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1.
Sung Ho Son Sung Mee Choi Kum Boo Choi Yun Hee Lee Dea Sook Lee Myung Suk Choi Young Goo Park 《Biotechnology and Bioprocess Engineering》1999,4(2):112-118
Calli were induced from 300,000 embryos isolated from immature to mature stage of seeds collected on late September from 14
elite trees. When the embryos were cultured onto plastic Petri-dish containing 20 mL of modified B5 basal medium supplemented
with 3% (w/v) sucrose, 500 mg/L casein hydrolysate, 250 mg/L myo-inositol, 0.5% (w/v) polyvinyl polypyrrolidon (PVPP), 2×MS
vitamins, 0.5 mg/L gibberellic acid, and 10 mg/L 2,4-D after 2 weeks of culture, yellowish-white calli were immediately formed
on the surfaces of embryos, and subcultured for 4 weeks in same culture medium. Because most of calli maintained for more
than 3 months were revealed differences in their colors, surface texture, and growth rate, visual selection was made for first
round screening. When the size of visually selected calli larger than 19 mm in their diameter were inoculated, persistent
proliferation was observed. Among the plating methods tested for the selection of rapid growing cell lines at single cell
and/or small cell aggregate level, 2-layer spread plating revealed as the best for single cell cloning. To enhance cell growth
and maintain high rate of viability for long-term culture of yew cells in bioreactor, final cell volume less than 50% in SCV
seemed to be the best. Time course study revealed that 30% of inoculum density was suitable for fed batch culture. Among the
tested conditional media, the rate of 1∶2 (old medium: fresh medium) was recorded at the best for cell growth. 相似文献
2.
刺激家兔颈交感神经对颈动脉窦反射的影响 总被引:2,自引:0,他引:2
在36只麻醉家兔观察了电刺激颈交感神经(CSN)对颈动脉窦压力感受器(CSB)活动的影响。所得结果如下:(1)电刺激 CSN 可使夹闭颈动脉引起的加压反射消失或倒转,△BP 从刺激前的 39.5±3.6mmHg 变为刺激时的-0.31±5.4mmHg(P<0.001)。(2)在电刺激CSN 时,静注新福林所诱发的颈动脉窦压力感受器-心率反射增强,表现为反射性心率减慢较刺激前更为明显。(3)在以50—200mmHg 的压力充胀两侧颈动脉窦的条件下,刺激 CSN 引起窦内压与平均动脉压的关系曲线下移,与刺激前曲线相比有明显差异(P<0.01)。(4)切断 CSN 后,动脉血压有所升高,提示 CSN 对 CSB 活动有紧张性调节作用。以上结果比较明确地表明家兔 CSN 对 CSB 活动有调节作用。此作用可能是 CSN 作用于窦壁平滑肌而间接引起的。 相似文献
3.
Net Accumulation of Minerals and Water and the Carbon Budget in an Expanding Leaf of Tomato 总被引:2,自引:0,他引:2
The changes in f. wt, d. wt, nitrogen, potassium, calcium, phosphorus,magnesium and carbon of the seventh leaf of a tomato plant weremeasured at seven occasions from 10 days to 30 days after leafemergence. Measurements of CO2 exchange by the leaf during bothlight (70 W m2, 7 h) and dark (17 h) periods and thechange in carbon content over these two periods enabled a carbonbalance to be constructed on these seven occasions. Changesin the sugars and starch contents of the leaf over these twoperiods at each occasion were measured. With the exception of calcium the rates of accumulation of allsubstances increased to their maxima when the leaf was 2224-days-old.Carbon fixation per unit f. wt. increased to a maximum whenthe leaf was 16-days-old. In a 10-day-old leaf the rate of carbonfixation was already four-fifths of maximum and one-quartermore than that at 30 days. The rate of night respiratory lossof carbon per unit fresh weight decreased as the leaf expanded.In a 10-day-old leaf, the amount of carbon lost by night respirationaccounted for one-quarter of that fixed in the same day. Thisfraction fell to one-tenth when the leaf was 22-days-old andremained constant thereafter. The amount of carbon being importedto the leaflets of a 10-day-old leaf was less than one-quarterof that accumulated in 1 day. Thus, the contribution of theimported carbon to the leaf growth up to this stage is relativelysmall. The transition of the seventh leaf from being a net importerto being a net exporter occurred when the leaf was 13-days-old. The sucrose content per unit f. wt was higher in the youngerthan in the older leaves and was not correlated to the transitionfrom net import to net export. The accumulation and breakdownof starch in a leaf were related not only to the growth of theleaf but also to the development of the whole plant. Lycopersicon esculentum, tomato, leaf, accumulation of minerals, water content, carbon budget 相似文献
4.
