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91.
本研究以河西走廊荒漠绿洲边缘关键天然固沙植物沙拐枣为研究对象,对流动沙丘、固定沙丘不同生境的沙拐枣种群扩张特征进行调查,旨在更全面地认识其种群扩张特征和对干旱高温环境的适应对策。结果表明:(1)沙丘不同生境,沙拐枣种群扩张方式存在显著差异:在流动沙丘,丘间低地和过渡带以有性繁殖为主,无性繁殖为辅;迎风坡和背风坡以无性繁殖为主;而随着流动沙丘固定,种群以有性繁殖为主,无性繁殖数量和所占比重显著下降,并导致种群数量下降。(2)不同生境中沙拐枣种群密度与年龄均呈显著负相关,种群以幼龄苗为主,种群最大年龄出现在丘间低地,为36龄。(3)流动沙丘不同生境根状茎主要为2年生,多年生根状茎长度较短;而固定沙丘不同生境根状茎年龄结构较为均衡。  相似文献   
92.
利用5个锈病成株期抗性基因的KASP标记Sr2_ger9 3p、Lr34jagger、CSTM4_67G、Lr68-2、VPM_SNP和抗赤霉病基因Fhb1的KASP标记TaHRC-KASP,对云南省育成的42个小麦品种(系)进行检测,旨在筛选出含有目标基因的优异小麦种质,为云南省持久抗病小麦新品种(系)的选育提供材料。结果表明,4个材料含兼抗型成株抗锈病基因Lr34/Yr18/Sr57,频率为9.52%;6个品种(系)含兼抗型成株抗锈病基因Lr67/Yr46/Sr55,频率为14.29%;7个材料含抗慢叶锈病基因Lr68,频率为16.67%;含兼抗型成株抗锈病基因Sr2/Yr30和成株抗叶锈基因Lr37的材料各有1个,频率均为2.38%;未检测出含抗赤霉病基因Fhb1的品种(系)。云麦69、云麦75、云麦56、宜麦1号和宜麦3号等兼有2个成株期抗锈病基因,可作为今后云南持久抗锈病育种的抗源材料。  相似文献   
93.
AIM: To observe the therapeutic effect of Jiedu-Qingfei mixture on Mycoplasma pneumoniae (MP)-infected rat lung tissues and to explore its mechanism. METHODS: SD rats (n=40) were randomly divided into 4 groups:blank control group, model group, Jiedu-Qingfei group and positive control group, with 10 rats in each group. The rats in experimental groups were slowly dripped with 1×109 CFU/L MP solution into their nostrils for 4 d. One rat in each group was sacrificed for MP nucleic acid detection at the second day after inoculation, and the other rats were given gavage therapy. The rats in blank control group and model group were intragastrically given the same volume of normal saline, the rats in Jiedu-Qingfei group were given 8 mL/kg Jiedu-Qingfei mixture daily for 4 weeks, and the rats in psoitive control group were given dexmethasone sodium phosphate (0.5 mg·kg-1·d-1). After the experiment, the rats were killed. The serum and bronchoalveolar lavage fluid (BALF) were collected for detecting the levels of interleukin-12 (IL-12), IL-13 and TNF-α by ELISA. The right lung tissues were used for pathological observation and HE staining, while the left lung tissues were used to detect the expression of NF-κB p50, I-κBα and p38 mitogen-activated protein kinase (p38 MAPK) at mRNA and protein levels. RESULTS: The results of MP nucleic acid detection showed that all the rats except blank control group were MP nucleic acid positive, indicating that the rat model of MP infection was successfully established. On the 1st day of the treatment, the pathological scores of the lung tissues in model group and Jiedu-Qingfei group were significantly higher than those in blank control group (P<0.05). After treatment, the pathological scores of the lung tissues in mo-del group were significantly higher than those in blank control group and Jiedu-Qingfei group. The levels of IL-12 in the serum and BALF in model group were significantly lower than those in blank control group after MP infection (P<0.05), while those after treatment with Jiedu-Qingfei mixture were significantly higher than those in model group (P<0.05). The levels of IL-13 and TNF-α in the serum and BALF of MP-infected rats were increased significantly, while those after treatment with Jiedu-Qingfei mixture were significantly lower than those in model group (P<0.05). The mRNA expression levels of NF-κB p50 and p38 MAPK in model group were increased significantly (P<0.01). After treatment, the mRNA expression levels of NF-κB p50 and p38 MAPK were decreased significantly compared with model group (P<0.01). The mRNA expression level of I-κBα in model group was significantly lower than that in control group. After treatment, the mRNA expression of I-κBα in Jiedu-Qingfei group was significantly higher than that in model group (P<0.05). The protein levels of NF-κB p50 and p38 MAPK in the lung tissues of model group were significantly higher than those of blank control group. After treatment, the protein expression of NF-κB p50 and p38 MAPK was decreased significantly. The protein level of I-κBα in model group was significantly lower than that in blank control group, and after treatment with Jiedu-Qingfei mixture, the protein expression level of I-κBα was increased significantly (P<0.05). CONCLUSION: Jiedu-Qingfei mixture may attenuate lung tissue inflammation caused by MP through NF-κB and p38 MAPK pathways.  相似文献   
94.
