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Abstract Morphological features of mature larvae of Petelia rivulosa (Butler), Exangerona prattiaria (Leech) and Culcula panterinaria (Bremer & Grey) of Ennominae are described and illustrated. All specimens examined are deposited in the Insect Collection of Department of Forest Resources Protection, Kangwon National University, Korea. 相似文献
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<正> 1980年,Hunter首次发现Rous肉瘤病毒转化的细胞,其蛋白质分子上的酪氨酸残基磷酸化水平明显升高。现已知道,其它的肿瘤病毒诱导的转化细胞以及某些恶性肿瘤细胞的酪氨酸残基磷酸化作用亦有不同程度的增强。但迄今物理的致癌因素如放射性同位素引起的细胞转化是否伴随着酪氨酸特异的磷酸化的增强,尚未见报道。因此,本实验对C_3H10 相似文献
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Wu Xiao-Han Fan Ming-Zhi Li Xue-Feng Piao Xuan-Chun Gao Ri Lian Mei-Lan 《Journal of Plant Growth Regulation》2021,40(4):1440-1449
Journal of Plant Growth Regulation - The adventitious root (AR) culture of Panax ginseng C.A. Meyer is an alternative route for mass production of ginsenosides. During the AR culture of P. ginseng,... 相似文献
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Joel Farkas Daehwan Chung Minseok Cha Jennifer Copeland Philip Grayeski Janet Westpheling 《Journal of industrial microbiology & biotechnology》2013,40(1):41-49
Methods for efficient growth and manipulation of relatively uncharacterized bacteria facilitate their study and are essential for genetic manipulation. We report new growth media and culture techniques for Caldicellulosiruptor bescii, the most thermophilic cellulolytic bacterium known. A low osmolarity defined growth medium (LOD) was developed that avoids problems associated with precipitates that form in previously reported media allowing the monitoring of culture density by optical density at 680 nm (OD680) and more efficient DNA transformation by electroporation. This is a defined minimal medium and does not support growth when a carbon source is omitted, making it suitable for selection of nutritional markers as well as the study of biomass utilization by C. bescii. A low osmolarity complex growth medium (LOC) was developed that dramatically improves growth and culture viability during storage, making it a better medium for routine growth and passaging of C. bescii. Both media contain significantly lower solute concentration than previously published media, allowing for flexibility in developing more specialized media types while avoiding the issues of growth inhibition and cell lysis due to osmotic stress. Plating on LOD medium solidified by agar results in ~1,000-fold greater plating efficiency than previously reported and allows the isolation of discrete colonies. These new media represent a significant advance for both genetic manipulation and the study of biomass utilization in C. bescii, and may be applied broadly across the Caldicellulosiruptor genus. 相似文献
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Huai Chen Qiuan Zhu Changhui Peng Ning Wu Yanfen Wang Xiuqing Fang Yongheng Gao Dan Zhu Gang Yang Jianqing Tian Xiaoming Kang Shilong Piao Hua Ouyang Wenhua Xiang Zhibin Luo Hong Jiang Xingzhang Song Yao Zhang Guirui Yu Xinquan Zhao Peng Gong Tandong Yao Jianghua Wu 《Global Change Biology》2013,19(10):2940-2955
With a pace of about twice the observed rate of global warming, the temperature on the Qinghai‐Tibetan Plateau (Earth's ‘third pole’) has increased by 0.2 °C per decade over the past 50 years, which results in significant permafrost thawing and glacier retreat. Our review suggested that warming enhanced net primary production and soil respiration, decreased methane (CH4) emissions from wetlands and increased CH4 consumption of meadows, but might increase CH4 emissions from lakes. Warming‐induced permafrost thawing and glaciers melting would also result in substantial emission of old carbon dioxide (CO2) and CH4. Nitrous oxide (N2O) emission was not stimulated by warming itself, but might be slightly enhanced by wetting. However, there are many uncertainties in such biogeochemical cycles under climate change. Human activities (e.g. grazing, land cover changes) further modified the biogeochemical cycles and amplified such uncertainties on the plateau. If the projected warming and wetting continues, the future biogeochemical cycles will be more complicated. So facing research in this field is an ongoing challenge of integrating field observations with process‐based ecosystem models to predict the impacts of future climate change and human activities at various temporal and spatial scales. To reduce the uncertainties and to improve the precision of the predictions of the impacts of climate change and human activities on biogeochemical cycles, efforts should focus on conducting more field observation studies, integrating data within improved models, and developing new knowledge about coupling among carbon, nitrogen, and phosphorus biogeochemical cycles as well as about the role of microbes in these cycles. 相似文献
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Despite efforts to elucidate its pathophysiology, ischemia–reperfusion injury lacks an effective preventative intervention. Because transient receptor potential cation channel subfamily M member 4 (TRPM4) is functionally expressed by many cell types in the cardiovascular system and is involved in the pathogenesis of various cardiovascular diseases, we decided to assess its suitability as a target of therapy. Thus, the aim of this study was to examine the possible cardioprotective effect of 9-phenanthrol, a specific inhibitor of TRPM4. Isolated Langendorff-perfused rat hearts were pretreated with Krebs–Henseleit (K–H) solution (control), 9-phenanthrol, or 5-hydroxydecanoate (5-HD, a blocker of the ATP-sensitive potassium channel) and then subjected to global ischemia followed by reperfusion with the K–H solution. To evaluate the extent of heart damage, lactate dehydrogenase (LDH) activity in the effluent solution was measured, and the size of infarcted area of the heart was measured by 2,3,5-triphenyltetrazolium chloride staining. In controls, cardiac contractility decreased, and LDH activity and the infarcted area size increased. In contrast, in hearts pretreated with 9-phenanthrol, contractile function recovered dramatically, and the infarcted area size significantly decreased. The cardioprotective effects of 9-phenanthrol was not completely blocked by 5-HD. These findings show that 9-phenanthrol exerts a cardioprotective effect against ischemia in the isolated rat heart and suggest that its mechanism of action is largely independent of ATP-sensitive potassium channels. 相似文献