谈中小桥采用后张法16m预应力空心板的施工问题

本文阐述了中小桥上部结构采用后张法１６ｍ预应力空心板的施工时应注意的问题，如预应力空心板的预制中底模的施工；侧模、蕊模；砼的要求；浇筑空心板的具体步骤。     

甘肃日光节能温室桃树促早栽培实践与思考

由于果树集约化栽培的发展,小冠整形及矮密栽培技术的推广,现代工业提供的园艺设施及园艺材料的应用,加之果品淡季上市的高额利润,刺激了果树设施栽培的迅速发展.迄今为止,进入设施栽培的树种达35种之多.     

农作物害虫标本数据库的开发研究

数据库包括鳞翅目、鞘翅目、半翅目、同翅目、双翅目、膜翅目、直翅目、蜱螨目和缨翅目等149种农作物害虫,原色图812幅和害虫防治技术信息。     

Effect of lactacystin and β-lactacystin on the activation and proliferation of T-lymphocytes

AIM: To evaluate the effects of lactacystin (LAC) and β-lactacystin (β-LAC), proteasome inhibitor, on the proliferation and activation of T lymphocytes. METHODS: Flow cytometry was used to analyse the proliferation and the expression of CD69, CD25 and CD3 in PHA activated T-lymphocytes. Furthermore, the expression of PA28 and IL-2 mRNA were assayed by competitive RT-PCR. RESULTS: (1) LAC and β-LAC significantly decreased the incorporation in PHA activated T-lymphocytes. (2) Although LAC and β-LAC did not affect the expression of CD69 at any time, they significantly inhibited the expression of CD25 (48 h, 72 h, P＜0.05). (3) In comparison with control, LAC and β-LAC significantly down-regulated the expression of PA28 and IL-2 mRNA (48 h, 72 h, P＜0.05).CONCLUSIONS: LAC and β-LAC significantly inhibit the proliferation and activation of T lymphocytes. Mechanisms involved are inhibition of CD25 and down-regulation of PA28 and IL-2 mRNA expression.     

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.     

Relation between the time-spatiotemporal expression of caspase-9 and photoreceptor apoptosis as well as electroretinography in RCS rats

AIM: To investigate the relation between the time- spatiotemporal expression of caspase-9 and photoreceptor apoptosis as well as electroretinography (ERG) in Royal College of Surgeons (RCS) rats. METHODS: Twelve non-pigmented degenerative RCS rats at age of 15, 20, 25, 30 days were sacrificed after ERG examination. The caspase-9 expression was analyzed with immunohistochemical staining, fluoro-metric activity assay and Western blotting. Apoptotic retinal neurons were detected by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) technique. RESULTS: The latency and amplitude of b-wave were (58.60±3.42) ms and (109.07±14.50) mV, (56.45±1.08) ms and (109.00±7.35) mV, respectively, in 15 and 20 days old degenerative RCS rats. The ERG resembled flat form in the degenerative RCS rats at age of 25 and 30 days. TUNEL-positive cells were located only in the outer nuclear layer, mostly prevailed in 25-day-old group. Caspase-9 protein expressed in the rat retina started to be found immunohistochemically in 25-day-old and was most predominant in the inner segment. Fluorometric activity assay showed that caspase-9 activity reached its peak, (10.98±0.13) nmol·g-1·min-1 at 20th day. Western blot assay revealed the small cleavage fragmentation at 20th day. No cleavage fragmentation was revealed in the 15-day-old degenerative RCS rats and all other control rats. CONCLUSION: The activation and time-spatiotemporal expression of caspase-9 are coincidence with photoreceptor apoptosis as well as the loss of vision function in RCS degenerative rats, which implicates the important role of caspase-9 in photoreceptor apoptosis.     

广西10个地方优质品种鸡γ-干扰素基因的克隆与序列分析

根据基因库中鸡γ-干扰素的基因序列设计了1对特异性引物，应用反转录-聚合酶链式反应（RT-PCR）技术，从ConA诱导培养的广西10个地方优质品种鸡外周血淋巴细胞RNA中扩增了γ-干扰素基因，结果，均得到了大小为520 bp的特异性片段。将扩增产物纯化并克隆到pMD18-T载体上，获得重组质粒，经PCR和EcoRⅠ＋SalⅠ双酶切鉴定后测序。序列分析结果表明，广西10个地方优质品种鸡γ-干扰席基因均编码145个氨基酸的成熟蛋白，分子质量约为16．8ku，与哺乳动物和其他品种鸡的核苷酸序列同源性分别为38．8％～39．0％和99．2％～100％，氨基酸序列同源性分别为23．69／6～24．8％和97．6％～99．4％。     

国外土地整理实践对我国土地整理的启示

土地整理在我国起步较晚，很多理论还不成熟。采用文献参阅法，从土地整理的发展阶段、内容和特点等方面介绍了德国、俄国和荷兰等国外土地整理的基本情况，并由此得出其对我国土地整理的启示：建立健全土地整理法律政策，重视土地整理的权属调整，拓宽土地整理融资渠道，重视土地整理中的生态环境保护，积极推动土地整理公众参与和高度重视土地整理规划等。     

我国农业保险发展经营模式研究

我国农业灾害损失相当严重，农业保险是有效分散农业风险促进农业和农村经济发展的重要手段，针对我国实际国情，选择合适的农业保险发展模式十分重要。本文在分析了国内外各种农业保险发展模式的基础上，提出了我国农业保险发展模式。并对其进行了深入分析。     

西吉县小麦丰产抗锈病品种综合分析选优

2003~2005年进行了冬春小麦42个水旱地品种的比较试验,运用灰色关联综合评价方法,筛选出西吉县丰产抗条锈病品种:冬小麦水地品种静冬9717、静冬941、静冬9718,旱地品种8802、陇原935、陇原992综合性状较好且抗条锈病;春小麦水地品种宁春4号、802-15、定丰806;旱地品种93-163-6、陇春8139-2综合性状较优,除宁春4号较易感条锈病外,其它品种均抗锈病。抗病品种比感病品种提高产量15.40%~61.12%。建议今后在西吉县大面积推广种植这些品种时,水浇地要特别注意宁春4号品种的条锈病预测及防治工作。