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91.
Naga VA Kommuri Sri Lakshmi S Kollepara E Saulitis MA Siddiqui 《Indian pacing and electrophysiology journal》2010,10(1):49-54
Evaluation of defibrillation threshold is a standard of care during implantation of implantable cardioverter defibrillator. High defibrillation thresholds are often encountered and pose a challenge to electrophysiologists to improve the defibrillation threshold. We describe a case series where defibrillation thresholds were improved after implanting a defibrillation lead in the azygos vein. 相似文献
92.
93.
Vittorio Dal Piaz Maria Carla Castellana Claudia Vergelli Maria Paola Giovannoni Amadeu Gavaldà Victor Segarra 《Journal of enzyme inhibition and medicinal chemistry》2013,28(4):227-233
A series of pyrazolo[3,4-d]pyridazinones and analogues, potentially useful as peripheral vasodilators, were synthesized and evaluated as inhibitors of PDE5 extracted from human platelets. Several of them showed IC 50 values in the range 0.14-1.4 μM. A good activity and selectivity profile versus PDE6 was found for compound 11e (6-benzyl-3-methyl-1-isopropyl-4-phenylpyrazolo[3,4-d]pyridazin-7(6H)-one). Structure-activity relationship studies demonstrated the essential role played by the benzyl group at position-6 of the pyrazolopyridazine system. Other types of pyridazinones fused with five and six membered heterocycles (pyrrole, isoxazole, pyridine and dihydropyridine), as well as some open models were prepared and evaluated. Besides the pyrazole, the best fused systems proved to be isoxazole and pyridine. 相似文献
94.
In behavioural studies it has been common to quantify plumage colours or ornaments over a range of dates and link them to fitness characteristics without accounting for seasonal changes in these traits. Such changes are likely to be widespread among birds, yet we lack assessments of this variability within individuals. We studied both within‐ and between‐individual temporal changes in Great Tit Parus major ornaments, specifically the melanin‐based black breast stripe and the pigment‐free white cheek patch. During the non‐breeding season both ornaments varied. In juveniles and adult females, the area of the breast stripe first rose and then, from near the end of December, decreased. In adult males there was a linear decrease. In the cheek patch, the irregularity of the cheek borders showed either a linear (adults) or a non‐linear (juveniles) increase as the season progressed. In individuals repeatedly sampled during the same winter, the decrease in the size of the breast stripe was larger for males than females and there was an overall decrease in the regularity of the cheek borders. There was no relationship between the size of the breast stripe and the white cheek patch irregularities or the cheek patch area. These results imply that more attention should be paid to quantification, within individuals, of the components of expression of phenotypic traits. In addition, we suggest that further research should focus on explaining the causes and functions of ornament change. 相似文献
95.
Montserrat Papaceit Carmen Segarra Montserrat Aguadé 《Evolution; international journal of organic evolution》2013,67(1):66-79
Drosophila subobscura is a paleartic species of the obscura group with a rich chromosomal polymorphism. To further our understanding on the origin of inversions and on how they regain variation, we have identified and sequenced the two breakpoints of a polymorphic inversion of D. subobscura—inversion 3 of the O chromosome—in a population sample. The breakpoints could be identified as two rather short fragments (~300 bp and 60 bp long) with no similarity to any known transposable element family or repetitive sequence. The presence of the ~300‐bp fragment at the two breakpoints of inverted chromosomes implies its duplication, an indication of the inversion origin via staggered double‐strand breaks. Present results and previous findings support that the mode of origin of inversions is neither related to the inversion age nor species‐group specific. The breakpoint regions do not consistently exhibit the lower level of variation within and stronger genetic differentiation between arrangements than more internal regions that would be expected, even in moderately small inversions, if gene conversion were greatly restricted at inversion breakpoints. Comparison of the proximal breakpoint region in species of the obscura group shows that this breakpoint lies in a small high‐turnover fragment within a long collinear region (~300 kb). 相似文献
96.
