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111.
CA Kalva-Filho EZ Campos VL Andrade ASR Silva AM Zagatto MCS Lima M Papoti 《Biology of sport / Institute of Sport》2015,32(4):333-337
The aims of the present study were to investigate the relationship of aerobic and anaerobic parameters with 400 m performance, and establish which variable better explains long distance performance in swimming. Twenty-two swimmers (19.1±1.5 years, height 173.9±10.0 cm, body mass 71.2±10.2 kg; 76.6±5.3% of 400 m world record) underwent a lactate minimum test to determine lactate minimum speed (LMS) (i.e., aerobic capacity index). Moreover, the swimmers performed a 400 m maximal effort to determine mean speed (S400m), peak oxygen uptake () and total anaerobic contribution (CANA). The CANA was assumed as the sum of alactic and lactic contributions. Physiological parameters of 400 m were determined using the backward extrapolation technique ( and alactic contributions of CANA) and blood lactate concentration analysis (lactic anaerobic contributions of CANA). The Pearson correlation test and backward multiple regression analysis were used to verify the possible correlations between the physiological indices (predictor factors) and S400m (independent variable) (p < 0.05). Values are presented as mean ± standard deviation. Significant correlations were observed between S400m (1.4±0.1 m·s-1) and LMS (1.3±0.1 m·s-1; r = 0.80), (4.5±3.9 L·min-1; r = 0.72) and CANA (4.7±1.5 L·O2; r= 0.44). The best model constructed using multiple regression analysis demonstrated that LMS and explained 85% of the 400 m performance variance. When backward multiple regression analysis was performed, CANA lost significance. Thus, the results demonstrated that both aerobic parameters (capacity and power) can be used to predict 400 m swimming performance. 相似文献
112.
113.
Eman M. Hussein Shahira A. Ahmed Amira B. Mokhtar Sherine M. Elzagawy Samah H. Yahi Abdalla M. Hussein Farid El-Tantawey 《Parasitology international》2018,67(6):666-674
Outbreaks of Cyclospora cayetanensis infection have been linked to consumption of food and water contaminated by oocysts that can survive both physical and chemical disinfectants. Magnesium oxide (MgO) nanoparticles (NPs) can be potentially used in food as bactericides. In this study, C. cayetanensis pre- and post-sporulated oocysts were exposed to MgO NPs with different doses ranging from 1.25–25?mg/ml. With comparison to control, the antiprotozoal activity of MgO NPs was evaluated by identifying the median effective concentration dose (EC50), lethal concentration dose (LC90), microscopically changes on treated oocysts and rates of sporulation. Among pre- and post-sporulated oocysts, MgO NPs?≥?EC50 was observed after 24?h at concentrations 10 and 12.5?mg/ml, respectively, while?≥?LC90 was observed after 24?h, 48?h and 72?h at concentrations 15, 12.5 and 10?mg/ml, respectively. MgO NPs treated oocysts showed abnormal morphological changes such as an increase in size, wall injury, deposition of vacuolated homogenous particles in the cytoplasm, evacuation of oocyst's contents, and collapse. Sporocysts of treated oocysts were noticed to be peripherally shifted. Sporulation failure of treated oocysts achieved ≥90% after 24?h and 72?h of incubation with 15 and 12.5?mg/ml, respectively, while it was 10.1% among non-treated. All the differences were statistically significant. Our results demonstrated that MgO NPs has a significant anti-Cyclospora effect on both unsporulated and sporulated oocysts, especially considering that it could be biologically synthesized, that way it can be used safely as a preventive agent in food and water disinfectant treatment. 相似文献
114.
