Effect of clinoptilolite on serum biochemical and haematological characters of broiler chickens during aflatoxicosis 总被引:4,自引:0,他引:4
Clinoptilolite (CLI, a natural zeolite) incorporated into the diet at 1.5 and 2.5 per cent were evaluated for their ability to reduce the deleterious effects of 2.5 mg total aflatoxin (AF) kg(-1)diet on broiler chickens from 1 to 21 days of age. In total 360 broiler chicks were divided into six equal treatment groups (control, AF, CLI (1.5 per cent), AF plus CLI (1.5 per cent), CLI (2.5 per cent) and AF plus CLI (2.5 per cent)). When compared with the controls, AF treatment significantly decreased serum total protein, albumin, inorganic phosphorus, uric acid, total cholesterol and the values of haematocrit, red blood cell counts, mean corpuscular volume, haemoglobin, thrombocyte counts, percentage of monocyte counts; increased values of white blood cell and heterophil counts. The addition of CLI (1.5 per cent) and CLI (2.5 per cent) to the AF -containing diet reduced the adverse effects of AF and should be helpful in a solution to the aflatoxicosis problem in poultry. 相似文献
182.
Mustafa Cemek Mehmet Emin Büyükokuro?lu Fatih Aymelek 《Pesticide biochemistry and physiology》2010,98(1):9-18
The present study was designed to investigate the effects of vitamin E (vit E), selenium (Se) and vit E + Se against organophosphate (OP) toxicity in tissues’ trace and major element levels and erythrocyte antioxidant enzyme activities of rats. Trace and major element concentrations in the tissues were measured by inductively coupled plasma-optical emission spectroscopy. Erythrocyte antioxidant enzyme activities were studied by using spectrophotometer. Antioxidant enzyme activities such as superoxide dismutase, glutathione peroxidase and catalase increased in the fenthion-treated groups (control) more than that of sham group subjects. Heart and pectoral muscle tissue Se and Zn concentrations in the control group were higher than sham group. However, jejunum, kidney, liver and pancreas Se and Zn concentrations in the control group were found to be lower than those in the sham group. The Mn concentrations in the all of the tissues were lower in the control group when compared with the sham group. Brain, heart, jejunum, kidney and pancreas Fe concentrations and heart, jejunum, liver, pectoral muscle and pancreas Cu concentrations were found to be lower in the control group. The treatment of vit E, Se and vit E + Se were increased bio-element levels in the many tissue. In conclusion, the results of the present study demonstrate that the tissue trace and major element concentrations and enzymatic antioxidant system were significantly affected OP toxicity. Furthermore, we have shown an association between bio-elements and antioxidant enzymes in OP toxicity. In addition, administration of vit E, Se and vit E + Se might regulate some trace and major element levels in the many tissues. 相似文献
183.
2011年6月调查了渭河流域陕西段4座水库的浮游生物种群结构,并根据浮游生物生物量对4座水库的营养类型进行了划分.结果表明,4座水库浮游植物共计8门、40种(属),细胞密度为12.00×104~ 132.50×104个/L,浮游植物生物量为0.3944~ 2.7670 mg/L;浮游动物分为4大类、26种,种群密度为20 ~2 150个/L,生物量为0.0010 ~1.8520 mg/L,各水库浮游生物种群密度和生物量的大小顺序为西郊水库>桃曲坡水库>西骆峪水库>石头河水库.根据有关营养类型划分标准,4座水库中,西郊水库和桃曲坡水库为中营养水库,石头河水库和西骆峪水库为贫营养水库,并对各水库浮游生物的种群结构与营养类型之间的响应关系以及营养类型的成因进行了讨论和分析. 相似文献
184.
