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991.
992.
Human granulocyte colony-stimulating factor (G-CSF), and a mutant having a Ser for Cys substitution at residue 18 were produced in Escherichia coli strain W3110. About 60 mg of pure protein was obtained from 50 g of wet cells with a recovery of about 20%. The proteins were characterized physically and chemically, including determination of disulphide bonds, which were found to exist between residues 37-43 and 65-75. Cys-18 is not involved in disulphide bond formation and was substituted by Ser with no effects on gross protein conformation or biological activity. Both the wild-type and the mutant recombinant-derived proteins, although not glycosylated, possess colony-stimulating activities. In a bioassay using the murine myelomonocytic leukaemic cell line WEH1 3B D+, activities were obtained which were similar to those of natural G-CSF and of a glycosylated recombinant-derived human G-CSF produced in monkey cells.  相似文献   
993.
994.
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995.
The occurrence of mycotic agents was investigated by hair-brush technique on the coat of 162 naturalized coypus (Myocastor coypus) and 64 indigenous brown rats (Rattus norvegicus) originating from the same protected area in Central Italy. The isolates from positive coypus (29.6%) were identified as Microsporum gypseum (14.8%), Trichophyton terrestre (9.8%), Alternaria sp. (3.7%), Trichophyton mentagrophytes (2.5%), Cladosporium sp. (1.8%), Scopulariopsis sp. (1.2%), and Chrysosporium keratinophilum (0.6%), whereas the isolates from positive rats (46.7%) were identified as M. gypseum (28.1%), T. mentagrophytes (12.5%), Chrysosporium tropicum and T. terrestre (3.1% each), and Chrysosporium inops (1.6%). Statistically, brown rats were more likely to harbor fungal agents (P < 0.05) on their coat than coypus, especially T. mentagrophytes (P < 0.01) and M. gypseum (P < 0.05). No positive animal showed dermatological lesions. The present results are the first providing basic information on the coat’s mycoflora of a wild coypu population. It is concluded that the coypu, an allochthonous rodent in Italy, can play a role as natural animal reservoir of dermatophytes and as carrier of keratinophilic and saprophytic fungi within its new habitat, though to a lesser extent than indigenous rats. Therefore, people who are exposed to the risk of contact with the coat of rats and coypus should take all the cautions needed to protect themselves from mycotic agents potentially transmissible to humans.  相似文献   
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997.
cDNA arrays were used to explore mechanisms controlling fruiting body development in the truffle Tuber borchii. Differences in gene expression were higher between reproductive and vegetative stage than between two stages of fruiting body maturation. We suggest hypotheses about the importance of various physiological processes during the development of fruiting bodies.  相似文献   
998.
This work demonstrates a contribution of ethylene and NO (nitric oxide) in MP (mastoparan)‐induced cell death in the green algae Chlamydomonas reinhardtii. Following MP treatment, C. reinhardtii showed massive cell death, expressing morphological features of PCD (programmed cell death). A pharmacological approach involving combined treatments with MP and ethylene‐ and NO‐interacting compounds indicated the requirement of trace amounts of both ethylene and NO in MP‐induced cell death. By employing a carbon dioxide laser‐based photoacoustic detector to measure ethylene and a QCL (quantum cascade laser)‐based spectrometer for NO detection, simultaneous increases in the production of both ethylene and NO were observed following MP application. Our results show a tight regulation of the levels of both signalling molecules in which ethylene stimulates NO production and NO stimulates ethylene production. This suggests that, in conjunction with the elicitor, NO and ethylene cooperate and act synchronously in the mediation of MP‐induced PCD in C. reinhardtii. To the best of our knowledge, this is the first report on the functional significance of ethylene and NO in MP‐induced cell death.  相似文献   
999.
Molecular Biology Reports - The enhancement of fish immune system and growth performance throughout the administration of bio-friendly agents such as diet supplements (taurine) is considered a...  相似文献   
1000.
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