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631.
Fire plays an important role in the evolution of life-history characteristics of organisms living in fire-prone regions. Although there are many reports of plants exhibiting adaptations to reduce the harmful or lethal effects of fire, little is known about fire-resistance mechanisms among animals, other than fleeing responses. Here, we report observations that may represent a type of fire adaptation in a bird species: bowers in one population of the Great Bowerbird Chlamydera nuchalis remained unburned after fire. If a bower is destroyed by fire or other mechanisms during courtship and breeding season, the male may lose the opportunity to mate with females, thereby reducing his apparent fitness. Therefore, traits that minimise the damage to bowers from fires may be beneficial. By measuring the unburned areas surrounding bowers after fires, we showed that the survival of bowers after fires is unlikely to be solely related to chance. Our observations are consistent with the hypothesis that bower resistance to fire is an adaptation of the Great Bowerbird. However, it is also possible that unburned bowers are by-products of sexual selection.  相似文献   
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1. A novel acid phosphatase isozyme E (formerly null mutant 0) was partially purified by ammonium sulfate fractionation, DEAE-Sephacel and Sephacryl S-200 column chromatography, and its properties were compared with those of other isozymes of the silkworm hemolymph. 2. The isozyme E was extremely heat labile and showed lower pH-stability than those of others. 3. Three isozymes hydrolyzed p-nitrophenyl phosphate, alpha-naphthyl phosphate, alpha-naphthyl phosphate and glucose-1-phosphate strongly. The isozyme E showed about 50% hydrolyzing activity for alpha-naphthyl phosphate as compared to those of A and B. 4. Activities of three isozymes were inhibited by tartaric acid, sodium fluoride, ammonium molybdate and potassium diphosphate. Inhibitory effects of Cu(2+) and HG(2+) were most remarkable against E isozyme.  相似文献   
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It is not widely known that incorrect use of oral bisphosphonates (BPs), such as chewing the medication, can cause oral ulcers. An 83‐year‐old woman with dementia was referred to our clinic with multiple oral ulcers. Blood and histopathological examinations were inconclusive. Further questioning revealed that the patient chewed the oral BP, resulting in oral ulceration. Patients with loss of cognitive function, such as dementia, are at risk of oral ulcers caused by incorrect use of BPs.  相似文献   
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Affinity labeling of yeast and B. stearothermophilus phosphoglycerate kinases with a reactive AMP analog, N6-(p-bromoacetaminobenzyl)-AMP was examined. Complete loss of enzyme activity was observed when 1 mol of the reagent had reacted per mol of either enzyme. Results on the effect of pH and substrate addition on the inactivation, titration of SH groups before and after modification, and kinetic studies with AMP analogs suggest that the modification occurs at one amino group at or near the substrate binding site. General affinity labeling of kinases is discussed based on the results obtained.  相似文献   
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Replication factor C (RFC) catalyzes the assembly of circular proliferating cell nuclear antigen (PCNA) clamps around primed DNA, enabling processive synthesis by DNA polymerase. The RFC-like genes, arranged in tandem in the Thermococcus kodakaraensis KOD1 genome, were cloned individually and co-expressed in Escherichia coli cells. T. kodakaraensis KOD1 RFC homologue (Tk-RFC) consists of the small subunit (Tk-RFCS: MW=37.2 kDa) and the large subunit (Tk-RFCL: MW=57.2 kDa). The DNA elongation rate of the family B DNA polymerase from T. kodakaraensis KOD1 (KOD DNA polymerase), which has the highest elongation rate in all thermostable DNA polymerases, was increased about 1.7 times, when T. kodakaraensis KOD1 PCNA (Tk-PCNA) and the Tk-RFC at the equal molar ratio of KOD DNA polymerase were reacted with primed DNA.  相似文献   
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