高温胁迫对国稻6号开花结实习性的影响   总被引：8，自引：0，他引：8  

陶龙兴  谈惠娟  王熹  曹立勇  宋建  程式华 《作物学报》2008,34(4):669-674

为研究杂交稻对开花结实期高温胁迫的生理生态适应性, 选用具代表性的主栽杂交稻组合国稻6号、两优培九等, 人工设计极值高温40℃, 自始穗后第15天每天6 h进行热害处理, 以自然气候条件为对照, 测评结实的热害指数, 并从中选择对开花结实期高温胁迫反应差异较大的国稻6号与协优46, 观察高温胁迫对其开花结实习性的影响。结果表明, 国稻6号具较高耐热性似与其“被动避热”适应性有关, 主要表现在开花结实习性的变化, 首先是花期缩短, 花期集中, “粒间顶端优势”有所减弱; 其次是花时分散, 开花峰期峰值下降, 虽未见花时提前, 但见日初花量增加与花时向后延长2 h。  相似文献   

Daily rhythmicity in nutrient content of asinine milk   总被引：2，自引：0，他引：2  

G. Piccione  F. Fazio  G. Caola  R. Refinetti   《Livestock Science》2008,116(1-3):323-327

Asinine (donkey) milk has been proposed as an alternative to bovine (cow) milk for consumption by human infants who are allergic to bovine milk proteins. To expand the current knowledge of asinine lactation, we investigated daily rhythmicity in the concentration of major constituents of asinine milk. We observed no daily rhythmicity in somatic cell count and pH but observed robust rhythmicity in lipid, lactose, and protein content (robustness greater than 70%, p < 0.01). Lipid and lactose content peaked during the night, whereas protein content peaked during the day. Lipid content of asinine milk was lower than that of human milk, and asinine milk resembled human milk better than bovine milk regarding sugar and protein content.  相似文献   

Effects of sun compass error on spatial search by Clark's nutcrackers     

Debbie M. KELLY  Ken CHENG  Russell BALDA  Alan C. KAMIL 《Integrative zoology》2019,14(2):172-181

Animals employ compasses during navigation, but little attention has been paid to how accuracy is maintained in the face of compass error, which is inevitable in biological systems. The use of multiple landmarks may minimize the effect of compass error. We allowed Clark's nutcrackers to cache seeds in an outdoor aviary with either one or four landmarks present, and subsequently subjected them to small clock‐shifts mimicking the effects of compass error. As predicted, the results showed a significant decrease in search accuracy following the clock‐shift when one landmark was present but not when four landmarks were present. These results support that nutcrackers encode information from the sun as well as terrestrial landmarks, and these spatial cues are used in a flexible manner. Overall, our results are important as they support the hypothesis that multiple landmarks may be used during situations where the sun compass has even a small amount of error.  相似文献   

AWGN信道下小波多速率调制的时钟提取     

黄国庆  陶祁 《信阳农业高等专科学校学报》2009,19(1)

为解决极值点抖动和假同步问题,首先在分析AWGN信道下小波多速率调制最佳接收的基础上,应用单子带上的最大似然估计方法,提出了改进的同步时钟提取算法,不仅能准确估计小波相位延时,而且可以校正收发时钟的频率偏差。在此基础上,对相位误差函数进行了重新定义,并分析了它在抗假同步和提高稳定性上所作的改进。仿真结果表明,该算法具有快速、稳定的收敛性能和随尺度增大而逐级优化的误码性能。  相似文献   

Rapamycin improves circadian rhythm disorder induced by Aβ31-35 in mice     

WANG Chang-tu  ZHANG Rui  YUAN Yuan  ZHAO Jin  REN Ya-nan  WANG Li  WANG Xiao-hui 《园艺学报》2019,35(4):653-659

AIM:To observe the effect of rapamycin (Rapa) on the circadian rhythm disorder in C57BL/6 mice and the abnormal expression of Per2 in mouse hippocampal neuronal cell line HT22 induced by amyloid β-protein 31-35 (Aβ31-35).METHODS:The 6~8-week-old male C57BL/6 mice were selected for wheel-running behavior experiment. The effect of Rapa on the circadian rhythm disorder induced by Aβ31-35 was analyzed. The HT22 cells were randomly divided into control group, Aβ31-35 group, Rapa+Aβ31-35 group and Rapa group. The cell viability was measured by CCK-8 assay. Real-time PCR was used to detect the mRNA expression of Per2, and Western blot was applied to examine the expression of Per2 protein at circadian time (CT) 16. RESULTS:Compared with control group, Aβ31-35 disturbed the circadian rhythm which exhibited significantly longer free running period. However, the disruption was significantly relieved by pretreatment with Rapa compared with Aβ31-35 treatment, which manifested significantly decreased free running period (P<0.05). Aβ31-35 decreased the viability of HT22 cells compared with control group, and Rapa pretreatment reduced the toxicity of Aβ31-35 through up-regulating the cell viability. Abnormal mRNA expressions of Per2 was induced by Aβ31-35 in the HT22 cells. Rapa pretreatment reversed the abnormal expression of Per2 at mRNA level induced by Aβ31-35. Aβ31-35 significantly decreased the protein expression of Per2 at CT16. Pretreatment with Rapa significantly improved the protein expression of Per2. CONCLUSION:Rapa attenuates the circadian rhythm disorder induced by Aβ31-35 in C57BL/6 mice, and improves the abnormal expression of Per2 induced by Aβ31-35 in HT22 cells.  相似文献   

