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Procedural learning is subject to consolidation processes believed to depend on the modulation of functional connections involved in representing the acquired skill. While sleep provides the most commonly studied framework for such consolidation processes, posttraining modulation of oscillatory brain activity may also impact on plasticity processes. Under the hypothesis that consolidation of motor learning is associated with theta band activity, we used EEG neurofeedback (NFB) to enable participants to selectively increase either theta or beta power in their EEG spectra following the acquisition phase of motor sequence learning. We tested performance on a motor task before and after training, right after the NFB session to assess immediate NFB effects, 1 day after NFB to assess interaction between NFB effects and overnight sleep‐dependent stabilization, and 1 week after the initial session, to assess the effects of NFB on long‐term stabilization of motor training. We also explored the extent of the influence of single‐electrode NFB on EEG recorded across the scalp. Results revealed a significantly greater improvement in performance immediately after NFB in the theta group than in the beta group. This effect continued for testing up to 1 week following training. Across participants, post‐NFB improvement correlated positively with theta/beta ratio change achieved during NFB. Additionally, NFB was found to cause widespread band‐power modulation beyond the electrode used for feedback. Thus, upregulating postlearning theta power may yield contributions to the immediate performance and subsequent consolidation of an acquired motor skill.  相似文献   
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Current therapy of childhood cancer makes long-term survival a realistic outcome for most patients. However, some treatment regimens entail a significant risk of infertility. No established method for preservation of female fertility is currently available. Ovarian cryopreservation is an experimental technology that is being offered with increasing frequency to women undergoing cancer therapy. It has not yet been reported in children and adolescent girls. The aim of this review is to stimulate discussion on the possibility of performing ovarian cryopreservation in pre-menarcheal girls in advance of therapies that may induce ovarian failure. We present a multi-disciplinary discussion of the risks and benefits associated with the procedure and propose guidelines for its implementation. We propose that all girls about to receive treatment that has a high risk for infertility be offered consultation about the possibility of ovarian cryopreservation.  相似文献   
55.
Melatonin is secreted during the night in adults but not in infants. It has a hypnotic effect as well as a relaxing effect on the smooth muscle of the gastrointestinal tract. It is plausible that breast milk, which consists of melatonin, may have an effect on improving infants' sleep and reducing infantile colic. Our first goal was to assess the differences in the prevalence and severity of infantile colic and nocturnal sleep between breast-fed infants and supplement-fed infants. The second was to characterize the profile of melatonin secretion in human breast milk compared to artificial formulas. Ninety-four mothers of healthy 2 to 4-month-old infants filled a questionnaire regarding irritability/potential infantile colic and sleep characteristics. For the second part, we measured melatonin levels in breast milk of five women every 2 h during 24 h and in three samples of commonly used artificial formulas. Exclusively breast-fed infants had a significantly lower incidence of colic attacks (p = 0.04), lower severity of irritability attacks (p = 0.03), and a trend for longer nocturnal sleep duration (p = 0.06). Melatonin in human milk showed a clear circadian curve and was unmeasurable in all artificial milks. Conclusions. Exclusive breastfeeding is associated with reduced irritability/colic and a tendency toward longer nocturnal sleep. Breast milk (nocturnal) consists of substantial melatonin levels, whereas artificial formulas do not. We speculate that melatonin which is supplied to the infant via breast milk plays a role in improving sleep and reducing colic in breast-fed infants compared to formula-fed ones.  相似文献   
56.
Research questionIs the interval length between an early pregnancy loss and the following treatment cycle a predictor for achieving clinical pregnancy among IVF patients?DesignThis retrospective cohort study of 257 women who reinitiated treatment after first-trimester IVF pregnancy loss was conducted at a tertiary, university-affiliated medical centre between 1 January 2014 to 1 January 2018. Women aged 18–40 years, with normal uterine cavity, who experienced first-trimester pregnancy loss at less than 14 weeks after IVF, were included. Miscarriages were classified as spontaneous, biochemical, medical or surgical.ResultsAmong 257 women, interval to subsequent IVF treatment was not associated with achieving pregnancy. Patients after biochemical pregnancy (72.7 ± 56.4, median 60 days) or spontaneous miscarriage (97.7 ± 93.1, median 66 days) had shorter intervals to next cycle, compared with medical (111.9 ± 103.2, median 65 days) or surgical (123.4 ± 111.1, median 84 days) (Kaplan–Meier, P = 0.03) miscarriages.Logistic regression analysis showed that the chance of subsequent pregnancy was affected by the number of embryos transferred (P = 0.009) and the type of miscarriage. Medical (P = 0.005) and surgical (P = 0.017) miscarriages were related to lower likelihood of pregnancy compared with biochemical pregnancy (reference group).When pregnancy was achieved in the first post-miscarriage cycle, the chance of live birth increased with shorter intervals (median 57.5 days), whereas second miscarriage was related to longer intervals (median 82.5 days) between miscarriage and subsequent IVF cycle (P = 0.03).ConclusionOn the basis of this cohort, IVF should not be postponed after pregnancy loss, as shorter intervals were associated with greater likelihood of live birth.  相似文献   
57.
Journal of Neurology - People with multiple sclerosis (pwMS) often suffer from gait impairments. These changes in gait have been well studied in laboratory and clinical settings. A thorough...  相似文献   
58.
This work investigates whether inhibition impairments influence the decision making process in pathological gamblers (PGs). The PG (N = 51) subjects performed the Iowa Gambling Task (IGT as the measure of the decision making process) and two tests of inhibition: the Stroop (interference inhibition), and the Go/NoGo (response inhibition), and were compared with demographically matched healthy subjects (N = 57). Performance in the IGT block 1 and block 2 did not differ between the groups, but the differences between the PGs and healthy controls began to be significant in block 3, block 4 and block 5. PGs learned the IGT task more slowly than the healthy controls and had non-optimal outcomes (more disadvantageous choices). Impaired IGT performance in PGs was not related to an inhibition ability measured by the Stroop (interference response time) and the Go/NoGo (number of commission errors) parameters. Further controlled studies with neuroimaging techniques may help to clarify the particular brain mechanisms underlying the impaired decision making process in PGs.  相似文献   
59.
Abstract

