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111.
A methodology is proposed for assessing the ecological value of streams in the catchment of the Moravská Dyje River. It is concluded that by using a wide range of parameters that a more objective assessment is achieved than if only one were used. The landscape of the catchment studied contains excessive amounts of nutrients and, in comparison to its natural state, has become too uniform. 相似文献
112.
E. Rabino Massa R. Melleri L. Tagliaro G. Boëtsch 《International Journal of Anthropology》1996,11(2-4):83-90
Until World War II the economic activity of the inhabitants of the commune of Fontanigorda (Genova — Italy) was based on subsistence
farming and temporary migration. Migration to France in search of work absorbed the excess active male population: the isonymy
study shows that the migrants were recruited from all the families of the commune.
After having left for Marseilles or the mine at St. Maime (in the Alps of Upper Provence), these young migrants returned to
their home town to marry.
This behaviour maintained a high degree of consanguinity, obscured by a false exogamy, at least until the turn of the century.
After this period, lifelong migration completely modified the pattern of marriage structure bacause migration to France became
definitive. 相似文献
113.
C. Sauvain-Dugerdil G. Boëtsch C. Serrano-Sanchez 《International Journal of Anthropology》1996,11(2-4):3-11
this first paper introduces the topic of the volume, outcomes of a symposium organised at the 13th ICAES held in Mexico in
August 1993. It briefly reminds of the convergence between anthropology and demography up to date and stresses on the need
of real transdisciplinary work in this challenging domain. The aim of the symposium was to make a contribution on the central
theme chosen by the congress — the cultural and biological dimensions of global change — while examining the place of demographic
anthropology in the study of change. The papers presented at the symposium have been organised in three parts which form the
present volume: the composition of population, the choice of spouse and mobility, the reproduction and dynamics of populations.
The basic mechanisms of change are considered through examples at the level of local populations. This also leads to question
the definitions of human groups and to make a “declaration” stressing on the importance of individual heterogeneity and the
arbitrariness and reductive nature of any grouping of individuals, stating therefore the misapprehension of the most recent
scientific work inherent to the rationale of programs of “ethnic cleasing”.
Translated from the french by prof. Derek F. Roberts 相似文献
114.
Living yeast cells can be selectively stained with the lipophilic cationic cyanine dye DiOC6(3) in a mitochondrial membrane potential-dependent manner. Our study extends the use of flow cytometric analysis and sorting to DiOC6(3)-stained yeast cells. Experimental conditions were developed that prevented the toxic side effect of the probe and gave a quantitative correlation between fluorescence and mitochondrial membrane potential, without any staining of other membranes. The localization of the fluorochrome was checked by confocal microscopy and image cytometry. The mitochondrial membrane alterations were also tested through cardiolipin staining with nonyl acridine orange. Differences in light scattering and in fluorescence were detected in mutants (rho-, rho degrees, mit-, or pet-) and wild-type (rho+mit+) populations of yeast. The dye uptake of respiratory-deficient yeast strains was significantly reduced as compared to that of the wild-type. Application of an uncoupler (mCICCP), which collapsed the mitochondrial membrane potential (alphapsi(m)), led to a drastic reduction of the dye uptake. It was observed that a decrease in deltapsi(m), was usually correlated with a decrease in cardiolipin stainability by nonyl acridine orange (NAO). Quantitative flow cytometry is a fast and reproducible technique for rapid screening of yeast strains that might be suspected of respiratory dysfunction and/or mitochondrial structural changes. We give evidence that it is an adequate method to characterize and isolate respiratory mutants through sorting procedure, with selective enrichment of the population studied in respiring or non-respiring yeast cells. Confocal microscopy and image cytometry corroborate the flow cytometry results. 相似文献
115.
Ernest V. Curto Ted T. Sakai Michael J. Jablonsky Sandrine Rio-Anneheim Jean-Claude Jacquinet N. Rama Krishna 《Glycoconjugate journal》1996,13(4):599-607
We present complete1H NMR assignments for two synthetic glycopeptides representative of the carbohydrateprotein linkage region of serglycin proteoglycans. The peptides are: Ser(Galp-Xylp)-Gly-Ser-Gly-Ser(Galp-Xylp)-Gly and, Ser(Galp-Xylp)-Gly-Ser(Galp-Xylp)-Gly-Ser(Galp-Xylp)-Gly. A number of 2D NMR spectra together with a 3D NOESY-TOCSY spectrum were acquired at 600 MHz to complete the assignments of the glycopeptides dissolved in water with 40% trifluoroethanol. Preliminary analysis of the NMR data suggests folded structures for the glycopeptides.A preliminary account of this work was presented at an International Symposium held at the University of Alabama at Birmingham in November, 1994 on the occasion of the 65th birthday of Professor Lennart Rodén. 相似文献
116.
Benoît F. Morel Meghan A. Burke Jayant Kalagnanam Susan A. McCarthy David J. Tweardy Penelope A. Morel 《Bulletin of mathematical biology》1996,58(3):569-594
The cytokines are the information superhighway of the immune system. They are an important component of the integrated behavior
of the system. In order to be able to have a good understanding of the immune system, we must be able to model the effect
of cytokines and their combined effect. This work is a step in that direction. We study the combined effect of two cytokines:
interleukin-2 (IL-2) and interleukin-4 (IL-4) on some cells of the immune system.
