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排序方式: 共有409条查询结果,搜索用时 500 毫秒
61.
Dallal Chergui Soraya Akretche-Kelfat Lynda Lamoudi Mamoon Al-Rshaidat Farida Boudjelal Hamid Ait-Amar 《Saudi Journal of Biological Sciences》2021,28(12):7134-7141
In the present work, the GHARS and the MECH DEGLA downgraded date varieties were used in a fermentation medium in order to produce citric acid by the Aspergillus niger. The biochemical characteristics of the dates were investigated, along with the chemical and physical characteristics of the solutions of both samples. The analyzed parameters included the moisture and sugar content, the ash residual, the pH values, and the electrical conductivity. The effect of the following fermentation parameters was studied: initial pH, temperature, incubation period, and methanol. For the GHARS and MECH DEGLA date varieties respectively, the ash residual measured at 1.90% and 2.47%. For each date variety, the moisture and total sugars were measured at 11.59% and 85%, for the GHARS, and 12.82% and 80.47% for the MECH DEGLA. Citric acid production using either of the two varieties of dates showed a high yield in a short time.The obtained results showed that the highest production of citric acid by both medium of dates was achieved at the initial pH value of 3.0, temperature 30 °C, and an incubation period of 8 days. Also, the maximum amount of citric acid was produced when both mediums contained 4% of methanol. Both varieties of dates showed a good yield for the citric acid and can be used as a culture medium since they are economic and ensure good growth for the Aspergillus niger. 相似文献
62.
Liliane Viana Pires Adriana Aparecida Siviero-Miachon Angela Maria Spinola-Castro José Alexandre Coelho Pimentel Luciana Sigueta Nishimura Carla Soraya Costa Maia Silvia Maria Franciscato Cozzolino 《Biological trace element research》2017,176(2):217-224
Studies about selenium status in patients with Turner syndrome (TS) are non-existent in the literature. The aim of this study was to evaluate selenium status in patients with TS, while considering the different ages of the studied population and the relation with body composition. In total, 33 patients with TS were evaluated and grouped according to their developmental stages (children, adolescents, and adults). Selenium concentrations in their plasma, erythrocytes, urine, and nails were determined by using hydride generation atomic absorption spectrometry and erythrocyte glutathione peroxidase activity were measured by using Randox commercial kits. Additionally, height, weight, body fat percentage, waist circumference, and waist-height ratio were measured to characterize the patients. No differences in the selenium concentrations in the plasma, erythrocyte, urine, and nails or in the glutathione peroxidase activity were observed among the age groups (p > 0.05). The evaluated selenium levels were less than the established normal ones. The patients with larger waist circumference, body fat percentage, body mass index, and waist-height ratio showed lower glutathione peroxidase enzyme activity (p = 0.023). The present study shows that most patients with TS are deficient in selenium and that those with a greater accumulation of body fat have a lower GPx activity. 相似文献
63.
Soraya Guichard Christian Gary Cherubino Leonardi Nadia Bertin 《Journal of Plant Growth Regulation》2005,24(3):201-213
The influence of air vapor pressure deficit (VPD) and plant fruit load on the expansion and water relations of young tomato
fruits grown in a glasshouse were evaluated under summer Mediterranean conditions. The contributions of phloem, xylem and
transpiration fluxes to the fruit volume increase were estimated at an hourly scale from the growth curves of intact, heat-girdled
and detached fruits, measured using displacement transducers. High VPD conditions reduced the xylem influx and increased the
fruit transpiration, but hardly affected the phloem influx. Net water accumulation and growth rate were reduced, and a xylem
efflux even occurred during the warmest and driest hours of the day. Changes in xylem flux could be explained by variations
in the gradient of water potential between stem and fruit, due to changes in stem water potential. Misting reduced air VPD
and alleviated the reduction in fruit volume increase through an increase in xylem influx and a decrease in fruit transpiration.
Under low fruit load, the competition for assimilates being likely reduced, the phloem flux to fruits increased, similarly
to the xylem and transpiration fluxes, without any changes in the fruit water potential. However, different diurnal dynamics
among treatments assume variable contributions of turgor and osmotic pressure in F3 and F6 fruits, and hypothetical short-term
variations in the water potential gradient between stem and fruit, preventing xylem efflux in F3 fruits. 相似文献
64.
65.
Modulation of stress and virulence in Listeria monocytogenes 总被引:1,自引:0,他引:1
66.
