基因外显子连接序列与相应内含子序列的相互作用

剪接后的内含子与相应mRNA序列的相互作用在基因表达调控过程中起着非常重要的作用。基于27个物种的核糖核蛋白基因序列,采用Smith—Waterman局域比对方法得到外显子连接序列与相应内含子序列的最佳匹配片段,分析了外显子连接序列上的匹配频率分布和匹配片段的序列特征。发现一些低等真核生物EJC结合区域的匹配频率明显低于其它区域,所有物种EJC结合区域的序列构成呈现出相对低的结构序。最佳匹配片段的平均长度和配对率分布与siRNA和miRNA的结合特征相同。推测EJC和内含子在与外显子序列结合的过程中存在相互竞争和相互协作的关系,内含子中部序列在基因表达调控过程中起着重要的作用。     

Seed dormancy and control of germination in Sisymbrella dentata (L.) O.E. Schulz (Brassicaceae)

• Seed germination responsiveness to environmental cues is crucial for plant species living in changeable habitats and can vary among populations within the same species as a result of adaptation or modulation to local climates. Here, we investigate the germination response to environmental cues of Sisymbrella dentata (L.) O.E. Schulz, an annual endemic to Sicily living in Mediterranean Temporary Ponds (MTP), a vulnerable ecosystem.
• Germination of the only two known populations, Gurrida and Pantano, was assessed over a broad range of conditions to understand the role of temperatures, nitrate, hormones (abscisic acid – ABA and gibberellins – GA) and after‐ripening in dormancy release in this species.
• Seed germination responsiveness varied between the two populations, with seeds from Gurrida germinating under a narrower range of conditions. Overall, this process in S. dentata consisted of testa and endosperm rupture as two sequential events, influenced by ABA and GA biosynthesis. Nitrate addition caused an earlier testa rupture, after‐ripening broadened the thermal conditions that allow germination, and alternating temperatures significantly promoted germination of non‐after‐ripened seeds.
• Primary dormancy in S. dentata seeds likely allows this plant to form a persistent seed bank that is responsive to specific environmental cues characteristic of MTP habitats.

     

Flow injection chemiluminescence determination of naphazoline hydrochloride in pharmaceuticals

A simple and sensitive flow injection chemiluminescence (FI‐CL) method was developed for the determination of naphazoline hydrochloride (NPZ). The method is based on the enhancing effect of NPZ on the weak CL signal from the reaction of KIO₄ with H₂O₂. Experimental parameters that affected the CL signal, including the pH of the KIO₄ solution, concentrations of KIO₄, H₂O₂ and disodium‐EDTA and flow rate were optimized. Under the optimum conditions, the increment of CL intensity was linearly proportional to the concentration of NPZ in the range 5.0 × 10^?6 to 70 × 10^?6 mol/L. The detection limit was 1.0 × 10^?6 mol/L and the relative standard deviation for 50 × 10^?6 mol/L NPZ solution was 2.8% (n = 11). In addition, a high throughput of 120 samples/h was achieved. The utility of this method was demonstrated by determining NPZ in pharmaceuticals. Copyright © 2013 John Wiley & Sons, Ltd.     

天门冬多糖对人工感染鸡传染性支气管炎的治疗试验

旨在评价复方天门冬多糖注射液对鸡传染性支气管炎的临床治疗效果,为鸡传染性支气管炎临床治疗提供依据。以复方天门冬多糖注射液临床给药剂量筛选试验为基础,分别设置高剂量组、中剂量组、低剂量组、药物对照组、阳性对照组及空白对照组,运用t检验和方差分析法对攻毒前后试验动物的相对体质量及试验结束后免疫器官指数进行统计分析,通过比较各组数据的显著性差异来评价复方天门冬多糖注射液对鸡传染性支气管炎的治疗效果。结果显示,复方天门冬多糖注射液能提高发病鸡的相对增量率,并促进发病鸡的生长发育。说明,复方天门冬多糖注射液对患病鸡的临床治疗效果显著,在实际生产中可以推广应用。     

A probabilistic approach to the construction of competing-risk life tables

"This paper aims to identify net and partial-crude probabilities in the competing-risk life table context, by using probabilistic approaches. Five types of lifelength random variables are defined to formulate these nonidentifiable probabilities. General expressions for net and partial-crude probabilities are first derived under independent risks assumptions. Two sets of explicit formulas for estimating the net and partial-crude probabilities are then derived in terms of the identifiable overall and crude probabilities by making the additional assumption of piecewise uniform distribution of the lifelength random variables. A study of the degree to which nonidentifiability can affect the net and partial-crude probabilities in a variety of situations is developed. An example from cross-sectional studies is employed to illustrate the methodology developed."     

Electro-transfer of small interfering RNA ameliorated arthritis in rats

RNA interference provides the powerful means of sequence-specific gene silencing. Particularly, small interfering RNA (siRNA) duplexes may be potentially useful for therapeutic molecular targeting of human diseases, although novel delivery systems should be devised to achieve efficient and organ-specific transduction of siRNA. In the present study, we demonstrated that electro-transfer of a siRNA-polyamine complex made efficient and specific gene knockdown possible in the articular synovium. Targeted suppression of the tumor necrosis factor-alpha gene through this procedure significantly ameliorated collagen-induced arthritis in rats. Our results suggest the potential feasibility of therapeutic intervention with RNA medicines for treatment of rheumatoid and other locomotor diseases.     

