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排序方式: 共有1209条查询结果,搜索用时 78 毫秒
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Sonia Coni Silvia Maria Serrao Zuleyha Nihan Yurtsever Laura Di Magno Rosa Bordone Camilla Bertani Valerio Licursi Zaira Ianniello Paola Infante Marta Moretti Marialaura Petroni Francesca Guerrieri Alessandro Fatica Alberto Macone Enrico De Smaele Lucia Di Marcotullio Giuseppe Giannini Marella Maroder Enzo Agostinelli Gianluca Canettieri 《Cell death & disease》2020,11(12)
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M. Gaudet F. Villani M. Cherubini I. Beritognolo I. Dalla Ragione S. Proietti 《Plant biosystems》2019,153(4):491-497
In central Italy, Prunus cerasus var. austera is cultivated as small stands or scattered trees in marginal areas for the production of jam and wine. Thanks to the healthy attributes of its products and its ability to grow in different environmental conditions, this variety has gained new interest in the development of marginal areas. We assessed the level of the genetic variability of P. cerasus var. austera germplasm from central Italy and identified a ‘core collection’ representative of the present genetic diversity. A total of 161 trees, morphologically identified as var. austera, and one tree, identified as var. caproniana were collected and genotyped by 14 SSRs. Two individuals provided by a commercial plant nursery, one of P. cerasus var. caproniana and one of P. cerasus var. austera, were used as control. Thirteen SSRs presented private alleles in austera. Seven individuals morphologically identified as austera revealed private alleles specific to caproniana. The PCoA and Bayesian clustering analysis showed a main genetic group including var. austera, while a second group included all the caproniana-like genotypes. A core collection of 31 trees (46% of austera genotypes) was selected. This study can be considered as a starting point for future investigations on this variety. 相似文献
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Robert S. Sparkes Hiroyuki Sasaki T. Mohandas Katsuji Yoshioka Ivana Klisak Yoshiyuki Sakaki Camilla Heinzmann Melvin I. Simon 《Human genetics》1987,75(2):151-154
Summary The assignment of the human prealbumin (PALB) gene to chromosome region 18q11–q12.1 has been achieved using a human genomic probe in the study of human-mouse somatic cell hybrids and by in situ hybridization. Because familial amyloidotic polyneuropathy was reported previously to be due to a mutation in prealbumin, it can be inferred that the gene for this disorder also maps to 18q11.2–q12.1. 相似文献
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Analysis of time-lapse cinemicrographs of X-irradiated HeLa S3 cells has shown that the incidence of cell fusion was increased from 0.9% (following 1267 divisions) in control cells to an average of 22% (following 655 divisions) in cells irradiated with 500 rad doses of 220 kv X-rays. The incidence depended on the stage of the generation cycle at which the parent cells were irradiated. It was nearly constant in the first three postirradiation generations. Fusion occurred at all stages of the generation cycle, but preferentially during the first 20%. Cells undergoing fusion progressed more slowly through the generation cycle and had a higher probability of disintegrating than did irradiated cells that did not fuse. The occurrence of fusion was clonally distributed in the population. It took place only between sister (or closely related) cells. Protoplasmic bridges were often visible between sister cells prior to fusion. Giant cells arose only as a result of fusion. The incidence of multipolar divisions, though higher than in unirradiated cells, was only 5.5% in cultures irradiated with 500 rads. Fusion occurred following 85% of the multipolar divisions and was often followed by a multipolar division. 相似文献
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An extended x-ray absorption fine structure study of the high-affinity cation-binding site in the purple membrane. 总被引:1,自引:1,他引:0 下载免费PDF全文
F Sepulcre J Cladera J García M G Proietti J Torres E Padrós 《Biophysical journal》1996,70(2):852-856
The structure of the high-affinity cation-binding site of bacteriorhodopsin was studied using extended x-ray absorption fine structure techniques. The results obtained for Mn2+ in aqueous solution and for the complex BR-Mn2+ (1:1 molar ratio) show great similarities, suggesting that Mn2+, when bound to this site, is coordinated with six atoms of oxygen, forming an octahedral disposition. The interatomic distance between the atoms of oxygen and the Mn2+ was found to be 2.17 A for the complex BR-Mn2+, similar to Mn2+ in solution (2.15 A). In addition, the absence of any other peak at greater distances in the Fourier-transformed spectrum indicates that neither phosphorus nor sulphur atoms are present in the second coordination shell. This suggests that this binding site is located in the protein, discarding the proximity of lipid polar headgroups. 相似文献
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Forslund Kristina Björkman Camilla Abrahamsson Maivor 《Acta veterinaria Scandinavica》1983,24(2):185-199
Plasma cholinesterase (pChE) levels and erythrocyte acetylcholinesterase (eAChE) levels were studied in 6 cows before, during and after parturition (Group I), their calves (Group II), 38 cows suffering from parturient paresis (Group III) and 14 newly delivered non-paretic cows (Group IV). The mean of the pChE level in Group I was 1.5 μkat/1 ± 0.20 before parturition and decreased significantly (P ≦ 0.05) to 1.2 ukat/1 ± 0.16 after parturition. The eAChE level was before parturition ≅ 140 ukat/1 and decreased to ≅ 130 μkat/1 4–5 weeks after parturition. At birth the pChE level was 12.8 ukat/1 ± 5.9 in Group II. After 4 weeks the level had decreased to 2.3 ukat/1 ±0.3. In the bull calves the pChE level started to increase when they were 6 weeks old and reached a level of 5.7 μkat/1 ± 0.6 before slaughter at 6 months of age. The heifers did not show this increase. They had a level of around 2 μkat/1 throughout the investigation. The eAChE level at birth was 119 μkat/1 and increased slowly to a level of 145 μkat/1 at 6 months. No differences between the sexes were found. The cows suffering from parturient paresis had a pChE level of 1.80 μkat/1 ± 0.30 before treatment with calcium (Ca). The level decreased significantly (P ≦ 0.001) after Ca-infusion to a level of 1.67 ukat/1 ±0.29. Group IV had a pChE level of 1.65 μkat/1 ± 0.42 at parturition. Two to 4 months later the cows that had recovered from milk fever had a level of 1.61 μkat/1 ± 0.31 and the control cows 1.66 ukat/1 ± 0.48. No differences between the groups were found for the eAChE level. The findings show that parturition influences the pChE level in cows and that sex influences the pChE level in calves between 6 weeks to at least 6 months of age. Furthermore the elevated pChE level found in the cows suffering from parturient paresis before Ca infusion may be a further sign of a disturbance in the cholinergic system with a special preference to the neuromuscular junctions. 相似文献
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