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排序方式: 共有660条查询结果,搜索用时 46 毫秒
1.
D S Faffe G H Silva P M Kurtz E M Negri V L Capelozzi P R Rocco W A Zin 《Journal of applied physiology》2001,90(4):1400-1406
The dynamic mechanical properties of lung tissue and its contents of collagen and elastic fibers were studied in strips prepared from mice instilled intratracheally with saline (C) or silica [15 (S15) and 30 days (S30) after instillation]. Resistance, elastance, and hysteresivity were studied during oscillations at different frequencies on S15 and S30. Elastance increased from C to silica groups but was similar between S15 and S30. Resistance was augmented from C to S15 and S30 and was greater in S30 than in S15 at higher frequencies. Hysteresivity was higher in S30 than in C and S15. Silica groups presented a greater amount of collagen than did C. Elastic fiber content increased progressively along time. This increment was related to the higher amount of oxytalan fibers at 15 and 30 days, whereas elaunin and fully developed elastic fibers were augmented only at 30 days. Silicosis led not only to pulmonary fibrosis but also to fibroelastosis, thus assigning a major role to the elastic system in the silicotic lung. 相似文献
2.
In prokaryotes, the RecA protein plays a pivotal role in homologous recombination, catalyzing the transfer of a single DNA
strand into an homologous molecule. Structural homologs of the bacterial RecA protein, called Rad51, have been found in different
eukaryotes (from yeast to man), suggesting a certain level of conservation in recombination pathways among living organisms.
We have cloned the homolog of RAD51 in Caenorhabditis elegans. The CeRAD51 gene is transcribed into two alternative mRNAs and potentially codes for two proteins of 395 and 357 amino acids in length,
respectively. We discuss the evolutionary implications of these findings.
Received: 26 May 1998 / Accepted: 18 August 1998 相似文献
3.
4.
Evelina Colacino Antonella Converso Antonio De Nino Antonella Leggio Angelo Liguori Loredana Maiuolo 《Nucleosides, nucleotides & nucleic acids》2013,32(4-5):581-583
Abstract The complete set of the 4′-aza analogues of 2′,3′-dideoxynucleosides was synthesized by cycloaddition of N-tetrahydropiranyl or N-trityl methylene nitrones on suitably protected vinyl nucleobases. The convertible nucleoside approach was used in the preparation of cytosine and 5-methyl cytosine analogues. 相似文献
5.
D. Lupi M. L. Giudici C. Cenghialta A. Rocco C. Jucker M. Colombo 《Journal of Applied Entomology》2013,137(5):355-364
Italy is the largest rice‐producing country in the European Union. In Italy, only japonica cultivars are listed in the Italian National Register. Almost all of the rice production is concentrated in the Po Valley, where the rice water weevil Lissorhoptrus oryzophilus Kuschel was first detected and settled. This study investigated the performance of this pest in terms of feeding, reproduction and plant injury on 10 rice cultivars chosen among the most widely grown in Italy. No‐choice experiments were conducted to evaluate the plant susceptibility to larval attack and to find out how cultivars can influence the adult leaf area consumption. The results gave evidence of different types of attack depending on the density of the insect (0.6 adults/plant vs. 0.9 adults/plant), the cultivar type and climatic conditions. Different cultivars with the same level of infestation gave different results in terms of productivity. Production was significantly affected by the larval presence in 4 of the 10 cultivars tested. A different population structure reflected a different damage severity. Statistically different values for total adult leaf area consumption were found according to adult female age and to the cultivar. 相似文献
6.
Emre Brookes Borries Demeler Camillo Rosano Mattia Rocco 《European biophysics journal : EBJ》2010,39(3):423-435
The interpretation of solution hydrodynamic data in terms of macromolecular structural parameters is not a straightforward
task. Over the years, several approaches have been developed to cope with this problem, the most widely used being bead modeling
in various flavors. We report here the implementation of the SOMO (SOlution MOdeller; Rai et al. in Structure 13:723–734,
2005) bead modeling suite within one of the most widely used analytical ultracentrifugation data analysis software packages, UltraScan
(Demeler in Modern analytical ultracentrifugation: techniques and methods, Royal Society of Chemistry, UK, 2005). The US-SOMO version is now under complete graphical interface control, and has been freed from several constraints present
in the original implementation. In the direct beads-per-atoms method, virtually any kind of residue as defined in the Protein
Data Bank (e.g., proteins, nucleic acids, carbohydrates, prosthetic groups, detergents, etc.) can be now represented with
beads whose number, size and position are all defined in user-editable tables. For large structures, a cubic grid method based
on the original AtoB program (Byron in Biophys J 72:408–415, 1997) can be applied either directly on the atomic structure, or on a previously generated bead model. The hydrodynamic parameters
are then computed in the rigid-body approximation. An extensive set of tests was conducted to further validate the method,
and the results are presented here. Owing to its accuracy, speed, and versatility, US-SOMO should allow to fully take advantage
of the potential of solution hydrodynamics as a complement to higher resolution techniques in biomacromolecular modeling. 相似文献
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8.
Jons A. Aguirre‐Liguori Brandon S. Gaut Juan Pablo Jaramillo‐Correa Maud I. Tenaillon Salvador Montes‐Hernndez Felipe García‐Oliva Sarah J. Hearne Luis E. Eguiarte 《Molecular ecology》2019,28(11):2814-2830
Patterns of genomic divergence between hybridizing taxa can be heterogeneous along the genome. Both differential introgression and local adaptation may contribute to this pattern. Here, we analysed two teosinte subspecies, Zea mays ssp. parviglumis and ssp. mexicana, to test whether their divergence has occurred in the face of gene flow and to infer which environmental variables have been important drivers of their ecological differentiation. We generated 9,780 DArTseqTM SNPs for 47 populations, and used an additional data set containing 33,454 MaizeSNP50 SNPs for 49 populations. With these data, we inferred features of demographic history and performed genome wide scans to determine the number of outlier SNPs associated with climate and soil variables. The two data sets indicate that divergence has occurred or been maintained despite continuous gene flow and/or secondary contact. Most of the significant SNP associations were to temperature and to phosphorus concentration in the soil. A large proportion of these candidate SNPs were located in regions of high differentiation that had been identified previously as putative inversions. We therefore propose that genomic differentiation in teosintes has occurred by a process of adaptive divergence, with putative inversions contributing to reduced gene flow between locally adapted populations. 相似文献
9.
Christopher W. Schmidt Ashley Remy Rebecca Van Sessen John Willman Kristin Krueger Rachel Scott Patrick Mahoney Jeremy Beach Jaqueline McKinley Ruggero D'Anastasio Laura Chiu Michele Buzon J. Rocco De Gregory Susan Sheridan Jacqueline Eng James Watson Haagen Klaus Pedro Da-Gloria Jeremy Wilson Abigail Stone Paul Sereno Jessica Droke Rose Perash Christopher Stojanowski Nicholas Herrmann 《American journal of physical anthropology》2019,169(2):207-226
10.
Y‐craniosynostosis by premature fusion of the metopic and coronal sutures: A new nosological entity or a variety of Saethre‐Chotzen syndrome? 下载免费PDF全文