阿克苏河中游荒漠河岸林物种多样性与群落稳定性 总被引:1,自引:0,他引:1
[目的]探究阿克苏河中游荒漠河岸林群落的物种多样性、稳定性及其之间的关系,在物种水平上对当前群落植物组成的复杂性及部分环境因子的关系进行探讨,为荒漠河岸生态系统的恢复提供理论依据。[方法]在样方调查的基础上,运用格局分析法,物种多样性指数与均匀度指数,聚类分析以及M.Godron稳定性测度对植物群落进行综合评估。[结果]阿克苏河中游荒漠河岸林主要的植物种群均呈现聚集分布的格局,群落结构简单,具有单寡种优势群落的特征。不同地段的植物群落物种分布较为均匀,但丰富度与多样性的高低略有起伏;荒漠河岸林植物群落根据环境因子的聚类结果可分为6个群丛,其中有3个群丛的物种多样性较低。物种组成与土壤水分的关联较为密切;当前植物群落尚未达到稳定阶段,物种多样性与群落稳定性者之间并无任何直接联系。[结论]单一以河水漫灌的方式促进该地区植物多样性的恢复具有一定的困难,考虑以胡杨、柽柳为主要格局,种植深根系的乔灌木以营造局部地区小气候,间接优化生境的方式对荒漠河岸林的植被恢复更为有利。 相似文献
185.
Celik I Oğuz H Demet O Boydak M Dönmez HH Sur E Nizamlioğlu F 《British poultry science》2000,41(4):401-409
1. The embryotoxicity of mixed aflatoxins (AF) and aflatoxin B1 (AFB1) were evaluated by a modified chick embryotoxicity screening test (CHEST). Adverse effects on the early embryonic development of thymus and bursa of Fabricius were also investigated by light microscopy. AF consisted of 83.06% AFB1, 12.98% AFB2, 2.84% AFG1 and 1.12% AFG2. 2. A total of 448 fertilised laying hens' eggs were used. AF and AFB1 were injected into the eggs at doses of 10, 100 and 1000 ng/egg. Embryonic developmental stages were evaluated according to the Hamburger-Hamilton scale (HH-scale). 3. The results showed that AFB1 given at 10 ng/egg had a significantly (P<0.05) greater embryotoxic effect than AF given at a similar dose. The higher doses of both AF and AFB1 caused higher embryonic mortality and also an increase in early deaths. 4. In the groups receiving 100 ng/egg AF and AFB1 an abnormal development was seen, with a protruded central region, corresponding to the area pellucida of the blastoderm. No other developmental abnormality attributable to AF or AFB1 was found. 相似文献
186.
187.
Orhan Tokmakoğlu 《Journal of pest science》1965,38(2):23-25
Zusammenfassung 1. Es gelang die vollständige kontinuierliche Zucht vonS. luniger unter hier näher beschriebenen Bedingungen.2. Die Kopulation erfolgte nur im Fluge, frühestens 4 Tage nach dem Schlüpfen, bei relativer Luftfeuchtigkeit von 65–70%.3. Die Larvenentwicklung dauerte bei 22°C 8 bis 10 Tage. Die Mortalität erreichte 40–45%. Zur Verpuppung bevorzugten die Larven lockere, feuchte Medien.4. Die Puppen entwickelten sich am schnellsten bei 22–25°C, einem Temperaturbereich, in dem auch die geringste Mortalität auftrat. Es bestehen Anhaltspunkte dafür, daß die Mortalität bei langsamer Entwicklung höher ist als bei schneller.Herrn Professor Dr. F. Schwerdtfeger zum 60. Geburtstag gewidmet. 相似文献
188.
Leaf beetle occurrence and abundance on certain shrubs and bushes were surveyed during 2002–2003 in several natural habitats of Isparta. The 34 leaf-beetle species collected are listed and classified according to their relative percentage of the total caught and to their associated host plants. In all habitats sampled, leaf beetles showed a preference for plants from the genera Quercus and Crataegus. Some abundant species causing serious damage to their food plants are discussed. 相似文献
189.
190.
The electric-arc technique used to generate single-walled carbon nanotubes (SWCNTs) is introduced. Especially, the superconductivity of SWCNTS is concerned. The samples of single-walled carbon nanotubes are suspended between two superconducting electrodes and their super-currents may be observed under special conditions. It is called 'proximity-induced method'. With the method, some experiments show that SWCNTs have higher critic super-currents, and the temperature and magnetic field dependence of the critic currents exhibits unusual features. 相似文献