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One obstacle to understanding the exact processes unfolding inside the hippocampus is that it is still difficult to clearly define what the hippocampus actually does, at the system level. Associated for a long time with the formation of episodic and semantic memories, and with their temporary storage, the hippocampus is also regarded as a structure involved in spatial navigation. These two independent perspectives on the hippocampus are not necessarily exclusive: proposals have been put forward to make them fit into the same conceptual frame. We review both approaches and argue that three critical developments need consideration: (a) recordings of neuronal activity in rodents, revealing beautiful spatial codes expressed in entorhinal cortex, upstream of the hippocampus; (b) comparative behavioral results suggesting, in an evolutionary perspective, qualitative similarity of function across homologous structures with a distinct internal organization; (c) quantitative measures of information, shifting the focus from who does what to how much each neuronal population expresses each code. These developments take the hippocampus away from philosophical discussions of all-or-none cause-effect relations, and into the quantitative mainstream of modern neural science.  相似文献   
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ObjectiveThe aim of the study is to compare the course and severity of narcolepsy in relation to different ages at the disease onset.MethodsClinical interviews with the completion of the Stanford questionnaire, Epworth Sleepiness Scale (ESS) and Multiple Sleep Latency Test (MSLT) were evaluated in 105 patients (44 males, 61 females, mean age 45.4 ± 19.2, BMI 29.2 ± 5.8) suffering from narcolepsy.ResultsThe severity of the disease was judged by clinical complaints, ESS value and MSLT results. No relations with the age at onset and clinical tetrad were found, however, smoking may be associated with an increased risk of hypnagogic hallucinations. There was no correlation between the number of sleep and cataplectic attacks and the age at onset, nor did subjective ESS show any significant dependence. However, earlier onset of the disease correlated with shorter MSLT mean latency. A correlation was found between the BMI and narcolepsy sleepiness rating in the elderly and between degree of education attained and subjective complaints.ConclusionsThe clinical severity of narcolepsy does not depend on the age at onset.  相似文献   
105.

Background

We have developed a Family Integrated Care (FIC) model for use in a neonatal intensive care unit (NICU) where parents provide most of the care for their infant, while nurses teach and counsel parents. The objective of this pilot prospective cohort analytic study was to explore the feasibility, safety, and potential outcomes of implementing this model in a Canadian NICU.

Methods

Infants born ≤35 weeks gestation, receiving continuous positive airway pressure or less respiratory support, with a primary caregiver willing and able to spend ≥8 hours a day with their infant were eligible. Families attended daily education sessions and were mentored at the bedside by nurses. The primary outcome was weight gain, as measured by change in z-score for weight 21 days after enrolment. For each enrolled infant, we identified two matched controls from the previous year’s clinical database. Differences in weight gain between the two groups were analyzed using a linear mixed effects multivariable regression model. We also measured parental stress levels using the Parental Stress Survey: NICU, and interviewed parents and nurses regarding their experiences with FIC.

Results

This study included 42 mothers and their infants. Of the enrolled infants, matched control data were available for 31 who completed the study. The rate of change in weight gain was significantly higher in FIC infants compared with control infants (p < 0.05). There was also a significant increase in the incidence of breastfeeding at discharge (82.1 vs. 45.5%, p < 0.05). The mean Parental Stress Survey: NICU score for FIC mothers was 3.06 ± 0.12 at enrolment, which decreased significantly to 2.30 ± 0.13 at discharge (p < 0.05). Feedback from the parents and nurses indicated that FIC was feasible and appropriately implemented.

