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81.
Early Alzheimer's disease (AD) is associated with deficits in episodic memory. Semantic memory and naming have also been found to be affected, although to a lesser degree than episodic memory. Most episodic memory tests used in clinical settings assess intentional memory. The aim of the present paper was to present an incidental memory modification of the Boston Naming Test (memo-BNT) and to study the diagnostic accuracy of the BNT and the memo-BNT in differentiating between healthy old controls and AD patients. There were three groups in the study: 22 young controls (mean age 21.7), 23 normally aged old controls (mean age 70.6), and 23 patients with mild AD (mean age 74.0). There were no differences in the memo-BNT test scores between the old and young control participants. There were, however, significant differences between the AD patients and both control groups in several of the memo-BNT measures. Incidental free recall was the best measure in discriminating between the healthy aged controls and the AD patients (AUC?=?.939) and it had a better diagnostic accuracy than naming (AUC?=?880). The results indicate that the memo-BNT could be used in clinical settings especially to differentiate between normal aging and mild AD.  相似文献   
82.
目的:总结以病人为中心的口腔科门诊数字化建设的经验。方法:从诊疗手段、就医流程、医疗文书以及科室管理4个方面总结广州军区武汉总医院口腔科门诊数字化建设的概况。结果:2009年以来开始进行El腔科门诊的数字化建设,经过3年多的运行,科室工作流程优化明显,提高了工作效率和医疗服务质量。结论:科室的数字化建设有助于提高科室的工作效率和医疗服务质量,充分体现了”以病人为中心”这一理念。  相似文献   
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85.

Background

The level of platelet reactivity (PR) inhibition obtained after P2Y12-ADP receptor antagonist loading dose (LD) is associated with the ischemic and bleeding risk following percutaneous coronary intervention (PCI) in acute coronary syndromes (ACS).

Objective

We aimed to evaluate the level of PR inhibition achieved by a 180 mg LD of ticagrelor and the rate of high on-treatment platelet reactivity (HTPR) in ACS patients undergoing PCI.

Methods

We performed a multicentre prospective observational study enrolling ACS patients undergoing PCI. Patients were included if they were admitted for ST-elevation myocardial infarction or non ST-elevation ACS. To assess PR, a VASP index was measured at least 6 and within 24 hours following a 180 mg LD of ticagrelor. HTPR was defined as a VASP index ≥ 50%.

Results

One hundred and fifteen patients were included: 31.3% of STEMI, 49.6% of NSTEMI and 19.1% of unstable angina. Following ticagrelor LD the mean VASP index was 17 ± 14%. However the response to ticagrelor was not uniform with a small inter-individual variability: inter quartile range: 7.6–22.8% and a rate of HTPR of 3.5%. A high number of patients, 65.6%, had a VASP index < 16%. None of the baseline characteristics of the study population was associated with PR. In addition, PR was similar in STEMI, NSTEMI and unstable angina (p = 0.9).

Conclusion

In ACS patients the level of PR inhibition achieved by a 180 mg loading dose of ticagrelor is not uniform and the rate of HTPR is 3.5%. A high proportion of patients exhibited a VASP index < 16%.  相似文献   
86.
Background: Many therapy techniques for word retrieval disorders use some form of priming to improve access to words. Priming can facilitate or interfere with naming under different circumstances. We examined effects of priming when combined with semantic or phonological context (training words in groups that are semantically or phonologically related) and how these effects interact with the type of naming impairment (semantically or phonologically based). Aims: We addressed three questions (1) Are word retrieval impairments differentially sensitive to priming with semantic or phonological contexts? (2) Would such differences be systematically related to deficits of semantic versus phonological processing? (3) Do effects of priming evolve from immediate interference to short‐term facilitation, as predicted by an interactive activation model of word retrieval? Methods & Procedures: A total of 11 chronic English‐speaking aphasic subjects with varied types of aphasia participated in this experiment. Background measures of semantic and phonological processing ability were administered to determine the nature of each subject's naming impairment. The experiment involved one‐session facilitation treatments for each of three context conditions (semantic, phonological, and unrelated), plus three replications (nine subjects) or one replication (two subjects). Ten pictures in each condition were tested before and after treatment. Five pictures were trained and five served as controls. Participants repeated the name of each picture four times (repetition priming) and then attempted to name each picture individually (naming probe). Repetition priming and naming probes were repeated eight times. We used McNemar tests to compare rates of correct responses before and after priming, and chi square analyses of correct responses and contextual errors on naming probes obtained during the priming sessions. Outcome & results: Our predictions were borne out in the data. Participants varied in their sensitivity to the semantic and phonological contexts. The error data suggest that interference during training is more likely when the context (semantic or phonological) and underlying source of the word processing impairment (semantic or phonological) match. Additionally, we found two sequential effects of contextual priming: immediate interference followed short‐term facilitation. Conclusions: These data have theoretical implications regarding the time course of priming effects, but also have important clinical implications. The present contextual priming procedure is relatively short and could be used as a predictor of performance patterns in a long‐term treatment protocol that uses this approach or other tasks that employ priming.  相似文献   
87.
Background: The study of novel word learning in aphasia can shed light on the functionality of patients' learning mechanisms and potentially help in treatment planning. Previous studies have indicated that persons with aphasia are able to learn some new vocabulary. However, these learning outcomes appear short-lived and evidence for the ability to use the newly learned words in the long term is lacking.

