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81.
A long‐standing question in child language research concerns how children achieve mature syntactic knowledge in the face of a complex linguistic environment. A widely accepted view is that this process involves extracting distributional regularities from the environment in a manner that is incidental and happens, for the most part, without the learner's awareness. In this way, the debate speaks to two associated but separate literatures in language acquisition: statistical learning and implicit learning. Both fields have explored this issue in some depth but, at present, neither the results from the infant studies used by the statistical learning literature nor the artificial grammar learning tasks studies from the implicit learning literature can be used to fully explain how children's syntax becomes adult‐like. In this work, we consider an alternative explanation—that children use error‐based learning to become mature syntax users. We discuss this proposal in the light of the behavioral findings from structural priming studies and the computational findings from Chang, Dell, and Bock's (2006) dual‐path model, which incorporates properties from both statistical and implicit learning, and offers an explanation for syntax learning and structural priming using a common error‐based learning mechanism. We then turn our attention to future directions for the field, here suggesting how structural priming might inform the statistical learning and implicit learning literature on the nature of the learning mechanism.  相似文献   
82.
Variable selection is a crucial issue in model building and it has received considerable attention in the literature of survival analysis. However, available approaches in this direction have mainly focused on time-to-event data with right censoring. Moreover, a majority of existing variable selection procedures for survival models are developed in a frequentist framework. In this article, we consider additive hazards model in the presence of current status data. We propose a Bayesian adaptive least absolute shrinkage and selection operator procedure to conduct a simultaneous variable selection and parameter estimation. Efficient Markov chain Monte Carlo methods are developed to implement posterior sampling and inference. The empirical performance of the proposed method is demonstrated by simulation studies. An application to a study on the risk factors of heart failure disease for type 2 diabetes patients is presented.  相似文献   
83.
A typical time series in functional magnetic resonance imaging (fMRI) exhibits autocorrelation, that is, the samples of the time series are dependent. In addition, temporal filtering, one of the crucial steps in preprocessing of functional magnetic resonance images, induces its own autocorrelation. While performing connectivity analysis in fMRI, the impact of the autocorrelation is largely ignored. Recently, autocorrelation has been addressed by variance correction approaches, which are sensitive to the sampling rate. In this article, we aim to investigate the impact of the sampling rate on the variance correction approaches. Toward this end, we first derived a generalized expression for the variance of the sample Pearson correlation coefficient (SPCC) in terms of the sampling rate and the filter cutoff frequency, in addition to the autocorrelation and cross‐covariance functions of the time series. Through simulations, we illustrated the importance of the variance correction for a fixed sampling rate. Using the real resting state fMRI data sets, we demonstrated that the data sets with higher sampling rates were more prone to false positives, in agreement with the existing empirical reports. We further demonstrated with single subject results that for the data sets with higher sampling rates, the variance correction strategy restored the integrity of true connectivity.  相似文献   
84.
ObjectiveTo verify if the relationship between pain catastrophizing and pain worsening would be mediated by muscle weakness and disability in patients with symptomatic knee osteoarthritis.MethodsThis was a cross-sectional study in a hospital out-patient setting. Convenience sampling was used with a total of 50 participants with symptomatic knee osteoarthritis. Pain and the activities of daily livings (ADL) were assessed using the Knee Injury and Osteoarthritis Outcome Score (KOOS) subscale. Pain catastrophizing was assessed using the Coping Strategy Questionnaire (CSQ) subscale. Muscle strength of knee extension and 30-s chair stand test (30CST) were also assessed. Path analysis was performed to test the hypothetical model. Goodness of fit of models were assessed by using statistical parameters such as the chi-square value, goodness of fit index (GFI), adjusted goodness of fit index (AGFI), comparative fit index (CFI), and root mean square error of approximation (RMSEA).ResultsThe chi-square values were not significant (chi-square = 0.283, p = 0.594), and the indices of goodness of fit were high, implying a valid model (GFI = 1.000; AGFI = 0.997; CFI = 1.000; RMSEA = 0.000). Pain was influenced significantly by muscle strength and ADL; muscle strength was influenced significantly by ADL via 30CST; ADL was influenced by pain catastrophizing.ConclusionThe relationship between pain catastrophizing with pain worsening are mediated by muscle weakness and disability.  相似文献   
85.
