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1.
Plant Foods for Human Nutrition - Cancer is a preventable and treatable disease, however, the incidence rates are on the rise. Classical treatment modalities for cancer include surgery,...  相似文献   
2.
Riemerella anatipestifer is a gram-negative rod-shaped bacterium associated with epizootic infections in poultry. A total of 35 R. anatipestifer isolates including the type strain ATCC11845T, reference and field strains for 18 different serotypes were characterized by repetitive sequence based-PCR (rep-PCR) with outwardly-directed primers based on the repetitive extragenic palindromic (REP) consensus sequence. This technique was applied by using either extracted genomic DNA or preparation of whole bacterial cells harvested directly from plate cultures. Rep-PCR discriminated the R. anatipestifer isolates into 19 electrophoretic types. DNA fingerprints obtained from rep-PCR of extracted genomic DNA or from preparations of whole cells yielded comparable patterns. Substantial variation was seen among the rep-PCR fingerprints of different serotypes. Moreover, different polymorphisms of the rep-PCR fingerprints were evident among epidemiologically unrelated isolates of the same serotype. These results suggest the presence of repetitive extragenic palindromic-like elements within the genome of R. anatipestifer that can be used in some isolates to discriminate between different strains belonging to the same serotype. Rep-PCR may serve as a useful molecular tool for subtyping R. anatipestifer isolates for epidemiologic investigations. The whole cell procedure offers the advantage of ease of performance requiring only small quantities of cells.  相似文献   
3.
The extraordinary abundance of ants in tropical rainforest canopies has led to speculation that numerous arboreal ant taxa feed principally as "herbivores" of plant and insect exudates. Based on nitrogen (N) isotope ratios of plants, known herbivores, arthropod predators, and ants from Amazonia and Borneo, we find that many arboreal ant species obtain little N through predation and scavenging. Microsymbionts of ants and their hemipteran trophobionts might play key roles in the nutrition of taxa specializing on N-poor exudates. For plants, the combined costs of biotic defenses and herbivory by ants and tended Hemiptera are substantial, and forest losses to insect herbivores vastly exceed current estimates.  相似文献   
4.
We have identified the xenobiotic receptor CAR (constitutive androstane receptor) as a key regulator of acetaminophen metabolism and hepatotoxicity. Known CAR activators as well as high doses of acetaminophen induced expression of three acetaminophen-metabolizing enzymes in wild-type but not in CAR null mice, and the CAR null mice were resistant to acetaminophen toxicity. Inhibition of CAR activity by administration of the inverse agonist ligand androstanol 1 hour after acetaminophen treatment blocked hepatotoxicity in wild type but not in CAR null mice. These results suggest an innovative therapeutic approach for treating the adverse effects of acetaminophen and potentially other hepatotoxic agents.  相似文献   
5.
Jelly curd used for a popular summer drink in Taiwan is prepared by extracting the pericarpial portion of jelly fig (Ficus awkeotsang Makino) achenes. The two most abundant proteins found in jelly curd have been identified as a pectin methylesterase and a chitinase. A method was developed to purify the next abundant protein by 40% ammonium sulfate precipitation and flowing through Mono Q chromatography. In sodium dodecyl sulfate-polyacrylamide gel electrophoresis analyses, the purified protein migrated as a polypeptide of 20 kDa in the absence of beta-mercaptoethanol but split into a minor polypeptide of 20 kDa and a major polypeptide of 27 kDa in the presence of this reducing agent. Two cDNA fragments encoding precursor polypeptides of two putative thaumatin-like protein isoforms were obtained by polymerase chain reaction cloning and subsequently overexpressed in Escherichia coli to generate recombinant proteins for antibody preparations. Immunological detection and mass spectrometric analyses indicated that the two split polypeptides were thaumatin-like protein isoforms encoded by the two cloned cDNA fragments.  相似文献   
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观察了桑天牛成虫行为,初步研究了60Coγ射线对雄虫的辐射效应。研究结果表明:雄虫占60%,飞翔能力强寿命长,雌雄虫需在构、桑树上进行补充营养,交尾均不止1次,雌虫产卵量大;60Coγ射线对雄虫取食、活力、寿命、交尾及孵化幼虫,均有明显影响,雄虫不育剂量的上限为163.2Gγ。  相似文献   
8.
BACKGROUND: Identification of Bactrocera carambolae Drew and Hancock, B. papayae Drew and Hancock, B. tau Walker, B. latifrons Hendel, B. cucurbitae Coquillett, B. umbrosa Fabricius and B. caudata Fabricius would pose a problem if only a body part or an immature stage were available. Analysis of polymerase chain reaction–restriction fragment length polymorphism (PCR‐RFLP) of cytochrome oxidase I (COI) gene using primers COIR, COIF, UEA7 and UEA10 and restriction enzymes (MseI, RsaI and Alu1) was carried out. The banding profiles in the electrophoresis gel were analysed. RESULTS: The COI gene in six Bactrocera spp. was successfully amplified by COIR and COIF, as well as UEA7 and UEA10, while B. caudata was amplified successfully only by UEA primers. Using COI amplified PCR products and restriction enzymes, distinct banding profiles for B. tau, B. latifrons, B. cucurbitae and B. umbrosa were observed, but not for B. carambolae and B. papayae. However, using UEA7, UEA10 and RsaI, B. caudata could be identified, while B. carambolae and B. papayae might possibly be separated from one another. It was also shown that adult body parts or immature life stages of B. carambolae, B. papayae, B. latifrons and B. cucurbitae produced the same banding profiles as the adults. CONCLUSION: PCR‐RFLP analyses are able to identify positively five Bactrocera species, while B. papayae and B. carambolae might possibly be separated from one another, even if immature life stages or adult body parts are used. Copyright © 2009 Society of Chemical Industry  相似文献   
9.
Global mapping of the yeast genetic interaction network   总被引:1,自引:0,他引:1  
A genetic interaction network containing approximately 1000 genes and approximately 4000 interactions was mapped by crossing mutations in 132 different query genes into a set of approximately 4700 viable gene yeast deletion mutants and scoring the double mutant progeny for fitness defects. Network connectivity was predictive of function because interactions often occurred among functionally related genes, and similar patterns of interactions tended to identify components of the same pathway. The genetic network exhibited dense local neighborhoods; therefore, the position of a gene on a partially mapped network is predictive of other genetic interactions. Because digenic interactions are common in yeast, similar networks may underlie the complex genetics associated with inherited phenotypes in other organisms.  相似文献   
10.
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