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81.
Conidiobolus coronatus is an entomopathogenic fungus which has a potential as a biological control agent of insects. The cuticular and internal lipid composition of infected and noninfected Tettigonia viridissima males were analyzed by GC/MS. A total of 49 compounds were identified in the infected and noninfected males, including fatty acids, fatty acid methyl esters (FAMEs), n‐alkanes, alcohols, sterols, and other organic compounds. The most abundant components of the cuticular and internal lipids of the insects were fatty acids. After exposure to C. coronatus, the cuticular lipids of the T. viridissima males contained 17 free fatty acids from C(8) to C(22), while the cuticular lipids of the noninfected insects contained only 15 fatty acids from C(12) to C(24). The cuticular and internal lipids of both the infected and the noninfected males also contained five FAMEs from C(15) to C(19), seven n‐alkanes from C(25) to C(34), five alcohols from C(16) to C(25), five sterols, and the following six other organic compounds: azelaic acid, phenylacetic acid, glutaric acid, benzoic acid, sebacic acid, and glycerol. The compounds which were present only in the cuticular lipids of the infected males could be due to fungal infection.  相似文献   
82.
Truffles are prized and nutrition‐rich edible hypogeous fungi. The aim of this study was a comprehensive investigation of chemical composition of Burgundy truffle (Tuber aestivum Vittad .). We tried to answer the question: what is the impact of the environment on the truffle quality. To know the nutritional value of Burgundy truffle we compared lipids, proteins, saccharides, polyphenolics, flavonoids, total sterols, ergosterol, volatile flavour and aroma compounds content in fruit bodies of the fungus collected in three different geographical regions, i.e., Poland, Slovakia, and Italy. A comparison of the above mentioned compounds is especially interesting due to environmental and climatic differences among the studied geographical regions. Results revealed that fruit bodies of Taestivum from Poland and Slovakia possessed nearly similar content of proteins, total sterols, and saccharides. The fruiting bodies from Italy contained significantly larger amounts of most of the investigated compounds. In turn, Polish specimens had higher content of lipids and polyphenolics than Slovak and Italian ones. We have found higher similarity of volatile compounds composition between Polish and Italian specimens than those of Polish and Slovak origin.  相似文献   
83.
The conformation of a benzodiazepine-like decapeptide corresponding tothe YLGYLEQLLR fragment of a casein has been examined in a sodium dodecylsulfate micellar medium using circular dichroism, two-dimensional1H NMR spectroscopy and restrained molecular dynamicssimulation. The decapeptide adopts an amphipathic 310-helicoidstructure in which theE6···R10 ionic bridgestabilizes the C-terminus.  相似文献   
84.
A survey of distribution patterns of floodwater mosquito eggs related to environmental conditions such as moisture and plant associations was conducted by using soil samples from irrigated fields in Wroc?aw, Poland. Mosquito egg distribution was determined by repeatedly flooding the soil samples with aerated water at a temperature of 25° C. Under laboratory conditions, hatching in installments of Aedes caspius (Pallas) and Aedes vexans (Meigen) were commonly observed. The results show that ~75% of the larvae of Ae. caspius and Ae. vexans hatched after the first flooding under summer‐like conditions, whereas, following the second and third flooding, the numbers of hatched larvae were significantly lower. In our study, within one intermediate flooded field, a total of 66 plant species was identified and classified into six communities. All vegetation types were associated by varied egg densities and showed differences both in richness and Shannon‐Wiener diversity index as well as in ecological indices for moisture, soil reaction, and nutrient level. Small changes in elevation along the slope within the study area showed a large difference in the distribution of mosquito eggs. The highest average egg density was observed in zones with high occurrence of Phalaris arundinacea, usually prevalent in intermediate flooded and fertile areas. Knowledge of the indicators for the distribution of floodwater mosquito eggs in temporary breeding sites may be essential for organizing a successful, integrated mosquito control program with special regard to microbial control agents.  相似文献   
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doi: 10.1111/j.1741‐2358.2009.00303.x
Implant supported dentures: an estimation of chewing efficiency Background: Treatment of edentulous patients is one of the most demanding tasks the dentist can meet in his everyday practice. Implant based methods help to improve functioning of dentures and life quality of so treated patients. Objectives: The aim of the study was to evaluate the chewing efficiency of patients treated with lower complete implant‐supported overdentures and the simultaneous evaluation of treatment results by patients. Materials and methods: For the investigation were chosen edentulous patients, treated with upper conventional complete dentures and lower complete overdentures supported on two implants. In this group of patients, were conducted investigations of chewing efficiency changes, based on the Optocal test and overdentures functioning evaluation made by patients in the survey. Results: The objective evaluation of the chewing efficiency indicated the decrease of this value in the five years of observations. Lower complete overdentures supported on implants significantly increased the comfort of chewing of edentulous patients. Conclusions: The results of the study let us to assess positively the result of the therapy using titanium implants and lower complete overdentures. The therapy described significantly increases the life comfort of the edentulous patients. Decreasing chewing efficiency indicated by the research result should be compensated with the dentures maintaining or the prostheses exchange after about five years of use.  相似文献   
87.
