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1.
Honghong Yang Yuanyuan Zhang Zhihai Wang Shixun Zhong Guohua Hu Wenqi Zuo 《Bioelectromagnetics》2020,41(3):219-229
To investigate the possible mechanisms for biological effects of 1,800 MHz mobile radiofrequency radiation (RFR), the radiation-specific absorption rate was applied at 2 and 4 W/kg, and the exposure mode was 5 min on and 10 min off (conversation mode). Exposure time was 24 h short-term exposure. Following exposure, to detect cell DNA damage, cell apoptosis, and reactive oxygen species (ROS) generation, the Comet assay test, flow cytometry, DAPI (4′,6-diamidino-2-phenylindole dihydrochloride) staining, and a fluorescent probe were used, respectively. Our experiments revealed that mobile phone RFR did not cause DNA damage in marginal cells, and the rate of cell apoptosis did not increase (P > 0.05). However, the production of ROS in the 4 W/kg exposure group was greater than that in the control group (P < 0.05). In conclusion, these results suggest that mobile phone energy was insufficient to cause cell DNA damage and cell apoptosis following short-term exposure, but the cumulative effect of mobile phone radiation still requires further confirmation. Activation of the ROS system plays a significant role in the biological effects of RFR. Bioelectromagnetics. © 2020 The Authors. Bioelectromagnetics published by Wiley Periodicals, Inc. 相似文献
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Food Biophysics - Caffeic acid phenethyl ester (CAPE) has high cytotoxicity against various cancer cells but has low water solubility and poor bioavailability. The objective of this work was to... 相似文献
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S. Shi Y. Huang Y. Zhong Y. Du Q. Zhang H. Chang D. E. Boufford 《Plant Systematics and Evolution》2001,230(1-2):13-24
Phylogenetic relationships of the three genera of the family Altingiaceae, i.e., Altingia, Liquidambar and Semiliquidambar, based on matK sequences and the intergenic spacer between the psaA and ycf3 genes (PY-IGS) of cpDNA, and on the internal transcribed spacer (ITS) of nrDNA were studied. Phylogenetic trees based on
the three data sets (matK, PY-IGS and ITS) were generated using Hamamelis japonica and Mytilaria laosensis (Hamamelidaceae), Cercidiphyllum japonicum (Cercidiphyllaceae), and Daphniphyllum calycinum (Daphniphyllaceae) as outgroups. The partition-homogeneity tests indicated that the three data sets and the combined data
are homogeneous. A combined analysis also generated a strongly supported phylogeny. The phylogenetic trees show that the North
American and western Asian species, L. styraciflua and L. orientalis, respectively, form a monophyletic group which is sister to the clade including all Asian species in the family. The genus
Liquidambar is paraphyletic with Altingia and Semiliquidambar nested within. Phylogenetic analyses of the molecular data indicate that taxonomic reexamination of the generic delimitation
in the Altingiaceae is needed.
Received December 20, 2000 Accepted June 25, 2001 相似文献
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Sample preparation is key to the success of proteomics studies. In the present study, two sample preparation methods were tested for their suitability on the mature, recalcitrant leaves of six representative perennial plants (grape, plum, pear, peach, orange, and ramie). An improved sample preparation method was obtained: Tris and Triton X-100 were added together instead of CHAPS to the lysis buffer, and a 20% TCA-water solution and 100% precooled acetone were added after the protein extraction for the further purification of protein. This method effectively eliminates nonprotein impurities and obtains a clear two-dimensional gel electrophoresis array. The method facilitates the separation of high-molecular-weight proteins and increases the resolution of low-abundance proteins. This method provides a widely applicable and economically feasible technology for the proteomic study of the mature, recalcitrant leaves of perennial plants. 相似文献
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Food availability is important to the dynamics of animal social organizations or populations. However, the role of winter
food availability in animal population dynamics is still controversial. We carried out an experimental study to test Lack’s
hypothesis that reduced food in winter limits survival and spring numbers of breeding individuals of social groups, using
the Mongolian gerbil (Meriones unguiculatus) as model species. We established 24 gerbil social groups in 24, 10 × 10 m, pens in September 2008. We provided wheat seeds
as supplemental food in 12 enclosures from September 2008 to March 2009; the other 12 enclosures, not provided with supplemental
food, served as controls. We live-trapped gerbils at a 2-week interval from September to April. Supplemental food during winter
increased biweekly survival by 10% relative to that in control groups. Only four control social groups survived to the end
of our study whereas all 12 food-supplemented social groups survived through our study period. Supplemental food also increased
cumulative numbers of recruits and group sizes of gerbils. We conclude that winter food availability limits winter survival
and spring social groups or population sizes of Mongolian gerbils. 相似文献
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