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281.
We have isolated the cDNA and genomic sequences encoding the major isozyme of manganese peroxidase, MnP3, from the white rot basidiomycetePleurotus ostreatus strain IS1. The genemnp3 is interrupted by 10 introns and encodes a mature protein of 357 amino acid residues with a 26-amino-acid signal peptide. The amino acid residues known to be involved in peroxidase function and those that form the Mn-binding site in thePanerochaete chrysosporium MnP isozyme are conserved in MnP3. Comparison of the deduced primary structure of MnP3 with those of other peroxidases from various white rot fungi suggested that MnPs fromP. ostreatus andTrametes versicolor belong to a subgroup that is more similar to the lignin peroxidases than MnPs fromP. chrysosporium orCeriporiopsis subvermispora.  相似文献   
282.
Aluminum ammonium sulfate was used as a new catalyst for glyoxal to minimize the decrease of physical properties of durable press cotton fabrics, and the optimum treatment conditions such as the concentration of glyoxal, molar ratio of catalyst to glyoxal, curing temperature and time were investigated. The retention of tensile strength and the whiteness of fabrics treated with glyoxal/aluminum ammonium sulfate was increased as much as to the degree of that obtained with glyoxal/aluminum sulfate while wrinkle recovery angles were as good as those of the latter. Some additives such as DEG, polyurethane and softener were used to improve the physical properties. When DEG or polyurethane was added to the glyoxal padding solution, wrinkle recovery angle (WRA) significantly increased while tensile strength and whiteness were not influenced. DEG added to the glyoxal padding solution increased the durability of DP finish. The softener added to the glyoxal padding solution increased the WRA of treated fabrics while it decreased the tensile strength slightly. The whiteness of fabrics treated with glyoxal alone increased while the WRA decreased slightly.  相似文献   
283.
The substance secreted by mussels, also known as nature’s glue, is a type of liquid protein that hardens rapidly into a solid water-resistant adhesive material. While in seawater or saline conditions, mussels can adhere to all types of surfaces, sustaining its bonds via mussel adhesive proteins (MAPs), a group of proteins containing 3,4-dihydroxyphenylalanine (DOPA) and catecholic amino acid. Several aspects of this adhesion process have inspired the development of various types of synthetic materials for biomedical applications. Further, there is an urgent need to utilize biologically inspired strategies to develop new biocompatible materials for medical applications. Consequently, many researchers have recently reported bio-inspired techniques and materials that show results similar to or better than those shown by MAPs for a range of medical applications. However, the susceptibility to oxidation of 3,4-dihydroxyphenylalanine poses major challenges with regard to the practical translation of mussel adhesion. In this review, various strategies are discussed to provide an option for DOPA/metal ion chelation and to compensate for the limitations imposed by facile 3,4-dihydroxyphenylalanine autoxidation. We discuss the anti-proliferative, anti-inflammatory, anti-microbial activity, and adhesive behaviors of mussel bio-products and mussel-inspired materials (MIMs) that make them attractive for synthetic adaptation. The development of biologically inspired adhesive interfaces, bioactive mussel products, MIMs, and arising areas of research leading to biomedical applications are considered in this review.  相似文献   
284.
285.
u| li]? Genotypic variation in wood total and partial shrinkage, basic density and growth traits was estimated in 51÷2 year old Acacia auriculiformis trees in a clonal test. li]? In the tangential, radial and longitudinal directions, the mean values were 2.64%, 1.64% and 0.77% for partial shrinkage, and 5.92%, 3.23%, and 0.96% for total shrinkage, respectively. Total and partial transverse shrinkage were significantly greater in sapwood than in heartwood. li]? Clonal repeatability (H C 2 ) estimates for partial shrinkage were lower than those for total shrinkage, and heartwood shrinkages had lower H C 2 than those for sapwood. Estimates of H C 2 were from 0.32 to 0.38 for total transverse shrinkage, comparable to H C 2 for both total and partial volumetric shrinkages (0.40 and 0.32, respectively). However, H C 2 for longitudinal shrinkages, total and partial coefficients of anisotropy were only from 0.09 to 0.18. li]? The genotypic coefficients of variation of all shrinkage traits varied from 5.45% to 8.02%. Total shrinkage was strongly positively correlated with partial shrinkage in each dimension. Genotypic correlations were not significant between shrinkage and growth traits or density. Strong and significant correlations between transverse shrinkage in heartwood and sapwood (0.87) indicated that juvenile shrinkage is a good genetic indicator of this trait in older trees. Utilisation du retrait du bois dans l’amélioration de l’Acacia auriculiformis A. Cunn. ex Benth à croissance rapide au Vietnam.  相似文献   
286.
