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991.
‘Immunocompetence’ is a term used in avian immunological ecology to refer to the ability of an individual to overcome potential parasite infections. However, there are multiple ecological definitions of this term currently used and all of them are rather liberal in immunological terms. This prevents much of the potential intellectual interchange between avian ecologists and immunologists, which decelerates the development of immunological ecology as a scientific discipline. We therefore highlight that the term should be handled with care. In any individual host‐parasite interrelationship the demands on host immunity are distinct and thus also the measurements of immunity in any particular case should be aimed differently. Although ornithologists often aspire to obtain a single variable for immunity in their research, due to the enormous diversity of parasites possessing the ability to infect the host, there is no single value for anti‐parasite resistance, i.e. no overall ‘immunocompetence’ per se exists. We propose to use more rigorous terminology, consistent with the one used in classical immunology. The term ‘immunocompetence’ (defined as the ability to produce anti‐parasite or anti‐antigen immune response) should be used as 0/1 character. The magnitude of a particular immune response (i.e. a continuous quantitative trait) should be referred to as ‘immune responsiveness’. Most importantly, both terms should always be used only with respect to a certain parasite taxon or antigen studied as otherwise they lose their explanatory value. 相似文献
992.
R. P. George R. M. Albrecht K. B. Raper I. B. Sachs A. P. MacKenzie 《Journal of bacteriology》1972,112(3):1383-1386
The ellipsoidal dormant spores of Dictyostelium dicoideum prepared by freeze-drying had a uniform, compact appearance with fine wrinkles or ridges on the surface. Swollen spores were uneven in appearance, without fine wrinkles but with a seemingly expanded surface covering. The surfaces of the postgermination spore husks appeared unaltered except for a single straight exit slit along the longitudinal plane. 相似文献
993.
Engin Karabudak Wendel Wohlleben Helmut Cölfen 《European biophysics journal : EBJ》2010,39(3):397-403
A multiwavelength UV/vis detector for the analytical ultracentrifuge (MWL-AUC) has been developed recently. In this work,
β-carotene–gelatin composite particles are investigated with MWL-AUC. Band centrifugation with a Vinograd cell is used to
ensure maximum sample separation. Spectral changes of the system are observed in dependence of the sedimentation coefficient
and are attributed to a previously unknown inhomogeneity of the β-carotene chemical composition with both H- and J-aggregates
coexisting in a mixture. In addition, our data suggest that pure H- and J-aggregates exist in a particle while their relative
concentrations in a mixture determine the color characteristics of the sample. The unique abilities and properties of MWL-AUC
include sedimentation coefficient distributions for all possible wavelengths, full UV/vis spectra of each different species
in the mixture and 3D movies of the sedimentation process. These properties significantly extend the scope of the analytical
ultracentrifuge technique and show that complex biopolymer multicomponent mixtures can be resolved into their individual species. 相似文献
994.
Roney de Carvalho Nicolato Raquel Trópia de Abreu Bruno Mendes Roatt Rodrigo Dian de Oliveira Aguiar-Soares Levi Eduardo Soares Reis Maria das Gra?as Carvalho Cláudia Martins Carneiro Rodolfo Cordeiro Giunchetti Leoneide Erica Maduro Bouillet Denise Silveira Lemos Wendel Coura-Vital Alexandre Barbosa Reis 《PloS one》2013,8(12)
Hematological analysis has limited applications for disease diagnosis in Leishmania infantum–infected dogs, but it can be very important in evaluating the clinical forms of the disease and in understanding the evolution of canine visceral leishmaniasis (CVL) pathogenesis. Recently, we demonstrated that alterations in leucopoiesis and erythropoiesis are related to clinical status and bone marrow parasite density in dogs naturally infected by L. infantum. To further characterize these alterations, we evaluated the association between the hematological parameters in bone marrow and peripheral blood alterations in groups of L. infantum–infected dogs: asymptomatic I (AD-I: serum negative/PCR+), asymptomatic II (AD-II: serum positive), oligosymptomatic (OD), and symptomatic (SD). Results were compared with those from noninfected dogs (NID). The SD group was found to present a decrease in erythropoietic lineage with concomitant reductions in erythrocytes, hemoglobin, and hematocrit parameters, resulting in anemia. The SD group also had increased neutrophils and precursors and decreased band eosinophils and eosinophils, leading to peripheral blood leucopenia. In the AD-II group, lymphocytosis occurred in both the peripheral blood and the bone marrow compartments. The SD group exhibited lymphocytosis in the bone marrow, with lymphopenia in the peripheral blood. In contrast, the AD-I group, showed no significant changes suggestive of CVL, presenting normal counts in bone marrow and peripheral blood. Our results showed for the first time that important changes in hematopoiesis and hematological parameters occur during ongoing CVL in naturally infected dogs, mainly in symptomatic disease. Taken together, our results based on myelogram and hemogram parameters enable better understanding of the pathogenesis of the anemia, lymphocytosis, and lymphopenia, as well as the leucopenia (eosinopenia and monocytopenia), that contribute to CVL prognosis. 相似文献
995.
996.
Ali Khalil Raymonde Baltenweck-Guyot Rubén Ocampo-Torres Pierre Albrecht 《Phytochemistry letters》2010,3(2):93-95
Polyphenols are widespread components of higher plants. Sorghum is rich in polyphenols and known to contain a specific type, 3-deoxyanthocyanins, many of which remain uncharacterised. Here we report the structural determination of a new pigment isolated from red Sorghum bicolor var. bicolor (Moench) and characterised as 8-hydroxy-2-(4′-hydroxyphenyl)-5-(4″-hydroxyphenyl)-pyrano[4,3,2-de]1-benzopyrylium by MS, UV–vis and 2D NMR spectroscopy. This new symmetrical pyrano-3-deoxyanthocyanidin, containing apigeninidin as a base unit, displays structural features responsible for higher stability as compared to corresponding anthocyanins. 相似文献
997.
This forum addresses the emerging Prison Reentry Industry (PRI). It features articles and essays from authors on three continents, and from a variety of perspectives. The authors included here range from ex-prisoners and current prisoners, PRI workers and activists, former prisoners now involved in academic and policy research, critics and practitioners. Together these essays mark a first effort to bring a number of perspectives to bear on a growing and already vast array of programs, in the United States and beyond. From these perspectives, the hope is that the criticism brought forward here will help stimulate debate and reform in future discussions about a processes that affect the lives of millions of people world-wide. 相似文献
998.
999.
1000.
Joachim Venus Frank Idler Christine Albrecht 《Applied microbiology and biotechnology》1992,37(2):240-243
Summary Illustrated by the selection of lactic acid bacteria to be used as biological ensilage agents, new methods are introduced; they are practicable in microtitre plate dimensions by means of an automatic analysing system. According to the test setting, statements can be made on the acidifiability, the inhibition effect on contaminants and the growth under different milieu conditions. Of 126 strains tested 20 satisfied screening criteria. 相似文献