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21.
Gen-Hong Wang Chun Liu Qing-You Xia Xing-Fu Zha Jie Chen Liang Jiang 《Insect Science》2008,15(3):201-208
22.
Eric Cundliffe 《Journal of industrial microbiology & biotechnology》1991,7(3):157-161
Originally presented as an Invited Lecture at the 1990 Society for Industrial Microbiology Annual Meeting in Orlando, Florida. 相似文献
23.
N. Dincer, S. Balci, A. Yazgan, G. Guney, R. Ersoy, B. Cakir and G. Guler Follow‐up of atypia and follicular lesions of undetermined significance in thyroid fine needle aspiration cytology Objective: To report our experience of atypia of undetermined significance (AUS)/follicular lesion of undetermined significance (FLUS) rate and outcome. Methods: Among 7658 patients with 19 569 nodules, 524 (2.7%) nodules were diagnosed as AUS/FLUS on fine needle aspiration (FNA). After exclusion of patients with simultaneous nodules that were suspicious for follicular neoplasm or malignancy or that were malignant, 368 (4.8%) patients were diagnosed as AUS/FLUS. The outcome of 146 patients who had undergone surgery or repeated fine needle aspirate at the time of preparation of this study was evaluated. The original FNAs were matched to repeated FNAs and thyroidectomy or diagnostic lobectomy specimens. Results: Seventy‐two (19.6%) of the 368 patients had directly undergone surgery, either a lobectomy or a thyroidectomy: of these, 27 (37.5%) had neoplastic nodules (21 were malignant). Seventy‐four (20.1%) of the 368 patients had repeat FNA. On second FNA, 47 of 74 (63.5%) were benign, three were suspicious for follicular neoplasm, one was malignant and 23 (31.1%) were non‐diagnostic. Four patients had a third FNA: two were AUS/FLUS, one was malignant and one non‐diagnostic. One patient had a fourth FNA, which was diagnosed as AUS/FLUS. Sixteen (21.6%) of 74 patients with repeat FNA had surgery: three of these had neoplastic nodules (two were malignant). Overall, 88 of the 368 (23.9%) patients had a thyroidectomy of which 30 (34.1%) were neoplastic and 23 (26.1%) malignant. The neoplastic rate for patients who were once diagnosed with AUS/FLUS was 8.2% and the malignancy rate 6.3%. The malignancy rate for patients on follow‐up at the time we prepared the study was 15.7% (23/146); 222 remained on follow‐up without surgery or repeat FNA or were managed elsewhere. Conclusions: Although in this category repeat FNA is expected rather than excision, we suggest evaluation of all AUS/FLUS patients in multidisciplinary meetings to decide management and recommend follow‐up of all patients with this diagnosis. 相似文献
24.
Abstract 1. Most ants are more like plants and marine invertebrates than other insects because the adults are sessile and the immature stages are motile. 2. This paper reported the results from a field experiment that increased food levels on the fungus gardening ant, Trachymyrmex septentrionalis, which has served as a model system for understanding the complexities of these obligate mutualisms. 3. Food supplementation increased the growth of the symbiotic fungus and this led to an increase in the amount of fungal biomass. The amount of fungal biomass was generally more important in determining the amount of ant offspring than colony size. 4. The results indicate that the population is food limited and colonies may compete for relatively rare fungal substrate. However, competition in this species is not obvious. 相似文献
25.
Aims: To analyse the effect of cell‐associated peptidases in yogurt starter culture strains Lactobacillus delbrueckii ssp. bulgaricus (LB) and Streptococcus thermophilus (ST) on milk‐protein‐based antimicrobial and hypotensive peptides in order to determine their survival in yogurt‐type dairy foods. Methods and Results: The 11mer antimicrobial and 12mer hypotensive milk‐protein‐derived peptides were incubated with mid‐log cells of LB and ST, which are required for yogurt production. Incubations were performed at pH 4·5 and 7·0, and samples removed at various time points were analysed by reversed‐phase high‐performance liquid chromatography (RP‐HPLC). The peptides remained mostly intact at pH 4·5 in the presence of ST strains and moderately digested by exposure to LB cells. Peptide loss occurred more rapidly and was more extensive after incubation at pH 7·0. Conclusions: The 11mer and 12mer bioactive peptides may be added at the end of the yogurt‐making process when the pH level has dropped to 4·5, limiting the overall extent of proteolysis. Significance and Impact of the Study: The results show the feasibility of using milk‐protein‐based antimicrobial and hypotensive peptides as food supplements to improve the health‐promoting qualities of liquid and semi‐solid dairy foods prepared by the yogurt fermentation process. 相似文献
26.
