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91.
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93.
Clinicopathological Phenotype of Autosomal Recessive Cholesterol Deficiency in Holstein Cattle
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94.
Zandvliet MM Rothuizen J 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(2):215-218
BACKGROUND: Irish Wolfhounds frequently have a congenital portosystemic shunt, but a considerable proportion of the 6- to 8-wk-old pups has hyperammonemia in the absence of portosystemic shunting. This hyperammonemia causes no signs and is transient, normalizing at the age of 3-4 months. HYPOTHESIS: Transient hyperammonemia has a metabolic basis in Irish Wolfhounds. ANIMALS: Two related (same sire) litters of Irish Wolfhounds (17 pups) and their parents were studied. METHODS: Integrity of the portal circulation was examined by ultrasonography and scintigraphy. Absence of parenchymal liver disease was verified by liver biopsy. Amino acid profiles were measured in 4 pups and repeated in 2 of these pups when ammonia concentrations had normalized. The amino acid profiles were compared with those of healthy Irish Wolfhound pups. RESULTS: Fasting venous ammonia concentrations were high (113-622 microg/dL, 65-345 micromol/L) in all pups, whereas bile acids were within reference range in all but 1. The ammonia and bile acid concentrations from all parents were within reference range. Portosystemic shunting was excluded in all but 1 pup. Liver biopsy excluded significant lesions in all 10 pups examined. Hypercitrullinemia was found and persisted even when ammonia had normalized, at the expense of an increase in glutamine and asparagine. CONCLUSIONS AND CLINICAL IMPORTANCE: Citrulline concentrations are controlled by the urea cycle enzymes argininosuccinase and argininosuccinate synthetase, and a defect in either of these enzymes may be responsible for the transient hyperammonemia in Irish Wolfhounds. Resolution of the hyperammonemia is associated with increased activity of alternative metabolic pathways forming glutamine and asparagine. Confirmation requires measurement of enzyme activities in liver tissue. 相似文献
95.
以陕西长武旱塬为例,分别对研究区农地和5个不同林龄(9、12、16、19 a和23 a)苹果园的土壤剖面氢氧稳定同位素进行测定,利用Craig-Gordon模型定量估算其土壤平均蒸发量,并基于“空间换时间”方法分析果园种植及生长对土壤蒸发的影响。结果表明:农地及9、12、16、19、23 a林龄苹果园的土壤蒸发量均随苹果树的种植及生长呈现先减少再增大的趋势,年均蒸发量分别为129、104、89、119、128、136 mm;苹果园的土壤蒸发量变化与叶面积指数呈显著负相关(R=-0.713);苹果园种植的前中期(9~12 a)土壤蒸发量随叶面积指数增加逐渐减小,而在中后期(12~23 a)深层土壤水被大量消耗造成的干旱胁迫使得果树叶面积减少,从而导致林下土壤蒸发量又逐渐增大。 相似文献
96.
氮素营养水平对小麦后移栽棉氮代谢的影响 总被引:9,自引:1,他引:9
对不同氮素营养水平下的小麦后移栽棉叶片硝酸还原酶活性、棉株含氮量及叶片氨基酸含量等进行了测定。结果表明,除8月19日外,叶片硝酸还原酶活性与施氮量呈极显著正相关(r=0.9693~0.9881);地上部各器官的含氮率和绝对含氮量均随施氮量的增加而提高,且不同器官间呈同步增减的趋势,因而氮素分配比例的变化不大;提高氮素营养水平可显著增加小麦后移栽棉的叶片氨基酸总量和游离氨的含量(r=0.5316和0.5605),在17种氨基酸中,谷氨酸、脯氨酸等7种氨基酸的含量与施氮量呈显著的正相关(r=0.5256~0.6074)。虽然施氮量越高,棉株的氮素代谢越旺盛,但小麦后移栽棉的适宜施氮量约为205kg/hm2。 相似文献
97.
The cavity induced by top-blow gas jets impinging on the bath surface is one of most important parameters, which has overwhelming influence on the rate of slag formation and metallurgical performance. Water model experiments are conducted through a 1/10 scaled-down top-blown convertor. Effects of lance height and gas flow rate on penetration behavior are studied, and also the influence mechanism of liquid surface tension on penetration depth is addressed based on the experiments and theory analysis. An energy utilization index (EUI) is defined to reflect how much the impinging kinetic energy of gas jets are transferred into bath for formation of cavity, and an improved model is proposed to predict penetration depth of jets. The results show that penetration depth increases with lowering lance height and increasing gas flow rate, and impact diameter increases with increasing lance height, but is little affected by gas flow rate. Influence of liquid surface tension on penetration depth is enhanced with increasing surface tension and penetration depth. The EUI increases with increasing lance height, and a function relationship of it with lance height is obtained based on the experiments. 相似文献
98.
Gu Qiankun Tang Yike Yu Youju Xie Zhijiang Liang Xichang 《保鲜与加工》1997,(6):96-102
The dynamic characteristic of active isolation atuator on flexible foundations was studied under the installation of parallel structure and foundation cancellation.The influencing relationships between active isolation force of the different installation ways and passive isolation system and flexible foundation were analyzed and compared.Scientific basis for selecting installation ways of active isolator is provided in this paper. 相似文献
99.
100.
高氨氮厌氧消化液后处理技术研究 总被引:2,自引:0,他引:2
采用SBR-絮凝沉淀-Fenton氧化-活性炭吸附组合工艺对高氨氮厌氧消化液的后处理进行实验研究.结果表明,当进水COD浓度为4516 mg·L^-1时,SBR出水COD可降为1752 mg·L^-1,去除率达到61.2%;絮凝沉淀出水COD浓度为1189 mg·L^-1,去除率为32.1%;Fenton氧化和活性炭吸附出水COD浓度分别为452和216 mg·L^-1,去除率分别为61.7%和52.7%.当进水NH3-N浓度2162 mg·L^-1时,SBR出水NH3-N浓度降至13.8 mg·L^-1,去除率为99.4%,NH3-N主要在该段去除.整个组合工艺对COD和NH3-N的去除率分别达到95.2%和99.9%,达到了很好的有机物和氨氮去除效果,在技术上是可行的. 相似文献