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941.
The rheological changes in rice noodles by the substitution of corn bran and the effect of temperature on the xanthophyll content (lutein and zeaxanthin) of the corn bran-rice flour noodles were evaluated. The use of corn bran increased the water holding capacity of rice flour at room temperature while the opposite results were observed after heating. The pasting parameters of rice flour-corn bran mixture were reduced with increasing levels of corn bran and the mixture paste exhibited more dominant liquid-like behavior. The noodles containing corn bran exhibited lower expansion ratio and softer textural properties. The levels of lutein and zeaxanthin in raw corn bran were 336.9 and 123.1 μg/100 g, respectively and were significantly reduced (P < 0.05) by heating. While lutein and zeaxanthin were not detected in the control noodles without corn bran, their levels in corn bran-incorporated noodles ranged from 56.2 to 137.3 μg/100 g and from 37.9 to 61.9 μg/100 g, respectively and were significantly reduced by 37.7–45.4% (P < 0.05) after cooking. Thus, the heat-labile characteristics of two xanthophylls were clearly observed. This study provides useful information on the processing performance and xanthophyll content of corn bran, possibly extending its use in a wider variety of foods.  相似文献   
942.
Ma DD  Lee CS  Au FC  Tong SY  Lee ST 《Science (New York, N.Y.)》2003,299(5614):1874-1877
Small-diameter (1 to 7 nanometers) silicon nanowires (SiNWs) were prepared, and their surfaces were removed of oxide and terminated with hydrogen by a hydrofluoric acid dip. Scanning tunneling microscopy (STM) of these SiNWs, performed both in air and in ultrahigh vacuum, revealed atomically resolved images that can be interpreted as hydrogen-terminated Si (111)-(1 x 1) and Si (001)-(1 x 1) surfaces corresponding to SiH3 on Si (111) and SiH2 on Si (001), respectively. These hydrogen-terminated SiNW surfaces seem to be more oxidation-resistant than regular silicon wafer surfaces, because atomically resolved STM images of SiNWs were obtained in air after several days' exposure to the ambient environment. Scanning tunneling spectroscopy measurements were performed on the oxide-removed SiNWs and were used to evaluate the electronic energy gaps. The energy gaps were found to increase with decreasing SiNW diameter from 1.1 electron volts for 7 nanometers to 3.5 electron volts for 1.3 nanometers, in agreement with previous theoretical predictions.  相似文献   
943.
Journal of Crop Science and Biotechnology - The ionizing radiation methods, including X-rays, gamma rays, and neutrons to create variation is well established and used in major crops. Many...  相似文献   
944.
A nationwide investigation was performed to detect the presence of 1014 mutation(s) in voltage gated sodium channel (kdr) gene of Culex quinquefasciatus from 14 residential areas across 13 states and a federal territory in Malaysia. Molecular genotyping of kdr mutation was performed via a modified three tubes allele-specific-polymerase chain reaction (AS-PCR) and direct sequencing of kdr gene. Based on the results of AS-PCR, homozygous susceptible (SS) genotype was found in nine out of 14 populations with 38 individuals from a total sample size of 140. Heterozygous (RS) genotype was most predominant (99 individuals) and distributed across all study sites. Homozygous resistance (RR) genotype was detected in Perak (one individual) and Selangor (two individuals). The resistance kdr allele frequencies ranged from 0.1 to 0.55, with the highest being detected in Cx. quinquefasciatus population from Selangor. This study has documented the first field-evolved instance of 1014F mutation in Malaysian mosquitoes and the findings of this study could be utilized in the implementation of strategic measures in vector control programs in Malaysia.  相似文献   
945.
946.
947.
Disease resistance mediated by the resistance gene Xa21 is developmentally controlled in rice. We examined the relationship between Pathogenesis Related (PR) defense gene expression and Xa21-mediated developmental disease resistance induced by Xanthomonas oryzae pv. oryzae (Xoo). OsPR1a, OsPR1b, and OsPR1c genes were cloned and their induction was analyzed, in addition to the OsPR10a gene, at the juvenile and adult stages in response to a wildtype Xoo strain that induces a resistance response (incompatible interaction) and an isogenic mutant Xoo strain that does not (compatible interaction). We found that the adult stage leaves are more competent to express these OsPR1 genes and that the Xa21 locus is required for the highest levels of induction.  相似文献   
948.
Protoporphyrinogen oxidase (Protox) of Myxococcus xanthus (Mx Protox) is a 49-kDa membrane protein that catalyzes conversion of protoporphyrinogen IX (Protogen IX) into protoporphyrin IX (Proto IX). Upon heterologous expression in transgenic rice plants, Mx Protox is dually targeted into plastids and mitochondria, increasing resistance against the herbicidal Protox inhibitor oxyfluorfen. Here, we describe the chemical synthesis of the Mx Protox gene by assembling several small synthetic DNA fragments derived by ligation-PCR. Codon usage in the resulting 1416-bp gene was modified to correspond to that of the Arabidopsis Protox gene, a change that resulted in a decrease in G+C content from 71 to 49%. The modified Mx Protox gene was used to generate transgenic rice plants via Agrobacterium-mediated transformation. Integration, expression, and inheritance of the transgenes were demonstrated by Southern, Northern, and Western blot analyses. In plants transformed with the modified, low G+C-content Mx Protox gene, levels of Protox expression and enzyme activity were low compared to the levels observed for plants transformed with the native Mx Protox gene. Nonetheless, like the native gene, the modified gene conferred a high level of resistance to the herbicide oxyfluorfen in a seedling growth test.  相似文献   
949.
Rice dwarf virus isolates were collected from several locations in Japan, the Philippines, China, Nepal and Korea. Genomic dsRNA segment profiles in polyacrylamide gel electrophoresis differed among the isolates. There were less differences in the profiles between isolates from Japan and Korea than in those between these two Countries and others. Nucleic acid hybridization was used to examine the extent of genomic variation. Full-length cDNAs to all genomic segments encoding non-structural proteins (S4, S6, S9, S10, S11 and S12) were synthesized from two Japanese isolates, and were used for dot-blot hybridization. Hybridizations using probes generated from the full-length cDNA clones failed to differentiate isolates from different geographical areas. However, cDNA probes covering a variable region of S12 were able to distinguish Japanese and Korean isolates from those of other countries. Phylogenetic tree analysis based on the amino acid sequence of P12 encoded by S12 grouped Japanese and Korean isolates together. The Chinese isolates from two different locations (Yunnan and Fujian) were closely related to each other, and were the most distantly related to Japanese and Korean isolates.  相似文献   
950.