Among the cellular responses to photodamage initiated by photodynamic therapy (PDT) are autophagy and apoptosis. While autophagy is a reversible process that can be both a survival and a death pathway, apoptosis is irreversible, leading only to cell death. In this study, we followed the fate of mouse leukemia L1210 cells after photodamage to the endoplasmic reticulum (ER) using a porphycene photosensitizer, where Bcl-2 was among the PDT targets. In wild-type cells, we observed a rapid wave of autophagy, presumed to represent the recycling of some damaged organelles, followed by apoptosis. Using shRNA technology, we created a Bax knockdown line (L1210/Bax(-)). In the latter cell line, we found a marked decrease in apoptosis after photodamage or pharmacologic inactivation of Bcl-2 function, but this did not affect PDT efficacy. Loss of viability was associated with a highly-vacuolated morphology consistent with autophagic cell death. Previous studies indicated pro-survival attributes of autophagy after low-dose PDT, suggesting that autophagy may be responsible for the 'shoulder' on the dose-response curve. It appears that attempts at extensive recycling of damaged organelles are associated with cell death, and that this phenomenon is amplified when apoptosis is suppressed. 相似文献
97.
Genome sequence comparison across the Drosophila genus revealed that some fixed inversion breakpoints had been multiply reused at this long timescale. Cytological studies of Drosophila inversion polymorphism had previously shown that, also at this shorter timescale, some breakpoints had been multiply reused. The paucity of molecularly characterized polymorphic inversion breakpoints has so far precluded contrasting whether cytologically shared breakpoints of these relatively young inversions are actually reused at the molecular level. The E chromosome of Drosophila subobscura stands out because it presents several inversion complexes. This is the case of the E1+2+9+3 arrangement that originated from the ancestral Est arrangement through the sequential accumulation of four inversions (E1, E2, E9 and E3) sharing some breakpoints. We recently identified the breakpoints of inversions E1 and E2, which allowed establishing reuse at the molecular level of the cytologically shared breakpoint of these inversions. Here, we identified and sequenced the breakpoints of inversions E9 and E3, because they share breakpoints at sections 58D and 64C with those of inversions E1 and E2. This has allowed establishing that E9 and E3 originated through the staggered-break mechanism. Most importantly, sequence comparison has revealed the multiple reuse at the molecular level of the proximal breakpoint (section 58D), which would have been used at least by inversions E2, E9 and E3. In contrast, the distal breakpoint (section 64C) might have been only reused once by inversions E1 and E2, because the distal E3 breakpoint is displaced >70 kb from the other breakpoint limits. 相似文献
98.
99.
Prat M Buil MA Fernández MD Castro J Monleón JM Tort L Casals G Ferrer M Huerta JM Espinosa S López M Segarra V Gavaldà A Miralpeix M Ramos I Vilella D González M Córdoba M Cárdenas A Antón F Beleta J Ryder H 《Bioorganic & medicinal chemistry letters》2011,21(11):3457-3461
Novel quaternary ammonium derivatives of N,N-disubstituted (3R)-quinuclidinyl carbamates have been identified as potent M3 muscarinic antagonists with long duration of action in an in vivo model of bronchoconstriction. These compounds have also presented a high level of metabolic transformation (human liver microsomes). The synthesis, structure-activity relationships and biological evaluation of these compounds are reported. 相似文献
100.
Artificial intelligence in pest insect monitoring 总被引:1,自引:0,他引:1
PETER FEDOR JAROMÍR VAŇHARA JOSEF HAVEL IGOR MALENOVSKÝ IAN SPELLERBERG 《Systematic Entomology》2009,34(2):398-400
Abstract Global problems of hunger and malnutrition induced us to introduce a new tool for semi‐automated pest insect identification and monitoring: an artificial neural network system. Multilayer perceptrons, an artificial intelligence method, seem to be efficient for this purpose. We evaluated 101 European economically important thrips (Thysanoptera) species: extrapolation of the verification test data indicated 95% reliability at least for some taxa analysed. Mainly quantitative morphometric characters, such as head, clavus, wing, ovipositor length and width, formed the input variable computation set in a Trajan neural network simulator. The technique may be combined with digital image analysis. 相似文献