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111.
To evaluate the magnitude of copper deficiency in Northern India and to examine the various haematobiochemicals, enzymes, vitamins and immune functions affected by copper deficiency, and to identify the parameters which can be of diagnostic importance in copper deficiency, a survey was conducted in 12 districts of Northern India. Significant deficiency of copper was observed in soil, fodder and serum samples of buffalo heifers. Fifty hypocuperaemic buffalo heifers were selected from these areas and were randomly divided into two groups, A and B. The heifers in group A were provided with mineral mixture containing copper sulphate and in group B without copper sulphate. Significant (p < 0.01) improvement in serum ceruloplasmin level was observed within 30 days of treatment, while significant (p < 0.01) improvement in monoamine oxidase and liver cytochrome oxidase was observed at the 60th day of treatment in group A animals. Significant improvement was observed in T3 and T4, in the animals of group A within 60 days of treatment. The values of vitamin A and E showed significant (p < 0.01) improvement within 30 days of treatment. The phagocytic activity of neutrophils against Candida albicans significantly (p < 0.01) improved in group A within 60 days of treatment. Similarly, significant improvement in superoxide dismutase activity in red blood cells was observed at the 30th day, and in total leukocytes and whole blood at the 60th day in group A animals. Significant improvement in liver copper level was observed at the 30th day of treatment, while in group B the liver copper was significantly (p < 0.01) depleted at the 60th day of experimentation. Additional copper supplementation improved growth performance significantly in group A.  相似文献   
112.
The objective of the present study was to examine the effects of parenteral administration of iron and copper on hematological parameters, weight gain, and health of neonatal dairy calves in the period when iron and copper deficiency could be existed. Twenty-four Holstein calves were used for the experiment and randomly assigned to four different treatments. Treatments consisted of (1) control (no injections of Fe and Cu), (2) test 1 (1000 mg Fe as fe-dextran was injected to each calf at day 2 of age), (3) test 2 (160 mg Cu as methionine-copper complex was injected to each calf at day 14 of age), and (4) test 3 (Fe and Cu were injected to each calf as mentioned previously). Blood samples were collected from all of the calves within 24-48 hours after birth and at 7, 14, 21 and 28 days of age for measuring hematological parameters and within 24-48 hours after birth and at 14, 21 and 28 days of age for the determination of iron, copper, TIBC concentrations, and AST activity. Anti-coagulated blood was analyzed shortly after collection for: number of red blood cell (RBC), hemoglobin (Hb), heamatocrit (HCT), total leukocyte count (WBC), Platelet (Plt), MCH, MCV, MCHC, and differential leukocyte counts. The amounts of iron, copper, TIBC, and AST were measured in serum. Group had significant effects on the amounts of HCT, RBC, hemoglobin, MCV, neutrophil, weekly weight gain, and daily gain during each week (p < 0.05). Sampling time had significant effects on the amounts of RBC, MCV, MCH, MCHC, WBC, neutrophil, lymphocyte, monocyte, platelet, fibrinogen, copper, TIBC, AST, weight, weekly gain and, daily gain during each week (p < 0.05). significant interactions between sampling time and group were seen for HCT, RBC, hemoglobin, MCV, platelet, total protein, fibrinogen, iron, and TIBC (p < 0.05). Improved RBC parameters and MCV were seen in calves of group 4 (test 3) in comparing with control group. Total and daily gains were also significantly improved in test groups in comparing with control group (p < 0.05). No significant difference was seen for the days of treatment between groups.  相似文献   
113.
Status of certain oxidative stress indices and zinc and copper concentrations in blood were estimated in dogs with localized demodicosis (LD) and generalized demodicosis (GD). In comparison to healthy control, erythrocytic lipid peroxides level and superoxide dismutase activity were significantly (P < 0.01) higher in both LD as well as GD. However, level of reduced glutathione and activity of catalase were significantly (P < 0.01) lower in both LD and GD. Blood zinc and copper levels in dogs with LD and GD were significantly (P < 0.01) lower than healthy control. Significant (P < 0.01) differences were also observed in different oxidative stress indices and zinc and copper levels in between LD and GD groups. From the present study, it was concluded that demodicosis is associated with oxidative stress and antioxidant supplementation may be beneficial in management of canine demodicosis.  相似文献   
114.
伴随高等教育大众化进程及教学改革的深入,学生评教工作开始在国内推广。为保障学生评教工作的有效实施,我国学者对此做了大量的研究。通过对1991年 ̄2010年国内研究文献的梳理,发现国内学者对评教价值、评教权的定位、效度与信度及影响因素等给予了高度的关注,并就学生评教提出了各自的改进意见。  相似文献   
115.