Objective

The aim of this study was to determine the incidence and the associated risk factors of peri-anaesthetic mortality and gastrointestinal complications in pet rabbits.

Study design

Retrospective cohort study.

Animals

A total of 185 pet rabbits admitted to the Exotic Referal Service of Beaumont Sainsbury’s Animal Hospital over the period 2009–2016.

Methods

The clinical records of the rabbits were obtained from the database. To evaluate the incidence of peri-anaesthetic mortality, three possible outcomes were considered: alive, dead or euthanized within the 72 hours following the anaesthetic event. Food intake and stool production during the first 72 hours following the anaesthetic event were evaluated to investigate the occurrence of gastrointestinal complications. Thereafter, various hypothesized risk factors, including administration of alpha-2 agonists, body weight, American Society of Anaesthesiologists classification and endotracheal intubation were tested against peri-anaesthetic mortality and gastrointestinal complications, with both univariate and multivariate binary logistic regression.

Results

Twenty-five out of 185 rabbits underwent two anaesthetic events; therefore, data from 210 cases were used. Of these 210 cases, six died during sedation or general anaesthesia and four (one of which euthanized) died during the first 72 postoperative hours, accounting for an actual mortality rate equal to 4.8% (95% confidence interval, 0.025–0.086). Peri-anaesthetic gastrointestinal complications developed in 77 (38%) out of the 204 anaesthetic events whose outcome was not intraoperative death (95% confidence interval, 0.314–0.446). Species-specific risk factors could not be identified for peri-anaesthetic mortality; however, the odds for post-anaesthetic gastrointestinal complications increased significantly with body weight (p = 0.01).

Conclusions and clinical relevance

Our findings confirm that rabbits continue to have a higher incidence of peri-anaesthetic mortality than dogs and cats, and highlight a high risk for nonfatal peri-anaesthetic gastrointestinal complications in this species.  相似文献   
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