于童  王静  张劲松 《国际眼科杂志》2019,19(8):1309-1312

白内障是我国首位致盲性眼病,也是世界上多数国家致盲的主要原因,目前手术是唯一有效的治疗方法。而后囊膜下混浊即后发性白内障(PCO)是白内障术后常见的并发症,也是导致术后视力下降的主要原因。研究表明,术后残留的晶状体上皮细胞(LECs)发生上皮间充质转化(EMT)在PCO的发生发展中起到了重要的作用。本文主要概述了近些年来EMT在PCO中的研究进展。  相似文献   

86.
目的 对社区医院人员防控知识强化测评模式的实施效果进行评价。方法 通过第三方数据收集平台,在规定时间内、实名制进行疫情防控知识问卷考核,以各岗位合格分数为标准,确认能否上岗,防控知识反复强化,题库动态更新,使各岗位人员保持高度认知的实战状态。结果 首次测试,医院全体人员新型冠状病毒肺炎防控知识平均分为78.37,100%的人知晓用过的一次性帽子和口罩的处理;只有23.27%的知晓医疗机构预检点或分诊台物品的消毒频次。强化测评模式实施1周后,医院全体人员新型冠状病毒肺炎防控知识平均分上升至93.84。上岗情况中,培训3 d上岗人数由48人上升至78人,培训第10天为149人,上岗率也由30.19%上升至第3天的49.05%,以及培训第10天的93.71%。结论 强制社区医院人员学习新型冠状病毒肺炎防控知识效果明显,整体水平短期内迅速提升,并保持高度认知,该强化测评模式对一线社区医院人员防控能力的提升有实际应用价值。  相似文献   
87.
BackgroundThe innovation of immune checkpoint blockade (ICB) represents a promising shift in the treatment of advanced hepatocellular carcinoma (HCC). However, response to ICB has varied largely due to the high tumor heterogeneity and complex tumor microenvironment (TME). The competitive endogenous RNA (ceRNA) network also plays an important role in tumor occurrence and progression, but its relation with tumor-infiltrating immune cells (TICs) remains largely unexplored in HCC. The overriding objective of our study was thus to construct a prognosis-related risk model and to further evaluate the relationship between ceRNA networks and TICs.MethodsDifferentially expressed gene (DEG) analysis was performed to identify the differentially expressed RNAs. Lasso and multivariable Cox regression analyses were used to construct risk models, which were assessed by the area under the receiver operating characteristic curve (AUC of ROC) and Kaplan-Meier (K-M) curves. Then, a single-sample gene set enrichment analysis (ssGSEA) algorithm was adopted to dissect the TICs in HCC samples. Nomograms were constructed and calibration curves were used to verify the discrimination and accuracy of the nomograms. Finally, integration analysis was performed to validate the correlation of ceRNA and TICs.ResultsIn the study, 7 differentially expressed RNAs [5 messenger RNA s (mRNAs) and 2 micro RNAs (miRNAs)] were incorporated to construct a ceRNA risk model. The AUC of the 1-, 3-, and 5-year overall survival (OS) were 0.784, 0.685, and 0.691 respectively. Likewise, 7 types TICs were in the TICs signature model and the AUC of the 1-, 3-, and 5-year OS were 0.706, 0.731, and 0.721 respectively. The integration analysis showed that 7 pairs of mRNA-TICs and 1 pair of miRNA-TICs had a close relation (all correlation coefficients >0.2, P<0.001).ConclusionsThrough constructing two risk models based on ceRNA network and TICs, we identified the hub RNAs and key TICs in the progression and prognosis of HCC, and further explored the relationship between ceRNA and TME. Importantly, targeting these hub RNAs may facilitate the remodeling of the TME and be a potential therapeutic alternative to enhancing the response to ICB, thus improving the prognosis of HCC patients.  相似文献   
88.
