乌兰布和沙漠流动沙丘不同部位水分动态研究

通过对乌兰布和沙漠流动沙丘的不同部位沙土含水量的测定研究，结果表明：（1）乌兰布和沙漠流动沙丘3个不同部位的水分垂直变化趋势是一致的，0～60cm含水量变化幅度大，60～100cm变化幅度小，含水量最大值出现在20～60CITI，降雨主要影响60cm以上的沙土水分；（2）3种部位在时间变化上都表现为4～5月含水量最小，从6月开始含水量升高；（3）迎风坡含水量较其他部位大0．65％～0．9％，较背风坡大1．8％～2．5％，其他部位较背风坡大1％～1．7％，且3种地貌部位20～60cm处较80cm和100cm处有较大差异，同时迎风坡的变化幅度最大。     

Study on the activation of blood platelets by propylene-acidamide grafted polypropylene membrane in vitro

AIM: To evaluate the blood compatibility of a new bioartificial reactor membranous material (propylene-acidamide grafted polypropylene membrane, PP-g-AAm) in vitro. METHODS: Contacted PP-g-AAm membrane and PP (polypropylene) membrane with platelet-rich plasma in a swing bed, 37 ℃, to simulate the conditions in vivo, and another group of PRP without any membranes was set as control group. ELISA was used to study the expression of β-thromboglobulin, and flow cytometry was used to study CD62P and CD63 expression of the activated blood platelets after contacting the two kinds of membranes with PRP. Scanning electrical microscopy was used to study the configuration and numbers of platelet cells adhered on the membranes. RESULTS: After contacting with PRP 30 min, β-TG expression showed marked difference between the two kinds of material groups and the control group (P<0.01, P<0.05), and the difference between the two kinds of membrane groups was also significant (P<0.05). There were obviously differences on the expression of CD62P and CD63 between the two kinds of membranes after contacting with PRP for 30 min (P<0.05，P<0.01). When enlarged 10 000 times, the disfiguration of the platelet cells adhered on the two kinds of membranes after one hour were found by scanning electrical microscopy, and the numbers of platelets on the PP membrane were more than the PP-g-AAm membrane markedly. CONCLUSION: The PP-g-AAm membrane has better blood compatibility than the PP membrane.     

Effect of heme oxygenase on vascular remodeling in renal hypertension

AIM: To investigate the effect of heme oxygenase on vascular remodeling in renal hypertension. METHODS: Male Wistar rats were randomly divided into sham-operated, 2K1C （two-kidney one-clip） and hemin-induced groups. Four weeks after the treatments, the thickness of aortic media and HO enzymatic activity of the aorta were determined. Immunohistochemical staining was carried out to detect protein of HO-1 in the aorta. RESULTS: The blood pressure in 2K1C renal hypertension rats started to increase two weeks after the surgery and stabled at a high level at the 4th week. Hemin, an inducer of HO-1, markedly inhibited the increase in blood pressure. Aortic medium thickness of the 2K1C rats at 4th week was 27.5% thicker than that in the sham-operated rats. The thickness of aortic medium of the hemin-induced rats was 16.1% less than that in 2K1C group. At the 4th week after operation, protein level and enzymatic activity of HO-1 in aorta were higher than that in 2K1C group compared to those in the sham-operated group. CONCLUSION: Renal hypertension caused vascular remodeling and the activation of HO-1. HO-1 induction decreased the blood pressure of renal hypertension and reduced vascular remodeling.     

