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排序方式: 共有375条查询结果,搜索用时 15 毫秒
61.
Mohammadreza Nematollahi Mohsen Razeghi Sina Mehdizadeh Hamidreza Tabatabaee Soraya Piroozi Zahra Rojhani Shirazi Ali Rafiee 《PloS one》2016,11(2)
Anterior cruciate ligament injury is a debilitating pathology which may alter lower limb coordination pattern in both intact and affected lower extremities during activities of daily living. Emerging evidence supports the notion that kinematic variables may not be a good indicator to differentiate patients with anterior cruciate ligament deficiency during step descent task. The aim of the present study was to examine alterations in kinematics as well as coordination patterns and coordination variability of both limbs of these patients during a single step descent task. Continuous relative phase technique was used to measure coordination pattern and coordination variability between a group of anterior cruciate ligament deficient (n = 23) and a healthy control group (n = 23). A third order polynomial Curve fitting was utilized to provide a curve that best fitted to the data points of coordination pattern and coordination variability of the healthy control group. This was considered as a reference to compare to that of patient group using nonlinear regression analysis. The results of the present study demonstrated an altered coordination pattern of the supporting shank-thigh and the stepping foot-shank couplings in anterior cruciate ligament deficient subjects. It was further noticed that there was an increased coordination variability in foot-shank and shank-thigh couplings of both supporting and stepping legs. There was no significant difference in the hip, knee and ankle joints kinematics in either side of these patients. Anterior cruciate ligament deficient individuals showed altered strategies in both intact and affected legs, with increased coordination variability. Kinematic data did not indicate any significant difference between the two groups. It could be concluded that more sophisticated dynamic approach such as continuous relative phase would uncover discrepancies between the healthy and anterior cruciate ligament deficient individuals. 相似文献
62.
Soraya Becerra Marta Montes Cristina Hernández-Munain Carlos Su?é 《RNA (New York, N.Y.)》2015,21(3):438-457
The first stable complex formed during the assembly of spliceosomes onto pre-mRNA substrates in mammals includes U1 snRNP, which recognizes the 5′ splice site, and the splicing factors SF1 and U2AF, which bind the branch point sequence, polypyrimidine tract, and 3′ splice site. The 5′ and 3′ splice site complexes are thought to be joined together by protein–protein interactions mediated by factors that ensure the fidelity of the initial splice site recognition. In this study, we identified and characterized PRPF40B, a putative mammalian ortholog of the U1 snRNP-associated yeast splicing factor Prp40. PRPF40B is highly enriched in speckles with a behavior similar to splicing factors. We demonstrated that PRPF40B interacts directly with SF1 and associates with U2AF65. Accordingly, PRPF40B colocalizes with these splicing factors in the cell nucleus. Splicing assays with reporter minigenes revealed that PRPF40B modulates alternative splice site selection. In the case of Fas regulation of alternative splicing, weak 5′ and 3′ splice sites and exonic sequences are required for PRPF40B function. Placing our data in a functional context, we also show that PRPF40B depletion increased Fas/CD95 receptor number and cell apoptosis, which suggests the ability of PRPF40B to alter the alternative splicing of key apoptotic genes to regulate cell survival. 相似文献
63.
Ferreira SM Domingos GP Ferreira Ddos S Rocha TG Serakides R de Faria Rezende CM Cardoso VN Fernandes SO Oliveira MC 《Bioorganic & medicinal chemistry letters》2012,22(14):4605-4608
Osteomyelitis is an infectious disease located in the bone or bone marrow. Long-circulating and pH-sensitive liposomes containing a technetium-99m-labeled antibiotic, ceftizoxime, (SpHL-(99m)Tc-CF) were developed to identify osteomyelitis foci. Biodistribution studies and scintigraphic images of bone infection or non infection-bearing rats that had been treated with these liposomes were performed. A high accumulation in infectious foci and high values in the target-non target ratio could be observed. These results indicate the potential of SpHL-(99m)Tc-CF as a potential agent for the diagnosis of bone infections. 相似文献
64.
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
65.
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
66.
67.
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
68.
