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951.
GU  AI XIA  SHEN  SHU XING  WANG  YAN HUA  ZHAO  JIAN JUN  XUAN  SHU XIN  CHEN  XUE PING  LI  XIAO FENG  LUO  SHUANG XIA  ZHAO  YU JING 《Journal of genetics》2015,94(3):435-444
Journal of Genetics - Five monosomic alien addition lines (MAALs) of Brassica rapa ssp. pekinensis – B. oleracea var. capitata were obtained by hybridization and backcrossing between B. rapa...  相似文献   
952.
Brassinosteroids (BRs) are essential for plant growth and development; however, their roles in the regulation of stomatal opening or closure remain obscure. Here, the mechanism underlying BR‐induced stomatal movements is studied. The effects of 24‐epibrassinolide (EBR) on the stomatal apertures of tomato (Solanum lycopersicum) were measured by light microscopy using epidermal strips of wild type (WT), the abscisic acid (ABA)‐deficient notabilis (not) mutant, and plants silenced for SlBRI1, SlRBOH1 and SlGSH1. EBR induced stomatal opening within an appropriate range of concentrations, whereas high concentrations of EBR induced stomatal closure. EBR‐induced stomatal movements were closely related to dynamic changes in H2O2 and redox status in guard cells. The stomata of SlRBOH1‐silenced plants showed a significant loss of sensitivity to EBR. However, ABA deficiency abolished EBR‐induced stomatal closure but did not affect EBR‐induced stomatal opening. Silencing of SlGSH1, the critical gene involved in glutathione biosynthesis, disrupted glutathione redox homeostasis and abolished EBR‐induced stomatal opening. The results suggest that transient H2O2 production is essential for poising the cellular redox status of glutathione, which plays an important role in BR‐induced stomatal opening. However, a prolonged increase in H2O2 facilitated ABA signalling and stomatal closure.  相似文献   
953.
Self-directed behavior(SDB) is characterized as an indicator of anxiety, frustration and stress in nonhuman primates. In this study, we collected self-directed behavior data from one group of free-ranging Tibetan macaques(Macaca thibetana) at Mt. Huangshan, China(September 2012–May 2013) using a combination of behavioral sampling methods including focal animal sampling, behavioral sampling, continuous sampling and instantaneous sampling. Our results showed that females engaged in significantly higher rates of self-directed behavior when they were in proximity to dominant individuals compared to subordinate ones. Conflict losers significantly increased their SDB rates after agonistic episodes, indicating that SDB might also serve as an index of anxiety in M. thibetana. We further found that females significantly increased their SDB rates when focal individual was proximity to weakly affiliation relationship higher rank members than to strongly affiliation relationship higher rank members. If conflicts were not reconciled, the postconflict SDB rates of losers were higher when they stayed with strongly affiliation opponents; if conflicts were reconciled, victims of strongly affiliation relationships opponents engaged in more SDB rates before reconciliation than after reconciliation, while victims of moderately affiliation relationships opponents did not engaged in more SDB rates before reconciliation than after reconciliation. We conclude that both of dominance rank and affiliation relationships might both influence the SDB rates of female Tibetan macaques significantly, suggesting that SDB is not only an index of anxiety in Tibetan macaques, but also can provide a new insight into evaluation of social relationships between individuals.  相似文献   
954.
2011年10月—2012年7月对渔山列岛浮游动物的种类组成、优势种、群落结构、丰度和生物量进行了调查,分析了浮游动物丰度、多样性指数及其与环境因子的相关性。调查共鉴定浮游动物8类45种,其中原生动物类14种,占31.1%;桡足类次之13种,占28.9%。主要优势种有中华哲水蚤(Calanussinicus)、根状拟铃虫(Tintin—nopsisradix)和桡足类幼虫(Copepoditenauplinua)。多样性指数(H')7月(3.324)最高,10月(2.988)最低。结合多样性指数及丰富度指数可见,调查期间渔山列岛浮游动物的生物多样性7月最高,物种较丰富。相关性分析表明,浮游动物群落分布与营养盐、水温、盐度等环境因子存在一定的相关性。  相似文献   
955.
目的:在冷暴露实验动物模型上,评价盐酸哌唑嗪(Pra)和消旋山莨菪碱(Ani)对大鼠、小鼠肢端皮肤温度的调节作用。方法:将80只大鼠随机分为8组,室温下灌胃给药,60 min后放入指定温度(5℃、18℃)环境中冷暴露,并于给药后180 min和300 min使用红外摄像仪测定实验动物尾部近心端1/3处的皮肤温度,观察皮肤温度的变化,评价药效。结果:单独使用Pra对大鼠肢端皮肤温度无影响,对小鼠肢端皮肤温度提高效果较差;而单独使用Ani对大鼠和小鼠肢端皮肤温度均无提高作用;两药联用后实验动物尾温得到显著提高,且具有一定剂量依赖性。结论:Pra和Ani联用能有效提高冷暴露大鼠、小鼠的肢端皮肤温度,并且不会降低体心温度。  相似文献   
956.
