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131.
Seymour DK Filiault DL Henry IM Monson-Miller J Ravi M Pang A Comai L Chan SW Maloof JN 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(11):4227-4232
Quantitative trait loci (QTL) mapping is a powerful tool for investigating the genetic basis of natural variation. QTL can be mapped using a number of different population designs, but recombinant inbred lines (RILs) are among the most effective. Unfortunately, homozygous RIL populations are time consuming to construct, typically requiring at least six generations of selfing starting from a heterozygous F(1). Haploid plants produced from an F(1) combine the two parental genomes and have only one allele at every locus. Converting these sterile haploids into fertile diploids (termed "doubled haploids," DHs) produces immortal homozygous lines in only two steps. Here we describe a unique technique for rapidly creating recombinant doubled haploid populations in Arabidopsis thaliana: centromere-mediated genome elimination. We generated a population of 238 doubled haploid lines that combine two parental genomes and genotyped them by reduced representation Illumina sequencing. The recombination rate and parental allele frequencies in our population are similar to those found in existing RIL sets. We phenotyped this population for traits related to flowering time and for petiole length and successfully mapped QTL controlling each trait. Our work demonstrates that doubled haploid populations offer a rapid, easy alternative to RILs for Arabidopsis genetic analysis. 相似文献
132.
Lieber SB Redberg RF Blumenthal RS Gandhi A Robb KJ Mora S 《The American journal of cardiology》2012,109(12):1754-1760
Increased physical activity (PA) is associated with improvement of cardiac risk factors and prevention of cardiovascular disease, yet many women remain sedentary. With rising Internet use, Web-based interventions provide an alternative to improve PA, but their effectiveness for change in PA and quality of life (QOL) in a real-world setting is unknown. Participants were United States women ≥18 years old who received 12 weekly PA modules and completed surveys on PA, QOL, and readiness for PA at registration (registration cohort, n = 3,796) or registration and 12 weeks (evaluation cohort, n = 892). QOL was assessed with a modified Short Form-36 with subscores for energy and well-being. Participants showed significant (p <0.001) favorable changes in PA (baseline, median 240 kcal/week, interquartile range 62 to 667; 12 weeks, 343 kcal/week, 131 to 828), stage of readiness for PA, and body mass index (baseline, 29.3 kg/m(2), 24.9 to 34.7; 12 weeks, 28.9 kg/m(2), 24.6 to 34.2). Significant improvements (p <0.0001) were also found in composite scores for energy and well-being. Compliance with PA guideline recommendations increased from 15.8% to 21.4%. Program weeks completed (p = 0.03), energy (p = 0.04), and well-being (p = 0.002) were significantly associated with achieving guideline compliance. In women reporting no PA at baseline (n = 88), program participation resulted in 54.6% achieving some PA and another 9.1% achieving total compliance with recommendations. In conclusion, in this national cohort of women, a 12-week Web-based intervention improved PA and QOL measurements, resulting in higher short-term PA guideline compliance and better QOL. Increasing use of this simple Web-based tool could improve PA and promote disease prevention. 相似文献
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135.
J Oral Pathol Med (2012) 41 : 500–504 Background: Atrophic glossitis (AG) is considered to be a marker of nutritional deficiency. In this study, we evaluated whether there was an intimate association of the deficiency of hemoglobin, iron, vitamin B12 or folic acid, high blood homocysteine level, and serum gastric parietal cell antibody (GPCA) positivity with AG. Methods: The blood hemoglobin, iron, vitamin B12, folic acid, and homocysteine concentrations and the serum GPCA level in 176 AG patients were measured and compared with the corresponding levels in 176 age‐ and sex‐matched healthy control subjects. Results: We found that 39 (22.2%), 47 (26.7%), 13 (7.4%), and 3 (1.7%) AG patients had deficiencies of Hb (men < 13 g/dl, women < 12 g/dl), iron (<60 μg/dl), vitamin B12 (<200 pg/ml), and folic acid (<4 ng/ml), respectively. Moreover, 38 (21.6%) AG patients had abnormally high blood homocysteine level, and 47 (26.7%) AG patients had serum GPCA positivity. AG patients had a significantly higher frequency of Hb, iron, or vitamin B12 deficiency, of abnormally elevated blood homocysteine level, or of serum GPCA positivity than healthy control subjects (all P‐values = 0.000). However, no significant difference in frequency of folic acid deficiency was found between AG patients and healthy control subjects. Conclusion: We conclude that there is a significant association of deficiency of hemoglobin, iron and vitamin B12, abnormally high blood homocysteine level, and serum GPCA positivity with AG. 相似文献
136.
