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71.
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Female Aedes aegypti are assumed to be primarily monandrous (i.e., mate only once in their lifetime), but true estimates of mating frequency have not been determined outside the laboratory. To assess polyandry in Ae. aegypti with first-generation progeny from wild mosquitoes, stable isotope semen-labeled males ((15)N or (13)C) were allowed to mate with unlabeled females in semifield enclosures (22.5 m(3)) in a dengue-endemic area in southern Mexico. On average, 14% of females were positive for both labels, indicating that they received semen from more than one male. Our results provide evidence of a small but potentially significant rate of multiple mating within a 48-hour period and provide an approach for future open-field studies of polyandry in this species. Polyandry has implications for understanding mosquito ecology, evolution, and reproductive behavior as well as genetic strategies for mosquito control.  相似文献   
73.
Most Aedes aegypti dispersal studies have focused on females because of their central role in dengue virus transmission. Only a few mark-release-recapture (MRR) studies provided insights into male Ae. aegypti dispersal. To fill this knowledge gap, we conducted five male Ae. aegypti MRR experiments in a coastal village in southern Mexico. Small and large male cohorts were marked with fluorescent dusts, released outside buildings, and recaptures were carried out by using backpack aspirators. Recapture rates ranged between 0.35% and 6.55% and median distance traveled was 12-166 meters. A statistically significant difference in median distance traveled with large males dispersing farther than small ones was detected only in one experiment (MRR5: U = 3.5, P < 0.01). Male dispersal data will be useful for constructing and estimating parameter values and validating models that will be used to plan the most effective release strategies for genetically modified male Ae. aegypti.  相似文献   
74.
There are no quantitative standards for the volumetric measurements of the orbital cavity after Le Fort III advancement. Computed tomography (CT) scan images have given the opportunity to compare with accuracy the real anatomic changes and potentially the functional improvements that resulted after a surgical treatment.Three-dimensional CT scan images processed by DICOM files in Dolphin 3D Software were used to assess orbital volume and surface in 12 subjects affected by craniofacial syndromic malformations treated with Le Fort III advancement. The preoperative (T0) and postoperative (T1: 6 months after surgery) three-dimensional craniofacial CT scans of the subjects were collected and retrospectively analyzed. Image segmentation of the anatomic orbital cavity and the three-dimensional graphic rendering were done by using the Dolphin Imaging Plus 11.0 software.The orbital volume was increased after surgery, with statistical significance, from 22,267 to 22,706.3 mm(3) in the right eye and from 26,511 mm(3) to 26,256.4 mm(3) in the left eye. The surface of both bony orbits had an expansion, which is statistically significant. In conclusion, this study showed that the orbital advancement in white subjects after Le Fort III advancement was significant and produced a significant augmentation of the orbital volume and surface area with correction of the ocular bulb proptosis.  相似文献   
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Background: The role of speckle tracking in the assessment of right atrial (RA) deformation dynamics has not been established yet. The reference ranges of RA longitudinal strain indices were measured by speckle tracking in a population of normal subjects. Methods: In 84 healthy individuals, peak atrial longitudinal strain (PALS), peak atrial contraction strain (PACS), and time to peak longitudinal strain (TPLS) were measured using a six‐segment model for the RA. Strain rate (SR) was also measured starting from the QRS‐wave onset, peak positive (x‐wave), first peak negative (y‐wave), and second negative peak (z‐wave). The time from the QRS onset was measured to each wave peak. Results: Adequate tracking quality was achieved in 64% of segments analyzed. Inter‐ and intraobserver variability coefficients of measurements ranged between 6% and 11%. Global PALS was 49 ± 13%, global TPLS was 363 ± 59 msec, x‐wave was 2.12 ± 0.58 sec?1, y‐wave was ?1.91 ± 0.63 sec?1, and z‐wave was ?2.18 ± 0.78 sec?1. Conclusion: Speckle tracking is a feasible technique for the assessment of longitudinal myocardial RA deformation. Reference ranges of strain indices were reported. (Echocardiography 2012;29:147‐152)  相似文献   
77.
Recent advances in social neuroscience research have unveiled the neurophysiological correlates of race and intergroup processing. However, little is known about the neural mechanisms underlying intergroup empathy. Combining event‐related fMRI with measurements of pupil dilation as an index of autonomic reactivity, we explored how race and group membership affect empathy‐related responses. White and Black subjects were presented with video clips depicting white, black, and unfamiliar violet‐skinned hands being either painfully penetrated by a syringe or being touched by a Q‐tip. Both hemodynamic activity within areas known to be involved in the processing of first and third‐person emotional experiences of pain, i.e., bilateral anterior insula, and autonomic reactivity were greater for the pain experienced by own‐race compared to that of other‐race and violet models. Interestingly, greater implicit racial bias predicted increased activity within the left anterior insula during the observation of own‐race pain relative to other‐race pain. Our findings highlight the close link between group‐based segregation and empathic processing. Moreover, they demonstrate the relative influence of culturally acquired implicit attitudes and perceived similarity/familiarity with the target in shaping emotional responses to others' physical pain. Hum Brain Mapp 34:3168–3181, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
78.
Background/Aims: Elevated thyroid-stimulating hormone (TSH) concentrations in association with normal/slightly elevated free triiodothyronine (fT(3)) and/or free thyroxine (fT(4)) have been consistently found in obese children. To examine relationships between adiposity, insulin sensitivity, and TSH, fT(3) and fT(4). Methods: 240 overweight/obese prepubertal children were studied. Fasting TSH, fT(3), fT(4), glucose, insulin, C-peptide, lipids, leptin and adiponectin were evaluated. Insulin sensitivity and resistance were estimated [quantitative insulin check index (QUICKI), insulin sensitivity index (ISI), and hepatic insulin resistance index]. Body fat was measured by dual-energy X-ray absorptiometry. The central obesity index was calculated as the ratio of fat tissue in the trunk region to fat tissue in the leg region. Results: The multiple regression analysis with age, gender and measures of fatness as covariates showed that QUICKI was the only significant negative predictor of TSH and central obesity index the strongest positive predictor of fT(3), in association with either age or hepatic insulin resistance index, and that the only positive determinant of fT(4) was hepatic insulin resistance index. Conclusions: Reduced insulin sensitivity is associated with augmented TSH and fT(4), while progressive central fat accumulation is strictly related to a parallel increase in fT(3) levels, independently from total body fat. Further studies are needed to understand mechanisms linking thyroid function to insulin sensitivity and body composition in obese children.  相似文献   
79.
This is a retrospective, non-comparative study of 212 consecutive patients who underwent Total Hip Arthroplasty with an uncemented hydroxyapatite (HA) coated stem system from November 1997 to March 2000. The objective of the study was to analyze the performance of the implant at a minimum of 10 years in older patients (mean age 79.6 years). The Kaplan-Meier survivorship of the femoral stem at 10 years was 100%, and 97.5% for the whole prosthesis. The mean Merle d'Aubigné clinical score improved from 4.4 ± 2.1 points pre-operatively to 13.39 ± 3.77 points at final follow-up (p < 0.05), and the mean VAS score for thigh pain was 1.25. The radiographic analysis showed that there were no significant radiolucent lines or osteolysis compromising the fixation of the implant.  相似文献   
80.
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