The Second International Workshop on CMV & Immunosenescence was held in Cambridge, UK, 2-4th December, 2010. The presentations covered four separate sessions: cytomegalovirus and T cell phenotypes; T cell memory frequency, inflation and immunosenescence; cytomegalovirus in aging, mortality and disease states; and the immunobiology of cytomegalovirus-specific T cells and effects of the virus on vaccination. This commentary summarizes the major findings of these presentations and references subsequently published work from the presenter laboratory where appropriate and draws together major themes that were subsequently discussed along with new areas of interest that were highlighted by this discussion.  相似文献   
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The tagging‐via‐substrate approach designed for the capture of mammal prenylated proteins was adapted to Arabidopsis cell culture. In this way, proteins are in vivo tagged with an azide‐modified farnesyl moiety and captured thanks to biotin alkyne Click‐iT® chemistry with further streptavidin‐affinity chromatography. Mass spectrometry analyses identified four small GTPases and ASG2 (ALTERED SEED GERMINATION 2), a protein previously associated to the seed germination gene network. ASG2 is a conserved protein in plants and displays a unique feature that associates WD40 domains and tetratricopeptide repeats. Additionally, we show that ASG2 has a C‐terminal CaaX‐box that is farnesylated in vitro. Protoplast transfections using CaaX prenyltransferase mutants show that farnesylation provokes ASG2 nucleus exclusion. Moreover, ASG2 interacts with DDB1 (DAMAGE DNA BINDING protein 1), and the subcellular localization of this complex depends on ASG2 farnesylation status. Finally, germination and root elongation experiments reveal that asg2 and the farnesyltransferase mutant era1 (ENHANCED RESPONSE TO ABSCISIC ACID (ABA) 1) behave in similar manners when exposed to ABA or salt stress. To our knowledge, ASG2 is the first farnesylated DWD (DDB1 binding WD40) protein related to ABA response in Arabidopsis that may be linked to era1 phenotypes.  相似文献   
90.
In the past decade, various strategies to improve photosynthesis and crop yield, such as leaf morphology, light interception and use efficiency, biochemistry of light reactions, stomatal conductance, carboxylation efficiency, and source to sink regulation, have been discussed at length. Leaf morphology and physiology are tightly coupled to light capturing efficiency, gas exchange capacity, and temperature regulation. However, apart from the photoprotective mechanism of photosystem-II (PSII), i.e. non-photochemical quenching, very low genetic variation in the components of light reactions has been observed in plants. In the last decade, biochemistry-based enhancement of carboxylation efficiency that improves photosynthesis in plants was one of the potential strategies for improving plant biomass production. Enhancement of activation of the ubiquitous enzyme ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco; EC 4.1.1.39) by Rubisco activase may be another potential strategy for improving a photosynthesis-driven increase in crop yield. Rubisco activase modifies the conformation of the active center in Rubisco by removing tightly bound inhibitors, thereby contributing to enzyme activation and rapid carboxylation. Thermophilic cyanobacteria are oxygenic photosynthetic bacteria that thrive in high-temperature environments. This critical review discusses the prospects for and the potential of engineering Rubisco activase from thermophilic cyanobacteria into temperature-sensitive plants, to increase the threshold temperature and survival of these plants in arid regions.  相似文献   
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