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121.
Various conditions for obtaining hybrids of the auxotrophic mutants SH1509 and SH1512 of Saccharomyces cerevisiae by electrofusion were investigated. An AC field of 400 Vp/cm and a DC field of 2 square pulses (7 kV/cm; 60/βsec each) at an interval of 0.5 sec were effective. Treatment with 0.2 (SH1509) or l.0 mg/ml (SH1512) Zymolyase for 1 or 1.5 hr was essential. As to the molarity of the osmotic stabilizer (sorbitol), the hybrid yield peaked at 0.6 m. The presence of CaCl2 (up to 0.4 mm) or 0.1 mm CaCl2 with 0.1 mm MgCl2 enhanced the yield. The temperature of the spheroplast suspension during pulsations also affected the yield, the most suitable temperature being 28°C.  相似文献   
122.
Pyrethrin II, cinerin II, allethrin II, pyrethrin II isomer, and allethrin II isomer were prepared by esterification of rethrolons with (+)-trans-pyrethric acid and (+)-trans-methyl-2,2-dimethyl-3-(2′-carboxy-l′-propenyl) cyclopropanecarboxylate and their relative toxicities to pyrethrin I, cinerin I and allethrin I against houseflies were measured by counting “mortality” and “knock-down percent”  相似文献   
123.
Ester Formation by Alcohol Acetyltransferase from Brewers’ Yeast   总被引:2,自引:0,他引:2  
Alcohol acetyltransferase responsible for the formation of acetate esters during beer fermentation was found to be localized at the cell membrane of brewers’ yeast. This cell membrane-bound enzyme was purified 120-fold by solubilization with Triton X-100, gel filtration on a Sepharose 6B column and chromatography on a DEAE-Sephadex A-50 column. The enzyme was most active at 30°C at pH 7 ? 8. It was least active against C3 alcohol among C1 ? C6 alcohols, and slightly more active against straight-chain alcohols than against branched-chain alcohols with the same carbon number. The enzyme was strongly inhibited by unsaturated fatty acids, heavy metal ions and sulfhydryl reagents.  相似文献   
124.
In connection with disclosure of a new class of insecticides, the modified phenylacetates, six new optically active α-isopropy-4-substituted phenylacetic acids whose substituents are respectively 4-methyl,4-methoxy, 4-fluoro, 4-chloro, 4-bromo and 3,4-methylenedioxy group were prepared by optical resolution and their absolute configurations were determined by comparative ORD with α-isopropylphenylacetic acid derivatives whose absolute configuration is known as (S)-(²). Esters of the (S)-(²)-acids with 5-benzyl-3-furylmethanol were nearly twice toxic to Musca domestica than those of the racemic esters. Optical purities of the resolved acids were determined by GLC and NMR (with Eu-FOD) as (?)-methyl esters.  相似文献   
125.
Among photomixotrophic green calluses tested (N. rustica. N. tobacum L. cv. BY-4 and Samsun), the callus of Samsun had the highest contents of chlorophyll and chloroplast lipids, such as monogalactosyldiglyceride (MGDG), digalactosyldiglyceride (DGDG), sulfoquinovosyldigly-ceride (SQDG) and phosphatidylglycerol (PG). However, the chlorophyll and chloroplast lipids in the green callus of Samsun were still 1/6 and 1/3 of that in the parent leaves, respectively. The relative content of a-linolenate in MGDG, DGDG and SQDG of the green calluses were higher than that of the white calluses. The ratios of hexadecatrienoate in MGDG and hexadeceno-ate 3-trans) in PG in the green calluses were trace or less compared with that of the parent leaves. The crude lipids and total fatty acid contents of the chlorophyll deficient leaves (N. taba-cum L. cv. Consolation 402 and Dominant Aurea Su/su) were almost the same as those of the normal leaves (cv. BY-4 and Samsun), although the chlorophyll contents of the chlorophyll deficient leaves were 1/3 ~ 1/4 of that of the normal leaves. The ratios of chloroplast lipids in the total polar lipids in the chlorophyll deficient leaves were a little lower than that in the normal green leaves, but the former had a slightly higher ratio of phospholipids such as phosphatidylcholine and phosphatidylethanolamine than the latter. There were few differences in the fatty acid compositions of each individual lipid betweeen both types of leaves.  相似文献   
126.
Streptomyces sp. No. B-1625, which was identified as a strain of Streptomyces antibioticus, is a typical producer of actinomycin, but also produces minor acidic antibiotic components (FA), besides actinomycins X2, D and X. The FA-components, which were obtained with a high-producing mutant, 11M-21, showed antibacterial and antitumor activities, and also similar visible and UV absorption spectra to those characteristic of actinomycin. The FA-components were separated into five components, FA1 FA, FA, FA and FA, on TLC. Among them, one component, FA, isolated in a purified state as an orange powder, has a composition of C, 52.97: H, 6.34: N, 10.48%, and is active against B. subtilis at a MIC of 5mcg/ml. The FA component showed pKa′ of 5.4 and 12.0 and λmax at 443, 427 and 233 nm. From these properties, FA is considered to be an acidic actinomycin congener.  相似文献   
127.
128.

