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101.
Three species of the genus Trichodina are reported from the gills of marine fishes in south-eastern Tasmania, Australia. Two of these species are new: T. australis n. sp. from five atherinid fish species, Atherinosoma microstoma, Leptatherina presbyteroides, Kestratherina brevirostris, K. esox and K. hepsetoides; and T. nesogobii n. sp. from Nesogobius sp. 1. One previously reported species, T. jadranica Raabe, 1958, was also found on Nesogobius sp. 1. 相似文献
102.
Lanyue Zhang Zhiwen Yang Dingkang Chen Zebin Huang Yongliang Li Xinzi Lan Ping Su Wanyi Pan Wei Zhou Xi Zheng Zhiyun Du 《化学与生物多样性》2017,14(11)
Chemical compositions, antioxidative, antimicrobial, anti‐inflammatory, and cytotoxic activities of essential oils extracted from four common Curcuma species (Curcuma longa, Curcuma phaeocaulis, Curcuma wenyujin, and Curcuma kwangsiensis) rhizomes in P. R. China are comparatively studied. In total, 47, 49, 35, and 30 compounds are identified in C. longa, C. phaeocaulis, C. wenyujin, and C. kwangsiensis essential oils by GC/MS, and their richest compounds are ar‐turmerone (21.67%), elemenone (19.41%), curdione (40.23%) and (36.47%), respectively. Moreover, C. kwangsiensis essential oils display the strongest DPPH (2,2‐diphenyl‐1‐picrylhydrazyl) radical‐scavenging activity (IC50, 3.47 μg/ml), much higher than ascorbic acid (6.50 μg/ml). C. phaeocaulis oils show the best antibacterial activities against Escherichia coli (MIC, 235.54 μg/ml), Pseudomonas aeruginosa (391.31 μg/ml) and Staphylococcus aureus (378.36 μg/ml), while C. wenyujin and C. kwangsiensis oils show optimum activities against Candida albicans (208.61 μg/ml) and Saccharomyces cerevisiae (193.27 μg/ml), respectively. C. phaeocaulis (IC50, 4.63 μg/ml) and C. longa essential oils (73.05 μg/ml) have the best cytotoxicity against LNCaP and HepG2, respectively. C. kwangsiensis oils also exhibit the strongest anti‐inflammatory activities by remarkably down‐regulating expression of COX‐2 and TNF‐α. Therefore, due to their different chemical compositions and bioactivities, traditional Chinese Curcuma herbs should be differentially served as natural additives for food, pharmaceutical, and cosmetic. 相似文献
103.
104.
沈阳市东部土地利用格局变化 总被引:23,自引:6,他引:23
以沈阳市东部1976~1989年的历史航空像片为基础,以地理信息系统(GIS)技 术为手段,分析土地利用的空间格局及其变化.结果表明,针叶林、水田平均嵌块体大小增 加,旱地、落叶林、灌丛平均嵌块体大小减少;分数维值略有增加.预示嵌块体形状逐步复 杂化;多样性指数、均匀性指数增加.优势度和蔓延度指数由原来的1.6327和89.2022分 别减少到1.3226和88.2744,说明景观嵌块体的空间分布趋于均匀,嵌块体的聚集分布状 况将随时间的推移逐步分散化.此外.本文对沈阳东部土地利用格局变化的原因进行了剖 析. 相似文献
105.
Jian Yang Robert A. Spicer Teresa E. V. Spicer Nan Crystal Arens Frédéric M. B. Jacques Tao Su Elizabeth M. Kennedy Alexei B. Herman David C. Steart Gaurav Srivastava Rakesh C. Mehrotra Paul J. Valdes Naresh C. Mehrotra Zhe‐Kun Zhou Jiang‐Shan Lai 《Global Ecology and Biogeography》2015,24(10):1113-1125
106.
107.
