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351.
Hsiang-Jung Tseng Shan-hui Hsu Mien-Win Wu Tien-Hsiang Hsueh Pei-Chi Tu 《Fibers and Polymers》2009,10(1):53-59
Chitosan is a natural non-toxic biopolymer and is widely used in various fields because of the antimicrobial activities. In
this study, the properties of nylon textiles grafted with chitosan oligomer or chitosan polymer after being activated by open
air plasma were evaluated. Results showed that nylon textiles grafted with chitosan polymer had better antibacterial performances
than those grafted with chitosan oligomer. Air plasma activation at a higher speed (26 m/min) for a few times facilitated
the grafting of chitosan and critically determined the antibacterial activities. Further treatment with air plasma after grafting
improved the antibacterial effect. Overall, chitosan-grafted nylon textiles showed good antibacterial potential as well as
biocompatibility. 相似文献
352.
One new sterol, crassarosterol A (1), and four new steroidal glycosides, crassarosterosides A-D (2-5) were isolated from the Formosan soft coral Sinularia crassa. The absolute configuration of 1 was determined using the Mosher's method. The absolute configurations for the sugar moieties of 2-5 were determined by HPLC analysis on the o-tolylthiocarbamates derived from the liberated sugar after acid hydrolysis. Compounds 2 and 4 could significantly inhibit the expression of pro-inflammatory iNOS protein at 10 μM. In contrast, 1-3 were found to stimulate the expression of COX-2 protein at this concentration. Steroids 1 and 4 also showed cytotoxicity toward the selected human liver cancer cells. 相似文献
353.
Shiang-Jen Wu Ya-Wen Chiueh Ho-Cheng Lien Chih-Tsung Hsu 《Paddy and Water Environment》2015,13(4):391-404
This study proposes a risk analysis model for the rice production due to climate change in terms of agro-climate indices (i.e., cumulative temperature anomaly, cumulative precipitation anomaly, cumulative sunlight anomaly, cumulative radiation anomaly, and E1 Niño). This risk analysis model is developed by incorporating the multivariate Monte Carlo simulation method, multivariate regression equation, and uncertainty analysis method (advanced first-order second-moment, AFOSM). The study area is composed of 15 counties/cities in Taiwan, East Asia. The data set for the model development and applicability contains 27 years of annual rice productions and agro-climate indices in addition to cultivation areas. Through the proposed risk analysis model, it can be seen that the rice production in Taiwan is especially sensitive to temperature, precipitation, and sunlight. Also, on average, improving performance by reducing insufficient rice risk can rise by 80 % when the rice production increases from 3 × 104 to 3 × 105 tons. 相似文献
354.
355.
Persian-related and non-Persian-related cats were examined by ultrasonography and/or molecular testing to determine the prevalence of feline polycystic kidney disease (PKD) and the presence of a PKD1 gene mutation. PCR was used to amplify exon 29 of the PKD1 gene using genomic DNA extracted from blood samples, and the PCR products were analysed by direct DNA sequencing. Among the 111 cats included in the study, 54 were examined by both ultrasonography and gene testing for a point mutation in exon 29 of the PKD1 gene. The prevalence of PKD diagnosed by ultrasonography was 25.9 per cent in all the cats and 24.2 per cent in Persian-related cats. The prevalence of the transversion mutation in exon 29 of the PKD1 gene was 13.5 per cent in all cats and 15.7 per cent in Persian-related cats. Three cats that were diagnosed with PKD by ultrasonography did not have the mutation within exon 29. Nucleotide analysis of exon 29 indicated that male cats had a higher point mutation rate than female cats. 相似文献
356.
Evaluation of the Ph‐3 gene‐specific marker developed for marker‐assisted selection of late blight‐resistant tomato
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Ya‐Ying Wang Chien‐Hua Chen Annika Hoffmann Yun‐Che Hsu Shu‐Fen Lu Jaw‐Fen Wang Peter Hanson 《Plant Breeding》2016,135(5):636-642
Late blight caused by Phytophthora infestans is one of the most destructive diseases of tomato (Solanum lycopersicum L.) that mainly occurs in cool and wet environments. With the spread of the A2 mating type and new clonal lineages, fewer fungicides provide effective control of the disease, which has increased its worldwide threat. Host resistance could contribute significantly to sustainable disease control. Ph‐3 is a race‐specific late blight resistance gene commonly used in commercial tomato breeding. Availability of precise and easy to use gene‐based markers would facilitate selection. In this study, a Ph‐3 on‐gene cleaved amplified polymorphic sequence (CAPS) marker, Ph3.gsm/HincII, was developed based on the published gene sequence of Ph‐3. The effectiveness of the marker was evaluated along with other published Ph‐3 markers using an F9 recombinant inbred line (RIL) population derived from NC 23E‐2(93) × L3708. Markers Ph3.gsm/HincII and TG328/BstNI accurately genotyped the RIL population for Ph‐3. In addition, Ph3.gsm/HincII was able to differentiate variable susceptible alleles. This reliable codominant DNA marker would be very useful in marker‐assisted selection, particularly for resistance gene pyramiding. 相似文献
357.
