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931.
AIM: To explore the regulatory effect of intermedin (IMD) on pulmonary collagen synthesis and accumulation in rats with pulmonary hypertension induced by high pulmonary blood flow.METHODS: Healthy male SD rats (n=20) were randomly divided into control group (n=7), shunt group (n=7) and shunt with IMD group (n=6). The shunting of abdominal aorta and inferior vena cava was produced in rats of shunt group and shunt with IMD group. After 8 weeks, IMD was administered into the rats of shunt with IMD group subcutaneously by mini-osmotic pump for 2 weeks. Mean pulmonary artery pressure (mPAP), relative medial thickness (RMT) of pulmonary arteries, contents of hydroxyproline, collagen type I and III, bone morphogenetic protein-2 (BMP-2), and the mRNA expression of procollagen I and III in lung tissues were measured and compared. RESULTS: Compared with control group, mPAP and RMT of medium and small pulmonary arteries in the rats of shunt group were significantly increased. Meanwhile, the lung hydroxyproline, collagens I and III and BMP-2 contents, and the mRNA expression of lung procollagen I and III were all significantly increased compared with control group. However, IMD significantly decreased mPAP, alleviated the changes of pulmonary vascular micro-structure, decreased the collagen accumulation and pulmonary tissue homogenate BMP-2 contents, and inhibited the mRNA expression of procollagen I and III in the lung tissue of shunting rats.CONCLUSION: IMD plays a protective role in the development of pulmonary hypertension and pulmonary vascular structural remodeling induced by high blood flow by inhibiting pulmonary collagen synthesis and accumulation, possibly in association with the BMP-2 pathway. 相似文献
932.
与黄瓜霜霉病抗性相关基因连锁的分子标记研究 总被引:1,自引:0,他引:1
以黄瓜抗霜霉病和感霜霉病亲本组合(Q9×Q10)的F2分离群体为试材,采用BSA法筛选到了1个AFLP引物组合P11M70在抗病池和感病池间表现多态,抗病池和抗病亲本均具有大小约304 bp的特异谱带,感病池和感病亲本均扩增出了大小约为301 bp的特异片段。经F2单株验证及连锁分析,该特异片段与霜霉病抗病相关基因相连锁,连锁距离为5.22 cM。对特异片段的测序结果显示,两片段的大小分别为304 bp和301 bp,且2个片段的差异仅为3个"A"碱基的插入或缺失以及1个"C-T"的碱基突变。将该AFLP标记成功地转换为了简单实用的SCAR标记。 相似文献
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936.
试验旨在探讨低蛋白日粮对育肥猪养分消化率和排泄量的影响。选用42头初始体重为(91.13±1.64)kg的杜长大育肥猪分为2组,每组3个重复,分别饲喂粗蛋白水平为15.49%(对照组)和12.59%(低蛋白组)的日粮。试验期30d。结果表明:(1)低蛋白组干物质、粗脂肪消化率显著提高(P0.01),粗蛋白、钙、磷消化率无显著变化;(2)低蛋白组精氨酸、天冬氨酸、异亮氨酸消化率比对照组分别低2.02%(P0.05)、5.42%(P0.05)、2.97%(P0.05),苏氨酸、蛋氨酸、脯氨酸消化率较对照组分别提高2.93%(P0.05)、1.43%(P0.05)、1.19%(P0.05);(3)低蛋白组育肥猪每天的氮排泄量比对照组低23.96%(P0.05),而有机物、磷、钙排泄量无显著差异(P0.05)。试验结果显示,日粮蛋白水平降低2.9个百分点可以改善养分的消化率,减少氮排放,但降低了精氨酸的消化率。 相似文献
937.
为研究长沙市生态动物园引进的非洲肯尼亚斑马蜱的线粒体DNA的部分细胞色素C氧化酶第Ⅰ亚基(cytochrome coxidase subunit l,pcox1)基因序列的遗传变异情况,本研究对其线粒体pcox1基因序列进行PCR扩增,并使用DNAStar(V5.01)、Clustalx2.0及Phylip3.67进行分析。结果显示,几种斑马蜱为消色牛蜱、丽色扇头蜱和璃眼蜱属,种间差异为0.7%~20.2%,种内相似度较高,表明pcox1基因可作为蜱种间遗传变异研究的标记,研究结果为蜱的分类鉴定以及进一步的分子流行病学调查奠定了基础。 相似文献
938.
核因子-κB(NF-κB)在炎症反应中起着关键的促进作用,并且受其他多种因素的调节。Nfkbiz基因编码的IκB?蛋白是IκB家族成员之一,在炎症反应中起着调节NF-κB的作用。本研究采用荧光实时定量PCR分析Nfkbiz基因的表达情况,发现在p53特定刺激源作用下Nfkbiz基因mRNA丰度显著降低。分析Nfkbiz基因序列,发现其基因中存在可能的p53反应元件,通过构建荧光素酶报告质粒及双荧光素酶报告试验和染色质免疫共沉淀试验,证明Nfkbiz基因中含有p53反应元件并且受p53蛋白调节。以上结果初步证明Nfkbiz是受p53蛋白负向调控的靶基因。 相似文献
939.
Weiguo DU Travis R. ROBBINS Daniel A. WARNER Tracy LANGKILDE Richard SHINE 《Integrative zoology》2014,9(3):360-371
Geographic variation in life‐history traits among populations of wide‐ranging species is influenced by both spatial and temporal aspects of the environment. Rarely, however, are the effects of both aspects examined concurrently. We collected gravid female lizards (Sceloporus undulatus) from northern (Indiana), central (Mississippi) and southern (Florida) populations, spanning nearly the full latitudinal range of the species, to examine amongpopulation differences in strategies of reproductive energy allocation. Adult females from the southern population were smaller, and produced fewer and smaller eggs in their first clutches than did females from the more northern populations. Southern females were more likely to produce a second clutch, and second clutches were smaller than first clutches for females from the 2 northern populations. Together these trends eliminated population differences in overall reproductive output after accounting for body size. The trend for greater reproductive energy to be allocated to first clutches at higher latitudes, and to later clutches at lower latitudes is corroborated by published data from field studies on multiple populations. Distributing reproductive effort by producing more clutches of smaller eggs may be an adaptive response to the long season available for egg incubation and lizard activity in sub‐tropical southern environments. In contrast, allocating greater resources to early reproduction may enhance maternal fitness in the relatively short activity seasons that characterize more northern sites. 相似文献
940.