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991.
Alginate‐gelatin encapsulation of human endothelial cells promoted angiogenesis in in vivo and in vitro milieu
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992.
993.
Claude Barberis Neil Moorcroft James Pribish Elina Tserlin Alexandre Gross Mark Czekaj Matthieu Barrague Paul Erdman Tahir Majid Joseph Batchelor Mikhail Levit Andrew Hebert Liduo Shen Sandra Moreno-Mazza Anlai Wang 《Bioorganic & medicinal chemistry letters》2017,27(20):4735-4740
N-Substituted azaindoles have been discovered as pan-PIM kinase inhibitors. Initial SAR, early ADME and PK/PD data of a series of compounds is described and led to the identification of promising pan-PIM inhibitors which validated our interest in the 7-azaindole scaffold and led us to pursue the identification of a clinical candidate. 相似文献
994.
Tournament ABC analysis of the western Palaearctic population history of an oak gall wasp,Synergus umbraculus
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Graham N. Stone Sarah C. White György Csóka George Melika Serap Mutun Zsolt Pénzes S. Ebrahim Sadeghi Karsten Schönrogge Majid Tavakoli James A. Nicholls 《Molecular ecology》2017,26(23):6685-6703
Approximate Bayesian computation (ABC) is a powerful and widely used approach in inference of population history. However, the computational effort required to discriminate among alternative historical scenarios often limits the set that is compared to those considered more likely a priori. While often justifiable, this approach will fail to consider unexpected but well‐supported population histories. We used a hierarchical tournament approach, in which subsets of scenarios are compared in a first round of ABC analyses and the winners are compared in a second analysis, to reconstruct the population history of an oak gall wasp, Synergus umbraculus (Hymenoptera, Cynipidae) across the Western Palaearctic. We used 4,233 bp of sequence data across seven loci to explore the relationships between four putative Pleistocene refuge populations in Iberia, Italy, the Balkans and Western Asia. We compared support for 148 alternative scenarios in eight pools, each pool comprising all possible rearrangements of four populations over a given topology of relationships, with or without founding of one population by admixture and with or without an unsampled “ghost” population. We found very little support for the directional “out of the east” scenario previously inferred for other gall wasp community members. Instead, the best‐supported models identified Iberia as the first‐regional population to diverge from the others in the late Pleistocene, followed by divergence between the Balkans and Western Asia, and founding of the Italian population through late Pleistocene admixture from Iberia and the Balkans. We compare these results with what is known for other members of the oak gall community, and consider the strengths and weaknesses of using a tournament approach to explore phylogeographic model space. 相似文献
995.
Mohammadreza Pourghayoumi Majid Rahemi Davood Bakhshi Ali Aalami Ali Akbar Kamgar-Haghighi 《Physiology and Molecular Biology of Plants》2017,23(2):321-330
The biochemical and molecular responses of five commercially well-known pomegranate cultivars to severe water stress were studied. The cultivars were subjected to 14-day water stress by withholding irrigation, followed by re-watering for 7 days. Results showed clear differences in metabolites contents and activities of antioxidant enzymes among various pomegranate cultivars during severe water stress and recovery. According to our results, increased accumulation of proline in pomegranate was not related to osmotic adjustment during severe water stress. Except for ‘Ghojagh’, leaves grown under severe water stress conditions showed symptoms of oxidative stress such as reduced chlorophyll concentration. The improved performance of ‘Ghojagh’ under drought stress may be associated with an efficient osmotic adjustment. The up- or down regulated expression of cytosolic glutathione reductase (cytosolic GR) and glutathione peroxidase were observed under drought conditions. Moreover, the suppressed expression of cytosolic GR was also noted. Comparatively, ‘Rabab’ exhibited higher antioxidant capacity and an efficient ROS-scavenging mechanism under drought stress. Lower levels of membrane lipid peroxidation in ‘Ghojagh’ and ‘Rabab’ under drought stress and the marked reduction of malondialdehyde concentration after re-watering represents that these cultivars have a good tolerance to drought stress. As a first step towards the study of the biochemical and molecular responses of pomegranate plants to water stress, this research provides new information into the mechanisms of drought tolerance in the plants. 相似文献
996.
Effect of Photogenerated Dipoles in the Hole Transport Layer on Photovoltaic Performance of Organic–Inorganic Perovskite Solar Cells
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Judicious choice of transport layer in organic–inorganic halide perovskite solar cells can be one of the essential parameters in photovoltaic design and fabrication techniques. This article reports the effect of optically generated dipoles in transport layer on the photovoltaic actions in active layer in perovskite solar cells with the architecture of indium tin oxide (ITO)/TiO x /CH3NH3PbI3–x Cl x /hole transport layer (HTL)/Au. Here, PTB7‐thieno[3,4‐b]thiophene‐alt‐benzodithiophene and P3HT‐poly(3‐hexylthiophene) are separately used as the HTL with significant and negligible photoinduced dipoles, respectively. Electric field‐induced photoluminescence quenching provides the first‐hand evidence to indicate that the photoinduced dipoles are partially aligned in the amorphous PTB7 layer under the influence of device built‐in field. By monitoring the recombination process through magneto‐photocurrent measurements under device operation condition, it is shown that the photoinduced dipoles in PTB7 layer can decrease the recombination of photogenerated carriers in the active layer in perovskite solar cells. Furthermore, the capacitance measurements suggest that the photoinduced dipoles in PTB7 can decrease charge accumulation at the electrode interface. Therefore, the studies indicate the important role of photoinduced dipoles in the HTL on charge recombination dynamics and provide a fundamental insight on how the polarization in transport layer can influence the device performance in perovskite solar cells. 相似文献
997.
