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151.
Ferruh Aşçi 《Biologia》2009,64(6):1146-1149
In this study, the structural characteristics, unique features, various organ measurements of males and females of the water mite Atractides (Atractides) turcicus sp. n. from Turkey are described. In addition, the study compares their characteristics with related species.  相似文献   
152.
Current patterns of floral design in Pedicularis must have undergone an evolutionary process of interacting among components of floral traits, and then formed internal relationships among these traits. To detect such correlations, which may provide insight to understand flower evolution, 40 Pedicularis species representing all corolla types of the genus were studied. Results show that, interspecifically, pollen size correlates negatively with pollen number, but positively with pistil length. This suggests that plants evolve an optimal pollen size, which balances the advantages of large pollen size for gametophytic competition against the fecundity disadvantages of fewer pollen grains. In contrast to sex allocation theory, this study does not find a trade-off, but an interspecific positive correlation between pollen and ovule number. This is consistent with the hypothesis that genetic variation for resource acquisition may in part be responsible for the lack of negative correlation between male and female function.This work was supported by the State Key Basic Research and Development Plan, China (Grant No. G2000046804) to YHG. The authors would like to thank Peter K. Endress and two anonymous reviewers for providing critical comments and helpful suggestions, Qing-Feng Wang, Jing-Yuan Wang and Jin-Ming Chen for their helpful suggestions. Shi-Guo Sun, Jing Xia, and Qian Yu are thanked for their assistance in both the field work and laboratory phases of the project.  相似文献   
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154.
Connective tissue growth factor (CTGF/CCN2) is overexpressed in diabetes. Diabetic rats possess myocardial and cardiomyocyte hypertrophy. In a recent report, Wang and colleagues (Am J Physiol Cell Physiol. 2009 Jul 22. [Epub ahead of print]) show that CCN2 directly mediates cardiomyocyte hypertrophy as well as that induced by high glucose and fatty acid. CCN2 acted via the TrkA receptor. These data are the subject of this commentary, and emphasize that CCN2 may be an excellent target for therapy in diabetes.  相似文献   
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156.
This work investigates the impact of structural parameters on the rheological behaviour of apple purees. Reconstructed apple purees from 0 g/100 g up to 2.32 g/100 g of insoluble solids content and varying in particle size were prepared. Three different particle size distributions were obtained by mechanical treatment only, to modify both size and morphology of the particles without modifying the intrinsic rigidity of the cell walls. Rheological measurements showed that the insoluble solids content have a first order effect on the rheological behaviour of the suspensions: three concentrations domains were observed in both dynamic and flow measurements. A model is proposed for each domain. The existence of a weak network between particles is clearly shown over a critical concentration of insoluble solids (cell walls) depending on particle size distribution (semi-diluted domain). In a concentrated domain, particles are on close packing conditions and their apparent volume begin to shrink. Particle size and shape also play an important role on the rheological behaviour of reconstructed apple puree. Due to their irregular shape, cell clusters clog the medium at lower concentration compared to individual cells.  相似文献   
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158.
Bone and tooth, fundamental parts of the craniofacial skeleton, are anatomically and developmentally interconnected structures. Notably, pathological processes in these tissues underwent together and progressed in multilevels. Extracellular vesicles (EVs) are cell-released small organelles and transfer proteins and genetic information into cells and tissues. Although EVs have been identified in bone and tooth, particularly EVs have been identified in the bone formation and resorption, the concrete roles of EVs in bone and tooth development and diseases remain elusive. As such, we review the recent progress of EVs in bone and tooth to highlight the novel findings of EVs in cellular communication, tissue homeostasis, and interventions. This will enhance our comprehension on the skeletal biology and shed new light on the modulation of skeletal disorders and the potential of genetic treatment.  相似文献   
159.
The cause of the pregnancy condition preeclampsia (PE) is thought to be endothelial dysfunction caused by oxidative stress. As abnormal glucose tolerance has also been associated with PE, we use a fluorinated-mimic of this metabolite to establish whether any oxidative damage to lipids and proteins in the erythrocyte membrane has increased cell membrane permeability. Data were acquired using 19F Dynamic-NMR (DNMR) to measure exchange of 3-fluoro-3-deoxyglucose (3-FDG) across the membrane of erythrocytes from 10 pregnant women (5 healthy control women, and 5 from women suffering from PE). Magnetisation transfer was measured using the 1D selective inversion and 2D EXSY pulse sequences, over a range of time delays. Integrated intensities from these experiments were used in matrix diagonalisation to estimate the values of the rate constants of exchange and membrane permeability. No significant differences were observed for the rate of exchange of 3-FDG and membrane permeability between healthy pregnant women and those suffering from PE, leading us to conclude that no oxidative damage had occurred at this carrier-protein site in the membrane.  相似文献   
160.
A general in vitro cloning system was established for four Helleborus species: H. argutifolius, H. foetidus, H. niger and H. orientalis. The plant material was introduced in vitro from axillary buds. A Murashige and Skoog (MS)—based medium (Murashige and Skoog 1962) was used supplemented with 2% (w/v) sucrose, 2-isopentenyladenine (2-iP) and 6-benzylaminopurine (BA). Multiplication rates depended on the genotype and varied from 1.3 for H. foetidus till 3.8 for H. niger. The first results showed that the rooting phase could be done ex vitro. Rooting was induced by a drench for one week in a solution of indole-3-butyric acid (IBA -3 mg l−1) and 1-naphthaleneacetic acid (NAA-1 mg l−1) at 5°C.  相似文献   
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