Angelo PC Nunes-Silva CG Brígido MM Azevedo JS Assunção EN Sousa AR Patrício FJ Rego MM Peixoto JC Oliveira WP Freitas DV Almeida ER Viana AM Souza AF Andrade EV Acosta PO Batista JS Walter ME Leomil L Anjos DA Coimbra RC Barbosa MH Honda E Pereira SS Silva A Pereira JO Silva ML Marins M Holanda FJ Abreu RM Pando SC Gonçalves JF Carvalho ML Leal-Mesquita ER da Silveira MA Batista WC Atroch AL França SC Porto JI Schneider MP 《Plant cell reports》2008,27(1):117-124
Guarana (Paullinia cupana var. sorbilis) is a plant native to the central Amazon basin. Roasted seed extracts have been used as medicinal beverages since pre-Colombian
times, due to their reputation as stimulants, aphrodisiacs, tonics, as well as protectors of the gastrointestinal tract. Guarana
plants are commercially cultivated exclusively in Brazil to supply the national carbonated soft-drink industry and natural
product stores around the world. In this report, we describe and discuss the annotation of 15,387 ESTs from guarana seeded-fruits,
highlighting sequences from the flavonoid and purine alkaloid pathways, and those related to biotic stress avoidance. This
is the largest set of sequences registered for the Sapindaceae family. 相似文献
67.
68.
Fermin M. Sanchez-Guijo Juan F. Blanco Graciela Cruz Sandra Muntion Maria Gomez Soraya Carrancio Olga Lopez-Villar Maria-Victoria Barbado Luis-Ignacio Sanchez-Abarca Belén Blanco Jesus G. Briñon Maria-Consuelo del Cañizo 《Cell and tissue research》2009,336(3):501-507
Trabecular bone fragments from femoral heads are sometimes used as bone grafts and have been described as a source of mesenchymal
progenitor cells. Nevertheless, mesenchymal stromal cells (MSC) from trabecular bone have not been directly compared with
MSC obtained under standard conditions from iliac crest aspiration of the same patients. This is the ideal control to avoid
inter-individual variation. We have obtained MSC by a novel method (grinding bone fragments with a bone mill without enzymatic
digestion) from the femoral heads of 11 patients undergoing hip replacement surgery and compared them with MSC obtained by
standard iliac crest aspiration of bone marrow from the same patients. We have shown that trabecular bone MSC obtained by
mechanically fragmented femoral heads fulfil the immunophenotypic and multilineage (adipogenic, osteogenic and chondrogenic)
differentiation criteria used to define MSC. We have also differentially compared cellular yields, growth kinetics, cell cycle
assessment, and colony-forming unit-fibroblast content of MSC from both sources and conclude that these parameters do not
significantly differ. Nevertheless, the finding of slight differences, such as a higher expression of the immature marker
CD90, a lower expansion time through the different passages, and a higher percentage of cycling cells in the trabecular bone
MSC, warrants further studies with the isolation method proposed here in order to gain further knowledge of the status of
MSC in this setting.
The present study was partially supported by grant HUS01B07 from the Consejería de Educación and by grant SAN196/SA13/07 from
the Consejería de Sanidad, Junta de Castilla y León, Spain. 相似文献
69.
Andrew D. Morley Peter W. Kenny Brenda Burton Robert A. Heald Philip A. MacFaul Julia Mullett Ken Page Soraya S. Porres Lyn Rosenbrier Ribeiro Phil Smith Stuart Ward Tina J. Wilkinson 《Bioorganic & medicinal chemistry letters》2009,19(6):1658-1661
A series of pyrimidine nitrile inhibitors of Cathepsin K with reduced glutathione reactivity has been identified and Molecular Core Matching (MoCoM) has been used to quantify the effect of an amino substituent at C5. 相似文献
70.
Maria Angela Orsi Margarida Maria H. Zaroni Luciano Doretto Júnior Soraya Cecilia Albieri Camillo Simone Alves Mendes Ribeiro Fernando Rosado Spilki Maria da Glria Buzinaro Clarice Weis Arns 《Biologicals》2009,37(4):252-258
The thermostability (TS) and efficacy offered by live vaccines against Newcastle disease strains B1, La Sota, VG-GA and Ulster, produced or imported by four Brazilian laboratories, were evaluated during their validity period. Kinetic profiles were obtained from samples conserved in refrigerators during 0, 4, 8, 12, 16, 20 and 24 months after their manufacturing. The statistical analysis of the vaccine titre effect obtained by the fresh air (FA) method showed that the vaccine profiles were parallel and coincident, presenting a significant descending trend. The vaccine titres and efficiency proofs at the end of the validity period were above the level of legislation requirements and showed an average loss in titre of 0.40 and 0.66 log10, within the first and second validity years, respectively. The titre obtained by TS, within the month after manufacturing, had no significant difference from the titre obtained by FA within 24 months after manufacturing, being their pairs of observations positively correlated (r = 0.49, p = 0.0003), showing that the TS method, which anticipates the vaccines' performance at the end of the validity period, can substitute the FA method 24 months after manufacturing. 相似文献