The effect of water stress on the activities of key regulatory enzymes of the sucrose to starch pathway in wheat 总被引:23,自引:0,他引:23
Developmental changes in the starch and sucrose content of grains andthe activities of enzymes of starch synthesis in wheat were studied under waterstress conditions. Water stress caused a marked reduction in the sucrose andstarch content of the grains. Sucrose synthase (SS) and UDP-glucosepyrophosphorylase (UDP-Gppase), showed higher catalytic activity and moreresistance to water stress compared with amyloplastic enzymes. ADP-glucosepyrophosphorylase (ADP-Gppase) activity was reduced to a low level under bothin situ and osmotic stress conditions in which grainsfailed to accumulate dry matter in vivo. Granule-boundstarch synthase (GBSS) also responded rapidly to in situwater stress treatments as did ADP-Gppase. Reduction in GBSS activity at thetime of growth cessation in situ was less than that ofADP-Gppase and the enzyme did not respond to severe osmotic stress. Solublestarch synthase (SSS) was the enzyme most sensitive to water stress in that itresponded earlier, and to a greater extent, than the other enzymes. However,under severe dehydration conditions, leading to cessation of growth, thedeclinein SSS activity was less than that for ADP-Gppase. SSS showed the lowestin vitro activity followed by GBSS. These results suggestthat SSS is the site of response to water stress by which the rate of graingrowth can be affected, whereas growth cessation is due mainly to theinactivation of ADP-Gppase. 相似文献
998.
Majid Majlesi Seyed Shahram Shekarforoush Hamid Reza Ghaisari Saeid Nazifi Javad Sajedianfard Mohammad Hadi Eskandari 《Probiotics and antimicrobial proteins》2017,9(3):300-309
The objective of this study was to evaluate the efficiency of probiotics (Lactobacillus plantarum and Bacillus coagulans) against mercury-induced toxicity using a rat model. Mercury (Hg) is a widespread heavy metal and was shown to be associated with various diseases. Forty-eight adult male Wistar rats were randomly divided into six groups (control, mercury-only, each probiotic-only, and mercury plus each probiotic group). Hg-treated groups received 10 ppm mercuric chloride, and probiotic groups were administrated 1 × 109 CFU of probiotics daily for 48 days. Levels of mercury were determined using cold vapor technique, and some biochemical factors (list like glutathione peroxidase (GPx), superoxide dismutase (SOD), creatinine, urea, bilirubin, alanine transaminase (ALT), and aspartate transaminase (AST)) were measured to evaluate changes in oxidative stress. Oral administration of either probiotic was found to provide significant protection against mercury toxicity by decreasing the mercury level in the liver and kidney and preventing alterations in the levels of GPx and SOD. Probiotic treatment generated marked reduction in the levels of creatinine, urea, bilirubin, ALT, and AST indicating the positive influence of the probiotics on the adverse effects of Hg in the body. 相似文献
999.
High resolution lectin-gold cytochemistry was used to quantitatively analyze the distribution of glycoconjugates in the hamster
oviductal ampulla during the five stages of the estrous cycle. Lectins binding to N-acetyl-d-galactosamine-, d-galactose-, and sialic acid-associated glycoconjugates in the secretory granules of ampullary epithelial secretory cells
showed staining of equal intensity throughout the five different stages of the estrous cycle. In contrast, the labeling intensity
of glycoconjugates which contain N-acetylglucosamine as terminal sugar residues reached its maximum around the time of ovulation, i.e., at proestrus. Glycoconjugates
which carry fucose and mannose as terminal sugar residues appeared to be totally absent from the secretory granules of the
oviductal ampulla during the estrous cycle. Together, electron microscopic observations combined with quantitative results
indicate that N-acetyl-d-galactosamine-, d-galactose-, and sialic acid-associated glycoconjugates may be secreted into the ampullary lumen irrespective of the stage
of the estrous cycle, whereas the secretion of certain N-acetylglucosamine-associated glycoconjugates is stage specific and reaches its peak at the time of ovulation. These findings
suggest that, at the time of ovulation, the ampullary epithelium changes its secretory activity and contributes its secretory
products to the zona pellucida of oocytes freshly released from the ovary.
Accepted: 10 August 1998 相似文献
1000.
We used site-specific mutagenesis by targeting E179 and F190 on the structure of photoprotein Mnemiopsin 2 (Mn2) from Mnemiopsis leidyi. The tertiary structure of E179S and F190L mutants was made by the MODELLER program. Far-ultraviolet circular dichroism data showed that the overall secondary structural content of photoprotein is not changed upon mutation, however the helicity and stabilizing interactions in helical structure decreases in mutants as compared with the wild-type (WT) photoprotein. Fluorescence spectra data revealed that the tertiary structure of the mutants is more compact than that of WT Mn2. According to the heat-induced denaturation experiments data, the melting temperature (Tm) for the unfolding of tertiary structure of the F190L variant increases by 3°C compared with that of the WT and E179S mutant. Interestingly, the conformational enthalpy of the F190L mutant (86 kcal mol−1) is considerably lower than those in the WT photoprotein (102 kcal mol−1) and E179S mutant (106 kcal mol−1). The significant difference in the enthalpy of the thermal unfolding process could be explained by considering that the thermally denatured state of the F190L mutant is structurally less expanded than the WT and E179S variants. Bioluminescence activity data showed that the maximum characteristic wavelengths of the mutants undergo blue shift as compared with the WT protein. Initial intensity of the F190L and E179S variants was recorded to be 137.5% and 55.9% of the WT protein, respectively. 相似文献