瘤胃上皮内的乳酸吸收及其转运载体蛋白研究进展

乳酸作为瘤胃内的中间代谢产物,其合理的清除与有效的利用在由高精料诱导的瘤胃酸中毒的研究中十分重要。现有研究表明,瘤胃上皮在乳酸吸收方面发挥着一定的作用,因此,本文从瘤胃上皮的乳酸吸收以及吸收过程中涉及的转运载体蛋白进行综述,为进一步了解乳酸在瘤胃内的转运过程提供理论依据。     

几种利用乳中尿素氮浓度估测尿氮排泄量模型的评价

本文利用34组国内外报道的荷斯坦牛乳中尿素氮浓度和尿氮排泄量的实测数据，对目前提出的部分利用MUN估测尿氮排泄量的模型进行了比较。结果表明，Zhai（2005）提出的模型[UN（g/d）：10．1×MUN（mg／dL）＋47.3]预测效果较好（P〉0．05）。划分MUN浓度范围分别建立模型可能会提高预测的准确度。此外，根据34组数据做简单回归：UN（g/d）=12．78×MUN（mg/d1）＋28．15（n=34，R2=0．59）。     

Characteristics of 18F-FDG and 18F-FDOPA PET in an 8-year-old neutered male Yorkshire Terrier dog with glioma: long-term chemotherapy using hydroxyurea plus imatinib with prednisolone and immunoreactivity for PDGFR-β and LAT1

An 8-year-old neutered male Yorkshire Terrier dog presented with head pressing, vestibular ataxia, neck tenderness, and no oculocephalic reflex. A demarcated lesion in the pons was identified on MRI. The patient was tentatively diagnosed with a glioma and was treated with hydroxyurea plus imatinib and prednisolone. After 30 days of therapeutic treatment, the patient showed a clear improvement in neurological signs, which lasted for 1117 days. On day 569 after the initiation of treatment, ¹⁸F-fluorodeoxyglucose (FDG)-positron emission tomography (PET) was performed with no significant findings on visual analysis. The average and maximal standardized uptake values (SUVs) were 1.92 and 2.29, respectively. The tumor-to-normal-tissue (T/N) ratio was 0.97. The first evidence of clinical deterioration was noticed on day 1147. On day 1155, 3,4-dihydroxy-6-[¹⁸F]-fluoro-l-phenylalanine (¹⁸F-FDOPA)-PET was performed. High uptake of ¹⁸F-FDOPA was observed in the intracranial lesion. The mean and maximal SUVs of the tumor were 1.59 and 2.29, respectively. The T/N ratio was 2.22. The patient was euthanized on day 1155 and histopathologic evaluations confirmed glioma (astrocytoma). This case shows that chemotherapy with hydroxyurea plus imatinib may be considered in the treatment of canine glioma. Furthermore, this is the first case describing the application of ¹⁸F-FDG and ¹⁸F-FDOPA in a dog with glioma.     

Prognostic factors in cats with chronic kidney disease

BACKGROUND: Chronic kidney disease (CKD) is a common cause of morbidity and mortality in cats. HYPOTHESIS: Some baseline variables are associated with shorter survival times in cats with CKD. ANIMALS: Client-owned cats. METHODS: Cats with CKD with initial plasma creatinine concentration > or =2.0 mg/dL and urine specific gravity (USG) < or = 1.025 were recruited into a prospective clinical trial that compared benazepril with a placebo. We describe baseline variables in 190 cats and their influence on renal survival time in the placebo group (95 cats), which was followed for up to 1,097 days. Renal survival time was defined as the time from initiation of therapy to the need for parenteral fluid therapy, euthanasia, or death related to renal failure. RESULTS: Of the 95 cats treated with a placebo, 58 were censored and 37 reached the renal survival end point (died, n = 0; euthanized, n = 17; parenteral fluids, n = 12; parenteral fluids followed by euthanasia, n = 8). Increased plasma creatinine concentration, increased urine protein-to-creatinine ratio (UPC), and increased blood leukocyte count were significantly (P < .01) associated with a shorter renal survival time and were independent risk factors. Increased concentrations of plasma phosphate or urea, and lower blood hemoglobin concentration or hematocrit were significantly (P < .01) associated with a shorter renal survival time and were dependent risk factors, because they also were significantly (P < .01) correlated with plasma creatinine concentration at baseline. CLINICAL IMPORTANCE: Several variables were significantly associated with a shorter renal survival time in cats with CKD.     

农用运输车行驶平顺性的模拟计算与分析

提出了四轮农用运输车的八自由度随机振动系统模型，对整车行驶平顺性进行了计算机模拟计算和分析计算结果得到了试验验证。     

基于模糊分析的农用运输车双万向传动轴可靠性优化设计

将模糊可靠性设计应用于农用运输车传动轴的优化设计,提出了农用车双万向传动轴的模糊可靠性优化设计方法,建立了在满足给定模糊可靠性要求设计条件下优化设计数学模型,并进行了实例计算。     

加强农用运输车管理 做好交通事故预防

近年来因农用运输车所造成的交通事故不断发生,且逐年呈现上升势头,本文从驾驶员的因素、车辆自身因素以及驾驶环境条件、职能部门的监管等方面对农用运输车交通事故的原因作了分析,提出了一些预防事故发生的措施。     

高亲和钾转运体在植物抗盐中的作用

土壤盐渍化是导致作物减产的一项重要原因,Na+对大多数作物是有害的,而钾是植物不可缺少的营养成分,植物根系在外界低钾条件下主要通过高亲和性系统吸收K+.介绍了高亲和钾转运体Trk/HKT和KUP/HAK/KT 2大家族的结构和功能.主要讨论了当植物处于K+饥饿及盐胁迫下,2大家族在改善植物钾营养、提高植物耐盐性方面的作用.     

Taurine alone or in combination with fish protein hydrolysate affects growth performance,taurine transport and metabolism in juvenile turbot (Scophthalmus maximus L.)

The study was conducted to investigate the effects of taurine (Tau) alone or in combination with fish protein hydrolysate (FPH) on growth performance, the expression of Tau transporter (TauT) and metabolic profile in juvenile turbot. FM, FPH0, FPH0+T, FPH10 and FPH10+T diets, respectively, contained 300, 150, 150, 80, and 80 g/kg fishmeal. FPH10 and FPH10+T diets contained 62 g/kg FPH. FPH0+T and FPH10+T diets were, respectively, prepared by supplementing the FPH0 and FPH10 diet formulations with 8 g/kg Tau. Specific growth rate was the highest in FM group and the lowest in FPH10 group. TauT mRNA levels in fish fed Tau supplemented diets were significantly lower than that in Tau unsupplemented diets. NMR‐based metabolomics analysis showed that Tau contents in liver of FPH0+T and FPH10+T were significantly higher than that of FM, FPH0 and FPH10. In muscle, Tau contents were significantly decreased in the FPH10+T versus FPH0 and the FPH10+T versus FPH10 comparisons. In conclusion, 62 g/kg FPH to replace fishmeal may not affect Tau synthesis, transport and metabolism. However, Tau supplemented alone or in combination with a certain level of FPH could reduce the requirement for Tau synthesis and transport and increased Tau levels in muscle and liver.