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71.
Chang H Zhang M Ji W Chen J Zhang Y Liu B Lu J Zhang J Xu P Xu T 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(12):4455-4460
Reversibly switchable fluorescent proteins (RSFPs) have attracted widespread interest for emerging techniques including repeated tracking of protein behavior and superresolution microscopy. Among the limited number of RSFPs available, only Dronpa is widely employed for most cell biology applications due to its monomeric and other favorable photochemical properties. Here we developed a series of monomeric green RSFPs with beneficial optical characteristics such as high photon output per switch, high photostability, a broad range of switching rate, and pH-dependence, which make them potentially useful for various applications. One member of this series, mGeos-M, exhibits the highest photon budget and localization precision potential among all green RSFPs. We propose mGeos-M as a candidate to replace Dronpa for applications such as dynamic tracking, dual-color superresolution imaging, and optical lock-in detection. 相似文献
72.
Wang L Jiang Y 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(11):E673-E677
Point-light biological motions, conveying various different attributes of biological entities, have particular spatiotemporal properties that enable them to be processed with remarkable efficiency in the human visual system. Here we demonstrate that such signals automatically lengthen their perceived temporal duration independent of global configuration and without observers' subjective awareness of their biological nature. By using a duration discrimination paradigm, we showed that an upright biological motion sequence was perceived significantly longer than an inverted but otherwise identical sequence of the same duration. Furthermore, this temporal dilation effect could be extended to spatially scrambled biological motion signals, whose global configurations were completely disrupted, regardless of whether observers were aware of the nature of the stimuli. However, such an effect completely disappeared when critical biological characteristics were removed. Taken together, our findings suggest a special mechanism of time perception tuned to life motion signals and shed new light on the temporal encoding of biological motion. 相似文献
73.
目的:探讨应用电化学测菌法检测变形链球菌的可行性。方法:利用本课题组前期建立的电化学测菌法检测变形链球菌,记录检测参数,并将电化学测菌法的检测结果与细菌培养结果进行比较。结果:①微流芯片样本通道内层流形成时间为(3.17±0.16)min,从进样到获得稳定电阻抗数据的时间为(10.20±0.16)min。②当变形链球菌浓度为104~109cells/mL时,细菌浓度C的对数与系统阻抗值Z呈良好的线性关系(R2=0.98)。③与细菌培养的检测结果相比,电化学测菌法获得的细菌数多,差异有统计学意义(P<0.05)。④变形链球菌浓度为105cells/mL时,电化学测菌法检测值与细菌培养法检测值之间的线性函数关系式为:y=0.94x+0.32E4(R2=0.95),两种方法的检测值高度正相关(P=0.001<0.01)。结论:电化学测菌法能为变形链球菌的快速检测提供新的思路。 相似文献
74.
目的:通过体外浸泡实验观察口腔铸造用银铟合金与浓台氏液发生腐蚀反应后表面形貌及粗糙度的变化,考察不同腐蚀反应时间浓台氏液对银铟合金的腐蚀情况。方法:制作口腔修复铸造用银铟合金测试件,对照组不与浓台氏液接触,实验组浸入浓台氏液发生腐蚀反应,反应时间分别为5sec、10sec、15sec、30sec、1min、5min、10min、30min,以扫描电子显微镜观察试件表面形貌,再以粗糙度仪检测试件表面粗糙度,应用SPSS16.0统计软件对各组合金样本粗糙度值做统计学检验。结果:扫描电子显微镜结果显示:浓台氏液对银铟合金的腐蚀是在整个金属表面上均匀进行的,且腐蚀产物有随腐蚀时间的增加而增加的趋势。试件表面粗糙度检测结果显示:各试验组表面粗糙度值与电镜观察到的材料表面腐蚀程度一致,随腐蚀时间的增加而有增加的趋势。统计结果显示:5sec、10sec组与对照组两两相比粗糙度差异有统计学意义(P<0.05),而10min组、15sec、30sec、1min组、5min、10min组、30min组两两相比粗糙度均无显著差异(P>0.05)。结论:浓台氏液与银铟合金的腐蚀反应特征为均匀腐蚀。腐蚀产物和表面粗糙度有随腐蚀时间的增加而增加的趋势。表面粗糙度与腐蚀时间不呈线性增长关系,具体表现为表面粗糙度10min到达较高水平,后在30min内随时间的增加,浓台氏液对银铟合金表面的腐蚀基本稳定。 相似文献
75.