Technological advances in telehealth systems are primarily focused on sensing and monitoring. However, these systems are limited in that they only rely on sensors and medical devices to obtain vital signs. New research and development are urgently needed to offer more effective and meaningful interactions between patients, medical professionals and other individuals around the patients. Social networking with Web 2.0 technologies and methods can meet these demands, and help to develop a more complete view of the patient. Also many people, including the elderly, may be resistant to change, which can reduce the efficacy of telehealth systems. Persuasive technology and mechanisms are urgently needed to counter this resistance and promote healthy lifestyles. In this paper, we propose the participatory and persuasive telehealth system as a solution for these two limitations. By integrating connected health solutions with social networking and adding persuasive influence, we increase the chances for effective interventions and behavior alterations. 相似文献
137.
Andy C. Dean Tara L. Victor Kyle B. Boone Ginger Arnold 《The Clinical neuropsychologist》2013,27(4):705-722
The relationship between IQ and nine effort indicators was examined in a sample of 189 neuropsychology clinic outpatients who were not in litigation or attempting to obtain disability. Participants with the lowest IQ (50–59) failed approximately 60% of the effort tests, while patients with an IQ of 60 to 69 failed 44% of effort indicators, and individuals with borderline IQ (70 to 79) exhibited a 17% failure rate. All patients with IQ < 70 failed at least one effort test. Cutoffs for the Warrington Recognition Memory Test (Words) and Finger Tapping maintained the highest specificities in low IQ samples. 相似文献
138.
Background and objectives
Warfarin-related nephropathy is reported to occur with an INR >3.0 as a result of glomerular bleeding. There is a lack of prospective studies examining the effect of supratherapeutic warfarin anticoagulation on haematuria and acute kidney injury (AKI). Older patients may be susceptible due to greater warfarin use, prevalence of kidney disease and comorbidities. The objective of this study was to determine the incidence and nature of haematuria and AKI in older patients on warfarin and to determine any association with high INR levels.Design, setting, participants and measurements
This was a prospective, observational study of 150 elderly patients receiving warfarin anticoagulation who were acutely hospitalised in a tertiary hospital. AKI was assessed using RIFLE criteria. Urinalysis was performed to quantify haematuria, characterise erythrocyte morphology and measure the albumin–creatinine ratio. Positive cases received follow-up at 4–6 weeks to determine resolution.Results
An INR >3.0 was found in 54 % of patients. Pre-admission antibiotic use increased the risk of excessive anticoagulation. The incidence of isolated AKI, isolated haematuria and both was 18.7, 13.3 and 12 %, respectively. Factors associated with a higher risk of haematuria were an INR >4.0, non-urinary infection, catheterisation and albuminuria. Most cases of AKI were mild, and there was no demonstrable correlation between the admission INR and AKI. Admission with heart failure was significantly associated with an increased risk of persistent kidney impairment at follow-up.Conclusions
Supratherapeutic warfarin anticoagulation was associated with an increased risk of haematuria, but not with AKI. The majority of cases of haematuria were transient. 相似文献139.
140.
Medial portal technique for single-bundle anatomical Anterior Cruciate Ligament (ACL) reconstruction
The aim of the paper is to describe the medial portal technique for anatomical single-bundle anterior cruciate ligament (ACL) reconstruction. Placement of an ACL graft within the anatomical femoral and tibial attachment sites is critical to the success and clinical outcome of ACL reconstruction. Non-anatomical ACL graft placement is the most common technical error leading to recurrent instability following ACL reconstruction. ACL reconstruction has commonly been performed using a transtibial tunnel technique in which the ACL femoral tunnel is drilled through a tibial tunnel positioned in the posterior half of the native ACL tibial attachment site. ACL reconstruction performed using a transtibial tunnel technique often results in a vertical ACL graft, which may fail to control the combined motions of anterior tibial translation and internal tibial rotation which occur during the pivot-shift phenomenon. The inability of a vertically oriented ACL graft to control these combined motions may result in the patient experiencing continued symptoms of instability due to the pivot-shift phenomenon. The medial portal technique in which the ACL femoral tunnel is drilled through an anteromedial or accessory anteromedial portal allows consistent anatomical ACL tunnel placement. This paper describes the advantages of the medial portal technique, indications for the technique, patient positioning, proper portal placement, anatomical femoral and tibial tunnel placement, graft tensioning and fixation. 相似文献