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71.
Walter GL McGraw P Tvedten HW 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1992,21(1):23-27
An enzymatic, kinetic method for determining serum lipase activity was evaluated and compared to a standard manual method for use in dogs. The kinetic method was a commercial kit adapted for use on a tandem access clinical chemistry analyzer and utilized a series of coupled enzymatic reactions based on the hydrolysis of 1,2-diglyceride by lipase. The manual method was the Cherry-Crandall technique based on the titration of base against the acid formed by hydrolysis of an olive oil substrate by lipase. The correlation between the two methods was very good (r = 0.94). The reference range for 56 clinically healthy dogs assayed by the kinetic method was 90 to 527 U/L. Diseases associated with a greater than twofold elevation in serum lipase activity as determined by the kinetic method included pancreatitis, gastritis with liver disease, and oliguric renal failure with metabolic acidosis. In some cases, pancreatitis was seen with other clinical problems, such as gastroenteritis, diabetic ketoacidosis, duodenal mass, disseminated intravascular coagulation, and septic peritonitis. Diseases associated with serum lipase activity within the reference range or elevated less than twofold included gastritis, gastric ulcer, cholestasis, phenobarbital-induced hepatopathy, colitis, copper hepatopathy, abdominal hematoma, apocrine gland adenocarcinoma, and thrombocytopenia with pneumonia. 相似文献
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73.
Felice LJ Dombrovskis D Lafond E Bartges J Osborne CA 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1990,19(3):86-89
A reproducible high performance liquid chromatography (HPLC) method was developed for analysis of uric acid in canine serum and urine. The method consists of precipitating serum proteins with phosphotungstic acid prior to HPLC analysis. Urine is analyzed after dilution with buffer. Chromatography is performed on a reversed-phase C-18 column with UV detection at 292 nm. Sensitivity of the method will allow reproducible measurement of uric acid at concentrations of 0.05 mg/dl in serum and 0.1 mg/dl in urine. The HPLC method has been used to quantify hundreds of canine serum and urine samples. The method is superior to UV absorption or colorimetric methods because its lower limit of detection allows measurement of uric acid at concentrations found in canine serum and urine. 相似文献
74.
Madhu Aneja Thomas J. Gianfagna Prakash K. Hebbar 《Physiological and Molecular Plant Pathology》2005,67(6):1647
An isolate of Trichoderma harzianum Rifai from an infected cacao pod produces and secretes nonanoic (pelargonic) acid into a liquid culture medium. Nonanoic acid (NA) was very inhibitory to spore germination and mycelial growth of two cacao pathogens, Crinipellis perniciosa Stahel and Moniliophthora roreri Cif. H.C. Evans. It was highly active causing 75% inhibition of spore germination in an in vitro assay at a rate as low as 0.09 μM for M. roreri and 0.92 μM for C. perniciosa. Mycelial growth was comparatively less sensitive to inhibition, but still there was a 75% reduction in growth with 0.62 μM in M. roreri and 151 μM NA in C. perniciosa. In contrast, NA did not affect Trichoderma mycelial growth or spore germination at concentrations that were inhibitory to the pathogens. 6-pentyl-α-pyrone was also produced and secreted into the medium by T. harzianum, however; it was not antagonistic to the cacao pathogens. Although a number of metabolites produced by Trichoderma spp. have been identified in the past, this is the first report of NA production and secretion by any Trichoderma. The results suggest that NA may play a role in the successful use of some Trichoderma spp. isolates in the biocontrol of fungal diseases of plants. 相似文献
75.
Hyun-Young Cho 《Pesticide biochemistry and physiology》2005,83(1):29-36
The structural gene for glutathione S-transferase in Oryza sativa was successfully cloned from a cDNA library by the polymerase chain reaction method. The deduced amino acid sequence of this gene showed 44-66% similarity to the sequences of the class phi GSTs from Arabidopsis thaliana and Zea mays. This gene was expressed in Escherichia coli with the pET vector system and the gene product was purified to homogeneity by GSH-Sepharose affinity column chromatography. The expressed OsGSTF3-3 was a homo-dimer composed of 24 kDa subunit and its pI value was approximately 7.3. The OsGSTF3-3 was retained on GSH affinity column and its Km value for GSH was 0.28 mM. The OsGSTF3-3 displayed high activity toward 1-chloro-2,4-dinitrobenzene, a general GST substrate and also had high activities towards acetanilide herbicides, alachlor, and metolachlor. The OsGSTF3-3 was highly sensitive to inhibition by benastatin A and S-hexyl-GSH. From these results, the expressed OsGSTF3-3 is a phi class GST and seems to play an important role in the conjugation of the chloroacetanilide herbicides. 相似文献
76.
甜樱桃芽酚类物质含量及相关酶活性变化与自然休眠的关系 总被引:5,自引:1,他引:5
以7年生甜樱桃‘红灯’和‘早红宝石’为试材, 研究了酚类物质含量及相关酶活性在自然休眠期间的动态变化, 探讨了温度对酚类物质含量的影响。结果表明, 甜樱桃芽酚类物质在自然休眠期间持续缓慢增加, 随休眠的结束, 含量急剧下降, 不同品种之间有差异, 自然休眠结束后总酚含量降至最低。花芽中的酚类物质含量略高于叶芽, 多酚氧化酶( PPO) 、苯丙氨酸解氨酶( PAL) 活性差别不大; 不同需冷量的品种之间差异明显。芽中PAL活性与总酚含量的变化趋势呈正相关。而PPO活性在自然休眠期间逐渐升高。低温(5℃) 促进酚类物质的积累, 中期使其提前达到高峰并进入下降阶段, 后期加速其降低;高温(20℃) 效果相反, 变温(5℃/20℃) 效果不明显。 相似文献
77.
78.
79.
哺乳犊牛的消化特点与蛋白质需要 总被引:7,自引:0,他引:7
本文从犊牛的消化生理特点出发,综述了犊牛出生后的生理特征及蛋白质、必需氨基酸的需要量,并对代乳品中蛋白质原料进行了论述。 相似文献
80.
长期培肥对土壤酶活性的影响 总被引:24,自引:0,他引:24
25a的有机肥长期定位试验地中土壤养分和有关酶活性研究表明:耕种和不同的培肥方式均能提高土壤养分的含量,明显地改善土壤的生物活性,其中对土壤脲酶和磷酸酶活性影响明显,多酚氧化酶显著性则较差。对土壤酶活性进行相关分析发现,土壤脲酶和碱性磷酸酶之间呈极显著正相关,且这两种酶与有关主要土壤肥力因子均呈显著或极显著正相关关系。揭示出了土壤脲酶和碱性磷酸酶活性可以用来作为评价土壤肥力的综合指标。 相似文献