Effect of fluvastatin on migration of vascular smooth muscle cells from rats

AIM: To investigate the effect and mechanism of fluvastatin on the migration induced by platelet derived growth factor-BB (PDGF-BB) and endothelin-1 (ET-1) in cultured vascular smooth muscle cells (VSMCs). METHODS: Cultured VSMCs derived from spontaneously hypertensive rats (SHR) were used. Cell migration was determined by modified Boyden chamber assays. Intracellular free calcium (［Ca2+］i) was measured with fluorescent Ca2+ indicator Fura-2/AM. RESULTS: PDGF-BB and ET-1 significantly induced VSMCs migration, which was inhibited by pretreatment of VSMCs with fluvastatin (10-9-10-5 mol/L) in a dose-dependent manner, and the peak inhibition rate of migration induced by PDGF-BB and ET-1 was over 86.67%. Fluvastatin also attenuated the increase in ［Ca2+］i induced by PDGF-BB and ET-1, with a peak inhibition rate of 86.76% and 65.32%, respectively. CONCLUSION: PDGF-BB and ET-1 promote migration of VSMCs from SHR．Fluvastatin may have direct inhibitory effects on cell migration induced by PDGF-BB and ET-1. The increase in ［Ca2+］i may acts as intracellular signaling in the migration in response to PDGF-BB and ET-1 in VSMCs.     

Role of lipopolysaccharide in the development of hepatopulmonary syndrome

AIM: The goal of the present study was to evaluate the possibility about enterogenous endotoxemia in pathogenesis of hepatopulmonary syndrome. METHODS: The rat model of cirrhosis was prepared with compound factors. A small dose of lipopolysaccharide (LPS) was administered intraperitoneally once to aggravate endotoxemia of animal with cirrhosis. The normal rats injected with LPS or injected with LPS combined with glycine (LPS antagonist) were designed as controls. RESULTS: Hepatopulmonary syndrome of rats with cirrhosis had occurred in the end of eighth weeks. Pulmonary pathological changes of cirrhosis rats were exacerbated after administration of a given dose of LPS. Glycine sharply antagonized the biological effect of LPS in vivo and in vitro, inhibited the production of TNF-α by LPS and alleviated various pathological changes of hepatopulmonary syndrome. CONCLUSIONS: Enterogenous endotoxemia in cirrhosis rats might be an important mechanism in the development of hepatopulmonary syndrome. Endotoxin and its mediating effect by way of cytokines (TNF-α) may play a role in the pathogenesis of hepatopulmonary syndrome.     

非无菌操作下分离尖孢镰刀菌的培养基

 尖孢镰刀菌(F.oxysporum)是一类非常重要的土传病原真菌,寄主范围广,可引起100多种植物的萎蔫型病害。     

体外培育赤眼蜂研究进展

体外培育赤眼蜂的国内外研究已达到相当平：随着人工饲料配方的优化，选用的人工卵壳材料更适合于赤眼蜂的寄生与发，以及人工卵卡机的研制成功和性能不断改进，产业化体外培育赤眼蜂已成为可能。体外培育赤眼蜂的品质管理问题是实现产业化体外培育赤眼蜂的关键。然而，国内外对体外培育赤眼蜂的品质管理研究涉及甚少，有待进一步研究。本文指出应开展体外培育赤眼蜂生物学特性、行为学特性和分子生物学特性的研究，并应用于品质管理，建立体外培育赤眼蜂的品质管理体系，促进实现体外培育赤眼蜂产业化的进程，从而满足农业生产上对赤眼蜂种群的大量需要。另外，人工卵滞育贮存法的突破有助于实现体外培育赤眼蜂的产业化，也应加强研究，最后，本文对体外培育赤眼蜂的应用前景进行了展望。     

21 世纪的农业水土工程

介绍了农业水土工程学科的历史和形成过程,分析其在我国农业可持续发展中的地位和作用,提出了２１世纪中国农业水土工程学科需要解决的关键科技问题,探讨其在基础理论,应用持等方面的发展趋势。     

我国烟草业改革之路

针对目前我国烟草行业发展中存在的经营管理体制不完善、行业整体技术水平较低、“两烟“市场基本饱和、入世后国际竞争加剧及社会舆论环境对烟草行业的发展压力加大等问题,提出了深化烟草行业体制改革,大力推进企业组织结构调整,建立和完善专卖制度下适应市场经济要求的烟草市场体系等改革发展思路。