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111.
Effects of live coral,epilithic algal communities and substrate type on algal recruitment 总被引:1,自引:1,他引:0
The recruitment of algae is a critical process during algal colonization and invasions, including coral-to-algal phase shifts. Although algae are widely assumed to colonize and kill corals, there is very little known about the recruitment dynamics of coral reef algae. This study tested the ability of two dominant macroalgae (Fucales including
Sargassum spp. and Lobophora variegata) to settle and grow on healthy coral tissue. The study also explored the effects of interactions with prior occupants, and of abiotic substrate properties (texture, and ceramic and carbonate material). The results indicate that healthy corals were able to prevent attachment or survival of recruits of these macroalgae. This is a significant point, since it suggests that the replacement of corals by algae may often require prior stress or death in the coral tissue. Pre-conditioning of plates at different sites had some effects, but these were relatively minor, whereas there was considerable variation within sites. Some of this variation appeared to be related to the amount of turf algae or crustose coralline algae on the plates. Recruitment was generally, but not always, higher on plates with rougher texture. Overall, this preliminary exploration indicates considerable potential for variability in outcomes of algal colonization, with implications for the dynamics of algal invasions. In particular, the results do not support suggestions that planktonic algal propagules can directly settle on and colonize healthy coral tissue.Communicated by Topic Editor D. Barnes 相似文献
112.
The female of Ixodes neuquenensis Ringuelet, 1947 (Acari: Ixodidae) is redescribed and the nymph and larva are described from specimens collected from the endangered marsupial Dromiciops gliroides Thomas (Microbiotheria: Microbiotheriidae) in Argentina. At first sight the female of I. neuquenensis resembles a member of the subgenus Ixodes Latreille, 1795. However, the female of I. neuquenensis is peculiar in having the combination of two spurs on coxae II-IV and a pair of chitinous plaques internal to coxa I. Both the nymph and larva have an anterior and posterior process on palpal article I, characteristics of the subgenus Ixodiopsis Filippova, 1957 and some representatives of the subgenus Pholeoixodes Schulze, 1942. Analysis of 16S mitochondrial rDNA sequences showed no strong relationship with any known Ixodes subgenus. 相似文献
113.
Valle MR Mèndez L Valdez M Redondo M Espinosa CM Vargas M Cruz RL Barrios HP Seoane G Ramirez ES Boue O Vigil JL Machado H Nordelo CB Piñeiro MJ 《Experimental & applied acarology》2004,34(3-4):375-382
Boophilus microplus has developed resistance against a range of chemical acaricides which has stimulated the development of alternative methods such as vaccination against ticks. In Cuba, the Bm86-based recombinant vaccine GavacTM has been successfully used in a number of controlled laboratory and field trials in cattle against B. microplus. In this paper, we have evaluated GavacTM in a large scale field trial wherein 588,573 dairy cattle were vaccinated with the aim to reduce the number of acaricidal treatments. It was found that the number of acaricidal treatments could be reduced by 87% over a period of 8 years (1995–2003). Prior to the introduction of the vaccine, 54 clinical cases of babesiosis and six fatal cases were reported per 1000 animals. Six years later, the incidence of babesiosis was reduced to 1.9 cases per 1000 cattle and mortality reduced to 0.18 per 1000. The national consumption of acaricides in Cuba could be reduced by 82% after the implementation of the integrated anti-B. microplus control program. 相似文献
114.