Broad genome‐wide testing is increasingly finding its way to the public through the online direct‐to‐consumer marketing of so‐called personal genome tests. Personal genome tests estimate genetic susceptibilities to multiple diseases and other phenotypic traits simultaneously. Providers commonly make use of Terms of Service agreements rather than informed consent procedures. However, to protect consumers from the potential physical, psychological and social harms associated with personal genome testing and to promote autonomous decision‐making with regard to the testing offer, we argue that current practices of information provision are insufficient and that there is a place – and a need – for informed consent in personal genome testing, also when it is offered commercially. The increasing quantity, complexity and diversity of most testing offers, however, pose challenges for information provision and informed consent. Both specific and generic models for informed consent fail to meet its moral aims when applied to personal genome testing. Consumers should be enabled to know the limitations, risks and implications of personal genome testing and should be given control over the genetic information they do or do not wish to obtain. We present the outline of a new model for informed consent which can meet both the norm of providing sufficient information and the norm of providing understandable information. The model can be used for personal genome testing, but will also be applicable to other, future forms of broad genetic testing or screening in commercial and clinical settings. 相似文献
27.
Bismuto E Martelli PL Casadio R Irace G 《Protein science : a publication of the Protein Society》2000,9(9):1730-1742
A molecular dynamics simulation approach has been utilized to understand the unusual fluorescence emission decay observed for beta-glycosidase from the hyperthermophilic bacterium Solfolobus sulfotaricus (Sbeta gly), a tetrameric enzyme containing 17 tryptophanyl residues for each subunit. The tryptophanyl emission decay of Sbeta gly results from a bimodal distribution of fluorescence lifetimes with a short-lived component centered at 2.5 ns and a long-lived one at 7.4 ns (Bismuto E, Nucci R, Rossi M, Irace G, 1999, Proteins 27:71-79). From the examination of the trajectories of the side chains capable of causing intramolecular quenching for each tryptophan microenvironment and using a modified Stern-Volmer model for the emission quenching processes, we calculated the fluorescence lifetime for each tryptophanyl residue of Sbeta gly at two different temperatures, i.e., 300 and 365 K. The highest temperature was chosen because in this condition Sbeta gly evidences a maximum in its catalytic activity and is stable for a very long time. The calculated lifetime distributions overlap those experimentally determined. Moreover, the majority of trytptophanyl residues having longer lifetimes correspond to those originally identified by inspection of the crystallographic structure. The tryptophanyl lifetimes appear to be a complex function of several variables, such as microenvironment viscosity, solvent accessibility, the chemical structure of quencher side chains, and side-chain dynamics. The lifetime calculation by MD simulation can be used to validate a predicted structure by comparing the theoretical data with the experimental fluorescence decay results. 相似文献
28.
Dr. Ernst Reiss Dr. Inge Weber Dr. Wolf-Dieter Ostermann 《Archives Of Phytopathology And Plant Protection》2013,46(4):353-355
Es wurde die Intra‐ und Interpopulationsvariation untersucht, die durch Adaptationsreaktionen der Individuen (Klone) der Gemeinen Quecke (Elytrigia repens (L.) DESV.) am Versuchsort zum Ausdruck kommt. Die Klone stammten aus Populationen verschiedener Höhenlagen vom Territorium der östlichen Bundesländer Deutschlands. Die Ergebnisse zeigen, daß sich die Populationen in der Variabilität der Enzymaktivität (saure Phosphatase, Peroxidase, Polyphenoloxidase) sowie in der Variabilität der Isoenzymmuster (Peroxidase, Esterase) unterscheiden. Die höchste Variabilität der genannten Parameter wurde für Populationen nachgewiesen, die aus einer Höhenlage von ca. 400 m ü. NN stammten. Ausgehend von 400 m ü. NN nimmt die Variabilität in Richtung größerer und niedrigerer Höhenlagen von 400 m hin ab. Die Variabilitätsunterschiede, die unter gleichen Bedingungen nachgewiesen wurden, weisen auf die Existenz eines Zusammenhanges zwischen den typischen Adaptationsreaktionen von Populationen und der Gesamtheit der Selektionsfaktoren des natürlichen Milieus hin, von dem sie stammten. Es gibt einen Zusammenhang zwischen der nachgewiesenen Variabilität und der Überlebensrate nach einer Adaptationsdauer von fünf Jahren. 相似文献
29.
30.
Ferrero ME Blanco-Aguiar JA Lougheed SC Sánchez-Barbudo I De Nova PJ Villafuerte R Dávila JA 《Molecular ecology》2011,20(12):2628-2642
The Pleistocene climatic oscillations promoted the diversification in avian species during the last glacial period. The red‐legged partridge (Alectoris rufa, Family Phasianidae) has a large natural distribution extending from the Mediterranean to humid temperate zones. However, the genetic structure for this species is unknown. The present study investigates the phylogeography, genetic structure and demographic history of A. rufa across its distribution, employing both mitochondrial DNA control region sequences and nuclear microsatellite loci. Our results propose that this species was greatly affected by Pleistocene glaciations. The mismatch analyses suggest that the current populations resulted from post‐glacial expansion and subsequent differentiation resulting in five diagnosable genetic clusters: Southwestern, Central‐eastern, Northwestern, Balearic and French and Italian. Further, we found evidence of three glacial refugia within the currently recognized Iberian glacial refugium. The intraspecific structure revealed by both maternal and biparental phylogeographic analyses was not resolved in the phylogenetic analyses. Based on all considerations, we recommended that five management units be recognized. 相似文献