夜蛾趋光特性的研究:复眼转化过程中的行为变异 总被引:17,自引:5,他引:12
影响蛾类趋光性和灯光诱蛾效果的因素很多。过去,国内外许多观察和实验都侧重在研究光源的辐射光谱和辐射强度以及气候条件的影响。至于蛾类的主要感光器官的适应状态怎样影响趋光性,却极少引起注意。 陈元光等(1963)曾经用电生理学的方法,测出粘虫蛾复眼的暗适应过程大约为30—45分钟。Agee(1972)用电生理方法研究复眼,发现美国棉铃虫复眼在暗适应中,达到最高灵敏度的时间为30分至285分,雌、雄的平均时间分别为88分和115分;美国烟青虫雌、雄蛾的平均时间分别为119分和121分。最近,李典谟等(1977)以复眼反射光的增强作为暗适应的指标,测出烟青虫蛾在暗室内暗适应时,复眼的转化速率很不一致。快的个体约经过1小时就达到最大反射值;慢的个体则需经过3小时,而绝大多数个体(79%)则在1—2(1/2)小时内。因此,他们推测在入夜后的一段时间里,田间昆虫的眼由昼眼转化为夜眼的情况是各不相同的,并且认为这种差异会影响成虫对于灯光发生不同的行为反应。棉铃虫(Heliothis armigera)蛾是灯光防治的主要对象之一,为了进一步探索这个问题,我们认为有必要检查一下在日夜交替的自然暗适应条件下其复眼状态究竟是否一致,复眼状态怎样影响着趋光性,以便深入地了解夜蛾类趋光性的控制因素。 相似文献
5.
Cozijnsen L. Braam R. L. Bakker-de Boo M. Otten A. M. Post J. G. Schermer T. Bouma B. J. Mulder B. J. M. 《Netherlands heart journal》2022,30(4):207-211
Netherlands Heart Journal - To determine the prevalence of undiagnosed bicuspid aortic valve (BAV) and isolated aortic dilatation in first-degree relatives (FDRs) of patients with isolated BAV and... 相似文献
6.
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8.
L. Cozijnsen M. Bakker-de Boo J. J. Kardux B. J. Bouma 《Netherlands heart journal》2013,21(12):561-564
We report a case of a 64 year old woman with a calcified ring at the level of the sinotubular junction. Echocardiography and Computed Tomography showed a supravalvular aortic stenosis, without known associated lesions, except for the existence of an aberrant right subclavian artery. These combination of abnormalities makes it an unique case. Differential diagnosis of sinutubular calcification is added. From the literature a short review of supravalvular aortic stenosis is presented with indications for surgical intervention. Lifelong and regular follow up is necessary. 相似文献
9.
Ip Yuen K. Hiong Kum C. Teng Joey H. Q. Boo Mel V. Choo Celine Y. L. Wong Wai P. Chew Shit F. 《Coral reefs (Online)》2020,39(2):451-465
Coral Reefs - Giant clams flourish in nutrient-poor waters of tropical Indo-Pacific because they live in symbiosis with extracellular dinoflagellates (zooxanthellae) and receive photosynthates from... 相似文献
10.
Ga Hun Boo Ying‐Xiong Qiu Jung Yeon Kim Put O. Ang Samuel Bosch Olivier De Clerck Peimin He Atsushi Higa Bangqin Huang Kazuhiro Kogame Shao‐Lun Liu Tu van Nguyen Shoichiro Suda Ryuta Terada Kathy Ann Miller Sung Min Boo 《Journal of phycology》2019,55(6):1319-1334
The evolutionary and population demographic history of marine red algae in East Asia is poorly understood. Here, we reconstructed the phylogeographies of two upper intertidal species endemic to East Asia, Gelidiophycus divaricatus and G. freshwateri. Phylogenetic and phylogeographic inferences of 393 mitochondrial cox1, 128 plastid rbcL, and 342 nuclear ITS2 sequences were complemented with ecological niche models. Gelidiophycus divaricatus, a southern species adapted to warm water, is characterized by a high genetic diversity and a strong geographical population structure, characteristic of stable population sizes and sudden reduction to recent expansion. In contrast, G. freshwateri, a northern species adapted to cold temperate conditions, is genetically relatively homogeneous with a shallow population structure resulting from steady population growth and recent equilibrium. The overlap zone of the two species roughly matches summer and winter isotherms, indicating that surface seawater temperature is a key feature influencing species range. Unidirectional genetic introgression was detected at two sites on Jeju Island where G. divaricatus was rare while G. freshwateri was common, suggesting the occurrence of asymmetric natural hybrids, a rarely reported event for rhodophytes. Our results illustrate that Quaternary climate oscillations have left strong imprints on the current day genetic structure and highlight the importance of seawater temperature and sea level change in driving speciation in upper intertidal seaweed species. 相似文献