Vidotto V Pontón J Aoki S Quindós G Mantoan B Pugliese A Ito-Kuwa S Nakamura K 《Revista iberoamericana de micología》2004,21(2):70-74
Twenty-six Candida dubliniensis and 27 Candida albicans oral strains isolated from patients infected by the human immunodeficiency virus (HIV) were tested for germ tube production and 21 extracellular enzymatic activities. Assessment of the enzymatic profile was performed by using the API-ZYM commercial kit system (bioMerieux, France), which tests 19 different enzymes. Protease activity was expressed during the first days of incubation by 100% of the strains studied and resulted higher than phospholipase activity in the C. dubliniensis and C. albicans strains tested. The API-ZYM profile of the C. dubliniensis and C. albicans strains differs with respect to the number and percentage of the enzymes considered, as well as with the intensity of the substrate metabolized by the strains, in particular for the enzymes n 8 (cystine-arylamidase), n 12 (naphtol-AS-BI-phosphohydrolase) and n 16 (alpha-glucosidase). These enzymes may be useful to differentiate C. dubliniensis and C. albicans together with other phenotypic characteristics proposed in the literature. No relationship among protease, phospholipase and other extracellular enzymatic activities was observed in C. dubliniensis. The average percentage of strains filamentation after 4 h was between 32 and 42%. 相似文献
115.
During the last decades, the use of antibody tests for the diagnosis of invasive mycoses has declined as a consequence of the general belief that they are insensitive and non-specific. However, there is a clear evidence that antibodies can be detected in highly immunodeficient patients (such as bone marrow transplant recipients), and that those antibodies are useful for the diagnosis. Antibody tests are currently in use as diagnostic tools for some primary mycoses, such as the endemic mycoses, aspergilloma, allergic bronchopulmonary aspergilosis and sporothrichosis. For invasive candidiasis, diagnostic methods must differentiate Candida colonization of mucous membranes or superficial infection from tissue invasion by this microorganism. Substantial progress has been made in diagnosis of invasive candidiasis with the development of a variety of methods for the detection of antibodies and antigens. However, no single test has found widespread clinical use and there is a consensus that diagnosis based on a single specimen lacks sensitivity. It is necessary to test sequential samples taken while the patient is at greatest risk for developing invasive candidiasis to optimize the diagnosis. Results obtained from a panel of diagnostic tests in association with clinical aspects will likely be the most useful strategy for early diagnosis and therapy. 相似文献
116.
Pérez AJ Perez-Iratxeta C Bork P Thode G Andrade MA 《Bioinformatics (Oxford, England)》2004,20(13):2084-2091
117.
Tubio G Nerli B Picó G 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2004,799(2):293-301
In order to develop possible correlations to predict partioning behaviour of proteins, five mammalian albumins (goat, bovine, equine, human and pig ones) with similar physico-chemical properties (molecular mass and isoelectrical point) were chosen. Evaluation of the relationship between hydrophobicity and partitioning coefficient (Kr) in polyethylenglycol-dextran (PEG-DxT500) systems formed by polyethyleneglycols of different molecular mass (3350, 6000 and 10,000) was investigated by estimating relative surface hydrophobicity (So) with a fluorescent probe, 1 anilino-8-naphthalene sulfonate. No relationship between Kr and So was found for systems formed by PEG3350, while aqueous two-phase systems with PEG6000 and PEG10,000 gave better correlations. The results obtained may be explained on the basis of an increase in the interaction between the latter PEGs and the protein due to their higher hydrophobic character which increases as the PEG molecular mass does so. In this way, systems with PEGs of higher molecular mass give the highest resolution to exploit hydrophobicity in partitioning. 相似文献
118.
Enantiomerically pure compounds as precursors for the synthesis of hydroxylated derivatives of artemisinin/arteether have been prepared from (+)-(S)-carvone and (+)-car-2-ene. 相似文献
119.
120.
Lymphatic vasculature development 总被引:1,自引:0,他引:1
Oliver G 《Nature reviews. Immunology》2004,4(1):35-45
Although the process of blood vasculature formation has been well documented, little is known about lymphatic vasculature development, despite its importance in normal and pathological conditions. The lack of specific lymphatic markers has hampered progress in this field. However, the recent identification of genes that participate in the formation of the lymphatic vasculature denotes the beginning of a new era in which better diagnoses and therapeutic treatment(s) of lymphatic disorders could become a reachable goal. 相似文献