目的:通过观察分析正常人左室等容舒张期内的结构和血流变化,明确其各时相及相应的时间周期,为应用心脏同步化治疗提供依据。方法:选取60例健康体检者,通过常规二维左心室血流脉冲多普勒(PW)和组织多普勒(TDI)检查,录取左心室PW、TDI和双声道超声心动图(DCE)图像,将所有受检者等容舒张时间(WRT)分为等容舒张早期(IVRTe)和等容舒张后期(IVRTl)并测量各时相时间间期,测量指标包括:①等容舒张期时间间期(IVRT);②等容舒张早期时间间期(IVRTe);③等容舒张后期时间间期(IVRTl);④IVRTl/IVRT;并计算心率校正后数值:⑤cfVRT;⑥cIVRTe;⑦cIVRTl;⑧cIVRTl/clVRT;⑨测量DCE上二尖瓣血流变化与组织运动时间差(TE-6)。结果:观察分析入选的45例图像,PW曲线上均观测到IVRT内i波存在,i波约占IVRT的1/2,平均值为(49.17±5.37)ms,以i波下降支转折点为t点,可将IVRT划分为IVRTe和IVRTl。84%TDI曲线上观测到IVRT内j波存在,j波约占IVRT的1/2,平均值为(43.13±4.83)ms,以j波形成点为t点,可将IVRT划分为IVRTe和IVRTl。PW、TDI、DCE三组测量指标进行比较,仅有常规PW与TDI所测量的IVRT、IVRTe、IVRTl数值有统计学差异(P〈0.05);常规PW和TDI测量数值分别与DCE所测数值比较,均无统计学差异。校正心率后,三组之间两两比较,其所测数值差异均无统计学意义。三组所测IVRTl/IVRT、cIVRTl/cIVRT差异均无统计学意义,所测数值的平均值为(0.50±0.12)ms。经重复性检验证实.DCE测量IVRT各时相时间间期的测量误差较小,有较好的一致性。结论:研究发现IVRT可进一步划分为两个时相即IVRTe和IVRTl,IVRTe内有i波存在,IVRTl内有i波存在,划分点t点大致为IVRT中点。  相似文献   
957.
The Asian corn borer Ostrinia furnacalis (Guenée) enters facultative diapause as fully‐developed larvae in response to short‐day conditions. As a consequence of geographical variation in photoperiodic response, moths from Nanchang (28°46′N, 115°50′E) enter diapause in response to short day‐lengths (D strain), even at the high temperatures whereas moths from Ledong (18°47′N, 108°89′E) exhibit almost no diapause under the same conditions (N strain). In the present study, crosses between the two strains are used to evaluate the inheritance of diapause under different photoperiods at temperatures of 22, 25 and 28 °C. The moths, both reciprocal crosses and backcrosses, show a clear long‐day response, similar to that of the D strain, suggesting that the photoperiodic response controlling diapause in this moth is heritable. However, the critical day‐length for induction of diapause is shorter in hybrids than in the D strain. The N strain also shows a short‐day photoperiodic response at the lower temperature of 22 °C, indicating that the N strain still has the capacity to enter a photoperiodically‐induced diapause, depending on the rearing temperature. The incidence of diapause in all crosses is highest with D strain fathers or grandfathers and lowest with N strain fathers or grandfathers, indicating that the male parent has significantly more influence on the incidence of diapause of subsequent progeny than the female. The results obtained from all crosses under LD 12 : 12 h or LD 13 : 11 h photocycles at 25 °C show that inheritance of diapause in O. furnacalis does not fit an additive hypothesis and that the capacity for diapause is transmitted genetically in the manner of incomplete dominance.  相似文献   
958.
油菜BnMKK4全长基因的克隆及表达分析   总被引:2,自引:0,他引:2  
从‘陇油6号’油菜中克隆得到了一个新的BnMKK4基因的cDNA,全长1317bp,其中包括993bp的开放阅读框,159bp的5’非翻译区(5^1UTR),165bp的3。非翻译区(3’UTR)。与拟南芥AtMKK4有很高的同源性,因此命名为BnMKK4(GenBank登录号JF268686)。该基因编码330个氨基酸的蛋白质,分子量36.5kDa,等电点为9.01。实时荧光定量PCR结果显示该基因表达受低温胁迫和盐胁迫的诱导,表明该基因在油菜适应低温胁迫和盐胁迫的过程中发挥作用。  相似文献   
959.
在昆虫中,雄虫先于雌虫羽化,称为雄虫先熟现象,而雌虫先于雄虫羽化,称为雌虫先熟现象。前者最为普遍,后者报道较少。本试验在20、22和25℃下对棉铃虫Helicoverpa armigera(Hilbner)的生长发育进行了详细的研究。结果显示发育历期随温度的升高而缩短,雌雄间发育历期有着显著的差异,各个温度下雌虫均比雄虫先羽化,表明棉铃虫属于雌性先熟种类,而这种差异主要是由于雌虫的蛹期较短所致。幼虫发育历期与蛹重呈显著的正相关性。  相似文献   
960.
目的:分析miR-200a及AFP在肝癌、肝硬化患者血清中的表达水平并进行比较,探索其成为肝癌早期诊断血清标志物的可能性。方法:临床收集肝正常、肝硬化、肝癌患者血液标本。运用实时定量PCR技术检测血清miR-200a的相对表达情况,血清AFP水平从临床资料中提取。结果:临床标本分析结果显示,miR-200a在肝硬化及肝癌患者中均显著下调(P<0.05),AFP仅在肝癌患者中出现异常表达。结论:血清miR-200a极大程度地参与了肝癌发生,对肝硬化及肝癌具有一定的诊断价值。  相似文献   
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