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1.
Dulce E. Oliveira Ana Lúcia C. Santos Neto Anita D. Panek 《Analytical biochemistry》1981,113(1):188-192
A quantitative in situ assay of yeast α-glucosidase involving permeabilization of the cells by freezing and thawing is described. The assay was applied to different strains in different physiological states and was shown to give results comparable to those obtained with total cell homogenates. The primary advantage of the in situ assay was the possibility of analyzing a large number of samples from the same culture during a growth curve using a very reduced cell mass. 相似文献
2.
Zavala-Ortiz Daniel Arturo Ebel Bruno Guedon Emmanuel Marc Annie Barradas-Dermitz Dulce María Hayward-Jones Patricia Margaret Aguilar-Uscanga María Guadalupe 《Bioprocess and biosystems engineering》2020,43(4):747-752
Bioprocess and Biosystems Engineering - Plant suspension culture is attracting interest as a promising platform to produce biological medicines due to the absence of virus, prions or DNA related to... 相似文献
3.
Espinoza Dulce O. Molina-Freaner Francisco Tinoco-Ojanguren Clara 《Plant Ecology》2020,221(4):255-264
Plant Ecology - Buffel grass (Cenchrus ciliaris L.) is an African grass used as forage for livestock that is also invasive. Several methods have been evaluated to remove invasive buffel grass, but... 相似文献
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Eduardo Eizirik Sandro L. Bonatto Warren E. Johnson Peter G. Crawshaw Jr. Jean Cristophe Vié Dulce M. Brousset Stephen J. O'Brien Francisco M. Salzano 《Journal of molecular evolution》1998,47(5):613-624
The ocelot (Leopardus pardalis) and margay (L. wiedii) are sister-species of Neotropical cats which evolved from a lineage that migrated into South America during the formation
of the Panamanian land bridge 3–5 million years ago. Patterns of population genetic divergence of each species were studied
by phylogenetic analyses of mitochondrial DNA (mtDNA) control region sequences in individuals sampled across the distribution
of these taxa. Abundant genetic diversity and remarkably concordant phylogeographic partitions for both species were observed,
identifying parallel geographic regions which likely reflect historical faunal barriers. Inferred aspects of phylogeography,
population genetic structure, and demographic history were used to formulate conservation recommendations for these species.
In addition, observed patterns of sequence variation provided insight into the molecular evolution of the mtDNA control region
in closely related felids.
Received: 26 January 1998 / Accepted: 14 May 1998 相似文献
7.
Armando Aguirre Mario Vallejo-Marín Lizandra Salazar-Goroztieta Dulce M. Arias Rodolfo Dirzo 《Biotropica》2007,39(1):79-86
Dioecy, the segregation of male and female structures among individuals, is widespread in tropical plants, encompassing 10–30 percent of species in some sites. In many cases, interindividual sex separation is not complete, as individual plants, although nominally dioecious, may produce both types of reproductive structures. A common form of this sexual variation is the production of female structures in otherwise male individuals, commonly referred to as fruiting males. Here we report the existence of fruiting males in the dioecious tropical tree Jacaratia mexicana (Caricaceae). We show that fruiting males can constitute up to 45 percent of all males in some populations of a tropical forest in Southern Mexico. In order to determine the functional significance of fruiting males for the breeding system of J. mexicana , we compared the relative performance of male- and female-borne seeds. Our results show that seeds from fruiting males are three times less likely to germinate and survive than seeds from female trees. Based on relative seed fitness data, and sex ratios in natural populations, we estimate that 6–15 percent of the genes contributed by fruiting males to the next generation are transmitted via ovules, meaning that morphological variation in gender is at least partially accompanied by functional gender variation. Finally, our seed fitness estimates for fruiting males suggest that fruiting males will not replace female plants in natural populations.
Abstract in Spanish is available at http://www.blackwell-synergy.com/loi/btp . 相似文献
Abstract in Spanish is available at http://www.blackwell-synergy.com/loi/btp . 相似文献
8.
Ademir Neves Cludio N. Verani Marcos A. de Brito Ivo Vencato Antnio Mangrich Glaucius Oliva Dulce D.H.F. Souza Alzir A. Batista 《Inorganica chimica acta》1999,290(2):2221-212
Copper(II) complexes were synthesized and characterized by means of elemental analysis, IR and visible spectroscopies, EPR and electrochemistry, as well as X-ray structure crystallography. The group consists of discrete mononuclear units with the general formula [Cu(II)(Hbpa)2](A)2·nH2O, where Hbpa=(2-hydroxybenzyl-2-pyridylmethyl)amine and A=ClO4 −, n=2 (1), CH3COO−, n=3 (2), NO3 −, n=2 (3) and SO4 2−, n=3 (4). The structures of the ligand Hbpa and complex 1 have been determined by X-ray crystallography. Complexes 1–4 have had their UV–Vis spectra measured in both MeCN and DMF. It was observed that the compounds interact with basic solvents, such that molecules coordinate to the metal in axial positions in which phenol oxygen atoms are coordinated in the protonated forms. The values were all less than 1000 M−1 cm−1. EPR measurements on powdered samples of 1–3 gave g/A values between 105 and 135 cm−1, typical for square planar coordination environments. Complex 4·3H2O exhibits a behaviour typical for tetrahedral coordination. The electrochemical behaviour for complexes 1 and 2 was studied showing irreversible redox waves for both compounds. 相似文献
9.
Dulce?A.?OliveiraEmail author Marco?P.?L.?Parente Bego?a?Calvo Teresa?Mascarenhas Renato?M.?Natal?Jorge 《Biomechanics and modeling in mechanobiology》2016,15(6):1523-1534
Episiotomy is still a controversy issue among physicians, despite the enormous growth of clinical research. Therefore, the potential of numerical modeling of anatomical structures to simulate biomechanical processes was exploited to realize quantitatively the real effects of the episiotomy and its consequences on the pelvic floor muscle. As such, a numerical model was used composed of pelvic floor muscles, a surface delimiting the anterior region, and a fetus body. A normal vaginal delivery without and with different episiotomies was simulated with the fetus in vertex presentation and occipitoanterior position. According to our numerical results, a mediolateral episiotomy has a protective effect, reducing the stress on the muscles, and the force required to delivery successfully up to 52.2 %. The intervention also has benefits on muscle injury, reducing the damage to a small zone. This study demonstrates the feasibility of using a computational modeling approach to study parturition, namely the capability to isolate and evaluate the mechanical significance of a single feature. It must, however, be taken into account that the numerical model does not assess problems that may occur as blood loss, infections and others, so it is necessary to examine whether the benefits of an intervention outweigh the risks. 相似文献
10.
High levels of extracellular ATP lead to chronic inflammatory response in melanoma patients 下载免费PDF全文