龙须菜对水体Cu2+、Cd2+的去除效率及其生理响应   总被引:1,自引:0,他引:1  
通过室内实验,研究了龙须菜对水体Cu^2+、Cd^2+的去除效率及其部分生理生化指标的变化状况。结果显示,龙须菜对水体低浓度(0.05mg/L)Cu^2+、Cd^2+的去除率分别达到了99.9%和93.1%;对较高浓度(0.5mg/L)Cu^2+、Cd^2+的去除率分别为55.24%和86.15%;水体较高浓度(0.5mg/L)Cu^2+会导致龙须菜叶绿素a、b和藻红素的含量均显著下降(P〈0.05),而高浓度(2.5mg/L)Cd^2+不会导致色素含量的显著下降;龙须菜对环境中Cu^2+的生理响应浓度也明显小于Cd^2+,藻体SOD活性出现峰值且MDA含量显著高于(P〈0.05)对照组的浓度水平分别为Cu^2+0.05mg/L及Cd^2+0.5mg/L。龙须菜更适宜作为对海水Cd^2+污染进行生物修复的植物。  相似文献   
116.
砂质土壤上造林会引起土壤酸化,影响铜和锌的释放。本文用模拟方法研究了砂质耕地造林引起土壤酸化对土壤中铜和锌释放的影响。结果表明,酸化可明显改变土壤中铜和锌的化学形态,促使碳酸盐结合态铜和锌向交换态、有机质结合态和氧化物结合态形式转化,增加土壤铜锌的释放和淋出潜力,其中对锌的影响尤为明显。铜和锌溶解度明显增加的土壤 pH 分别为 3.8-4.5和 6.2-6.5。图3表2参14。  相似文献   
117.
徐莹梅  田胜尼  周疆丽 《安徽农业科学》2012,40(4):2225-2227,2277
对安庆月山铜尾矿废弃地定居的旱柳群落结构进行了野外调查和分析。调查发现,该调查区域内自然定居的高等植物24种,隶属于13科24属。木本植物中以旱柳为主,草本植物中以白茅、芦苇和水蜡烛为主;群落中木本植物中旱柳的重要值为2.34,远高于其他定居的木本植物,其为铜尾矿木本植物群落的建群种和优势种,该群落为旱柳群落。该群落的多样性较低,其Simpson指数为0.615 3,Shannon-Wiener指数为2.557 0,均匀度E为0.193 6。结果表明,铜尾矿废弃地定居的旱柳群落结构简单,群落多样性指数低,属于草本植物群落向木本植物群落演替的初期阶段。  相似文献   
118.
铜对华北落叶松体内多酚氧化酶的影响   总被引:2,自引:0,他引:2  
对20多年生华北落叶松林及三年生换床苗铜元素及多酚氧化酶在体内的变化规律以及同工酶进行了研究,结果表明:(1)同器官中PPO酶的含量和活力差异极为显著,同一器官不同时间的多酚氧化酶的含量和活力差异也极为明显,多酚氧化酶是华北落叶松的抗寒性基础条件之一。(2)PPO酶活性的变化与Cu含量变化有关,铜处理处理后PPO酶活性增加。(3)铜处理华北落叶松能合成新的PPO同工酶蛋白,可以增加原有同工酶的活性。  相似文献   
119.
通过水培试验研究了重金属铜对青菜幼苗生长的影响。结果表明:低浓度铜离子就能够明显抑制青菜根系的伸长,1μmol/L Cu2 处理,根系伸长量为对照的71.64%;3μmol/L Cu2 处理,根系伸长量下降为对照的26.12%。不同浓度的Cu2 处理能降低青菜幼苗地上部的生物量,但在低浓度的Cu2 (≤5μmol/L)处理下,青菜根系生物量却有上升的趋势。5μmol/L Cu2 处理,青菜幼苗叶片的叶绿素a、b的含量明显降低;与对照相比10μmol/L Cu2 处理,叶绿素a、b的含量分别减少了45.24%和50.69%。  相似文献   
120.
热空气干燥法对ACQ-D在木材内固着的加速作用   总被引:1,自引:0,他引:1  
为了弄清楚热空气干燥法对加速ACQ-D(胺溶季铵铜D型)在木材内固着的加速作用,该研究采用浓度为1%的ACQ-D溶液对杉木试材进行真空浸注处理,在室温下预固着48 h后,分别对试材进行了不同的后处理,其中包括气干不包膜、气干包膜、热空气干燥不包膜、热空气干燥包膜.热空气干燥的温度为50℃,处理时间分别为2、6、12和24 h;气干处理的时间分别为1、2、4和8 d.后处理结束后进行抗流失性试验,然后测定试材中残留的铜含量,在此基础上计算ACQ-D处理杉木中铜的流失率.研究结果表明:①气干处理和热空气干燥处理对ACQ-D防腐剂在木材中的固着都有一定的积极作用,而且随着处理时间的增加固着效果都有所提高;②热空气干燥处理在固着方面的作用要优于气干处理,所需时间短而且固着效果好,在本试验条件下处理6 h以上抗流失效果较好;③包膜与不包膜两种方法应用于气干处理和热空气干燥处理中的效果有所不同,气干包膜的抗流失效果比气干不包膜的要好,而热空气包膜却比热空气不包膜的要差很多,这可能是因为使用的塑料薄膜阻碍了热量传导,使木材内的温度偏低,不利于铜在木材中的固着.   相似文献   
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