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11.
The phonology of two groups of SLI (n =5) and LD (n =5) children was analysed at age 3 and compared with two control groups: an age control (n =5) and a language level control (measured using the MLU-W) (n =5). Children with SLI and LD showed a delay in the acquisition of segments, syllabic structures and word structures, and in the simplification processes, compared with their age control group. However, SLI children also displayed significant differences vis-à-vis their language level controls, mainly in early acquisitions: vowels, nasals and stops at the segmental level, and in CV structures at the syllabic level. There is also a simplification process that seems to be more prevalent in these children than in their language level controls, namely, the deletion of unstressed syllables, mainly initial ones. The results enable SLI to be distinguished from LD and suggest that the development of SLI phonology is deviant. This deviation is interpreted as being a plateau in early acquisitions when later acquisitions have already appeared. The results are considered in the light of Leonard's surface hypothesis and an exclusively linguistic cause for this disorder is ruled out.  相似文献   
12.
The naming and drawing responses of a child with specific language impairment (age 5.5 years) were used to test the hypothesis that deficient storage in the mental lexicon plays a role in the naming problems associated with SLI. In confrontation- and repeated naming, the child demonstrated frequent semantic substitutions and occasional phonologic substitutions. Stochastic modelling of his repeated naming revealed storage deficits to be a source of these errors. Comparative picture naming, picture drawing allowed exploration of this storage deficit and revealed that, for some semantic naming errors, sparse semantic representations were clearly at fault but for others, sparse phonological input and output representations played a role. Phonological naming errors, in contrast, were typically associated with strong semantic representations. Clinical, theoretical, and methodological contributions of this cognitive neuropsychological case study are discussed.  相似文献   
13.
ObjectiveTo determine differences between continuous videofluoroscopic swallow studies (VFSS) with a pulse rate and frame rate of 30 and the same swallows reduced to 15 frames per second (fps) on measures of swallowing function in patients after acute ischemic stroke.DesignBlinded comparison.SettingAcute hospital.ParticipantsPatients after ischemic stroke (N=20).InterventionsNot applicable.Main Outcome MeasuresSingle and sequential sips of thin liquids, single sips of nectar liquids, pudding, and cookie boluses were rated on measures of timing of swallowing events, Modified Barium Swallowing Impairment Profile component scores, and Penetration-Aspiration Scale scores. The ratings for videos at 15 fps and 30 fps were compared by Wilcoxon signed rank tests.ResultsPharyngeal transit time was longer and bolus entry into the hypopharynx was later for 30 fps than for 15 fps. Components of Oral Residue and Pharyngoesophageal Segment Opening ratings were more severe for 15 fps than 30 fps, whereas Bolus Transport and Initiation of Pharyngeal Swallow were rated as more severe for 30 fps than for 15 fps. There was no difference between 30 fps and 15 fps on the remaining measures, including Penetration-Aspiration Scale scores.ConclusionContinuous VFSS recorded at 30 fps and their down-sampled 15 fps duplicates yielded contrasting results on certain durational and functional measures of swallowing, though not on others. VFSS should be administered continuously or at 30 pulses per second for valid assessment of swallowing while using other methods to reduce radiation exposure.  相似文献   
14.
BackgroundHeadache disorders are disabling, with major consequences for productivity, yet the literature is silent on the relationship between headache-attributed disability and lost productivity, often erroneously regarding the two as synonymous. We evaluated the relationship empirically, having earlier found that investment in structured headache services would be cost saving, not merely cost-effective, if reductions in headache-attributed disability led to > 20% pro rata recovery of lost productivity.MethodsWe used individual participant data from Global Campaign population-based studies conducted in China, Ethiopia, India, Nepal, Pakistan and Russia, and from Eurolight in Lithuania, Luxembourg and Spain. We assessed relationships in migraine and probable medication-overuse headache (pMOH), the most disabling common headache disorders. Available symptom data included headache frequency, usual duration and usual intensity. We used frequency and duration to estimate proportion of time in ictal state (pTIS). Disability, in the sense used by the Global Burden of Disease study, was measured as the product of pTIS and disability weight for the ictal state. Impairment was measured as pTIS * intensity. Lost productivity was measured as lost days (absence or < 50% productivity) from paid work and corresponding losses from household work over the preceding 3 months. We used Spearman correlation and linear regression analyses.ResultsFor migraine, in a linear model, we found positive associations with lost paid worktime, significant (p < 0.05) in many countries and highly significant (p < 0.001) in some despite low values of R2 (0–0.16) due to high variance. With lost household worktime and total lost productivity (paid + household), associations were highly significant in almost all countries, although still with low R2 (0.04–0.22). Applying the regression equations for each country to the population mean migraine-attributed disability, we found pro rata recoveries of lost productivity in the range 16–56% (> 20% in all countries but Pakistan). Analysing impairment rather than disability increased variability. For pMOH, with smaller numbers, associations were generally weaker, occasionally negative and mostly not significant.ConclusionRelief of disability through effective treatment of migraine is expected, in most countries, to recover > 20% pro rata of lost productivity, above the threshold for investment in structured headache services to be cost saving.  相似文献   