ATP6L, the C subunit of the V‐ATPase V0 domain, is involved in regulating the acidic tumor micro‐environment and may promote tumor progression. However, the expression and functional role of ATP6L in tumors have not yet been well explored. In this study, we found that ATP6L protein overexpression was related to colorectal cancer histological differentiation (P < 0.001), presence of metastasis (P < 0.001) and recurrence (P = 0.02). ATP6L expression in the liver metastatic foci was higher than in the primary foci (P = 0.04). ATP6L expression was notably concomitant with epithelial‐mesenchymal transition (EMT) immunohistochemical features, such as reduced expression of the epithelial marker E‐cadherin (P = 0.021) and increased expression of the mesenchymal marker vimentin (P = 0.004). Results of in vitro and in vivo experiments showed that ATP6L expression could alter cell morphology, regulate EMT‐associated protein expression, and enhance migration and invasion. The effect of ATP6L on metastasis was further demonstrated in a tail vein injection mice model. In addition, the mouse xenograft model showed that ATP6L‐overexpressing HCT116 cells grew into larger tumor masses, showed less necrosis and formed more micro‐vessels than the control cells. Taken together, our results suggest that ATP6L promotes metastasis of colorectal cancer by inducing EMT and angiogenesis, and is a potential target for tumor therapy.  相似文献   
89.
BackgroundEarly detection of consciousness after severe brain injury is critical for establishing an accurate prognosis and planning appropriate treatment.ObjectivesTo determine which behavioural signs of consciousness emerge first and to estimate the time course to recovery of consciousness in patients with severe acquired brain injury.MethodsRetrospective observational study using the Coma Recovery Scale-Revised and days to recovery of consciousness in 79 patients (51 males; 34 with traumatic brain injury; median [IQR] age 48 [26–61] years; median time since injury 26 [20–36] days) who transitioned from coma or unresponsive wakefulness syndrome (UWS)/vegetative state (VS) to the minimally conscious state (MCS) or emerged from MCS during inpatient rehabilitation.ResultsVisual pursuit was the most common initial sign of MCS (41% of patients; 95% CI [30–52]), followed by reproducible command-following (25% [16–35]) and automatic movements (24% [15–33]). Ten other behaviours emerged first in less than 16% of cases. Median [IQR] time to recovery of consciousness was 44 [33–59] days. Etiology did not significantly affect time to recovered consciousness.ConclusionRecovery of consciousness after severe brain injury is most often signalled by reemergence of visual pursuit, reproducible command-following and automatic movements. Clinicians should use assessment measures that are sensitive to these behaviours because early detection of consciousness is critical for accurate prognostication and treatment planning.  相似文献   
90.
Abstract

The aim of this study was to analyze clinical manifestations of 565 ovarian hyperstimulation syndrome (OHSS) inpatients in the largest Obstetrics and Gynecology hospital in China from year 2010 to 2017, to get more understanding of epidemiologic features of this disease, and to provide some insight on the diagnosis, treatment, and preventions of OHSS. It is a clinical retrospective study. In the 565 cases that developed OHSS over an eight-year period between 2010 and 2017 were reviewed, we assessed patients’ general characteristics, clinical manifestations, treatment, prognosis, and the relationship between different indicators and the severity of OHSS. Totally 12 kinds of ovulation induction protocols (Protocol 1: CC; Protocol 2: Gn; Protocol 3: hCG; Protocol 4: GnRh-a; Protocol 5: CC & Gn; Protocol 6: CC & hCG; Protocol 7: Gn & hCG; Protocol 8: GnRh-a & Gn; Protocol 9: CC & Gn & hCG; Protocol 10: GnRh-a & CC & Gn; Protocol 11: Letrozole & Gn & hCG; Protocol 12:GnRh-a & Letrozole & Gn) were analyzed and the Odds Ratio (OR) of each protocol were calculated. Five hundred and sixty-five patients were reviewed in our study. In all these patients, the number of hospitalizations, mean age, primary infertility rate, and pregnancy rate did not differ through the last 8?years. From which we may infer that the incidence rate of OHSS may not change over the last 8?years. Older patients tend to develop into more severe stage easily. The pregnancy rate was much lower in mild stage patients, but no difference was found between patients in moderate, severe and critical stage. Oocytes retrieval is strongly associated with severity. PCOS history, irregular menstrual cycle and infertility type do not seem to affect the severity of OHSS. Twelve kinds of ovulation induction protocols were analyzed, OR of different protocols were calculated, what is noteworthy is that patients who used GnRh easily developed more severe OHSS than the patients who received oocytes retrieval. We suggest that we may choose ovulation induction protocols according to the OR table while treating women with high-risk factors.  相似文献   
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