Aims: Participants with aphasia and matched controls underwent short training where they were taught to name novel objects with novel names. We studied the participants' word learning and particularly their long-term maintenance. We also examined whether the language and verbal short-term memory impairments of the participants with aphasia related to their ability to acquire and maintain phonological and semantic information on novel words.

Methods & Procedures: Two participants with nonfluent aphasia, LL and AR, and two matched controls took part in the experiment. They were taught to name 20 unfamiliar objects by repeating the names in the presence of the object picture. Half of the items carried a definition that was used to probe incidental semantic learning. There were four training sessions, a post-training test, and follow-up tests up to 6 months post-training. Learning measures included recognition of the trained objects, as well as spontaneous and cued recall in visual confrontation naming. Incidental semantic learning was measured by spontaneous recall of the definitions.

Outcomes & Results: Combining spontaneous and phonologically cued responses, LL acquired 70% and AR 55% of the novel words. With phonological cueing, LL named 50% of the items correctly up to 6 months post-training (vs 95–100% for the controls) and AR 25% up to 8 weeks post-training. AR's lexical-semantic processing, pseudoword repetition and verbal short-term capacity were inferior to those of LL. In line with this, AR learned fewer words and showed more decline in recognition memory for the trained items, and weaker recall of the semantic definitions.

Conclusions: Our results support previous findings that people with aphasia can learn to name novel items. More importantly, the results show for the first time that, with phonological cueing, an individual with aphasia can maintain some of this learning up to 6 months post-training. Moreover the results provide further evidence for the significance of the functional status of lexical-semantic processing on word learning success.  相似文献   
88.
无私和信任是人体试验研究的核心。自愿参加研究的受试者是无私的,因为他们相信自己的参与将为他人健康的改善做出贡献,也相信研究者会尽最大努力减少受试者的风险。由于受试者的无私和信任,临床研究才成为可能,因此研究机构有义务使临床研究的实施符合伦理学要求,并诚实地报道研究结果。而诚实的报道首先需要知道所有现存的临床研究,即使其结果对赞助方不利。  相似文献   
89.

Introduction

The retrojugular approach for carotid endarterectomy (CEA) has been reported to have the advantages of shorter operative time and ease of dissection, especially in high carotid lesions. Controversial opinion exists with regard to its safety and benefits over the conventional antejugular approach.

Methods

A systematic review of electronic information sources was conducted to identify studies comparing outcomes of CEA performed with the retrojugular and antejugular approach. Synthesis of summary statistics was undertaken and fixed or random effects models were applied to combine outcome data.

Findings

A total of 6 studies reporting on a total of 740 CEAs (retrojugular approach: 333 patients; antejugular approach: 407 patients) entered our meta-analysis models. The retrojugular approach was found to be associated with a higher incidence of laryngeal nerve damage (odds ratio [OR]: 3.21, 95% confidence interval [CI]: 1.46–7.07). No significant differences in the incidence of hypoglossal or accessory nerve damage were identified between the retrojugular and antejugular approach groups (OR: 1.09 and 11.51, 95% CI: 0.31–3.80 and 0.59–225.43). Cranial nerve damage persisting during the follow-up period was similar between the groups (OR: 2.96, 95% CI: 0.79–11.13). Perioperative stroke and mortality rates did not differ in patients treated with the retrojugular or antejugular approach (OR: 1.26 and 1.28, 95% CI: 0.31–5.21 and 0.25–6.50).

Conclusions

Currently, there is no conclusive evidence to favour one approach over the other. Proof from a well designed randomised trial would help determine the role and benefits of the retrojugular approach in CEA.  相似文献   
90.
The first step of cellular entry for the human immunodeficiency virus type-1 (HIV-1) occurs through the binding of its envelope protein (Env) with the plasma membrane receptor CD4 and co-receptor CCR5 or CXCR4 on susceptible cells, primarily CD4+ T cells and macrophages. Although there is considerable knowledge of the molecular interactions between Env and host cell receptors that lead to successful fusion, the precise way in which HIV-1 receptors redistribute to sites of virus binding at the nanoscale remains unknown. Here, we quantitatively examine changes in the nanoscale organisation of CD4 on the surface of CD4+ T cells following HIV-1 binding. Using single-molecule super-resolution imaging, we show that CD4 molecules are distributed mostly as either individual molecules or small clusters of up to 4 molecules. Following virus binding, we observe a local 3-to-10-fold increase in cluster diameter and molecule number for virus-associated CD4 clusters. Moreover, a similar but smaller magnitude reorganisation of CD4 was also observed with recombinant gp120. For one of the first times, our results quantify the nanoscale CD4 reorganisation triggered by HIV-1 on host CD4+ T cells. Our quantitative approach provides a robust methodology for characterising the nanoscale organisation of plasma membrane receptors in general with the potential to link spatial organisation to function.  相似文献   
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