15.
16.
BackgroundFamily history (FH) of cardiovascular (CV) disease is a known CV risk factor. However, it is rarely considered for CV risk stratification. Furthermore, FH for metabolic diseases is generally overlooked.AimTo evaluate, in a population of men with erectile dysfunction (ED), whether FH for cardio-metabolic diseases could provide insights into metabolic and sexual features and predict the occurrence of forthcoming major adverse CV events (MACE).MethodsA consecutive series of 4,693 individuals (aged 51.3 ± 13.3 years) attending an Andrology outpatient clinic for ED was studied. A subset of these (n = 1,595) was evaluated retrospectively for MACE occurrence.OutcomesSeveral metabolic and sexual function–related parameters were studied. For the retrospective study, information on an incident MACE was collected over a mean follow-up of 4.2 ± 2.5 years.ResultsA greater number of cardio-metabolic FH factors were associated with a worse metabolic profile, including higher waist circumference, triglycerides, glucose, glycosylated hemoglobin, and diastolic blood pressure, as well as lower high-density lipoprotein cholesterol. An increased number of FH factors were associated with worse erectile function (odds ratio = 1.14[1.07;1.23], P < .0001), impaired penile dynamic peak systolic velocity, and lower testosterone levels. In the retrospective study, a positive cardiometabolic FH was associated with a significantly higher incidence of MACEs, even after adjusting for age and comorbidities (hazard ratio = 1.51[1.06-2.16], P = .023). Interestingly, when dividing the sample into high- and low-risk categories according to several CV risk factors (age, previous MACEs, high-density lipoprotein cholesterol, and comorbidities), FH was confirmed as a predictor of incident MACE only among the low-risk individuals.Clinical ImplicationsInvestigating FH for cardio-metabolic diseases is a quick and easy task that could help clinicians in identifying, among individuals with ED, those who deserve careful evaluation of CV and metabolic risk factors. Moreover, considering FH for CV risk stratification could predict MACEs in individuals who, according to conventional CV risk factors, would be erroneously considered at low risk.Strengths & LimitationsThe large sample size and the systematic collection of MACEs through an administrative database, with no risk of loss at follow-up, represent strengths. The use of administrative database for MACE collection may lead to some misclassifications. The specific population of the study limits the generalizability of the results.ConclusionFH is simple and inexpensive information that should be part of the CV risk assessment in all men with ED because it helps in the identification of those who need lifestyle and risk factor modifications and whose risk would otherwise be overlooked.Rastrelli G, Yannas D, Mucci B, et al. Family History for Cardio-Metabolic Diseases: A Predictor of Major Adverse Cardiovascular Events in Men With Erectile Dysfunction. J Sex Med 2020;17:2370–2381.  相似文献   
17.
OBJECTIVE:To determine the effects of a formal auditory training program on the behavioral, electrophysiological and subjective aspects of auditory function in individuals with bilateral high-frequency hearing loss.METHOD:A prospective study of seven individuals aged 46 to 57 years with symmetric, moderate high-frequency hearing loss ranging from 3 to 8 kHz was conducted. Evaluations of auditory processing (sound location, verbal and non-verbal sequential memory tests, the speech-in-noise test, the staggered spondaic word test, synthetic sentence identification with competitive ipsilateral and contralateral competitive messages, random gap detection and the standard duration test), auditory brainstem response and long-latency potentials and the administration of the Abbreviated Profile of Hearing Aid Benefit questionnaire were performed in a sound booth before and immediately after formal auditory training.RESULTS:All of the participants demonstrated abnormal pre-training long-latency characteristics (abnormal latency or absence of the P3 component) and these abnormal characteristics were maintained in six of the seven individuals at the post-training evaluation. No significant differences were found between ears in the quantitative analysis of auditory brainstem responses or long-latency potentials. However, the subjects demonstrated improvements on all behavioral tests. For the questionnaire, the difference on the background noise subscale achieved statistical significance.CONCLUSION:Auditory training in adults with high-frequency hearing loss led to improvements in figure-background hearing skills for verbal sounds, temporal ordination and resolution, and communication in noisy environments. Electrophysiological changes were also observed because, after the training, some long latency components that were absent pre-training were observed during the re-evaluation.  相似文献   
18.
去势大鼠干眼症模型眼表损伤的研究   总被引:1,自引:0,他引:1  
建立去势大鼠干眼症模型并对其眼表损伤进行研究。60只Wistar大鼠随机分为6组,每组10只。A组为雌性对照组,B组为雌性假手术组,C组为雌性去势组,D组为雄性对照组,E组为雄性假手术组,F组为雄性去势组。A组与D组大鼠正常饲养,不作处理。C组大鼠去除卵巢,B组重复手术过程但不去除大鼠卵巢,F组大鼠去除双侧睾丸及附睾,E组大鼠重复手术过程但不去除睾丸及附睾。所有大鼠均与术前及术后2、4、6月进行泪液分泌量、角膜上皮荧光素染色和泪膜破裂时间检测。A、B、D、E组大鼠泪液分泌量、角膜上皮荧光素染色和泪膜破裂时间检测均差异不显著(P>0.05)。去势组大鼠(组C和组F)角膜荧光染色在术后2月起为阳性,并随时间增加而加重。去势6月后,去势组(组C和组F)的泪液分泌量、泪膜破裂时间与其他组相比差异极显著(P<0.01),并且C组与F组相比差异极显著(P<0.01)。大鼠去势后造成眼表损伤可能是干眼症原因之一。  相似文献   
19.