目的:通过分析口腔专科夜间急诊病例的年龄、性别、就诊时间及病种,分析综合医院口腔科夜间急诊发病规律及特点.方法:收集我院2008.08-2011.07间,急诊病例1206例.按年龄分四个组,对各组就诊患者性别、就诊月份、病种进行统计,结果采用方差分析.结果:1、口腔专科夜间急诊病例的性别比例男∶女为1.32∶1;2、各年龄组就诊最高月份为7月,最低月份为2、3月;3、口腔专科夜间急诊就诊率高的病种分别为:颌面部外伤(38.64%),牙髓炎(13.76%),冠周炎(13.18%)和根尖周炎(8.96%).结论:针对综合医院口腔急诊患者的发病规律和特点,加强口腔急诊医疗救治的管理,提高口腔专科医师的临床急救技能,强化老年患者口腔疾病与全身健康关系的意识,熟悉和掌握临床急救知识,对提升口腔专科急诊医疗质量具有重要意义. 相似文献
76.
Cuimin Wang Xiaoju Hu Xiangmo Xie Pengfei Liu Juha Merilä Qiong Zhang Meng-Hua Li 《Conservation Genetics Resources》2013,5(4):915-924
We developed and characterized 113 polymorphic microsatellites in the Tibetan frog (Nanorana parkeri) using 454 GS-FLX next generation sequencing technology. These loci were tested in 46 individuals from two N. parkeri populations from the Tibetan plateau. The average number of alleles per locus was 8.09 (range = 2–20). The average observed heterozygosities (H O) per locus in the two populations were 0.58 (range = 0.04–1) and 0.29 (range = 0–0.87), respectively. These microsatellites will be useful for population and conservation genetics studies of N. parkeri and other closely related species. 相似文献
77.
Cordymin is a peptide purified from the medicinal mushroom Cordyceps sinensis. The present study investigated the effects of Cordymin in prevention of focal cerebral ischemic/reperfusion (IR) injury.
The right middle cerebral artery occlusion model was used in the study. The effects of Cordymin on mortality rate, neurobehavior,
grip strength, glutathione content, lipid Peroxidation, glutathione peroxidase activity, glutathione reductase activity, catalase
activity, Na+K+ATPase activity glutathione S transferase activity and on the regulation of C3 and C4 protein level, polymorphonuclear cells,
interleukin-1β and tumor necrosis factor-α in a rat model were studied respectively. Treatment (orally) of Cordymin significantly
boosted the defense mechanism against cerebral ischemia by increasing antioxidants activity related to lesion pathogenesis.
Restoration of the antioxidant homeostasis in the brain after reperfusion may have helped the brain recover from ischemic
injury. Moreover, Cordymin significantly inhibited infiltration of polymorphonuclear cells and IR-induced up-regulation of
the brain production of C3 protein level, interleukin-1β and tumor necrosis factor-α. Cordymin significantly improved the
outcome in rats after cerebral ischemia and reperfusion in terms of neurobehavioral function. Our findings suggest that cordymin
have a neuroprotective effect in the ischemic brain, which is due to the inhibition of inflammation and increase of antioxidants
activity related to lesion pathogenesis. Cordymin can be used as potential preventive agent against cerebral ischemia-reperfusion
injury. 相似文献
78.
79.
There have been considerable advances in the understanding of species concepts in the genus Colletotrichum. This has lead to the need to carry out fresh surveys of Colletotrichum species associated with important hosts. Colletotrichum species are associated with Citrus plants as saprobes, important pre-harvest and post-harvest pathogens, as well as endophytes. In this study, a total of 312 Colletotrichum strains were isolated from leaves, shoots and fruits of cultivated Citrus and Fortunella species with or without disease symptoms across the main citrus production areas in China. The morphology of all strains were studied and multilocus (ACT, TUB2, CAL, GAPDH, GS, ITS) phylogeny established. Strains were from four important species complexes of Colletotrichum, namely C. gloeosporioides species complex, C. boninense species complex, C. acutatum species complex and a final group including C. truncatum, which was rare on Citrus species. The species belonging to the C. gloeosporioides species complex comprised C. gloeosporioides and C. fructicola, the C. boninense complex comprised C. karstii and a new species C. citricola and the C. acutatum complex included a new species, C. citri. The ability of strains to cause anthracnose on citrus fruits was tested by inoculation and strains of Colletotrichum gloeosporioides, C. fructicola and C. truncatum were pathogenic. 相似文献
80.
Anthracnose disease of Proteaceae has in the past chiefly been attributed to infections by C. acutatum, C. boninense and C. gloeosporioides. In the present study, a multi-locus phylogenetic analysis (ACT, CAL, CHS-1, GAPDH, GS, ITS, TUB2) revealed that strains of the C. gloeosporioides complex associated with Proteaceae belong to at least six species. These include C. alienum, C. aotearoa, C. kahawae (subsp. ciggaro), C. siamense, and two new taxa, C. proteae and C. grevilleae. The most economically important pathogen of Proteaceae seems to be C. alienum, and not C. gloeosporioides as previously reported. All taxa associated with Proteaceae are morphologically described on different media in culture, except strains of C. siamense, which proved to be sterile. Furthermore, C. populi is synonymised with C. aenigma. 相似文献