红花注射液对慢性低O2高CO2肺动脉高压的影响

目的：探讨红花注射液对大鼠在慢性低O2高CO2下肺动脉高压的抑制作用。方法：将SD大鼠分为对照组,慢性低O2高CO2组,慢性低O2高CO2＋红花注射液组。用电镜、放免等方法,观察各组大鼠肺动脉平均压、颈动脉平均压、肺细小动脉显微结构、血浆和肺匀浆TXB2及6-keto-PGF1a含量的变化。结果：①慢性低O2高CO2组mPAP比对照组显著增高,红花注射液组的mPAP比慢性低O2高CO2组显著降低,3组间mCAP比较差异无显著性。②慢性低O2高CO2组与对照组相比血浆和肺匀浆TXB2浓度、TXB2／6-keto-PGF1a比值显著增高,6-keto-PGF1a浓度显著下降;红花注射液组与慢性低P2高CO2相比血浆和肺匀浆TXB2浓度、TXB2／6-keto-PGF1a显著下降,6-keto-PGF1a显著升高。③光镜下慢性低O2高CO2组与对照组相比,肺细小动脉管壁面积／管总面积（WA／TA）和肺细小动脉中膜厚度（PAMT）均显著增高。红花注射液组WA／TA和PAMT显著降低。④电镜下慢性低O2高CO2组大鼠肺细小动脉内皮细胞吞饮小泡增多,血管壁增厚,中膜平滑肌细胞增生,纤维细胞增多,肺泡Ⅱ型上皮细胞微绒毛脱落;红花注射液组肺细小动脉中膜平滑肌细胞增生减轻,纤维细胞少,胶原纤维减少,肺泡Ⅱ型上皮细胞微绒毛丰富、结构清。结论：红花注射液有减轻慢性低O2高CO2性肺动脉高压和肺血管结构重建的作用,可能与抑制TXA2的合成,保护血管内皮细胞,使TXA2/PGI2比值降低有关.     

Modeling the dynamics of choice

A simple linear-operator model both describes and predicts the dynamics of choice that may underlie the matching relation. We measured inter-food choice within components of a schedule that presented seven different pairs of concurrent variable-interval schedules for 12 food deliveries each with no signals indicating which pair was in force. This measure of local choice was accurately described and predicted as obtained reinforcer sequences shifted it to favor one alternative or the other. The effect of a changeover delay was reflected in one parameter, the asymptote, whereas the effect of a difference in overall rate of food delivery was reflected in the other parameter, rate of approach to the asymptote. The model takes choice as a primary dependent variable, not derived by comparison between alternatives—an approach that agrees with the molar view of behaviour.     

比索洛尔联合丹红注射液治疗老年心肌缺血的临床疗效

目的:探讨比索洛尔联合丹红注射液对老年心肌缺血患者血清肌钙蛋白、心肌酶水平及临床疗效的影响。方法:收集我院收治的老年心肌缺血患者58例,随机分为观察组和对照组,每组各29例。所有患者均给予调脂、抗血小板和抗心肌缺血等基础治疗。对照组患者给予丹红注射液静脉滴注,观察组在对照组基础上给予比索洛尔治疗。观察并比较两组患者治疗前后的心肌酶(CK、CK-MB、AST、LDH)、血清肌钙蛋白I(c Tn I)、肿瘤坏死因子-α(TNF-α)水平及临床疗效。结果:与治疗前相比,两组患者治疗后心肌酶(CK、CK-MB、AST、LDH)、血清肌钙蛋白I(c Tn I)及肿瘤坏死因子-α(TNF-α)水平降低(P0.05);与对照组比较,观察组患者心肌酶(CK、CK-MB、AST、LDH)、血清肌钙蛋白I(c Tn I)及肿瘤坏死因子-α(TNF-α)水平较低(P0.05),临床总有效率较高(P0.05)。结论:比索洛尔联合丹红注射液对老年心肌缺血有较好的临床疗效。     

小鼠精子形成各阶段转基因效率的研究

在过去的近30年中,转基因技术在哺乳动物基因表达方面研究的应用已经成为实验生物学及应用生物学领域最为显著的进展之一．传统的制作转基因动物方法有显微注射法、逆转录病毒感染法和胚胎干细胞法等,但每种方法都有其缺陷,限制了其在今后转基因动物研究中的广泛应用．对小鼠体内生殖细胞进行外源基因转染,研究精子形成过程中制作转基因小鼠的效率．首先运用睾丸注射法将被脂质体包裹的绿色荧光蛋白表达载体(pIRES2-EGFP)注射到公鼠睾丸及附睾内,然后根据精子形成的不同阶段,分别于注射后7、16、30和42天与发情母鼠合笼,利用PCR和DNA印迹方法对新生小鼠进行基因组DNA检测．在各阶段所得新生小鼠中PCR阳性率分别为6.82%、0、56.86%和42.86%,DNA印迹检测阳性率分别为6.82%、0、47.06%、34.69%．经活体荧光成像系统及荧光显微镜分析,转基因小鼠呈现绿色荧光表达．通过比较精子生成各阶段转基因效率高低,为以后通过用睾丸内注射法转染雄性生殖细胞高效制作转基因动物提供了理论依据．