Background

The World Wide Web allows access to patient/care partner perspectives on the lived experience of dementia. We were interested in how symptoms that care partners target for tracking relate to dementia stage, and whether dementia could be staged using only these online profiles of targeted symptoms.

Objectives

To use clinical data where the dementia stage is known to develop a model that classifies an individual’s stage of dementia based on their symptom profile and to apply this model to classify dementia stages for subjects from a Web-based dataset.

Methods

An Artificial Neural Network (ANN) was used to identify the relationships between the dementia stages and individualized profiles of people with dementia obtained from the 60-item SymptomGuide (SG). The clinic-based training dataset (n=320), with known dementia stages, was used to create an ANN model for classifying stages in Web-based users (n=1930).

Results

The ANN model was trained in 66% of the 320 Memory Clinic patients, with the remaining 34% used to test its accuracy in classification. Training and testing staging distributions were not significantly different. In the 1930 Web-based profiles, 309 people (16%) were classified as having mild cognitive impairment, 36% as mild dementia, 29% as moderate, and 19% as severe. In both the clinical and Web-based symptom profiles, most symptoms became more common as the stage of dementia worsened (eg, mean 5.6 SD 5.9 symptoms in the MCI group versus 11.9 SD 11.3 in the severe). Overall, Web profiles recorded more symptoms (mean 7.1 SD 8.0) than did clinic ones (mean 5.5 SD 1.8). Even so, symptom profiles were relatively similar between the Web-based and clinical datasets.

Conclusion

Symptoms targeted for online tracking by care partners of people with dementia can be used to stage dementia. Even so, caution is needed to assure the validity of data collected online as the current staging algorithm should be seen as an initial step.  相似文献   
20.
戊二酸尿症Ⅰ型是戊二酰辅酶A脱氢酶基因缺陷引起的常染色体隐性遗传病.患儿常因急性脑病危象诱发严重的纹状体退行性变化及锥体外系后遗症.戊二酰辅酶A脱氢酶缺陷致戊二酸、3-羟基戊二酸等代谢物在体内异常蓄积,尤其是脑部,致神经毒性.但是基因突变所致的残留酶活性和表型间并无相关性,该病发病机制复杂.近年来,研究表明戊二酸等代谢累积物在中枢神经系统内源性生成且不易通过血脑屏障而在脑内蓄积致神经毒性.目前,对神经毒性机制的研究除了兴奋性损伤、能量代谢受损和氧化应激三大方面,还包括胶质活化、血管损伤、炎症因子等其他方面.  相似文献   
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