Conclusions

This study suggests that the FIC model is feasible and safe in a Canadian healthcare setting and results in improved weight gain among preterm infants. In addition, this innovation has the potential to improve other short and long-term infant and family outcomes. A multi-centre randomized controlled trial is needed to further evaluate the efficacy of FIC in the Canadian context.
  相似文献   
106.
Objective The aim of this study was to evaluate the occurrence of egg allergy in patients over 14 years old suffering from atopic eczema and especially to evaluate if egg allergy can deteriorate the course of atopic eczema in this group of patients. Materials and methods Altogether 179 patients suffering from atopic eczema were included in the study: 51 men and 128 women, with an average age of 26.2 years (SD 9.5 years), with median SCORAD 31.6 (SD 13.3) points. A complete allergological and dermatological examination was performed on all patients, including diagnostic work‐up of food allergy to egg [skin prick tests, atopy patch tests (APTs), measurement of specific IgE level to egg yolks or whites]. Open exposure test (OET) with egg was performed in patients with positive results in some of these diagnostic methods. Food allergy to egg was determined according to positive results in the OET or according to sufficient anamnestical data about the severe allergic reaction after the ingestion of an egg. Results An allergy to egg was confirmed in 11 patients out of 179 (6%). Of these patients, only six (3.3%) had a clear improvement in the SCORAD after the elimination of egg. Other triggering factors may cause exacerbation of the atopic eczema in the patients enrolled in the study. Twenty‐eight percent of patients were only sensitized to egg without clinical symptoms. ATPs were a useful tool in the diagnosis of food allergy to egg in patients without IgE reactivity. Conclusion Egg allergy may play an important role in the worsening of atopic eczema acting as a triggering–exacerbating factor in a minority of patients. The diagnostic work‐up may comprise the challenge tests to confirm the food allergy to egg.  相似文献   
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108.

Objective

To determine conditional recurrence-free survival (RFS) and progression-free survival (PFS) and improve decision-making toward surveillance protocols and scheduling. Furthermore, evaluating the evolution of predictors for disease recurrence over time, because TaG1 non–muscle-invasive bladder cancer harbors a risk of disease recurrence and progression.

Material and methods

The retrospective multicenter design study includes 1,245 TaG1 bladder cancer patients with median follow-up of 62.7 (interquartile range: 34.3–91.1) months. Conditional RFS and PFS estimates were calculated using the Kaplan-Meier method. Multivariable Cox regression model was calculated proportional for the prediction of recurrence and progression (covariables: age, tumor size, multiple tumors, prior recurrence, and immediate postoperative instillation of chemotherapy).

Results

After 3 months without event, the conditional RFS and PFS (to ≥pT2) rates for 5 additional years without event were 57.5% and 93.4%, respectively. Given a 1-, 2-, 3-, and 5-year survival, the conditional RFS rates for 5 additional years without event improved by +9.8 (67.3%), +5.2 (72.5%), +6.5 (79.0%), +2.0 (81.0%), and +1.0% (82.0%), respectively. In contrast, the 5-year conditional PFS rates were more or less stable with 94.3% after 1 year to 94.1% after 5 years. Multivariable analyses showed decreasing impact of risk parameters on RFS estimates over time. Based on these findings, we suggest a risk stratification to individualize follow-up for intermediate risk TaG1. Main limitation was the retrospective design.

Conclusions

Conditional-survival analyses demonstrates that the patient risk profile changes over time. RFS rates rise with increasing survival whereas PFS rates were stable. The impact of prognostic features decreases over time. Our findings can be used for patient counseling and planning of personalized follow-up.  相似文献   
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The recently introduced class of micropole undulators, i.e., undulators with submilli-meter periods, promises a wide variety of useful applications in x-ray science and technology. One of the most important of these could turn out to be the efficient generation of highly coherent soft x rays on economical low-energy storage rings or linacs. Over the last year and a half, an intensive experimental effort has been in progress at the Lawrence Livermore National Laboratory (LLNL) to characterize the radiation emitted on a linac by a novel hybrid/bias micropole undulator fabricated at the Stanford Synchrotron Radiation Laboratory. In this initial report, the properties of this new 706-μm-period insertion device and its generation of 66-eV soft x rays on the LLNL linac are described. Although in the present experiment power levels of a fraction of a picowatt at linac currents of several tens of picoamperes were generated, this was in agreement with theoretical predictions. Operation of our prototype device on a higher energy machine at currents of several milliamperes could consequently be expected to produce milliwatt levels of soft x-ray output, making it an x-ray source potentially competitive with bending magnets on high-energy storage rings.  相似文献   
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