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951.
笔者用中监所提供的猪丹毒标准株C#-(43)-2,6,7,8和自然野毒株作为菌种,经颈静脉接种100-500亿活菌/头,模拟急性猪丹毒DIC。试验猪34头,发病27头,死亡15头。发病猪生前凝血象出现变化;死后组织学检查,脑、肾、心、肺等器官有DIC形成。电镜观察微血栓为纤维素,红细胞和丹毒杆菌。本文对DIC判定标准,DIC病理组织学特点及其发病机制和意义进行了讨论。  相似文献   
952.
敌百虫对沼泽绿牛蛙蝌蚪的急性毒性试验   总被引:11,自引:0,他引:11  
水温27.5 ̄29℃时,敌百虫对沼泽绿牛蛙蝌蚪24,48,96h的LC50分别为25.70,16.22,7.94mg/L。估算安全质量浓度为0.79mg/L。敌百虫可作为防治牛蛙某些寄生虫病和敌害生物的药物。  相似文献   
953.
甘蓝夜蛾高毒力Bt菌株的筛选   总被引:3,自引:0,他引:3  
东北农业大学昆虫教研室从黑龙江地区病死鳞翅目昆虫体内分离出苏云金杆菌(Bacillusthuringiensis,Bt)菌株74株,随后以甘蓝夜蛾为供试昆虫对这些菌株的毒力进行了测定,结果表明,很多菌株对甘蓝夜蛾的初孵幼虫均具有一定的毒力,经过初筛、复筛,试验选出了毒力相对较高的5个菌株,当菌液浓度在8×10~7个芽孢·mL(-1)时,甘蓝夜饿死亡率分别达到80%~95%,Lc50分别为43,63,68,710,1778倍液。  相似文献   
954.
The effects of repeated oral administration of 2.5–20 mg/kg of two Citrus aurantium fruit extracts standardized to different concentrations of synephrine (4 and 6%, respectively) on food intake, body weight gain, arterial blood pressure, electrocardiogram (ECG) and mortality have been investigated in the rat. C. aurantium administration significantly reduced food intake and body weight gain. However, mortality (not observed in controls) was present in all C. aurantium treated groups. Arterial blood pressure was not modified, but ECG alterations (ventricular arhythmias with enlargement of QRS complex) were evident in animals treated with both extracts. Our data indicate that, in the rat, antiobesity effects of C. aurantium are accompanied by toxic effects probably due to cardiovascular toxicity.  相似文献   
955.
旨在研究氟马西尼联合肾上腺素对钩吻中毒大鼠的解救效果,并验证钩吻可能的毒性作用靶点,为钩吻中毒机制探讨及解救钩吻中毒病例提供参考.构建钩吻大鼠中毒模型,将60只大鼠随机分为4组,分别为对照组、氟马西尼解救组、肾上腺素解救组、联合用药(氟马西尼+肾上腺素)解救组,记录各组大鼠中毒及死亡情况,并监测各组大鼠血压、心率,评价...  相似文献   
956.
香蕉是世界重要的热带亚热带水果,在热带经济的发展中占有重要的地位.我国是世界香蕉重要生产国之一,总产量仅次于印度,位居世界第二.低pH和铝毒是香蕉生产中面临的重要限制因子,严重影响香蕉的产量和品质.明确低pH和铝毒胁迫对香蕉生长和养分吸收的影响,为调控酸性土壤提供重要的理论依据.本研究分别在盆栽和水培条件下开展试验,盆...  相似文献   
957.
仔猪健的急性毒性试验和蓄积性毒性试验结果表明,其LD50为7332mg/kg,蓄积系数为5.26。亚慢性毒性试验结果表明大剂量应用仔猪健对心、肺和脾有损害作用,可显著降低红细胞数、淋巴细胞数、血小板数和血红蛋白含量,具有一定的血细胞毒性作用。试验结果说明仔猪健可在兽医临床安全应用。  相似文献   
958.
Maize cultivars (Zea mays L.) were evaluated for their aluminum (Al) sensitivity using intact plants and excised root tips exposed to 25 μM Al in nutrient solution of low ionic strength and pH 4.3. Aluminum supply increased callose formation and Al concentrations in root tips of intact plants as well as in excised root tips. Using intact plants, differences in Al sensitivity among cultivars could be characterized by Al‐induced callose formation, Al‐induced inhibition of root elongation, as well as Al contents in root tips as parameters. Significant correlations between Al‐induced callose formation and Al contents in root tips (r2 = 0.64**) and inhibition of root elongation (r2 = 0.80***) were found. Excised root tips did not show a significant Al‐induced inhibition of root elongation. While average Al‐induced callose formation was similar for root tips of intact plants and excised root tips, mean Al contents in excised root tips were up to 1.5‐fold higher than in root tips of intact plants after 24 h of Al treatment. Aluminum‐induced callose formation as found in excised root tips did neither correspond to Al‐induced callose formation nor to inhibition of root elongation of intact plants. The addition of 10 mM glucose to the incubation medium led to a significant increase in the elongation of excised root tips and a 2‐3‐fold increase in Al‐induced callose formation. Staining with triphenyl‐tetrazolium‐chloride (TTC) revealed increased viability of these root segments. However, these effects of glucose supply did not improve the characterization of the cultivars for Al resistance. The results presented suggest that Al exclusion mechanisms expressed in root tips of intact plants might be non‐operational in excised root tips. Therefore, the characterization of maize germplasm for Al resistance using excised root tips appears not to be reliable.  相似文献   
959.
The present study aimed to investigate effects of dietary 1,8‐cineole (cineole) on common carp (Cyprinus carpio) health under ammonia toxicity. The fish were fed with four diets supplemented by 0 (control), 0.1 (0.1C), 0.5 (0.5C), and 1 (1C) percent cineole for 2 weeks, before a 24‐hr ammonia exposure. Blood samples were taken before and after ammonia exposure. The results showed that ammonia exposure significantly (p < 0.05) increased serum urea levels, and decreased serum alternative complement (ACH50) activity and serum total immunoglobulin (Ig) levels. Cineole significantly (p < 0.05) increased serum ACH50 activity (0.1% and 0.5% levels) and total Ig levels (0.5% levels). There was no significant difference (p > 0.05) in serum total protein, albumin and globulin levels among the treatments. Before ammonia exposure, there was no significant difference (p > 0.05) in serum alkaline phosphatase (ALP), alanine transaminase (ALT), and lysozyme activities among the cineole treatments. The treatment 0.5C had the lowest lactate dehydrogenase (LDH) and aspartate transaminase (AST) activities before ammonia exposure. After ammonia exposure, serum LDH and ALT activities increased in all treatments, but the treatment 0.5C had the lowest activities. Serum ALP activities increased after the ammonia exposure in the control and 1C groups. Serum AST and lysozyme activities increased after the challenge in all groups except for the 0.5C group. Overall, the results suggest that ammonia exposure causes increase in serum LDH, ALP, AST, and ALT activities and decreased immune responses, which are indicator of tissue damage and immunosuppression. 0.5% cineole is capable to suppress adverse effects of ammonia intoxication in carp.  相似文献   
960.
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