Manipulation of nitrogen digestion by sheep using defaunation and various nitrogen supplementation regimens 总被引:4,自引:0,他引:4
Five ruminally, duodenally, and ileally cannulated sheep (average BW 62 kg) were fed 65% roughage: 35% concentrate diets (CP = 15%) in a 5 x 5 Latin square design to study the applicability of using a combination of defaunation with N supplements (soybean meal [SBM], corn gluten meal [CGM], blood meal [BM], urea, and casein) with different extents of ruminal degradation to manipulate microbial protein synthesis and amount of ruminal escape protein. Diets were fed twice daily (1,759 g DM/d). Defaunation was accomplished with 30-ml doses of alkanate 3SL3 (active ingredient: sodium lauryl diethoxy sulfate)/sheep daily for 3 d with 2 d of fasting. Treatment 1 (control) involved feeding faunated sheep a diet in which the supplemental N (45% of total dietary N) was 67% SBM N and 33% urea N. Treatment 2 involved feeding defaunated sheep the same diet as the control. Treatments 3, 4, and 5 involved feeding defaunated sheep diets in which the supplemental N source was either 67% CGM-BM (1:1 N ratio) N:33% urea N, or 33% CGM-BM N:67% urea N or 33% CGM-BM N:33% urea N:33% casein N, respectively. Compared with the faunated control, defaunation decreased (P less than .05) ruminal ammonia concentration (19 vs 26 mg/dl) and increased (P less than .05) CP flow to the duodenum (253 vs 214 g/d) due to a trend for increases in both bacterial (BCP) and nonbacterial (NBCP) CP flows.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
358.
Effects of defaunation and various nitrogen supplementation regimens on microbial numbers and activity in the rumen of sheep 总被引:5,自引:0,他引:5
Five sheep (average BW 62 kg) were fed 65% roughage: 35% concentrate diets (CP = 15%) in a 5 x 5 Latin square design to study the effects of combinations of defaunation and N supplements (soybean meal [SBM], corn gluten meal [CGM], blood meal [BM], urea, and casein) differing in ruminal degradation on ruminal microbial numbers and activity. Diets were fed twice daily (DM intake 1,759 g/d). Defaunation was accomplished with doses of 30 ml of alkanate 3SL3.sheep-1.d-1 for 3 d with 2 d of fasting. Treatment 1 (control) involved feeding faunated sheep a diet in which the supplemental N was 67% SBM N and 33% urea N. Treatment 2 involved feeding defaunated sheep the same diet as the control. Treatments 3, 4, and 5 involved feeding defaunated sheep diets in which the supplemental N source was either 67% CGM-BM N (CGM and BM combined on a 1:1 N ratio): 33% urea N, or 33% CGM-BM N:67% urea N or 33% CGM-BM N:33% urea N:33% casein N, respectively. Compared with the faunated control, defaunation (Treatments 2, 3, 4, and 5) increased (P less than .05) total direct counts of ruminal bacteria (2.7 vs 1.3 x 10(11)/ml), fungal zoospores (2.8 vs 1.4 x 10(5)/ml), and ruminal microbial protease activity (1.4 vs 1.0 mg azocasein/[ml ruminal fluid.h]). Defaunation did not have a consistent effect on ruminal microbial deaminase activity. Compared with the control, defaunation resulted in lower (P less than .05) total perchloric acid-soluble amino N in ruminal fluid at 4 and 10 h after the morning feeding. Defaunation did not decrease (P greater than .05) total free amino acid concentrations in ruminal fluid, but it altered the profile of free amino acids. Although defaunation increased (P less than .05) ruminal bacterial numbers, no increases in total microbial CP or OM concentrations in ruminal contents were observed. 相似文献
359.
360.
Avian reovirus (ARV) causes viral arthritis, chronic respiratory diseases, and malabsorption syndrome. The P10 protein is a viroporin and induces cell fusion, whereas the biological function of P17 protein is completely unknown. In this study, the nucleotide sequences of the P10- and P17-encoding genes from 17 field isolates and vaccine strains of ARV isolated over a 23-year period from distinct geographic locations were analyzed to define phylogenetic profiles and to study sequence variability and genetic evolution. These genes displayed the signs of a high level of sequence divergence and have evolved into five distinct lineages, respectively. The P17-encoding gene showed higher sequence divergence than that of P10-encoding gene. Our results indicated that synonymous substitutions predominate over nonsynonymous substitutions in both genes. Comparison of P10 and P17 gene phylograms with those of S-class genes revealed distinct evolutionary patterns, indicating that P10 and P17 evolve in an independent manner. Comparative sequence analysis also showed extensive sequence divergence between ARV and other orthoreoviruses. The phylogenetic analysis of P10- and P17-encoding genes revealed that diversity within both genes is neither dependent of viral serotypes nor correlated with the disease states caused by avian reovirus. 相似文献