Purpose: To determine if head circumference (HC) is an independent factor influencing second stage duration stratified by parity and epidural use.

Materials and methods: A retrospective cohort analysis of all live, singleton, term (37–42 weeks) vaginal deliveries in one university affiliated medical center (2012–2014). Exclusion criteria included operative deliveries due to fetal distress, major fetal anomalies/chromosomal abnormalities or cases with missing anthropometric data. Maternal demographics, labor characteristics and neonatal anthropometrics including birth weight and HC were retrieved. Multivariate linear regression was utilized to evaluate the association between HC and second stage duration. Analysis was stratified into four groups by parity and epidural use.

Results: Of the 16 240 singleton vaginal deliveries during study period, 12 428 deliveries met inclusion criteria. Stratification by parity and epidural analgesia yielded four groups: 3337 (26.9%), 735 (5.9%), 5099 (41.0%) and 3257 (26.2%) deliveries – nullipara with/without epidural and multipara with/without epidural, respectively. In all groups, a large neonatal HC was significantly and independently associated with longer second stage duration: nullipara with epidural (beta 10.06, 95% CI 7.75–12.37), nullipara without epidural (beta 7.58, 95% CI 4.73–10.43), multipara with epidural (beta 4.64, 95%CI 3.47–5.8) and multipara without epidural (beta 1.35, 95% CI 0.76–1.94), p?<?.001 for all. Birth weight was not associated with second stage duration in any of the groups (p?>?.05).

Conclusion: Large neonatal HC is significantly associated with longer second stage duration.  相似文献   
60.
Kramer MR, Amital A, Fuks L, Shitrit D. Voriconazole and itraconazole in lung transplant recipients receiving tacrolimus (FK 506): efficacy and drug interaction.
Clin Transplant 2011: 25: E163–E167. © 2010 John Wiley & Sons A/S. Abstract: Background: The aim of this study was to compare the extent of interaction between tacrolimus and itraconazole vs. voriconazole. Patients and methods: This retrospective study included 60 lung transplant recipients who were treated with a tacrolimus‐based regimen; 40 received prophylactic itraconazole for the first six months following lung transplantation (LTX), and 20 were treated with voriconazole. All patients had at least 12 months of follow‐up. Tacrolimus levels and dosage requirements were compared during and after azole therapy. We assessed the rejection rate, fungal infection rate, and renal function during the study period. Results: The mean tacrolimus dose during itraconazole treatment was 3.26 ± 2.1 mg/d compared with 5.74 ± 2.9 mg/d after itraconazole was stopped, p < 0.0001. Similarly, the mean tacrolimus dose during voricnoazole treatment was 1.75 ± 0.9 mg/d compared with 4.85 ± 0.38 mg/d after voriconazole was stopped (p = 0.002). Thus, the mean increase in the total daily dose of tacrolimus after itraconazole and voriconazole withdrawal was 76% and 64%, respectively. No differences in the rejection or fungal infection rates or renal toxicity were observed during the study period, although an increase in positive fungal isolates was noted during itraconazole therapy. Conclusion: The tacrolimus dose was reduced more with itraconazole than with voriconazole, without an increase in the rejection rate and with renal function preservation.  相似文献   
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