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981.
982.
Binding studies using (125)I-Cry1Ac and biotinylated Cry1Fa toxins indicate the occurrence of a common receptor for Cry1Ac, Cry1Fa, and Cry1Ja in Helicoverpa armigera, Helicoverpa zea, and Spodoptera exigua. Our results, along with previous binding data and the observed cases of cross-resistance, suggest that this pattern seems to be widespread among lepidopteran species. 相似文献
983.
Pablo?González-Melendi María?Antonietta?Germanà Nathalie?Levy?Guarda Benedetta?Chiancone María?Carmen?Risue?oEmail author 《Acta Physiologiae Plantarum》2005,27(4):687-694
Before approaching anther culture as a tool to trigger an androgenic response in a new species, it is advisable to characterize
and correlate flower and male gametophyte development to enable reproducible identification of the appropriate starting material.
Buds and flowers of Opuntia ficus-indica cv. Gialla were classified in eight stages according to their total length at the earlier stages and the length of the corolla
in flowers with emerging sepals. Due to the low condensation of chromatin in the microspore nucleus as well as in the vegetative
nucleus of the bi- and tricellular pollen along with the high autofluorescence of the intricate exine, DAPI staining turned
out not to be feasible in this species. Therefore an approach based on light-microscopy observation of semithin sections was
used. These sections were stained with toluidine blue for general structure recognition and I2KI to study starch deposition. Correlations were made between the sequential floral and male gametophyte development. Using
this approach we determined the timing of pollen formation and observed that pollen development is impaired in plants producing
seedless fruits. Furthermore, anther culture was carried out with anthers collected from flower buds at stages 2 and 3. Most
of the anthers produced callus, however no regeneration was obtained. 相似文献
984.
Koury JC de Oliveira CF Portella ES Oliveira AV Donangelo CM 《Biological trace element research》2005,107(3):201-211
The purpose of this study was to evaluate the effect of the resting period on hematological and copper-zinc-dependent antioxidant
indices in Brazilian elite judo athletes (n=7). Venous blood samples were collected after 24-h and 5-d periods of resting following a competition, with an interval of
30 d between collections. Two months prior to and during the study, each athlete received an individualized adequate diet.
Body composition was determined at both study periods. The following were analyzed: in whole blood, hemoglobin, hematocrit,
red cell count, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, red cell
distribution width, and white cell count; in plasma, zinc, copper, iron, ceruloplasmin, and total iron-binding capacity; in
erythrocytes, metallothionein, copper/zinc superoxide dismutase, and osmotic fragility. Dietary intake and body composition
did not affect the biochemical measurements. A significant reduction in ceruloplasmin and superoxide dismutase activity was
found after 5 d compared to 24 h of resting. A significant correlation between erythrocyte metallothionein and red cell distribution
width was observed after 24 h of resting (r=−0.83, p=0.02) whereas positive correlations of metallothionein with hemoglobin, red cell count, and mean corpuscular hemoglobin concentration
were observed after 5 d of resting (r≥0.76, p≤0.05). Our results suggest that a longer resting period favors homeostatic adjustments in the erythrocyte population and
in the copper/zinc-dependent antioxidant system in elite judo athletes. 相似文献
985.
986.
987.
Barber DF Bartolomé A Hernandez C Flores JM Redondo C Fernandez-Arias C Camps M Rückle T Schwarz MK Rodríguez S Martinez-A C Balomenos D Rommel C Carrera AC 《Nature medicine》2005,11(9):933-935
Systemic lupus erythematosus (SLE) is a chronic inflammatory disease generated by deregulation of T cell-mediated B-cell activation, which results in glomerulonephritis and renal failure. Disease is treated with immunosuppressants and cytostatic agents that have numerous side effects. Here we examine the use of inhibitors of phosphoinositide 3-kinase (PI3K) gamma, a lipid kinase that regulates inflammation, in the MRL-lpr mouse model of SLE. Treatment reduced glomerulonephritis and prolonged lifespan, suggesting that P13Kgamma may be a useful target in the treatment of chronic inflammation. 相似文献
988.
SUMMARY: ProfDist is a user-friendly software package using the profile-neighbor-joining method (PNJ) in inferring phylogenies based on profile distances on DNA or RNA sequences. It is a tool for reconstructing and visualizing large phylogenetic trees providing new and standard features with a special focus on time efficency, robustness and accuracy. AVAILABILITY: A Windows version of ProfDist comes with a graphical user interface and is freely available at http://profdist.bioapps.biozentrum.uni-wuerzburg.de 相似文献
989.
990.
Lucrecia?Arellano Mario?E.?FavilaEmail author Carmen?Huerta 《Biodiversity and Conservation》2005,14(3):601-615
This paper analyzes the diversity of dung and carrion beetles (Scarabaeinae and Silphidae) in four human-induced habitats of a disturbed tropical montane cloud forest: polyspecific shade coffee plantations, monospecific shade coffee plantations, tropical montane cloud forest fragments, and clear cuts. The four habitats had similar richness, species composition, and assemblage structure of dung and carrion beetles. Differences were found in abundance and biomass levels for the four dominant species in the landscape. Dung beetles were more abundant than carrion beetles, but the biomass was higher for the latter. Carrion beetles were seasonal, while dung beetles were clearly not. When forest fragments and shade coffee plantations were compared to other similar habitats in the region, the same general pattern was observed. However, forests with high disturbance and monospecific shade coffee plantations had lower species richness than forests with low and medium disturbance and polyspecific shade coffee plantations. Thus shade coffee plantations maintain connectivity between patches of cloud forest in a landscape that is strongly affected by human activities. Protecting landscape diversity appears to ensure high species richness. 相似文献