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1.
Abstract: Aim: To compare plaque removal efficacy of Oral‐B CrossAction (CA) used for 1 min with an American Dental Association (ADA) manual toothbrush used for 2 or 5 min in an examiner‐blind, three‐treatment, six‐period crossover study. Materials and methods: After refraining from all oral hygiene procedures for 23–25 h, subjects were randomly assigned to one of nine possible six‐period (visit) treatment sequences. Plaque was assessed at baseline (Rustogi Modified Navy Plaque Index). Post‐brushing scores were recorded after brushing with a marketed dentifrice and the assigned toothbrush for the specified duration. The same procedure was followed at each of six subsequent visits. Clinical measurements were carried out by the same examiner. Results: Forty subjects completed the study. All three treatments effectively removed plaque from the whole mouth, along the gingival margin and from approximal surfaces. Whole mouth and gingival margin plaque removal scores with CA for 1 min did not differ significantly from scores with the ADA toothbrush used for 2 min. The ADA brush used for 5 min showed significantly greater whole mouth (P < 0.001) and gingival margin (P < 0.001) plaque reduction than the two other treatments. Approximal plaque removal scores did not differ between the three treatments. Conclusions: Efficient plaque removal can be achieved after 1 min of brushing with CA. The amount of plaque removed did not differ significantly from that achieved with the ADA brush after 2 min of brushing. Greater whole mouth and gingival margin plaque removal scores were seen with the ADA brush after 5 min.  相似文献   
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背景 冠状动脉无复流是影响急性ST段抬高型心肌梗死(STEMI)患者急诊经皮冠状动脉介入治疗(PCI)效果的重要因素,影响患者预后,增加死亡风险。寻求有效的药物提高PCI手术效果,降低术中无复流的发生率具有重要意义。目的 探讨冠状动脉内直接注入比伐芦定联合静脉泵入对比单静脉泵入比伐芦定对急性STEMI患者术中无复流的影响及其安全性和短期临床预后观察。方法 选取2017年6月-2019年1月于新疆医科大学附属中医医院明确诊断为急性STEMI发病12 h内并行PCI的住院患者110例,随机分为冠状动脉内直接注入联合静脉泵入比伐芦定组(观察组,n=55)和单纯静脉泵入比伐芦定组(对照组,n=55)。比较两组术中、术后观察指标〔病变血管支数、梗死相关血管(IRA)、术前靶血管TIMI血流分级、Gensini评分、门-球(D-to-B)时间、血栓抽吸例数、支架植入数量、后扩张、术后应用血管紧张素转换酶抑制剂(ACEI)或血管紧张素Ⅱ受体拮抗剂(ARB)比例、术后应用β-受体阻滞剂比例〕、疗效评价指标〔术中植入支架即刻造影IRA的校正的TIMI帧数计数(CTFC),无复流/慢血流发生率,术后4 h内心电图ST段回落程度,术后24 h的肌酸激酶同工酶(CK-MB),术后24 h左心室射血分数(LVEF)〕、30 d内主要心血管不良事件(MACE)发生率;采用多因素Logistic回归分析探讨冠状动脉内直接注入比伐芦定联合静脉泵入对部分疗效指标的影响。结果 两组患者术中、术后观察指标比较,差异无统计学意义(P>0.05)。两组PCI术中即刻CTFC、无复流/慢血流发生率及ST段回落情况比较,差异有统计学意义(P<0.05)。多因素Logistic回归分析结果显示,冠状动脉内直接注入比伐芦定联合静脉泵入治疗急性STEMI,可以降低患者术中CTFC〔OR=0.423,95%CI(0.321,0.656),P=0.005〕,是术后无复流/慢血流〔OR=0.431,95%CI(0.262,0.812),P=0.002〕的保护因素,并促进术后4 h内心电图ST段的回落〔OR=1.532,95%CI(0.627,2.517),P=0.003〕。结论 冠状动脉内直接注入比伐芦定联合静脉泵入可降低STEMI患者术后无复流发生率,可降低心力衰竭及死亡风险,且安全性良好,可改善患者短期临床预后。  相似文献   
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Previous studies have observed poorer working memory performance in individuals with amnestic mild cognitive impairment than in healthy older adults. It is unclear, however, whether these difficulties are true only of the multiple-domain clinical subtype in whom poorer executive functioning is common. The current study examined working memory, as measured by the self-ordered pointing task (SOPT) and an n-back task, in healthy older adults and adults with single-domain amnestic mild cognitive impairment (aMCI). Individuals with single-domain aMCI committed more errors and required longer to develop an organizational strategy on the SOPT. The single-domain aMCI group did not differ from healthy older adults on the 1-back or 2-back, but had poorer discrimination on the 3-back task. This is, to our knowledge, the first characterization of dynamic working memory performance in a single-domain aMCI group. These results lend support for the idea that clinical amnestic MCI subtypes may reflect different stages on a continuum of progression to dementia and question whether standardized measures of working memory (span tasks) are sensitive enough to capture subtle changes in performance.  相似文献   
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Introduction

The median survival of patients with glioblastoma multiforme (astrocytoma grade 4) remains less than 18 months despite radical surgery, radiotherapy and systemic chemotherapy. Surgical implantation of chemotherapy eluting wafers into the resection cavity has been shown to improve length of survival but the current licensed therapy has several drawbacks. This paper investigates in vivo efficacy of a novel drug eluting paste in glioblastoma.

Methods

Poly(lactic-co-glycolic acid)/poly(ethylene glycol) (PLGA/PEG) self-sintering paste was loaded with the chemotherapeutic agent etoposide and delivered surgically into partially resected tumours in a flank murine glioblastoma xenograft model.

Results

Surgical delivery of the paste was successful and practical, with no toxicity or surgical morbidity to the animals. The paste was retained in the tumour cavity, and preliminary results suggest a useful antitumour and antiangiogenic effect, particularly at higher doses. Bioluminescent imaging was not affected significantly by the presence of the paste in the tumour.

Conclusions

Chemotherapy loaded PLGA/PEG paste seems to be a promising technology capable of delivering active drugs into partially resected tumours. The preliminary results of this study suggest efficacy with no toxicity and will lead to larger scale efficacy studies in orthotopic glioblastoma models.  相似文献   
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Chronic stress and depression have adverse consequences on many organ systems, including the skeleton, but the mechanisms underlying stress‐induced bone loss remain unclear. Here we demonstrate that neuropeptide Y (NPY), centrally and peripherally, plays a critical role in protecting against stress‐induced bone loss. Mice lacking the anxiolytic factor NPY exhibit more anxious behavior and elevated corticosterone levels. Additionally, following a 6‐week restraint, or cold‐stress protocol, Npy‐null mice exhibit three‐fold greater bone loss compared to wild‐type mice, owing to suppression of osteoblast activity. This stress‐protective NPY pathway acts specifically through Y2 receptors. Centrally, Y2 receptors suppress corticotropin‐releasing factor expression and inhibit activation of noradrenergic neurons in the paraventricular nucleus. In the periphery, they act to control noradrenaline release from sympathetic neurons. Specific deletion of arcuate Y2 receptors recapitulates the Npy‐null stress response, coincident with elevated serum noradrenaline. Importantly, specific reintroduction of NPY solely in noradrenergic neurons of otherwise Npy‐null mice blocks the increase in circulating noradrenaline and the stress‐induced bone loss. Thus, NPY protects against excessive stress‐induced bone loss, through Y2 receptor‐mediated modulation of central and peripheral noradrenergic neurons. © 2014 American Society for Bone and Mineral Research.  相似文献   
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