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21.
We hypothesized that control processes, as measured using electrophysiological (EEG) variables, influence the rate of learning of complex tasks. Specifically, we measured alpha power, event‐related spectral perturbations (ERSPs), and event‐related brain potentials during early training of the Space Fortress task, and correlated these measures with subsequent learning rate and performance in transfer tasks. Once initial score was partialled out, the best predictors were frontal alpha power and alpha and delta ERSPs, but not P300. By combining these predictors, we could explain about 50% of the learning rate variance and 10%–20% of the variance in transfer to other tasks using only pretraining EEG measures. Thus, control processes, as indexed by alpha and delta EEG oscillations, can predict learning and skill improvements. The results are of potential use to optimize training regimes.  相似文献   
22.
ABSTRACT

Urban environments marked by violence create fear that can have real impacts on the urban poor, particularly women and girls. Any efforts to tackle poverty and promote health must address the impacts to their access to livelihoods and education, healthcare, markets, and social support that underlie wellbeing. This study aimed to elucidate specific impacts that violence and fear have on the very poor in rapidly growing cities and the coping strategies employed. This multi-country qualitative study was conducted in Dhaka, Bangladesh, Port-au-Prince, Haiti; and Addis Ababa, Ethiopia. Participants in all three cities employed similar tactics to avoid violence. People adjusted how, when, and where they travel and how they interact with people who threaten them. These coping strategies led participants to spend more money on goods and to restrict access to livelihood opportunities, education, healthcare, and social activities. Women are impacted more than men in all spheres and city specific differences are highlighted. Residents of urban slums, particularly women, in these three cities cope with urban violence in many ways, suffering consequences in a range of categories – leading to significant impacts to their own health and well-being and their families.  相似文献   
23.
Cerebrovascular support is crucial for healthy cognitive and brain aging. Arterial stiffening is a cause of reduced brain blood flow, a predictor of cognitive decline, and a risk factor for cerebrovascular accidents and Alzheimer's disease. Arterial health is influenced by lifestyle factors, such as cardiorespiratory fitness (CRF). We investigated new noninvasive optical measures of cerebrovascular health, which provide estimates of arterial pulse parameters (pulse pressure, transit time, and compliance/elasticity) within specific cerebral arteries and cortical regions, and low‐resolution maps of large superficial cerebral arteries. We studied naturally occurring variability in these parameters in adults (aged 55–87), and found that these indices of cerebrovascular health are negatively correlated with age and positively with CRF and gray and white matter volumes. Further, regional pulse transit time predicts specific neuropsychological performance.  相似文献   
24.
Endosalpingosis, a condition characterized by ectopic oviduct epithelium, is diagnosed histologically by the appearance of benign ciliated and nonciliated columnar cells in an abnormal location. Endosalpingosis is typically without symptoms. Our unusual case report shows symptomatic endosalpingosis first seen with chronic pelvic pain. Various aspects of this disease will also be discussed.  相似文献   
25.
Experimental glaucoma was produced in one eye of five cynomolgus monkeys with the argon laser delivering 100-200 50-mu spots at 1200-1500 mW power and 0.5 sec to 360 degrees of the mid-trabecular meshwork. Monocular electroretinograms (ERGs) were recorded prior to and 2, 3, and 4 mo following the laser treatment. In the laser-treated (glaucoma) eyes, normal flash ERGs were observed using 1-Hz stimulation; however, pattern ERGs (PERGs) elicited using steady-state counterphase modulation of a 0.51 cpd square wave grating showed statistically significant reductions of amplitude. Only small reductions of PERG amplitude were seen with a 1.25 cpd grating. In three animals, abnormalities of the PERG occurred prior to clinically significant cupping of the optic nervehead. Moreover, reductions of PERG amplitude were progressive and associated with the magnitude of cupping of the optic nervehead and elevation of intraocular pressure. PERG amplitude did not change following acute reductions in intraocular pressure in the glaucoma eyes. Several control experiments were conducted to insure that results were not due to alterations in pupil size, refractive state, or accommodation in the glaucoma eyes. The authors believe they now have a monkey model for the electrophysiologic study of glaucoma.  相似文献   
26.
A patient with PCO and primary infertility had undergone numerous failed attempts of ovulation induction. She then was treated with GnRHa leuprolide 500 micrograms subcutaneously daily for 4 weeks, later combined with hMG 225 IU IM daily for 8 days and hCG 5000 IU IM. Six oocytes were retrieved for IVF, four fertilized and two were replaced. Twin pregnancy was established and delivered at term. Hyperstimulation syndrome was managed conservatively.  相似文献   
27.
Paternal mitochondrial DNA is normally eliminated from mammalian embryos. We have shown the presence of paternal mtDNA at the blastocyst stage in some abnormal human embryos.  相似文献   
28.
Characteristics of follicular development and hormonal patterns were evaluated in 17 women with minimal endometriosis and 11 with unexplained infertility. The controls were 7 women with male factor infertility and 8 who conceived during an investigational cycle. Women with minimal endometriosis had more and smaller follicles at luteinizing hormone (LH) surge, lower preovulatory estradiol (E2), and lower E2 at LH surge. Women with unexplained infertility had lower LH surges and a trend to a shorter follicular phase. Occult ovulatory dysfunction and may contribute to infertility in women with minimal endometriosis or unexplained infertility.  相似文献   
29.
Sonographic diagnosis of hypertrophic pyloric stenosis   总被引:8,自引:0,他引:8  
In many pediatric centers, sonography has become the primary imaging method for the diagnosis of hypertrophic pyloric stenosis, but investigators have disagreed about which dimension of the gastric outlet is most useful and accurate. We analyzed 326 consecutive sonograms in 319 infants who presented with vomiting in order to further evaluate the sonographic criteria for the diagnosis of hypertrophic pyloric stenosis. Four observers retrospectively measured three parameters: (1) the thickness of the muscle in the wall of the gastric outlet, (2) the length of that muscle, and (3) the length of the pyloric channel. In the patients with hypertrophic pyloric stenosis, muscle thickness was 4.8 +/- 0.6 mm, muscle length was 2.1 +/- 0.3 cm, and channel length was 1.8 +/- 0.3 cm. In the patients without hypertrophic pyloric stenosis, muscle thickness was 1.8 +/- 0.4 mm, muscle length was 1.3 +/- 0.3 cm, and channel length was 1.1 +/- 0.3 cm. The mean measurement for each parameter was significantly larger in patients who had hypertrophic pyloric stenosis than in those who did not (p less than .01). However, histograms of the three parameters show significant overlap in the measurements of muscle length and channel length between the patients with and those without hypertrophic pyloric stenosis. The thickness of the muscle is the most discriminating and accurate criterion for hypertrophic pyloric stenosis.  相似文献   
30.
The authors successfully used magnetoencephalography and MR data to localize the sensorimotor cortex in two patients prior to neurosurgery; preoperative localization influenced surgical management.  相似文献   
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