有机氮部分替代无机氮对香料烟产量、产值及品质的影响

为了提高香料烟的产量、产值和品质,采用田间小区试验研究了有机氮部分替代无机氮(取代比例分别为0、25%、50%)对香料烟产值及品质的影响。结果表明,有机氮取代部分无机氮对烤烟的产量、产值、上等烟比例和化学成分协调程度及矿质营养元素含量有很大的影响。其中,产量、产值和上等烟比例以有机氮取代50%无机氮处理最高,分别达到2 212.00kg/hm2、53 362.00元/hm2和70.22%。有机氮部分取代无机氮对香料烟叶片中化学成分、矿质元素的影响比较复杂,不同部位叶片以及不同化学成分的响应不同,但总体表现为有机氮取代无机氮改善了烤烟化学成分的协调程度,促进了有益矿质元素的积累。总之,对浙江省绍兴香料烟烟区来说,在施氮水平为105kg/hm2情况下,有机氮取代50%的无机氮时香料烟的经济产量、产值和烟叶品质较好。     

Mechanisms of Gastrointestinal Ischemia-Reperfusion Injury and Potential Therapeutic Interventions: A Review and Its Implications in the Horse

Restoration of blood flow after a period of intestinal ischemia is necessary to maintain cell function and viability; however, the reintroduction of oxygen can initiate a cascade of events that exacerbates tissue injury. Intestinal I-R injury is manifested as increased microvascular and mucosal permeability, and mucosal necrosis. Reperfusion injury begins with the accumulation of hypoxanthine from ATP metabolism and the conversion of XDH to XO during ischemia. Upon reperfusion, the XO catalyzes the conversion of hypoxanthine to superoxide radicals in the presence of oxygen. Superoxide radicals are further reduced to highly reactive hydroxyl radicals, which initiate lipid peroxidation. Lipoperoxidation causes functional and structural alterations in cell membrane lipids and can release numerous inflammatory mediators, which exacerbate tissue damage. Neutrophils are recruited into tissues during ischemia and on reperfusion; then they undergo degranulation and release destructive products (proteases and OFRs), which mediate further tissue injury. A limited number of experimental studies in the gastrointestinal tract of horses have shown I-R injury. Additional studies are necessary to further elucidate and sequence the precise pathophysiologic mechanisms occuring in the equine intestine during I-R. Therapy should be focused on prevention of I-R injury by pharmacologic or chemical inhibition or modification of these pathophysiologic pathways. Selected pharmacologic agents or drug combinations may offer novel, scientifically relevant and yet practical approaches to alleviating intestinal I-R injury in horses. This may improve survival of horses with naturally acquired intestinal strangulation obstruction.     

蒙古斑点马黑、白毛色区域皮肤中相关基因的表达研究

本试验以蒙古斑点马为研究对象,分别对蒙古斑点马体躯白色区域和黑色区域皮肤的表型和差异表达基因进行分析并验证,试图解析蒙古斑点马毛色形成的分子机制,为今后保护和开发利用蒙古斑点马奠定基础.选择蒙古斑点马体躯白色和黑色区域皮肤制作组织切片,HE染色后在显微镜下观察其表型差异;对白色和黑色区域皮肤组织进行转录组测序,比较差异...     

Plasma pro-opiomelanocortin, pro-adrenocorticotropin hormone, and pituitary adenoma size in dogs with Cushing's disease

It is difficult to predict the size of pituitary corticotroph tumors in dogs with Cushing's disease (pituitary-dependent hyperadrenocorticism [PDH]) without pituitary imaging techniques. The purpose of this study was to examine the relationship between plasma adrenocorticotropin hormone (ACTH) precursor concentration and pituitary size in dogs with Cushing's disease. Plasma concentrations of ACTH precursors (pro-opiomelanocortin [POMC]/pro-ACTH) and pituitary tumor height/brain area were measured in 36 dogs with pituitary corticotroph adenomas of various sizes. There was a correlation between tumor size (measured as the pituitary tumor height/brain area ratio [P/B]) and POMC/pro-ACTH concentration (r = .70; P < .0001). Dogs with P/B > or = 0.40 x 10(-2) mm(-1) had higher concentrations of ACTH precursors than dogs with P/B < 0.40 x 10(-2) mm(-1) (median concentration 85 pmol/L, range 15-1,350 pmol/L, n = 14 versus 15 pmol/L, range 15-108 pmol/L, n = 22; P < .0001). With a threshold of 35 pmol/L of POMC/pro-ACTH concentration, the estimated sensitivity and specificity of the kit were 93% (95% confidence interval [CI], 79-100%) and 86% (95% CI, 73-100%), respectively. We interpret these data as indicating that measurement of POMC and pro-ACTH might be of value in the characterization of tumor size in dogs with Cushing's disease. Low POMC/pro-ACTH concentrations make it unlikely that a large pituitary tumor exists in dogs with PDH.     

湖羊在西北寒旱地区行为学和生理指标的观测

为了研究西北寒冷干旱气候条件下湖羊的行为和生理指标变化,进而为西北地区湖羊引种提供数据支持和理论依据,本试验选用12只(公、母各半)舍饲周岁湖羊,通过近红外摄像技术研究了不同季节(A因子,A₁夏季,A₂冬季)、性别(B因子,B₁♂,B₂♀)和不同时段(C因子,C₁昼,C₂夜)条件下湖羊的采食、饮水、反刍、卧息等行为。结果表明,季节因子(A因子)对湖羊采食、卧息、反刍等行为均有极显著影响(P<0.01);性别因子(B因子)仅对湖羊采食和卧息行为有显著影响(P<0.05);昼夜因子(C因子)对湖羊的卧息行为有显著影响(P<0.05),对其采食和反刍行为有极显著影响(P<0.01)。季节和性别的交互作用对湖羊采食行为有显著影响(P<0.05),对反刍行为有极显著影响(P<0.01)。其余因子间交互作用对湖羊行为学无显著影响。试验羊体温、心跳、呼吸频率和血常规等生理指标均在正常范围内。以上结果说明湖羊在当地表现出了良好的适应性,在西北地区引种湖羊可行。     

Estimation of glomerular filtration rate in healthy cats using single-slice dynamic CT and Patlak plot analysis

Commonly used clinical indicators of renal disease are either insensitive to early dysfunction or have delayed results. Decreased glomerular filtration rate (GFR) indicates renal dysfunction before there is a loss of 50% of functional nephrons. Most tests evaluate global rather than individual kidney function. Dynamic computed tomography (CT) and Patlak plot analysis allows for individual GFR to be tested. Our objectives were to establish a procedure and provide reference values for determination of global GFR in 10 healthy cats using dynamic CT (CTGFR). This method of GFR determination was compared against serum iohexol clearance (SIC). A single CT slice centered on both kidneys and the aorta was acquired every fifth second during and after a bolus injection of iohexol (240 mgI/ml; 300 mgI/kg) for 115 s. Using data from this dynamic acquisition, Patlak plots were obtained, GFR was calculated, and results were compared to global GFR determined by iohexol clearance. The average global CTGFR estimate was 1.84 ml/min x kg (SD = 0.43; range = [1.22, 2.45]). The average global GFR measured using SIC was 2.45 ml/min x kg (SD = 0.58; range = [1.72, 3.69]). GFR measurements estimated by both dynamic CT and SIC were positively associated (estimated Spearman rank correlation coefficient = 0.72; P = 0.0234). The CTGFR method consistently underestimated GFR with a bias of -0.62 (SE = 0.1307) when compared to SIC (P = 0.0011). In healthy cats, CTGFR was capable of determining individual kidney function and appears clinically promising.