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51.
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Manoukis NC Powell JR Touré MB Sacko A Edillo FE Coulibaly MB Traoré SF Taylor CE Besansky NJ 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(8):2940-2945
The role of chromosomal inversions in speciation has long been of interest to evolutionists. Recent quantitative modeling has stimulated reconsideration of previous conceptual models for chromosomal speciation. Anopheles gambiae, the most important vector of human malaria, carries abundant chromosomal inversion polymorphism nonrandomly associated with ecotypes that mate assortatively. Here, we consider the potential role of paracentric inversions in promoting speciation in A. gambiae via "ecotypification," a term that refers to differentiation arising from local adaptation. In particular, we focus on the Bamako form, an ecotype characterized by low inversion polymorphism and fixation of an inversion, 2Rj, that is very rare or absent in all other forms of A. gambiae. The Bamako form has a restricted distribution by the upper Niger River and its tributaries that is associated with a distinctive type of larval habitat, laterite rock pools, hypothesized to be its optimal breeding site. We first present computer simulations to investigate whether the population dynamics of A. gambiae are consistent with chromosomal speciation by ecotypification. The models are parameterized using field observations on the various forms of A. gambiae that exist in Mali, West Africa. We then report on the distribution of larvae of this species collected from rock pools and more characteristic breeding sites nearby. Both the simulations and field observations support the thesis that speciation by ecotypification is occurring, or has occurred, prompting consideration of Bamako as an independent species. 相似文献
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Sawitzke AD Shi H Finco MF Dunlop DD Bingham CO Harris CL Singer NG Bradley JD Silver D Jackson CG Lane NE Oddis CV Wolfe F Lisse J Furst DE Reda DJ Moskowitz RW Williams HJ Clegg DO 《Arthritis and rheumatism》2008,58(10):3183-3191
OBJECTIVE: Osteoarthritis (OA) of the knee causes significant morbidity and current medical treatment is limited to symptom relief, while therapies able to slow structural damage remain elusive. This study was undertaken to evaluate the effect of glucosamine and chondroitin sulfate (CS), alone or in combination, as well as celecoxib and placebo on progressive loss of joint space width (JSW) in patients with knee OA. METHODS: A 24-month, double-blind, placebo-controlled study, conducted at 9 sites in the United States as part of the Glucosamine/Chondroitin Arthritis Intervention Trial (GAIT), enrolled 572 patients with knee OA who satisfied radiographic criteria (Kellgren/Lawrence [K/L] grade 2 or grade 3 changes and JSW of at least 2 mm at baseline). Patients with primarily lateral compartment narrowing at any time point were excluded. Patients who had been randomized to 1 of the 5 groups in the GAIT continued to receive glucosamine 500 mg 3 times daily, CS 400 mg 3 times daily, the combination of glucosamine and CS, celecoxib 200 mg daily, or placebo over 24 months. The minimum medial tibiofemoral JSW was measured at baseline, 12 months, and 24 months. The primary outcome measure was the mean change in JSW from baseline. RESULTS: The mean JSW loss at 2 years in knees with OA in the placebo group, adjusted for design and clinical factors, was 0.166 mm. No statistically significant difference in mean JSW loss was observed in any treatment group compared with the placebo group. Treatment effects on K/L grade 2 knees, but not on K/L grade 3 knees, showed a trend toward improvement relative to the placebo group. The power of the study was diminished by the limited sample size, variance of JSW measurement, and a smaller than expected loss in JSW. CONCLUSION: At 2 years, no treatment achieved a predefined threshold of clinically important difference in JSW loss as compared with placebo. However, knees with K/L grade 2 radiographic OA appeared to have the greatest potential for modification by these treatments. 相似文献
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Multifactorial inheritance hypothesis for the etiology of congenital heart diseases. The genetic-environmental interaction 总被引:11,自引:0,他引:11
J J Nora 《Circulation》1968,38(3):604-617
57.