The azuki bean in Korea consists of seven domestic varieties which have been developed and registered for the public during last 25 years. Here, we present a simple but reliable method to screen and identify Korean azuki bean varieties. A method based on simple sequence repeat (SSR) markers is widely used for prominent gene identification and variety discrimination. In molecular biology, real-time polymerase chain reaction (PCR) is a laboratory technique based on the polymerase chain reaction that is used to amplify and simultaneously quantify a targeted DNA molecule. It enables easy detection of a specific sequence in a DNA sample without performing electrophoresis and further processes. For separation of seven Korean azuki bean varieties, 110 unique azuki bean SSR markers from an (AG)n-enriched library were selected, synthesized and used for polymerase chain reaction (PCR). Data were taken through acrylamide gel electrophoresis and automated multi-capillary electrophoresis system for selection of specific markers and then changed into proper formats for data mining analysis. Ten primer pairs that showed high polymorphism were chosen for the indepth study. These ten primers were re-amplified with real-time PCR and checked the cycle threshold (Ct) and temperature (Tm) for comparison of amplification sequence in seven varieties. Consequently, a total of 20 alleles and 6 SSR primers were detected from the standard PCR amplification. Within these 6 primers, 7 alleles of 3 SSR primers were isolated for variety identification. From real-time PCR results, 3 SSR primers were selected as efficient markers for discrimination of seven Korean azuki bean varieties. The approach described here could be applied in monitoring our varieties and can be adapted in the azuki bean breeding program.  相似文献   
287.
Journal of Soils and Sediments - Mine and smelter soil contaminations with Pb, Cu, Cd, and Zn have become serious problems in China, because of anthropogenic activities. Little is known about the...  相似文献   
288.
采用了650nm红色发光二极管(LED)的矩阵(6×8)作为激发光源,构建了一种基于MINI-PAM荧光仪的调制脉冲式在线检测叶绿素荧光系统。利用该系统分别对番茄苗期、花期、果期活体叶片的荧光强度与激发光源(LED)光强关系进行试验研究。通过对可编程电源来调节LED光强(在0~1 700μmol/m2.s之间),以50mA为步进值依次增加,并利用Excel软件对测得的荧光值F进行分析。结果显示:电流值在3 700mA以下,每一时期植株叶片的荧光强度与恒流源输出电流强度具有显著的线性关系,决定系数R2>0.97。以此研究为基础,建立了荧光强度与激发光强度的关系模型,模型可靠性高,能够比较真切地反映出荧光强度与激发光强之间的关系。  相似文献   
289.
To study C chemistry and nutrient dynamics in decomposing residues and P dynamics at the residue-soil interface, young pea (Pea-Y) and mature pea (Pea-M) residues were incubated in a sandy soil with low P availability. The study was conducted in microcosms in which the residues were separated from the soil by a nylon mesh. Controls consisted of microcosms without residues. Residues and the soil in the immediate vicinity of the nylon mesh were sampled after 5, 15, 28, 42 and 61 days. Residue chemistry was studied by 13C nuclear magnetic resonance (NMR) spectroscopy and determination of C, N and P concentrations. Compared to Pea-M, Pea-Y was characterised by higher N and P concentrations, higher percentage of proteins, esters, fatty acids and sugars, and was more easily decomposable in the first 15 days. Pea-M residues had a greater percentage of cellulose and other polysaccharides than Pea-Y and showed a more gradual loss in dry weight. Differences in C chemistry and N and P concentration between the residues decreased with time. The decomposition of Pea-Y and Pea-M residues resulted in an increase in microbial P in the residue-soil interface compared to the control, but available P was increased only in the vicinity of Pea-Y residues.  相似文献   
290.
Anthocyanin is a natural plant pigment and potent antioxidant. This study was designed to investigate the effects of anthocyanin extracted from black soybeans on a rat model of benign prostatic hyperplasia (BPH), a disease associated with the geriatric population. Thirty male rats were divided into five experimental groups: a control group, a BPH-induced group, and three BPH-induced groups that received oral doses of anthocyanin (40, 80, and 160 mg/kg). Prostate hyperplasia was induced by the administration of testosterone propionate for 4 weeks. Following BPH induction, the anthocyanin-treated groups received the compound for 4 weeks. After anthocyanin treatment, the prostates from the rats in all groups were removed, weighed, and subjected to histological examination. Apoptosis in the prostates was measured by the TUNEL assay. The mean prostate weight for the control animals was 674.17 ± 28.24 mg, whereas the BPH-induced rats had a mean prostate weight of 1098.33 ± 131.31 mg. The mean prostate weights for the rats receiving 40, 80, and 160 mg/kg anthocyanin were 323.00 ± 22.41, 324.00 ± 26.80, and 617.50 ± 31.08 mg, respectively. The average prostate weight in the BPH-induced group was significantly higher than in the control group (p < 0.05), whereas the prostate weights in the anthocyanin-administered groups were significantly lower than in the BPH-induced group (p < 0.05). Injected testosterone led to prostatic hyperplasia as observed histologically, but anthocyanin administration helped to prevent this change. Apoptotic body counts were significantly higher in groups receiving anthocyanin than in the BPH-induced group (p < 0.05). These results suggest that anthocyanin may be effective in decreasing the volume and suppressing the proliferation of the prostate. Further studies are needed to better understand the mechanisms and actions of anthocyanin, and these studies may lead to the clinical application of anthocyanin in treating BPH.  相似文献   
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