Due to the growing interest in Central and Eastern Europe on cropping of wheat in optional late autumn terms, called facultative, genetic research and field evaluation were taken on four spring cultivars: Tybalt (NL), Monsun (DE), Ostka Smolicka (PL) and Bombona (PL), currently being recommended by breeders. The PPD gene analyze, expression level of dehydrine genes (WCS120 and WDHN13) in cooling test, and qPCR for RNA isolation and analyses of WCS120 and WDHN13 gene expression at the BBCH12 stage of wheat were estimated. Molecular analysis of PPD-D1 gene confirmed the presence of photoperiod sensitive allele ppd-D1b in all tested genotypes. The highest level of NRE WCS120 gene was detected in cultivars Tybalt and Bombona. Two-year field experimental study assessed the growth, development and productivity of facultative and spring crops of studied cultivars. Based on our results from field experiments and result of molecular analysis of alleles of PPD-D1 gene, the tested genotypes can be considered as potentially facultative genotypes.  相似文献   
95.
Diabetes is characterized by an absolute or relative deficiency in β-cell mass, which cannot be reversed with existing therapeutic strategies. The restoration of the endogenous islet β-cells can stabilize the level of blood glucose. The islet β-cells can be obtained from the directional differentiation of stem cells, but the process is complex and has the risk of teratomas generation. Cell direct reprogramming, one terminal differentiated cell can transdifferentiate into another kind of terminal differentiated cell, which is other than directional differentiation from stem cells. Direct reprogramming gives rise to the generation of islet β-cells from one terminal differentiated cell, may be preferable for diabetes therapy because of its unique advantage.  相似文献   
96.
吴慧娟  刘艳  王锡锋 《中国农业科学》2017,50(17):3337-3343
【目的】由异沙叶蝉(Psammotettix alienus)传播的小麦矮缩病毒病是近年来中国西北部麦区严重发生的小麦病毒病害之一。受侵染的小麦植株严重矮化,有效分蘖减少,产量损失严重。论文旨在明确小麦矮缩病毒(Wheat dwarf virus,WDV)侵染小麦植株后矮化症状形成与赤霉素代谢调控的关系,为该病害的防治打下基础。【方法】以小麦品种扬麦12为试验材料,以异沙叶蝉为传毒介体饲毒后转移到1叶期的健康幼苗(3头/株)上进行传毒,同时以无毒异沙叶蝉取食健康幼苗为对照。根据试验需要,不同时间取样备用。为保证试验的准确性,经PCR检测为阳性的作为处理组试验材料;采用间接酶联免疫吸附(ELISA)法,利用植物赤霉素(GA3)试剂盒测定分析侵染第21天取样的小麦叶片赤霉素含量;将带毒条沙叶蝉接种的小麦苗分为两个平行处理组,接种后第7天分别用GA3(浓度为50 mg·L-1)和H2O进行叶面喷施处理,每隔一周处理一次。以无毒叶蝉接种后长势一致的小麦苗作为对照组,根据株高统计结果分析外施赤霉素对受侵染小麦植株的表型变化;以山羊草(Aegilops tauschii)的内根-贝壳杉烯合成酶(ent-kaurene synthase-like 3,KSL3)的基因编码区序列为参考基因设计引物(KSL3-F:5′-ATGATGGTGAATCCGCCGC-3′;KSL3-R:5′-TTAATGGTTGATCTTTGTTT-3′),对扬麦12的KSL3进行克隆和序列分析;分别取接种后7、14和21 d的小麦植株叶片,提取RNA后反转录,以克隆得到的Ta KSL3基因序列设计引物(Ta KSL3-F:5′-GAGACATGTGCCATGGCGTTC-3′;Ta KSL3-R:5′-CGTGTCACTCAGATCGGTGGAG-3′),选择小麦翻译延伸因子1A(EF-1α)作为内参基因,利用荧光定量PCR方法分析赤霉素代谢相关基因的转录水平。【结果】经ELISA检测发现,接种21 d的发病植株赤霉素含量与健康植株相比降低了28.9%;通过施用浓度为50 mg·L-1的赤霉素后,发病植株的平均株高相比对照组显著增加35.9%;采用同源克隆得到了完整的小麦赤霉素合成途径关键酶KSL3的编码区序列,长度为1 827 bp,编码608个氨基酸,BLAST比对分析发现该DNA序列与山羊草KSL3编码区序列相似度为85.2%。经荧光定量检测发现受小麦矮缩病毒侵染后小麦KSL3表达量显著下降,接种14 d降低为对照组的35.7%,21 d降低为对照组的9.6%。【结论】小麦矮缩病毒的侵染导致赤霉素合成途径关键酶的表达量降低,可能使赤霉素合成受阻,赤霉素含量降低引发受赤霉素调节的细胞生物学过程异常,从而诱导矮化症状形成。研究结果为揭示小麦矮缩病毒侵染的致病机理和病害防控打下了基础。  相似文献   
97.
