Protective effect and mechanism of ulinastatin on rats with hemorrhagic shock

AIM: To investigate the protective effect of ulinastatin on rats with hemorrhagic shock. METHODS: A prospective, controlled animal study was designed. The model of hemorrhagic shock in rats was produced by Chaudry method. After 60 min, rats were resuscitated by transfusion of shed blood and normal saline, but a half of them were treated with ulinastatin. At different time points after reperfusion, the levels of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), malondialdehyde (MDA) and superoxide dismutase (SOD) in serum were detected. RESULTS: The levels of TNF-α, IL-6 and MDA significantly increased and the activity of SOD decreased. In the ulinastatin-treated groups, the blood pressure and heart rate were obviously improved; the levels of TNF-α, IL-6 and MDA significantly decreased and the activity of SOD had little change after hemorrhagic shock and reperfusion. CONCLUSION: Ulinastatin has a protection effect on rats with hemorrhagic shock by suppressing the production of inflammatory factors and reducing oxidative damage.     

六株黑木耳两种同工酶的研究

本文对黑龙江省常用六株黑木耳菌种的胞内、胞外酯酶 (EST)及过氧化物酶 (POD)同工酶进行研究 ,结果表明 :黑木耳菌株同一培养时期的各菌株间同工酶谱存在明显差异 ,同一菌株的胞内、胞外同工酶在酶含量和酶带数也存在差异。此差异性可以用来进行菌种鉴定。     

阴山北麓农牧交错带景观生态设计——以察右后旗为例

从地处农牧交错带的察右后旗景观生态条件及资源状况着手,在基于土壤类型单元的土地农业适宜性综合评价的基础上,以最佳经济效益为目标,设计出一个生态治理与资源开发并举的,林草田复合的生态经济系统。     

浑善达克沙地南缘飞播固沙植物群落特性的研究

从1998~2001年连续4年对浑善达克沙地南缘飞播固沙植物群落特性研究的结果表明,其主要影响因子是土壤含水率。沙蒿(Artemisia arenaria DC.Prodr.)飞播8年后群落基本趋于稳定。其密度为1500株/hm2左右,盖度为10%左右;杨柴(Hedysarum mongolicum Turcz.)和沙打旺(Astragalus ad-surgens Pall CV.'shada wang')群落密度为800~1000株/hm2,盖度为12%左右。     

农业经济管理分类的研究

运用多元统计分析中的分层聚类分析和判别分析方法,借助SPSS统计软件进行统计分析,以西藏自治区的35个农业县为研究对象,根据2007年西藏农业县农林牧渔业产值、粮食产量、工业总产值等主要统计指标为分类变量,对农业县进行分类,根据所得出的结论,客观、合理地提出合理性的建议.     

草原返青期遥感监测分析

为全面掌握草原生产力动态变化,应用EOS/MODIS卫星数据结合地面样方和气候资料,对锡林郭勒草原2003-2007年返青状况进行动态监测。结果表明:2007年返青正常与较好的草原占88.85%,全盟平均每hm²鲜草产量达574.5kg,平均盖度35%,比2006年同期产草量增加1.5倍,盖度增加2倍;与近5年同期相比,2007年春季草原长势很好,近年全盟草原已向恢复趋势发展,历年植被长势和产草量的波动与降水量、热量的动态变化格局基本一致,可能与近年来大面积实施休牧、禁牧等草原保护措施,及大力推行草畜平衡制度有关。     

Actin rearrangements accompanying Aeromonas hydrophila entry into cultured fish cells

Aeromonas hydrophila can enter fish cells and exist as intracellular parasites. Phase-contrast and confocal microscopy were used to examine morphological changes and various cytoskeletal components of infected fish cells. Four fish cell lines were included in this study: (1) AS, (2) BF2, (3) CHSE-214, and (4) EPC cells. Virulent but not avirulent strains of A. hydrophila PPD 134/91 invaded fish cells, causing morphological changes, and inducing microfilament (F-actin) rearrangement. Morphological changes were observed in all infected fish cell lines and could be classified into three different stages. In stage I, the cells became detached from each other and pointed ends were observed. In stage II, tubular cytoplasmic extensions formed at contact points connecting neighbouring cells. The monolayers formed a satellite-like organization and became less confluent. Finally (stage III), cells were heavily infected with bacteria, and bacteria containing vacuoles occupied most of the cells. They eventually detached and lysed. Rearrangement of F-actin was observed as local polymerization (actin clouds) in stage I and massive reorganization in stage III of infection. Actin clouds could have been induced by A. hydrophila for ‘assisted' uptake into the cells. The massive reorganization of actin in stage III may be due to products released by the bacteria and the growth of vacuoles. Pretreatment of fish cells with the microfilament inhibitors such as cytochalasins induced a similar effect. There were little if any rearrangements in intermediate and microtubule filaments during bacterial entry (stages I and II). These results suggest that A. hydrophila may bind to the surface and trigger a signal to the microfilament which then generates the force necessary for bacterial uptake.     

大青山落叶松人工林直径分布规律的研究

本文运用正态分布、weibull分布和β分布3种概率密度函数,研究了内蒙古大青山32块落叶松人工林标准地的直径分布规律。结果表明,内蒙古大青山落叶松人工林的直径分布用β分布拟合效果较好,在此基础上建立了β分布参数的预估方程,预测林分理论直径分布,为华北落叶松人工林的科学经营提供理论依据.     

Alleviation of arsenic toxicity by phosphate is associated with its regulation of detoxification,defense, and transport gene expression in barley

Arsenic(As) contamination in soils has posed a severe threat to safe crop production. The previous studies showed the antagonism between phosphorus(P) and As in plant growth and As uptake, while the mechanisms of alleviating As toxicity by P is not completely clear. Due to the limiting P condition, it is imperative to understand how low P addition can be used to suppress arsenate As(V) uptake and the subsequent mechanisms involved. Thus in this study we investigated the effect of P addition on As uptake, anti-oxidative enzyme activity, and anti-oxidant content, and the relative expression of transport, defense, and detoxification genes using two barley genotypes differing in As toxicity tolerance. P addition significantly reduced As concentration in plant tissues, and caused the great changes in activities of catalase and superoxide dismutase, glutathione content, and the relative expression of examined genes when the plants of the two barley genotypes were exposed to 100 μmol L~(–1) As, with ZDB160(As-tolerant) being much more affected than ZDB475(As-sensitive). The current results show that P addition can alleviate As toxicity by regulating the expression of As transport, defense, and detoxification genes to a greater extent in As tolerance of barley, suggesting the possibility of controlling As uptake and toxicity by applying low amount of P fertilizers in the As-contaminated soils.     

浅谈森林资源的社会和生态效益的经济评价

随着经济和社会的发展,人们对森林资源、环境、经济之间的关系有了更进一步的认识。森林资源被认为是保障地球前途、维持人类生存和发展的重要因素。因此,应该积极开展森林资源的社会、生态效益的经济评价。