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81.
82.
Vincristine and paclitaxel are widely used antitumoral drugs that interfere with microtubule dynamics. We have previously demonstrated that vincristine induces phosphorylation of HSP27 at serine 82 in MCF-7 cells. In this report, we show that vincristine also causes phosphorylation of serines 78 and 15. Moreover, we demonstrate that phosphorylation of this chaperone is induced by the p38 signalling pathway while the JNK pathway is not implicated. Differences between vincristine and paclitaxel treatments are also appreciated. Thus, while vincristine induces a strong phosphorylation of the three serines, paclitaxel induces a weak phosphorylation of serine 78 and has no effect over serines 82 and 15 phosphorylation. Interestingly, pre-treatment of cells with a ten-fold excess of paclitaxel abolishes vincristine-induced phosphorylation of HSP27.  相似文献   
83.
We report the characterization of a cDNA induced in mouse macrophages that encodes a 332-amino acid protein with extensive sequence identity with members of the mammalian nudC-like genes. The interaction between mNUDC and the regulatory beta subunit of platelet activating factor acetylhydrolase I (PAF-AH(I)) shown in this article indicates a new function of NUDC. Thus, we show that NUDC increases the catalytic activity of PAF-AH(I) and that this regulatory activity is located in the carboxyl terminal half of the protein which is highly conserved. This suggests a novel function for mammalian nudC-like genes as anti-inflammatory proteins.  相似文献   
84.
The dung incorporation activity of three species of coprophagous beetle macrofauna (Coleoptera: Scarabaeidae: Scarabaeinae), Dichotomius colonicus (Say), Phanaeus quadridens (Say), and Copris klugi sierrensis Matthews, was studied on a hectare of pastureland on "La Michilía" Biosphere Reserve. In total, 223 specimens of the three species were recorded. On the basis of abundance, the dominant species was D. colonicus. A substantial percentage (31% in September and 51% in October) of dung pats remained on the surface, untouched by beetles. Most of the specimens observed (92%) were found amassing dung in galleries. The dung accumulation capacity of D. colonicus varied from 5 to 135 g of dung (dry weight)/pair, whereas C. klugi sierrensis amassed an average of 24.3 +/- 8.5 g/pair and P. quadridens amassed an average of 12 +/- 2.5 g/pair. Based on dung burying efficiency, D. colonicus was considered the most beneficial of the three species in the study area. It dug deeper, wider galleries and incorporated the largest amount of dung into the soil.  相似文献   
85.
86.
The objectives of this study were to evaluate the microbial prevalence inside six repositories of the National Archive of the Republic of Cuba in 2?months of the year and to examine some of the physiological features of fungi isolated in order to evaluate their potential for biodeterioration. The microbiological sampling was conducted in February and September using a slit impactor as air sampler. Appropriate selective culture media were used to isolate fungi and bacteria. Temperature and relative humidity were measured during the samplings. The cellulolytic activity and the production of acids and pigments of the fungi isolated were qualitatively determined. Total viable microbiota and bacteria concentrations were greater in February while the fungal concentration was higher in September. Aspergillus, Cladosporium, Penicillium, Curvularia and Alternaria were the predominant fungal genera in February while Cladosporium prevailed in September, although Fusarium, Mucor and Neurospora genera were also isolated in this month. The fungi isolated were capable of degrading cellulose and excreting pigments and acids. The Gram-positive bacteria group prevailed in the air and Corynebacterium, Streptomyces, Bacillus, Streptococcus, Staphylococcus, Enterobacter and Serratia were some of the genera identified.  相似文献   
87.
An optimized protocol for the development and discovery of polymorphic AFLP markers in tree species is described. The protocol was optimized for the production of fluorescently labeled PCR products and analysis using a capillary sequencer. This approach has been demonstrated to be efficient and reproducible for tree species with complex genomes. The most important modification was in the selective amplification step. Instead of using a traditional step down PCR, a fixed and higher annealing temperature was employed, improving the reproducibility and sensitivity of the protocol. The levels of polymorphisms detected with the optimized protocol on three woody species are in agreement with those previously reported in the literature for tree species.  相似文献   
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89.
The use of acoustic signals by males during courtship and mating is well known. Nevertheless, their association with female unwillingness to mate is much less studied. In spiders, stridulation during sexual interactions is relatively common in some groups, but mainly restricted to males. In the pholcid spider Holocnemus pluchei, both sexes have stridulatory organs. The aims of the present work were (1) to establish whether female stridulation occurs during intra‐ and inter‐sexual interactions, (2) to determine whether female reproductive status affects the likelihood that she will stridulate and (3) to determine whether female stridulation is influenced by male sexual behaviour. We found that female stridulation usually occurs both during intrasexual interactions and, most frequently, during intersexual interactions. Females with more previous matings stridulated more frequently. Stridulation intensity was higher in females that did not accept new copulations compared with those that copulated. Female stridulation did not vary in elaborated and non‐elaborated courtship. Thus, females use stridulation to communicate levels of sexual receptivity. It is also possible that females use stridulation to indirectly assess male ability to persist and persuade.  相似文献   
90.
Using geolocator-immersion loggers, we tracked for the first time the migration of one Cory’s Shearwater Calonectris borealis fledgling, from its breeding colony in the Canary Islands, and along its first year of life. The juvenile bird initially followed the same migratory path as the adults but visited different areas of the Central and the South Atlantic Ocean.  相似文献   
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