Bhattasali Onita Thompson Lester D.R. Abdalla Iman A. Chen Jergin Iganej Shawn 《Reports of Practical Oncology and Radiotherapy》2018,23(5):451-457
Aim: To perform a comparison of Cisplatin vs. Cetuximab in p16-positive oropharyngeal squamous cell carcinoma (OPSCC) in the context of the revised HPV-based staging.Background: Previous reports comparing these agents in head and neck cancer have included heterogenous disease and p16-status.Materials and methods: A retrospective review was conducted from 2006 to 2016 of patients with p16-positive OPSCC who underwent definitive radiotherapy concurrent with either triweekly Cisplatin (n?=?251) or Cetuximab (n?=?40). AJCC 8th Edition staging was adapted.Results: Median follow-up for surviving patients was 40 months. On multivariate analysis for all-comers, comparing Cisplatin and Cetuximab, 3-year locoregional recurrence (LRR): 6% vs. 16% (p?=?0.07), 3-year distant metastasis (DM): 8% vs. 21% (p?=?0.04), 3-year overall recurrence rate (ORR): 11% vs. 29% (p?=?0.01), and 3-year cause-specific survival (CSS): 94% vs. 79% (p?=?0.06), respectively. On stage-based subgroup analysis, for stage III disease, 3-year LRR: 5% vs. 10% (p?=?0.51), 3-year DM: 7% vs. 16% (p?=?0.32), 3-year ORR: 10% vs. 23% (p?=?0.15), and 3-year CSS: 95% vs. 82% (p?=?0.38). For stage III disease, 3-year LRR: 10% vs. 40% (p?=?0.07), 3-year DM: 9% vs. 43% (p?=?0.07), 3-year ORR: 15% vs. 55% (p?=?0.04), and 3-year CSS: 94% vs. 57% (p?=?0.048).Conclusions: When given concurrently with radiotherapy, Cetuximab and triweekly Cisplatin demonstrated comparable efficacy for AJCC 8th Edition stage I–II p16-positive OPSCC. However, Cetuximab appeared to be associated with higher rates of treatment failure and cancer-related deaths in stage III disease. Upon availability of the RTOG 1016 trial results, analysis based on the revised HPV-based staging should be performed to confirm these findings. 相似文献
115.
Li Li Osama Abdalla Abdelshafy Mohamad Jinbiao Ma Ariel D. Friel Yangui Su Yun Wang Zulpiya Musa Yonghong Liu Brian P. Hedlund Wenjun Li 《Antonie van Leeuwenhoek》2018,111(10):1735-1748
Little is known about the composition, diversity, and geographical distribution of bacterial communities associated with medicinal plants in arid lands. To address this, a collection of 116 endophytic bacteria were isolated from wild populations of the herb Glycyrrhiza uralensis Fisch (licorice) in Xinyuan, Gongliu, and Tekesi of Xinjiang Province, China, and identified based on their 16S rRNA gene sequences. The endophytes were highly diverse, including 20 genera and 35 species. The number of distinct bacterial genera obtained from root tissues was higher (n?=?14) compared to stem (n?=?9) and leaf (n?=?6) tissue. Geographically, the diversity of culturable endophytic genera was higher at the Tekesi (n?=?14) and Xinyuan (n?=?12) sites than the Gongliu site (n?=?4), reflecting the extremely low organic carbon content, high salinity, and low nutrient status of Gongliu soils. The endophytic bacteria exhibited a number of plant growth-promoting activities ex situ, including diazotrophy, phosphate and potassium solubilization, siderophore production, auxin synthesis, and production of hydrolytic enzymes. Twelve endophytes were selected based on their ex situ plant growth-promoting activities for growth chamber assays to test for their ability to promote growth of G. uralensis F. and Triticum aestivum (wheat) plants. Several strains belonging to the genera Bacillus (n?=?6) and Achromobacter (n?=?1) stimulated total biomass production in both G. uralensis and T. aestivum under low-nutrient conditions. This work is the first report on the isolation and characterization of endophytes associated with G. uralensis F. in arid lands. The results demonstrate the broad diversity of endophytes associated with wild licorice and suggest that some Bacillus strains may be promising candidates for biofertilizers to promote enhanced survival and growth of licorice and other valuable crops in arid environments. 相似文献
116.