从芝麻香型白酒高温大曲中分离到一株革兰氏阴性高温细菌Zm91,并对其进行形态学、生理生化代谢特征以及细胞代谢酶活性和药物敏感性分析,结合16S rRNA基因序列分析结果,Zm91鉴定为水生施莱格尔氏菌(Schlegelella aquatica).该菌株是首次从我国芝麻香型白酒高温大曲中分离得到的施莱格尔氏菌,其G+C mol%含量为67.5%,具有碱性磷酸盐酶、酯酶(C4)、脂酯酶(C8)、白氨酸芳胺酶、颉氨酸芳胺酶、胰凝乳蛋白酶、萘酚-AS-BI-磷酸水解酶及α葡萄糖苷酶活性,对青霉素、氨苄西林、链霉素、利福平敏感. 相似文献
108.
The present paper reports case study results of the risk assessment of transgenic Bt cotton on a non-target pest, cotton aphid, Aphis gossypii. Several types of techniques, i.e., electrical penetration graph (EPG), light and electron microscopy, bioassays and chemical analysis, were applied to investigate physical and chemical leaf factors of 2 transgenic Bt cotton lines (GK12 and GK19) and their pa-rental non-Bt cotton line (Simian3) associated with searching and feeding behaviors of cotton aphids on leaves or leaf extracts of cotton plants. EPG results showed that there were some differences among behaviors of cotton aphids on 2 Bt cotton and 1 non-Bt cotton lines. Cotton aphids performed similarly to leaf surface extracts from 3 cotton lines; and leaf surface chemicals, mainly volatiles and waxes, were almost identical in the components and concentrations among the cotton lines. However, three cotton lines were quite different from each other in the densities of certain kinds of covering trichomes. Therefore, the relationships between the physical characteristics and the searching behaviors of cotton aphids on the three cotton lines were constructed as the regression equations. Glandular trichomes and covering trichomes with 5 branches influenced the cotton aphids' searching behaviors effectively; and other trichomes with other branches affected aphids in varying ways. These results demonstrated that leaf surface physical factors of transgenic Bt cotton lines different from their parental non-Bt line could affect the penetration behaviors of non-target cotton aphids. Cotton aphids penetrate and feed more easily on two Bt cotton lines than on the non-Bt cotton line. 相似文献
109.
在基因治疗中, 实现目的基因的调控表达是非常重要的。然而, 传统基因载体的无调控地持续或不适当的表达会影响治疗效果, 甚至可能带来致命的副作用。在本研究中, 我们构建了一种带有DsRed红色荧光蛋白报告基因并可经RU486诱导的真核表达载体, 并在体外评估了其调控表达作用。利用分子生物学技术, 将DsRed基因和启动子, 以及RU486系统构建成单一的质粒载体PDC-RURED, 为减少RU486调控元件和基因表达元件之间的相互干扰, 在两者之间加入1.6 kb的绝缘子。经PCR检测和限制性酶切分析及序列测定均证实了载体的正确性。在转染HEK293细胞后, 运用荧光显微镜和流式细胞技术证实了该载体的调控能力。没有RU486时, 几乎没有红色荧光蛋白的表达, 而加入诱导剂RU486后, 最高可以实现红色荧光蛋白的40余倍的表达。实验结果表明构建的可经RU486诱导的新型真核表达载体可以实现对目的基因的表达时间和表达水平的调控, 为进一步的基因调控研究和和基因治疗提供了良好的工具。 相似文献
110.
The distribution of glucose and hexokinase activity was determined in the epithelial tissue of delayed bipedicled skin flaps in guinea pigs. The periods of "delay" were 1, 3, 7, 14, or 21 days. The flap survival was maximal (100% of the flap) when the flap elevation was performed either 7 or 14 days following the "delay" procedure. When the flap elevation was performed 1, 3, or 21 days following the "delay" procedure, the result was partial necrosis. A differential distribution of epithelial glucose was found within the bipedicled flaps. The lowest glucose level (30% of normal) was at a distance of 2 to 3.5 cm from the end of the caudal pedicle during the first day after the "delay" procedure. This decreased glucose content recovered toward normal levels during the later part of the "delay" period. The bipedicled flaps exhibited increased hexokinase activity during the 3-week period of the "delay," and the responses of hexokinase activity and tissue glucose levels to the "delay" procedure were reciprocal in the caudal half of the flaps. 相似文献