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Distributions of rupture sites of fission yeast cells ruptured by glass beads have been related to a new morphometric analysis. As shown previously (Johnson et al.,Cell Biophysics, 1995), ruptures were not randomly distributed nor was their distribution dictated by geometry, rather, ruptures at the extensile end were related to cell length just as the rate of extension is related to cell length. The extension patterns of early log, mid-log, late log, and stationary phase cells from suspension cultures were found to approximate the linear growth patterns of Kubitschek and Clay (1986). The median length of cells was found to decline through the log phase in an unbalanced manner.  相似文献   
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Summary For the secretion of human lipocortin-1 (LC-1) in yeast, a expression and secretion vector was constructed by using the promoter and signal sequence of glucoamylase gene (STA1) of Saccharomyces diastaticus. After the cDNA of human LC-1 was ligated with the secretion vector, the resulting hybrid plasmid was transformed into S. diastaticus. When the recombinant S. diastaticus was cultivated in YPD medium, LC-1 was expressed and secreted into the extracellular medium, yielding LC-1 protein at a concentration of 2.5 g/mL.  相似文献   
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Mixed-phase plants of Griffithsia japonica Okamura spontaneously occurred in a laboratory culture. Four female plants produced tetrasporangia and spermatangia in addition to their normal female reproductive structures (bisexual/mixed-phase plants), and four male plants produced tetrasporangia as well as spermatangia (male/mixed-phase plants). To determine the nuclear ploidy level of these mixed-phase plants, relative nuclear sizes of male, female, tetrasporangial, and mixed-phase plants were measured using a microscopic image analysis system. Haploid gametophytes could be distinguished from diploid tetrasporophytes by relative nuclear sizes, with the later having nuclei twice the size of the former. Relative nuclear sizes of the mixed-phase plants were similar to those of the haploid plants. Thus, the mixed-phase plants were determined to be haploid. Haploid mixed-phase plants of G. japonica have a potential to produce male, female and tetrasporangial reproductive structures. Sex determination models are discussed to explain "haploid" mixed-phase phenomena in red algae .  相似文献   
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During the first four days after unilateral nephrectomy the free tyrosine content in plasma, liver and hypertrophic kidney was decreased by more than 50% as compared with the values observed in intact rat. After sham operation, the content of tyrosine was decreased to the same extent. The activity of tyrosine aminotransferase in liver was doubled two days after sham operation: no such increase was observed after unilateral nephrectomy. At the same time a decline of the enzyme activity in kidney was demonstrated after both types of surgery. Hydrocortisone in a single i.p. dose stimulated enzyme activity in the liver of intact rats three-fold, and more than four-fold after nephrectomy and sham operation. In kidney of intact rat, as a result of hydrocortisone treatment, the enzyme activity was doubled; it was, however, insensitive to this treatment after unilateral nephrectomy, and increased only by 20% after sham operation. It is suggested that the changes in tyrosine content and tyrosine aminotransferase activity observed after unilateral nephrectomy were not due to stress alone, but underwent regulation aimed at assuring a sufficient level of this amino acid for metabolism.  相似文献   
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Gonggeom‐ji pond is the first protected paddy field wetland area, designated by the Ministry of Environment of Korea in 2011, because of its high biodiversity and historic value. It contains reservoirs, paddy fields, and a forest site that provides diverse niches for insects. Quantitative methods were used in this study to estimate the insect diversity of this region. A transect of 50 m was designated in each site (reservoirs, paddy fields, and a forest site). Data were collected using sweeping and pitfall traps along each transect in May, August, and November 2017, representative of the seasons—spring, summer, and autumn, respectively. As a result, a total of 1079 individual insects representing 170 species from 60 families within nine orders were collected. Diversity, richness, and evenness indices were the highest in the forest site in May (4.77, 8.6, and 0.91, respectively). The dominance index was the highest in the forest site in November (0.64). Similarity index was the highest in the reservoir in May and August (0.519). These results would help compare different sites and their vegetation to assess relationships between insects and habitats.  相似文献   
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Probiotics and Antimicrobial Proteins - Pseudomonas aeruginosa is a potential source of food contamination that leads to food spoilage and infections as a result of the generation of biofilm and...  相似文献   
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