Interleukin-2 and interleukin-4 are important growth and differentiation factors for B and T cells. Interleukin-4 antagonizes
the effect of interleukin-2 on B cells and some T cells while it synergizes with interleukin-2 on other T cells. We build
a mathematical model of the interaction of both cytokines on T and B cells as a building block toward a model of the Th1/Th2
cross-regulation. The response of a given cell to the combination of interleukin-2 and interleukin-4 is shown to involve competing
dynamical effects which can lead to either antagnostic or synergistic combined effect.
Author to whom correspondence should be addressed at Department of Engineering and Public Policy. Work supported by NIH grant
nv: Ai31427. 相似文献
117.
A new gene coding for an antigen recognized by autologous cytolytic T lymphocytes on a human renal carcinoma 总被引:7,自引:0,他引:7
Béatrice Gaugler Nathalie Brouwenstijn Valérie Vantomme Jean-Pierre Szikora Corry W. Van der Spek Jean-Jacques Patard Thierry Boon Peter Schrier Benoît J. Van den Eynde 《Immunogenetics》1996,44(5):323-330
Previous reports have described antigens that are recognized on human melanoma cells by autologous cytolytic T lymphocytes
(CTL). The genes coding for a number of these antigens have been identified. Here we report the cloning of a gene that codes
for an antigen recognized by autologous CTL on a human renal carcinoma cell line. This antigen is presented byHLA-B7 and is encoded by a new gene that we have namedRAGE1. No expression ofRAGE1 was found in normal tissues other than retina. RAGE1 expression was found in only one of 57 renal cell carcinoma samples,
and also in some sarcomas, infiltrating bladder carcinomas, and melanomas. This represents the first identification of an
antigen recognized by autologous CTL on a renal tumor. 相似文献
118.
On Normandy coasts, the red alga Delesseria sanguinea perennates by its stipe; fronds grow in January and disappear in June. Seasonal variations in sterol composition in relation to the biology of D. sanguinea are reported. Sterols in cellular membranes are free or conjugated by esterification with fatty acids, heterosides or lipid complexes like phospholipids. Both kinds of sterols were analyzed by GC-MS. The major sterol (80%) found in fronds was cholesterol whereas in stipes, cholesterol was also the major sterol in spring, but in September, an important reduction in cholesterol yield was noted with proportional increase in sitosterol content. It appears that cholesterol is synthesized in fronds in spring, then transferred to the stipe, which loses an important amount of cholesterol with loss of the blades. 相似文献
119.
Vascular endothelial cells: Targets for studying the activity of hair follicle cell-produced VEGF 总被引:1,自引:0,他引:1
S. Lachgar M. Charvéron Y. Gall J. Plouët J. L. Bonafé 《Cell biology and toxicology》1996,12(4-6):331-334
Fetal bovine aortic endothelial cells (FBAEC) were exposed to purified fractions of conditioned medium from cultures of hair dermal papilla cells (DPC) to determine the existence of any vascular endothelial growth factor (VEGF)-like paracrine activity of the latter. Such fractions were tested for stimulation of growth and migration of cultured FBAEC. In addition, VEGF secretion by DPC was measured by radioassay of VEGF receptors using FBAEC as target cells. The results showed that stimulation of FBAEC proliferation and migration following exposure to purified conditioned medium was dose-dependent. Radioreceptor assays of recombinant VEGF and purified DPC-conditioned medium showed competitive VEGF binding in FBAEC.Abbreviations CM
conditioned medium
- DMEM
Dulbecco's modified eagle's medium
- DPC
dermal papilla cells
- EDTA
ethylenediaminetetra-acetic acid
- FBAEC
fetal bovine aortic endothelial cells
- FCS
fetal calf serum
- VEGF
vascular endothelial growth factor 相似文献
120.
Hong Luo Benoît Van Coppenolle Marc Seguin Marc Boutry 《Molecular breeding : new strategies in plant improvement》1995,1(1):51-63
Using fourteen random mitochondrial DNA probes, we have examined restriction fragment length polymorphism (RFLP) in wild and cultivatedHevea brasiliensis. A total of 395 accessions, including 345 from various prospectings collected in Brazil, Colombia and Peru and 50 cultivated clones, were analyzed. Two other species (H. benthamiana andH. pauciflora) were also included in the study for comparison. The high level of mitochondrial polymorphism allowed us to divide all the accessions analyzed into 212 distinct genotypes. The genetic variability of cultivated clones was limited to four genotypes forming two clusters. In contrast, considerable genetic variation was found in the wild collections. In almost all cases, accessions displaying the same RFLP profile were restricted to the same geographical area (same or neighbor administrative districts). In addition, accessions whose genetic closeness was predicted by RFLP profiles were also clustered according to geographical origin. In a few cases, however, similar RFLP profiles were found for accessions originating from geographically distant districts. This discrepancy can be explained either by seed dispersion (by river) or possibly by similar genetic events occurring independently in different geographical locations. Chloroplast DNA RFLP was also analyzed in 217 accessions, representative of 126 distinct mitochondrial genotypes. Very few differences were found, indicating that the chloroplast genome is more highly conserved than the mitochondrial genome. 相似文献