Saed H Zyoud Dala N Daraghmeh Diana O Mezyed Razan L Khdeir Mayas N Sawafta Nora A Ayaseh Ghada H Tabeeb Waleed M Sweileh Rahmat Awang Samah W Al-Jabi 《Lancet》2018
Background
Haemodialysis is a life-saving but burdensome therapy for patients with end-stage renal disease, which can substantially impair health-related quality of life (HRQOL) and outcomes. The aim of this study was to determine the patterns of HRQOL and to identify the risk factors for reduced HRQOL in Palestinian patients receiving treatment by haemodialysis.Methods
This cross-sectional study was done between June 15, 2014, and Jan 15, 2015, using the EuroQOL-5 Dimensions instrument (EQ-5D-5L) for the assessment of HRQOL. We approached patients with end-stage renal disease undergoing haemodialysis at inpatient hospitals from ten different settings at a national level. The study protocol was approved by the Ethics Committee of An-Najah National University. Informed verbal consent was obtained from each participant before the start of the interview. Multiple linear regression was used to estimate which variables were significantly associated with reduced HRQOL.Findings
267 (96%) of 277 eligible patients consented to participate. 139 (52%) participants were men, and the mean age was 53·3 years (SD 16·2). 177 (66%) patients had been treated by haemodialysis for less than 4 years. The reported HRQOL, as measured by mean EQ-5D-5L index value, was 0·37 (SD 0·44). We found a moderate positive correlation between the EuroQol-visual analogue scales and the EQ-5D-5L index value (r=0·44; p<0·0001). The results of a multiple linear regression showed a significant association between HRQOL and age (p=0·0011), female sex (p=0·0167), education level (p=0·0057), number of chronic medications (p=0·0493), and number of comorbid diseases (p=0·0001).Interpretation
Our results provide insight into a number of associations between patient variables such as demographics, clinical factors, and their HRQOL. These findings should help raise health-care providers' awareness and improve the quality of life for patients receiving treatment by haemodialysis, especially those who have no formal education, are elderly, are female, are from refugee camps, or have multiple comorbid diseases or chronic medications.Funding
None. 相似文献58.
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María Elena Contreras Campos Nora Rodríguez‐Cervantes Sandra Reza‐López Marina Ávila‐Esparza Dora Virginia Chávez‐Corral Margarita Levario‐Carrillo 《Maternal & child nutrition》2015,11(2):164-172
Teenage pregnancy has been associated with adverse effects for the mother and the newborn (NB). In order to compare body composition (BC) between adolescents (Ad) and mature women (MW) during pregnancy and to determine the difference in birthweight and perinatal morbidity, pregnant Ad (n = 40) and MW (n = 227) were studied. BC changes between the second and third trimesters were determined by multifrequency bioelectrical impedance analysis, and birthweight and NB morbidity were evaluated. During the second and third trimesters of the pregnancy, fat mass was lower in the Ad group [16 kg (13–19)] than in the MW group [22 kg (17–27)] (P < 0.01; median and quartiles 1–3). Fat‐free mass increased by 3.09 kg (2.29–4.20) and 2.20 kg (1.0–3.59) (P ≤ 0.01), and total body water increased by 2.77 L (0.84–4.49) vs. 2.04 L (0.55–3.89) (P = 0.36), in the Ad and MW groups, respectively (median and quartiles 1–3). Birthweight was not significantly different between NBs of Ad (3223 ± 399 g) and NBs of MW (3312 ± 427 g, P = 0.22). The youngest Ad (<18 year old, n = 8) had NB with lower birthweight than MW (3031 ± 503 g, P = 0.06). NBs of Ad mothers showed a non‐significant trend towards a higher rate of morbidity relative to the NBs of MW. In conclusion, the BC of Ad differs from that of MW during pregnancy. In addition, the NB infants of Ad mothers tended to have a lower birthweight than those from MW, a result that suggests that the Ad should be in strict prenatal control. 相似文献
60.