Fabienne Nackers Yolanda Kathrin Mueller Niven Salih Mousab Siddig Elhag Mobarak Elnour Elbadawi Omer Hammam Ann Mumina Atia Abdalla Atia Jean-Fran?ois Etard Koert Ritmeijer Fran?ois Chappuis 《PLoS neglected tropical diseases》2015,9(11)
Background
Improving knowledge on local determinants of visceral leishmaniasis (VL) is crucial to guide the development of relevant control strategies. This study aimed to identify individual and household level determinants of primary VL in 24 highly endemic villages of Tabarak Allah hospital’s catchment area, Gedaref State, Sudan.Methods
From September 2012 to July 2013, in an unmatched case-control design, 198 patients with primary VL were compared to 801 controls free of VL symptoms and with a negative VL rapid test. Using random spatial sampling, controls were selected with a distribution of age, sex and village of residence proportionate to the distribution of the target population. Data were collected using a structured questionnaire.Results
Children and men were at higher risk of VL. Reporting VL patient(s) in the household in the previous year was the strongest VL risk factor. In a multivariate analysis, VL risk increased with household size, sleep location (outside the yard, not in the farm), evening outdoor activities in the rainy season (playing, watching TV, radio listening), use of ground nut oil as animal repellent and of smoke of Acacia seyal as indoor repellent, presence of dogs in the yard at night, Acacia nilotica in the yard’s immediate surroundings and of a forest at eye range. VL risk appeared to decrease with the use of drinking water sources other than the village water tank, a buffer distance from the adjacent house yard, and with the presence of animals other than dogs in the yard at night. In contrast with previous studies, housing factors, mosquito-net use, black cotton soil, ethnicity, socioeconomic index, presence of Balanites aegyptica and Azadirachta indica in the yard were not independent VL determinants.Discussion and conclusion
Although these results do not provide evidence of causality, they provide useful suggestions for guiding further intervention studies on VL preventive measures. 相似文献117.
NO Agbenin AM Emechebe PS Marley 《Archives Of Phytopathology And Plant Protection》2013,46(4):319-326
Fusarium wilt and root-knot are important diseases of tomato. The use of chemical is becoming less appealing because of the health implications. Also, the chemicals required are often not within the reach of farmers in most of the developing part of the world. This research is aimed at finding an alternative mode of control. Tomato variety Roma VF inoculated with Meloidogyne and Fusarium were treated with 2 g/kg soil neem seed powder in the screenhouse and 2 Mg ha ? 1 in the field. An untreated and Furadan treated plot in the field served as control. Neem seed powder significantly reduced the disease severity of Fusarium and root-knot in both screenhouse and field. Results suggest the possible use of neem seed powder for control of the root-knot nematodes - Fusarium wilt disease complex. 相似文献
118.
Background
In the past years the Smith-Waterman sequence comparison algorithm has gained popularity due to improved implementations and rapidly increasing computing power. However, the quality and sensitivity of a database search is not only determined by the algorithm but also by the statistical significance testing for an alignment. The e-value is the most commonly used statistical validation method for sequence database searching. The CluSTr database and the Protein World database have been created using an alternative statistical significance test: a Z-score based on Monte-Carlo statistics. Several papers have described the superiority of the Z-score as compared to the e-value, using simulated data. We were interested if this could be validated when applied to existing, evolutionary related protein sequences. 相似文献119.
Abdalla A. Elbashir Nuha Fathi Ali Dsugi Tamador Omer Mohamoud Mohmed Hassan Y. Aboul‐Enein 《Luminescence》2014,29(1):1-7
Cyclodextrins (CDs) are a family of cyclic oligosaccharides composed of α‐(1,4)‐linked glucopyranose subunits. The most important feature of CDs is their ability to form inclusion complexes (host–guest complexes) with a very wide range of solid, liquid and gaseous compounds by a molecular complexation. During the last decade, a considerable number of research papers has been focused on the use of CDs to enhance fluorescence intensity of different analytes and to develop CD‐induced spectrofluorimetric method. In this review, the various spectrofluorimetric methods based on host–inclusion complex are presented. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
120.