利用酵母双杂交系统筛选玉米ZmPRR73的互作蛋白          下载免费PDF全文

王盼盼  王雷立  张严玲  刘青青  董柯清  李安然  王翠玲 《西北农业学报》2024,(3):416-525

为了阐明ZmPRR73基因的生物学功能,构建诱饵表达载体pGBKT7-ZmPRR73，利用酵母双杂交技术，从长日照光照环境诱导的热带玉米自交系的cDNA文库中筛选与ZmPRR73互作的蛋白。结果显示：构建的诱饵载体pGBKT7-ZmPRR73对酵母菌株无毒性，且对报告基因无自激活活性，共鉴定出12个与ZmPRR73互作的候选蛋白。生物信息学分析表明，这些候选互作蛋白的功能涉及植物的转录调控、离子跨膜转运的调节、信号转导、电子传递链等多个方面，推测ZmPRR73蛋白与以上蛋白互作参与多个信号转导和代谢途径，研究结果补充和完善了ZmPRR73蛋白参与的调控途径，为进一步研究生物钟核心元件ZmPRR73的分子功能提供了新的分子证据。  相似文献   

Daily Rhythms of Left Atrial Pressure in Beagle Dogs with Mitral Valve Regurgitation     

T. Ishikawa  R. Tanaka  S. Suzuki  Y. Saida  A. Soda  R. Fukushima  Y. Yamane 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2009,23(4):824-831

Background: Mitral valve regurgitation (MR) causes increased left atrial pressure (LAP) and is associated with occurrence of clinical signs. It will be useful to understand diurnal variations of LAP for the management of MR.
Hypothesis: Circulatory parameters and diurnal rhythm are linked to clinical signs in cardiac diseases. LAP also exhibits a diurnal rhythm in dogs with MR.
Animals: Five healthy Beagle dogs weighing 9.8–12.8 kg (3 males and 2 females; aged 2 years) were used.
Methods: A radiotelemetry system for continuous measurement of LAP was used in this study. Rupture of the chordae tendineae was experimentally induced via left atriotomy, and a transmitter catheter was inserted into the left atrium. The body of the transmitter was implanted SC. After clinical condition was stabilized, the severity of MR was evaluated by echocardiography, and LAP was recorded for 72 consecutive hours for the analysis of diurnal variation.
Results: Abrupt increases in LAP, which averaged 16.7 mmHg, were observed at feeding periods. In contrast, strong diurnal LAP variations were found, with a significant but slight increase in daytime LAP compared with nighttime LAP.
Conclusions and Clinical Importance: Diurnal LAP is characterized by a slight but significant nocturnal decrease and abrupt increases in response to excitation. The latter seemed to be more important considering the relationship with clinical manifestations. The clinical relevance of exercise restriction in the management of MR was acknowledged.  相似文献   

Clock genes and cardiovascular diseases     

XU Chen  QIAN Rui-zhe  JIN Hui-ming 《园艺学报》2006,22(7):1450-1453

The biorhythms of every species are precisely regulated to adapt the environmental changes. The function of biorhythms is controlled by the clock genes in either a single cell or the whole body. The function of clock genes depends on the feedback circles that are composed by the interactions among the clock components. Many studies indicate that circadian clock is closely related to diseases. Several cardiovascular diseases such as myocardial ischemia and myocardial infarction show overt circadian rhythms, indicating that clock genes may play an important role in such kinds of diseases.  相似文献   

Comparative analysis of the daytime and nighttime brain transcriptomes of Pelteobagrus vachellii     

Jiaxian Sun  Chuanjie Qin  Jiang Xie  Yongwang Han  Yongfu Liu  Qinchao Shi  Yunyun Lv 《Aquaculture Research》2020,51(7):2842-2851

  相似文献   

不同发育阶段草鱼消化酶活力的变化及其昼夜节律   总被引：2，自引：0，他引：2  

曹香林  郭蓓  彭墨  闫金鹏  董殊君  陈军用  聂国兴 《河南农业科学》2009,(7)

以草鱼为对象,研究了不同发育阶段的消化酶活力及其昼夜变化规律。结果表明:60d组的草鱼肝胰脏及前、中、后肠消化酶活力高于30d组和150d组的;肝胰脏及前、中、后肠蛋白酶活力的峰值分别出现在17:00(1:00)、17:00、1:00、1:00;淀粉酶活力的峰值分别出现在13:00、17:00(5:00)、21:00、21:00(5:00);脂肪酶活力的峰值分别出现在17:00、17:00、17:00、17:00(1:00)。因此认为,草鱼消化酶活力与草鱼生长发育阶段密切相关,具有组织差异性,且呈现明显的昼夜节律。  相似文献