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991.
棉花品种抗黄萎病性与体内生化成分相关分析 总被引:12,自引:0,他引:12
对棉花不同抗感黄萎病性品种生化成分分析结果表明:棉花品种在无菌土中体内可溶性还原糖含量相应地高于接菌土中的含量。蕾期抗耐品种平均含量为2.276%,高于感性品种的1.417%,而铃期趋势相反。叶片单宁含量高于根部。在无菌土中,抗耐品种叶片单宁含量平均为3.58%,高于感病品种的3.28%;而在接菌条件下趋势相反。根部棉酚含量显著高于叶部,但两者极显著相关。在无菌土和接菌土中,抗性品种棉酚含量均高于耐性品种,而耐性品种又高于感性品种。棉株体内棉酚含量与棉花品种抗黄萎病性显著正相关。同工酶谱测定显示,过氧化物酶在抗感品种的无病症叶片中,酶带特征基本一致,叶片显症后表现主酶带区加宽,主酶带数增多,变化趋势与症状严重度正相关。在显症条件下,抗性品种酯酶同工酶活性略强于感性品种;与无症叶相比,显症叶的SOD酶带数由原来的4—6条减少至3—4条,抗性品种的酶带数少于感性品种1—2条。 相似文献
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993.
银纹夜蛾人工饲养技术研究 总被引:2,自引:0,他引:2
本文在研究了各种环境因子对银纹夜蛾实验种群影响的基础上,进一步研究了食量,低温保种及饲养管理技术,设计了一种便于收集卵的新型产卵笼,并总结了人工饲养银纹夜蛾的技术要点。 相似文献
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Cryopreservation of gander semen 总被引:2,自引:0,他引:2
1. The effect of dimethylacetamide (DMA) and dimethyl sulphoxide (DMSO) on the cryopreservation of gander semen were investigated. An improved survival rate of spermatozoa after freeze-thawing was obtained when semen was frozen by a fast-freezing procedure on dry ice with 9% DMA as the cryoprotectant. 2. Gander semen, which was frozen during mid season, was tested for fertilising ability in different times of the season. The percentage of fertility during d 3 to d 9 after 2 consecutive inseminations was 68% to 95%, depending on the date of artificial insemination. 相似文献
999.
1. The objective of this trial was to study the effects of chromium nicotinate (Cr) supplementation on the performance, carcase characteristics and blood constituents of 9 to 22 week-old male turkeys. 2. Fifty-four 8-week-old male turkeys weighing 2.9 +/- 0.28 kg were allocated at random into 9 groups with 3 dietary treatments and 3 replicates. The dietary treatment was different dietary concentrations of chromium in the basal diet, to provide 0 (control), 1 or 3 mg/kg. The feeding trial lasted for 14 weeks. 3. Results showed that 1 mg/kg chromium supplementation significantly improved weight gain and food intake at 9 to 18 weeks of age but did not significantly influence performance at 19 to 22 week of age. The breast and thigh muscle were significantly increased in birds receiving 1 mg/kg chromium supplementation but were decreased by 3 mg/kg of supplementation. 4. Dietary chromium supplementation did not significantly influence other serum constituents, including insulin, HDL, VLDL+LDL, HDL-C, VLDL-C+LDL-C, total protein, albumin, and gamma-globulin at 18 and 22 weeks of age. 5. The serum triacylglycerol (TG) and uric acid contents were significantly increased, while glycerol and alpha-globulin were significantly reduced by 3 mg/kg chromium supplementation. However, 1 mg/kg chromium supplementation significantly reduced serum cholesterol and glycerol at 18-weeks old. At 22 weeks of age, 1 mg/kg chromium supplementation significantly increased serum glucose and decreased the uric acid concentration whereas 3 mg/kg chromium supplementation significantly increased the creatinine concentration and decreased beta-globulin concentration. 相似文献
1000.
Kishnani PS Faulkner E VanCamp S Jackson M Brown T Boney A Koeberl D Chen YT 《Veterinary pathology》2001,38(1):83-91
A canine model of glycogen storage disease Ia (GSD Ia), similar clinically, biochemically, and pathologically to the human disease, was established by crossbreeding Maltese and Beagle dogs carrying a mutated, defective glucose-6-phosphatase (G-6-Pase) gene. Ten puppies were born in three litters from these crossbreedings. Six were homozygous for the previously described M121I GSD Ia mutation. Of these six affecteds, two were stillborn, and one died at 2, 32, and 60 days of life, respectively (puppies A, B, C, D, E), while one is alive at age 15 months (puppy F). Affected puppies exhibited tremors, weakness, and neurologic signs when hypoglycemic. They had postnatal growth retardation and progressive hepatomegaly. Biochemical abnormalities included fasting hypoglycemia, hyperlactacidemia, hypercholesterolemia, hypertriglyceridemia, and hyperuricemia. Microscopic examination of tissues from affected puppies showed diffuse, marked hepatocellular vacuolation, with distended clear hepatocytes and central to marginally located rounded nuclei. In the kidneys of puppies D and E, there was segmental glomerular sclerosis and vacuolation of proximal convoluted tubular epithelium. Biochemical analysis revealed increased liver glycogen content and isolated markedly reduced G-6-Pase enzyme activity in liver and kidney. The canine G-6-Pase gene was characterized by screening a canine genomic library. It spans approximately 11.8 kb and consists of five exons with >90% amino acid sequence homology to the derived human sequence. The first 1.5 kb of the 5' region was sequenced and contains several putative response element motifs homologous to the human 5' region. Establishment of this canine colony of GSD Ia that closely resembles human disease and isolation of the canine genomic gene provides an excellent model for studying pathophysiology and long-term complications and an opportunity to develop novel therapeutic approaches such as drug and gene therapy. 相似文献