Petry CJ Ong KK Michelmore KF Artigas S Wingate DL Balen AH de Zegher F Ibáñez L Dunger DB 《The Journal of steroid biochemistry and molecular biology》2006,98(4-5):199-206
We recently reported association between a coding-region single nucleotide polymorphism (SNP50) in the aromatase gene that encodes a key enzyme in testosterone metabolism, with risk for the development of precocious pubarche and circulating testosterone concentrations in two independent female populations. We have now explored further association with variation in the promoter-region of the aromatase gene. We genotyped six promoter-region haplotype-tag SNPs in young women from Oxford, UK (n = 109), and in girls with precocious pubarche (n = 186) and controls (n = 71) from Barcelona, Spain. Aromatase distal promoter-region variation was associated with plasma testosterone concentrations in both Oxford (r2 = 18.3%, p = 0.01) and Barcelona (r2 = 8.5%, p = 0.03) females. These associations were independent of SNP50, but appeared to be dependent on different SNPs in Oxford (r2 = 13.7%, p = 0.006 with SNPs 11 (p = 0.009), 28 (p = 0.02) and 39 (p = 0.06)) and Barcelona (r2 = 5.9%, p = 0.002 with SNP43 (p = 0.002)) populations. Aromatase distal promoter-region variation was also associated with PCOS symptom score in Oxford women (r2 = 14.5%, p = 0.048), but, unlike SNP50, was not associated with precocious pubarche risk in Barcelona girls. In conclusion, aromatase distal promoter-region variation appears to have functional consequences for plasma testosterone concentrations in females. The variable associations with androgen-related clinical features could possibly reflect the tissue-specific promoters of the aromatase gene. 相似文献
69.
Patricia Messenberg Guimarães Ana Cristina Miranda Brasileiro Karina Proite Ana Claudia Guerra de Araújo Soraya Cristina Macedo Leal-Bertioli Aline Pic-Taylor Felipe Rodrigues da Silva Carolina Vianna Morgante Simone da Graça Ribeiro David John Bertioli 《Tropical plant biology》2010,3(4):183-192
Peanut (Arachis hypogaea) is amongst the most important legume crops in the world. One of its main yield constraints is the root-knot nematode Meloidogyne arenaria. A number of wild Arachis species, including A. stenosperma, are resistant to nematodes, and are a potential source of new resistance alleles for cultivated peanut. Using in silico subtraction of ESTs and macroarray analysis, we identified genes differentially expressed in A. stenosperma roots during its resistance response to M. arenaria. The three most differentially expressed genes [Auxin Repressed Protein (AsARP), Cytokinin Oxidase (AsCKX) and Metallothionein Type 2 (AsMET2)] were further analyzed using northern-blot and showed distinct expression profiles in the resistant A. stenosperma and susceptible A. hypogaea, both after, and sometimes even before, challenge with nematodes. Of the three most differentially expressed genes, AsARP and AsCKX are potentially involved in plant hormonal balance, and AsMET2 may be related to the reactive oxygen reaction triggered by the hypersensitive response (HR). 相似文献
70.
An overview of Iranian mangrove ecosystems, northern part of the Persian Gulf and Oman Sea 下载免费PDF全文
Mohammad Ali Zahe Fatemeh Rouhani Soraya Mohajeri Farshid Bateni Leila Mohajeri 《农业工程》2010,30(4):240-244
Iranian mangrove forests occur between longitude 25°19′ and 27°84′, in the north part of the Persian Gulf and Oman Sea. In 2002, it was estimated that 93.37 km2 of Iranian shorelines were covered with mangrove forests, with the largest area (67.5 km2) occurring between the Khamir Port and the northwest side of Qeshm Island, and the smallest area (0.01 km2) in the Bardestan estuary. Only two species of mangrove are found in the Persian Gulf: Avicennia marina from Avicenniaceae and Rhizophora macrunata from Rhizophoraceae. A. marina is the dominant specie in these forests whereas Rh. macrunata is found only in the Sirik region. Overexploitation of mangrove leaves and oil pollution are the main causes of mangrove destruction in this region. 相似文献