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In traditional medical practice, the larvae of some Diptera: Calliphoridae, notably Lucilia illustris (Meigen), L.sericata (Meigen) and Phormia regina (Meigen), have been employed for maggot therapy, i.e. to help clean lesions antiseptically, especially for treatment of chronic osteomyelitis. This mode of treatment remains appropriate for cases where antibiotics are ineffective and surgery impracticable.  相似文献   
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An overview of the basic principles of photochemistry is presented to facilitate discussion of fluorescence, quenching and quantum yields. These topics in turn provide the foundation for an account of fluorescence spectroscopy and its application to microscopy. A brief overview of light microscopy and the application of fluorescence microscopy is given. The influences of molecular features, such as aromatic character and substitution patterns, on color and fluorescence are described. The concept of color fading is considered with particular reference to its effect on microscopic preparations. A survey of representative fluorescent probes is provided, and their sensitivity, application, and limitations are described. The phototoxicity of fluorescent molecules is discussed using biomembranes and DNA as examples of targets of toxicity. Photodynamic therapy, a relatively new clinical application of phototoxicity, is described. Both anticancer and antimicrobial applications are noted, and an assessment is given of the current ideas on the ideal physicochemical properties of the sensitizing agents for such applications.  相似文献   
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SYNOPSIS. We report results of a three year comparative laboratorystudy of kin recognition abilities in Arctic ground squirrels(Spermophilus parryii) and Belding's ground squirrels (S. beldingi),and a field investigation of kin recognition in S. beldingi.Our laboratory work shows that in both species, preweaned pupsreared together, whether they are biological siblings or cross-fostered(unrelated) nestmates, are equally aggressive in subsequentpaired arena tests. Thus, pups that share a natal nest are treatedlike siblings. Among pups reared apart, sister-sister pairsare less aggressive in arena tests than are pairs of nonkinfemales, whereas relatedness does not affect male-male or male-femaleaggression. Thus both relatedness and rearing environment mediaterecognition among female S. parryii and S. beldingi. In free-livingBelding's ground squirrels at Tioga Pass, California, dam-offspringand sister-sister recognition apparently first occur at weaning,coincident with aboveground emergence of juveniles. Most intriguing(electrophoretically identified) littermate full-sisters andmaternal half-sisters, which result from multiple mating byfemales, seem to treat each other differently despite havingshared a natal nest. The full-sisters are less agonistic andmore cooperative than the half-sisters. In interpreting theselaboratory and field results, we explore four proximal mechanismsby which kin might be identified, including one in which recognitionis based on (learned) phenotypic similarity to an individual'snestmates or itself (phenotype matching). Our data and thoseof several recent investigators of recognition in other taxaimplicate both association with relatives and phenotype matchingin the ontogeny of kin recognition.  相似文献   
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Plasmodium lophurae-infected red blood cells utilized considerably greater quantities of glucose than did uninfected duckling red cells. Kinetic analysis of glucose transport showed: (A). Below a concentration of 2 mM in the medium the uptake process followed Michaelis-Menten kinetics (carrier-mediated facilitated diffusion) whereas at concentrations greater than this simple diffusion became the main mode of entry. (B). The apparent transport constants, Kt, for normal and infected cells were similar. However there was an 8-fold increase in the maximal velocity, Vmax, for infected cells. (C). “Free” malaria parasites had a significantly lower Kt and a higher Vmax than did normal or infected red cells. Entry and exit studies with the nonmetabolizable sugar analog, 3-0-methyl glucose, demonstrated that the enhanced rate of uptake by infected cells involved an increase in the simple diffusion component and the degree of enhancement was correlated with the size of the intracellular parasite. Competition experiments suggested that in the malaria-infected cell one locus is involved in the carrier-mediated transport of glucose, mannose and galactose whereas another locus transports fructose and/or glycerol. These results indicate that the enhanced entry of glucose into the malaria-infected red cell is a consequence of factors other than increased glucose catabolism by the host-parasite complex, and the host cell's capacity to take up greater quantities of sugar directly involves the growing intracellular plasmodium.  相似文献   
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The histological effect on and stress response of post juvenile Clarias gariepinus exposed to Qua Iboe crude oil and rig wash were investigated. Fish weighing 60–90 g and measuring 16–18 cm were exposed for 7–28 days to 8.00 ml?1 Qua Iboe crude oil and 0.0018 ml–1 rig wash, both being 0.1 of the 96 hr LC50. Blood samples of C. gariepinus were collected every seven days and evaluated for stress by measuring cortisol concentration. The gills and liver were studied and scored for Gill Alteration Index (GAI) and Hepatic Alteration Index (HAI), respectively. There was an increase in cortisol level up to the 7th and 14th day among the group exposed to Qua Iboe crude oil, with a decrease on the 21st and 28th day. The rig wash group increased in cortisol level up to the 7th day and decreased slightly on the 14th day, after which the trend became irregular. The toxic effects of the Qua Iboe crude oil and rig wash were time dependent, as shown by the histopathological alteration index (HAI) of gill and liver. After 28 days of exposure, the gills had irreparable damage due to high frequency of cellular necrosis and degeneration, whereas the liver had from moderate to severe damage due to the high frequency of cellular degeneration and inflammation. Qua Iboe crude oil and rig wash are both toxic to C. gariepinus, therefore their indiscriminate discharge to the environment must be discouraged.  相似文献   
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