Background

Do brain training games work? The beneficial effects of brain training games are expected to transfer to other cognitive functions. Yet in all honesty, beneficial transfer effects of the commercial brain training games in young adults have little scientific basis. Here we investigated the impact of the brain training game (Brain Age) on a wide range of cognitive functions in young adults.

Methods

We conducted a double-blind (de facto masking) randomized controlled trial using a popular brain training game (Brain Age) and a popular puzzle game (Tetris). Thirty-two volunteers were recruited through an advertisement in the local newspaper and randomly assigned to either of two game groups (Brain Age, Tetris). Participants in both the Brain Age and the Tetris groups played their game for about 15 minutes per day, at least 5 days per week, for 4 weeks. Measures of the cognitive functions were conducted before and after training. Measures of the cognitive functions fell into eight categories (fluid intelligence, executive function, working memory, short-term memory, attention, processing speed, visual ability, and reading ability).

Results and Discussion

Our results showed that commercial brain training game improves executive functions, working memory, and processing speed in young adults. Moreover, the popular puzzle game can engender improvement attention and visuo-spatial ability compared to playing the brain training game. The present study showed the scientific evidence which the brain training game had the beneficial effects on cognitive functions (executive functions, working memory and processing speed) in the healthy young adults.

Conclusions

Our results do not indicate that everyone should play brain training games. However, the commercial brain training game might be a simple and convenient means to improve some cognitive functions. We believe that our findings are highly relevant to applications in educational and clinical fields.

Trial Registration

UMIN Clinical Trial Registry 000005618.  相似文献   
129.
Bruguiera hainesii (Rhizophoraceae) is one of the two Critically Endangered mangrove species listed in the IUCN Red List of Threatened Species. Although the species is vulnerable to extinction, its genetic diversity and the evolutionary relationships with other Bruguiera species are not well understood. Also, intermediate morphological characters imply that the species might be of hybrid origin. To clarify the genetic relationship between B. hainesii and other Bruguiera species, we conducted molecular analyses including all six Bruguiera species using DNA sequences of two nuclear genes (CesA and UNK) and three chloroplast regions (intergenic spacer regions of trnL-trnF, trnS-trnG and atpB-rbcL). For nuclear DNA markers, all nine B. hainesii samples from five populations were heterozygous at both loci, with one allele was shared with B. cylindrica, and the other with B. gymnorhiza. For chloroplast DNA markers, the two haplotypes found in B. hainesii were shared only by B. cylindrica. These results suggested that B. hainesii is a hybrid between B. cylindrica as the maternal parent and B. gymnorhiza as the paternal one. Furthermore, chloroplast DNA haplotypes found in B. hainesii suggest that hybridization has occurred independently in regions where the distribution ranges of the parental species meet. As the IUCN Red List of Threatened Species currently excludes hybrids (except for apomictic plant hybrids), the conservation status of B. hainesii should be reconsidered.  相似文献   
130.
Creation of new potent antifouling active compounds is important for the development of environmentally friendly antifouling agents. Fifteen isocyanide congeners derived from proteinogenic amino acids were synthesized, and the antifouling activity and toxicity of these compounds against cypris larvae of the barnacle Balanus amphitrite were investigated. All synthesized amino acid‐isocyanides exhibited potent anti‐barnacle activity with EC50 values of 0.07 – 10.34 μg/ml after 120 h exposure without significant toxicity. In addition, seven compounds showed more than 95% settlement inhibition of the cypris larvae at 10 μg/ml after 120 h exposure without any mortality observed. Considering their structure, these amino acid‐isocyanides would eventually be biodegraded to their original nontoxic amino acids. These should be useful for further research focused on the development of environmentally friendly antifoulants.  相似文献   
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