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Vitex rotundifolia L.f. is a woody perennial and has sexual and asexual modes of reproduction. Allozyme study was conducted on 550 plants in 13 Korean populations. The levels of genetic variability and divergence within and among populations, respectively, are considerably lower and higher than the mean values for woody plants with similar life history tralts. Mean percentage of polymorphic loci (P P), mean number of alleles per locus (A P), and mean genetic diversity (He P) within populations ofV. rotundifolia were: 16.7%, 1.21, and 0.047. On average, about 79% of the total variation inV. rotundifolia was common to all populations (meanG ST=0.208). In addition, significant differences in allele frequencies among populations were found in all polymorphic loci examined (P<0.001). On the other hand, levels of genotypic diversity within and among populations were moderate. About 44% (18/41) of multilocus genotypes were “local genotypes” (genotypes occurring in only one population), whereas only one “widespread genotype” (genotypes occurring in more than 75% of the populations) were detected. The mean number of multilocus genotypes per population (G) and mean genotypic diversity index (D G) were 8.4 and 0.74, respectively. Most common multilocus genotypes found in populations were homozygous for five polymorphic loci. The abundance of ramets of these genets is responsible for the low levels of expected heterozygosity within populations. The results indicate that clonal reproduction may act as an enhancer of genetic drift by reducing effective size of local populations ofV. rotundifolia.  相似文献   
2.
Undoubtedly, biotechnology has a tremendous impact on our daily lives. As a result of this and in parallel to the advancement of knowledge in this field of applied research, consumer awareness of the potential benefits and risks of this technology has steadily increased, leading to a thorough investigation of the public perception of biotechnology in the past years. Indeed, it has become clear that it is in the general interest of science and especially of applied research to inform the public of its advances. A promising next step is to strengthen biotechnology communication in scholastic institutions. In this paper, we investigate the perception of biotechnology in a specific target group, namely high-school students in the 16–20-year-old age range. We conducted a questionnaire-based survey on a total of 1410 students in six European countries to investigate students’ perception, concern, scientific knowledge, and awareness. Our data revealed some unexpected patterns of acceptance and concern about biotechnology. Knowledge analysis indicated that pupils lack specific knowledge about biotechnological applications and their interest in biotechnology appeared to be linked to knowledge. Analysis of specific questions about teaching practices at schools suggests that a better targeted choice in media as vehicles for information together with selected speakers could be instrumental in increasing students’ interest in science and more specifically in biotechnology.  相似文献   
3.
Antrodia camphorata (A. camphorata) is well known in Taiwan as a traditional Chinese medicine. The purpose of this study was to evaluate the ability of aqueous extract from A. camphorata mycelia to protect normal human erythrocytes against oxidative damage in vitro. Oxidative hemolysis and lipid/protein peroxidation of erythrocytes induced by the aqueous peroxyl radical [2,2'-Azobis(2-amidinopropane) dihydrochloride, AAPH] were suppressed by A. camphorata mycelia in a time-and concentration-dependent manner. A. camphorata mycelia also prevented the depletion of cytosolic antioxidant glutathione (GSH) and ATP in erythrocytes. Moreover, cultured human endothelial cell damage induced by AAPH was suppressed by A. camphorata mycelia. Interestingly, A. camphorata mycelia exhibited significant cytotoxicity against leukemia HL-60 cells but not against cultured human endothelial cells. These results imply that A. camphorata mycelia may have protective antioxidant and anticancer properties.  相似文献   
4.
Protoplast fusion between Lactobacillus casei and Lactobacillus acidophilus   总被引:3,自引:0,他引:3  
Summary From the fusion between Lactobacillus casei and Lactobacillus acidophilus, 8 fusants were selected: Four were able to ferment maltose, lactose, galactose and mannose, but two had greater abilities of acid production than parents. Increased values of up to 7.6–8 % in -galactosidase activity were obtained from two when compared to that of L. acidophilus, whereas another 2 had activities of 800 and 548 nmol/mg protein/min comparable to that of L casei giving a value of 400 nmol/mg protein/min in phospho--galactosidase activity.  相似文献   
5.
Summary Continuous cultivation of Rhodotorula sp. Y-38 was carried out on ethanol, acetic acid or acetaldehyde. At a feed concentration of 1.0 % (w/v) ethanol, the cell yield of 64 g/100 g ethanol and crude protein of 52 g/100 g biomass were obtained at D=0.5 h-1. The respective value of the content of amino acids and nucleic acids was 42.6 and 9.4 g/100 g biomass. At 2.0 % (w/v) acetic acid, cell yield was found to be 50 g/100 g acetic acid at D=0.4 h-1. The optimum dilution rate ranged between 0.3 and 0.4 h-1. At 0.05 % (w/v) acetaldehyde, the maximum cell yield was obtained at D=0.14 h-1.  相似文献   
6.
Four new maleimide derivatives, antrocinnamomins E–H ( 1 – 4 , resp.), together with (3S,4R)‐1‐hydroxy‐3‐(4‐hydroxyphenyl)‐4‐(2‐methylpropyl)pyrrolidine‐2,5‐dione ( 5 ) and ergosterol were isolated from the mycelia of Antrodia cinnamomea BCRC 36799. The structures were elucidated by 1D‐ and 2D‐NMR spectroscopy, and mass spectrometry. Compounds 1 – 5 were evaluated for their inhibitory effects on nitric oxide (NO) production by macrophages. Compounds 2 and 4 showed stronger inhibition of NO production than the positive control quercetin.  相似文献   
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