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991.
Susanna B. Ali Marvin Reid Raphael Fraser Michelle MooSang Amza Ali 《British journal of haematology》2010,151(3):265-272
Although there is some evidence that epilepsy is more common in Sickle Cell Disease (SCD), we sought to establish the incidence rates, risk factors for and specific types of seizures in a SCD cohort followed from birth, and how seizure occurrence affects morbidity and mortality . We examined all records of persons in the Jamaica cohort Study of Sickle Cell Disease (JSSCD) clinically identified as having experienced a seizure during their lifetime. At first presentation, seizures were classified as Febrile Convulsion, Acute Symptomatic Seizure or Single Unprovoked Seizure. The seizure classification was revised to include Epilepsy if seizures recurred. Thirty‐eight persons in the JSSCD (N = 543) were identified with seizures. The 5‐year cumulative incidence of febrile convulsions was 2·2%. The incidence rate of epilepsy (all genotypes) was 100/100 000 person‐years, 139/100 000 for the SS genotype. Despite limited availability of diagnostic investigations, clinical seizures were associated with increased all‐cause mortality. Male gender (Odds Ratio [OR]: 4·0[95% confidence interval [CI]; 1·03–20·0]) and dactylitis in childhood (OR: 17·4 [95% CI; 4·82–62·85]) were associated with increased risk of developing epilepsy. Epilepsy in persons with SCD is 2–3 times more common than in non‐sickle populations and is associated with increased all‐cause mortality in all sickle cell genotypes. 相似文献
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996.
Holly J. Puglis Michelle D. Boone 《Archives of environmental contamination and toxicology》2011,60(1):145-155
Commercial formulations of pesticides contain both active and other ingredients. In some instances, the other ingredients
have detrimental effects on nontarget species. Other factors such as UV radiation and predator cues have been shown to modify
the toxicity of pesticides. In a laboratory study we compared the effects of technical-grade active ingredients to commercial
formulations of seven common pesticides in the presence or absence of UV radiation on the survival of Rana clamitans (green frog) tadpoles over 96 h. We found a significant difference in the survival of tadpoles in technical-grade active
ingredients versus commercial formulations in all of the pesticides tested. We also found that either the presence or the
absence of UV radiation affected the survival of tadpoles in five of the seven pesticides tested. These results suggest that
there is a need to test the effects of both active ingredients and commercial formulations of pesticides and, also, to include
relevant abiotic factors like UV radiation treatments in the testing of pesticides because they can have a dramatic impact
on the toxicity of some chemicals. 相似文献
997.
Jose A. Rodríguez Miguel A. Lopez Michelle C. Thayer Yunzhe Zhao Michael Oberholzer Donald D. Chang Neville K. Kisalu Manuel L. Penichet Gustavo Helguera Robijn Bruinsma Kent L. Hill Jianwei Miao 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(46):19322-19327
Trypanosoma brucei, a parasitic protist with a single flagellum, is the causative agent of African sleeping sickness. Propulsion of T. brucei was long believed to be by a drill-like, helical motion. Using millisecond differential interference-contrast microscopy and analyzing image sequences of cultured procyclic-form and bloodstream-form parasites, as well as bloodstream-form cells in infected mouse blood, we find that, instead, motility of T. brucei is by the propagation of kinks, separating left-handed and right-handed helical waves. Kink-driven motility, previously encountered in prokaryotes, permits T. brucei a helical propagation mechanism while avoiding the large viscous drag associated with a net rotation of the broad end of its tapering body. Our study demonstrates that millisecond differential interference-contrast microscopy can be a useful tool for uncovering important short-time features of microorganism locomotion. 相似文献
998.
Carl V. Tyler Stephen J. Zyzanski Michelle Berkley Vanessa Panaite 《Journal of the National Medical Association》2009,101(6):588-592
IntroductionInadequate calcium intake is more common among women belonging to racial and ethnic minorities. This study examined the patterns and characteristics associated with calcium supplement use or nonuse among African American women, and the potential impact of physician recommendation on calcium supplementation.MethodsAfrican American women aged 19 to 65, attending community outreach activities sponsored by a multispecialty academic medical center in northeastern Ohio, completed a calcium supplement survey. Survey items included demographic and bone health–related information, and rationale for calcium supplement use or nonuse.ResultsOf 160 respondents, 14% of women regularly took calcium supplements, 16% were former users, and 70% never used calcium supplements. Characteristics associated with calcium use status included age, multivitamin use, and marital status. Few African American women recall discussions with their doctors about calcium intake. Most who formerly took calcium supplements and most who had never taken them were willing to do so if recommended by their physician.DiscussionCalcium supplement use among African American women in this study was low. However, many of the barriers to calcium supplement use by African American women appear remediable through brief calcium intake counseling by their physician. 相似文献
999.
Aurélie Spagnul Céline Bouvier-Capely Guillaume Phan Géraldine Landon Christine Tessier David Suhard François Rebière Michelle Agarande Elias Fattal 《European journal of pharmaceutics and biopharmaceutics》2011,79(2):258-267
Cutaneous contamination by radionuclides is a major concern in the nuclear industry. In case of skin exposure to uranium, no efficient emergency treatment is available to remove the actinide from the skin. For this purpose, we developed a nanoemulsion containing calixarene molecules displaying good chelating properties towards uranium. In this paper, we describe the ability of this formulation to trap uranium and limit its transfer from the cutaneous contaminated site into the blood. Uranium percutaneous diffusion kinetics was assessed with Franz cells over 24 h through intact and excoriated pig ear skin biopsies, after or without application of the nanoemulsion. Uranium distribution in the skin layers was analysed by SIMS microscopy. The results showed that prompt application of the calixarene nanoemulsion allows a 94% and 98% reduction of the amount of uranium diffused respectively through intact and excoriated skin. The formulation is still efficient in case of delayed application up to 30 minutes since the 24 h-uranium transfer through excoriated skin is reduced by 71%. Besides, no accumulation of uranium or uranium-calixarene chelate was observed in the different skin layers. In conclusion, this study demonstrated the efficiency of the calixarene nanoemulsion, which can be regarded as a promising treatment for uranium cutaneous contamination. 相似文献
1000.
Adam Danquah Kate Limb Melanie Chapman Carrie Burke Andrea Flood Sarah Gore Kara Greenwood Kelsey Healey William Kerr Reid Jan Kilroy Huma Lacey Caroline Malone Michelle Perkin Dougal Julian Hare 《Journal of Applied Research in Intellectual Disabilities》2009,22(4):395-399
Background Self‐injurious behaviour (SIB) is among the most serious problems faced by intellectual disability services. It is very difficult to treat and can become a chronic problem. Method Information on a number of variables was collected through a survey of service‐users identified as displaying SIBs. Clinical opinion and a literature review guided the selection of potential predictors of continued SIB. Univariate statistical analyses were used to investigate associations between continued SIB and each of the variables identified. Variables shown to have a significant association with continued SIB were subjected to a multivariate analysis to isolate those variables that still predicted continued SIB once the influence of the others had been accounted for. Results Two factors, self‐biting and verbal ability, were found to independently predict continued SIB. Conclusion The results have implications for intellectual disability services, in terms of the importance of multidisciplinary team working, training and guidelines for problem management. 相似文献