为探究氮素形态对菠菜生长和品质的影响,试验采用盆钵培养的方法,在总氮浓度为15 mmol/L的条件下,设置了5种NO_3~--N与NH_4~+-N配比(分别为100:0、75:25、50:50、25:75和0:100),测定了5种铵硝配比条件下菠菜生长与品质相关指标。结果表明:与NH_4~+-N相比,NO_3~--N更有利于菠菜生长与Vc积累。适当增加NH_4~+-N比例后,Vc含量虽显著降低,但对菠菜的生长却无显著影响,并可显著降低可食用部分硝酸盐含量。因此,为了提供高产、低硝酸盐的优质菠菜,笔者认为适宜的NO_3~--N?NH_4~+-N为50:50。  相似文献   
98.
AIM: To investigate the effects of dexmedetomidine (DEX) on acute alcoholic hepatic injury in mice and to explore the possible mechanisms. METHODS: Kunming mice (n=50) were randomly divided into 5 groups (n=10): normal saline control (NS) group, acute alcoholic hepatic injury model (E) group, low-dose (10 μg/kg) DEX (E+L) group, medium-dose (50 μg/kg) DEX (E+M) group and high-dose (100 μg/kg) DEX (E+H) group. The animals were sacrificed at 6 h after gavage of alcohol or normal saline. The levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), triglyceride (TG), malondialdehyde (MDA), glutathione (GSH) and superoxide dismutase (SOD) were measured. The livers were removed for evaluation of histological characteristics and determining the content of tumor necrosis factor-α (TNF-α) amd interleukin-1β (IL-1β) in the liver tissues by ELISA. The expression levels of cytochrome P450 2E1 (CYP2E1) and nuclear factor-κB (NF-κB) in the liver tissues were evaluated by Western blot. RESULTS: Compared with NS group, the levels of ALT, AST and TG were obviously increased in E group, which were obviously decreased in E+M and E+H groups. Compared with NS group, the levels of TNF-α, IL-1β and MDA were obviously increase in E group, which were obviously decreased in E+M and E+H groups. Compared with NS group, the activity of SOD and the content of GSH were obviously decreased in E group, which were obviously increased in E+M and E+H groups. Compared with NS group, the expression of CYP2E1 and NF-κB was obviously increase in E group, which was obviously decreased in E+M and E+H groups. Compared with NS group, ethanol induced marked liver histological injury, which was less pronounced in E+M and E+H groups. CONCLUSION: DEX has a protective effect on mouse liver with acute alcoholic injury by the involvement in the processes of antioxidation and antiinflammation, and its mechanism may be associated with the inhibition of CYP2E1 and NF-κB expression.  相似文献   
99.
AIM: To explore the clinical significance of Krüpple-like factor 15 (KLF15) protein expression in the patients with lung adenocarcinoma for exploring the therapeutic and prognositic biomarkers of lung cancer. METHODS: Four cases of lung adenocarcinoma tissues and matched adjacent tissues were collected from our hospital, and the expression of KLF15 protein in these tissues was analyzed by Western blot. At the same time, 72 cases of archived paraffin-embedded samples and clinical data of the patients with lung adenocarcinoma were also collected. The KLF15 protein expression in the archived paraffin-embedded lung adenocarcinoma samples was detected by immunohistochemical staining. The correlations between KLF15 protein expression and clinical characteristics of the patients including prognosis were also analyzed. In addition, the KLF15 protein was up-regulated in A549 cells, and then the effects of KLF15 protein on the viability of the cells were measured by CCK-8 assay. RESULTS: The protein expression of KLF15 in the 4 cases of lung adenocarcinoma tissues was significantly lower than that in matched paracancerous tissues. Fifty-three cases of lung adenocarcinoma specimens showed low expression or no expression of KLF15 protein in total 72 cases (73.6%). The 5-year survival rate of the patients with high expression of KLF15 protein in their specimens was higher than that of the patients with the low expression of KLF15 protein (P<0.01), and the expression of KLF15 protein was significantly correlated with the pathological staging (P<0.01) and T stage (P<0.01) of the patients with lung adenocarcinoma. Furthermore, the low expression of KLF15 protein was an important poor prognostic indicator of the patients. Up-regulation of KLF15 protein in the A549 cells significantly inhibited the growth of the cells. CONCLUSION: KLF15 inhibits the growth of lung adenocarcinoma cells. It could be used as a therapeutic target and a prognostic biomarker for the patients with lung adenocarcinoma.  相似文献   
100.
为研究运输方式对生菜采后生理及保鲜效果的影响,以‘橡生2号’生菜为研究对象,选择3种常见的运输方式:保温箱包装常温运输(A)、保温箱加制冷剂包装在常温下运输(B)、PE包装袋加纸箱包装在0℃下运输(C)进行试验。结果表明,采用C方式在0℃冷藏条件下运输的生菜,其失重率和呼吸强度均低于另外2组,VC含量和感官评价高于另外2组。因此在运输时间在12 h内可以采用A方式运输,在24 h内可以采用B方式运输,如超过24 h则最好使用C方式运输来保证生菜的货架期及品质。  相似文献   
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