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91.
Lumbar puncture for testing of Alzheimer’s disease pathophysiology for diagnostic confirmation is likely to become more common in the coming years. Minimizing adverse effects from this testing will be essential for clinical practice. Small bore, atraumatic needles reduce the occurrence of post-lumbar puncture headache (PLPH). Our goal was to extend this recommendation specifically to a well-characterized aging population. We assessed PLPH in the Alzheimer’s Disease Neuroimaging Initiative cohort and found that PLPH occurrence was reduced only when using a 24 gauge atraumatic needle. We recommend that lumbar punctures for clinical and research purposes in Alzheimer’s disease be conducted with 24 gauge atraumatic needles.  相似文献   
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93.
The increased prevalence of atrial fibrillation (AF) has led to specialized AF clinics (AFCs) to facilitate management of AF patients. In this article we report on outpatient AFCs in Canada, which is essential to health policies required to standardize the performance of existing AFCs and help design new AFCs. We surveyed 14 clinics in 5 provinces; 100% provided responses to a detailed questionnaire on clinic processes and care practices. Fourteen care maps were analyzed, and 5 models of care were identified; 4 were specific to AFCs. An online survey with 49 questions included items on: (1) process before visit; (2) process at visit; (3) patient education provided; (4) outreach; and (5) specific clinic information. Clinicians’ advice to patients on self-care items such as: (1) amount of alcohol and (2) caffeine intake; (3) exercise activity; (4) stressful events; (5) “when to go to the emergency department”; and (6) lifestyle changes, were evaluated to assess consistency in practice. There were moderate variances in clinicians’ advice to patients in 5 of 6 self-care items. The 1 item that had 100% consistent practice recommendation was when to go to the emergency department. A guideline-based clinical assessment checklist (CAC) was piloted to obtain feedback on its usability in real-world practice; revisions finalized the “simplified CAC” for AF care encompassing 35 data points with rationale. There was 100% positive feedback on its ability to provide baseline elements in AF care. When validated, a “simplified CAC” can facilitate a standardized clinical assessment tool in clinical practice.  相似文献   
94.
Dental age plays a significant role in forensic dentistry, orthodontics and paediatric dentistry, as well as in general diagnosis and treatment planning. Different methods have been developed to determine dental age. One of the most commonly used methods is Demirjian’s method, which was developed in 1973 from research on a large number of French-Canadian children. It is based on the degree of tooth mineralisation by examining the radiological appearance of the lower mandibular left quadrant. The purpose of this study was to assess the dental age of Omani children using Demirjian's method and evaluate the applicability of the method in dental age estimation for Omani children. The sample consisted of 485 digital panoramic radiographs of children (264 males, 221 females) aged between 4.6?years and 16.5?years, and obtained from the records of the Military Dental Centre in Oman. The data were analysed using SPSS. Paired t-tests, intraclass correlation coefficients (ICC) and difference-against-mean plots were used to compare the dental age calculated by Demirjian's method with chronological age. A single examiner scored the radiographs, and intra-observer reliability was evaluated using Cronbach's alpha on data from rescoring one out of every 20 radiographs. For boys, the mean difference between chronological age and dental age for all age groups was 0.10 (95% CI ?0.03 to 0.24). For girls, the mean difference between chronological age and dental age for all age groups was 0.05 (95% CI ?0.11 to 0.22). Difference-against-mean plots showed no evidence of differential bias by age. For boys, the ICC was 0.896 (95% CI 0.869–0.917); for girls, it was 0.886 (95% CI 0.854–0.911). Difference-against-mean plots for boys (Fig. 1) and girls (Fig. 2) showed some evidence of differential bias by age. In conclusion, the extent of the observed differences was sufficient for doubt to be cast upon the utility of Demirjian’s method for Oman, particularly when it is considered that the method’s most likely application would be in age determination for minors in the workforce.  相似文献   
95.
96.
Poly(ADP-ribose) polymerase is a nucleic enzyme that promotes energy-dependent repair of DNA, thus helping to protect against DNA fragmentation. Overactivation of PARP, for example in the context of apoptosis, may contribute to neuronal cell death. This article briefly reviews claims for PARP inhibitors as agents for the prevention of neuronal cell death, registered in the period 1998 – December 2001. Biological data are sparse in these patents, few claims are backed by in vitro biochemical data and fewer still with in vivo animal model data. The latter have used animal models of ischaemia rather than of neurodegeneration. The place of PARP inhibitors as a clinical therapy to prevent neuronal cell death remains to be determined.  相似文献   
97.
Abstract

Novel aptamer-functionalized polyethylene glycol–polylactic acid (PEG–PLA) (APP) micelles were developed with the objective to target the transferrin receptor on brain endothelial cells. Flurbiprofen, a potential drug for therapeutic management of Alzheimer’s disease (AD), was loaded into the APP micelles using the co-solvent evaporation method. Results indicated that 9.03% (w/w) of flurbiprofen was entrapped in APP with good retention capacity in vitro. Targeting potential of APPs was investigated using the transferring receptor-expressing murine brain endothelial bEND5 cell line. APPs significantly enhanced surface association of micelles to bEND5 cells as quantified by fluorescence spectroscopy. Most importantly, APPs significantly enhanced intracellular flurbiprofen delivery when compared to unmodified micelles. These results suggest that APP micelles may offer an effective strategy to deliver therapeutically effective flurbiprofen concentrations into the brain for AD patients.  相似文献   
98.
It has been suggested that asset-based strategies could provide an opportunity to rethink the approach to public health; however, this may not be a viable option unless there is clear recognition of specific individual assets. Although there has been some consideration of assets within a child health context, this is limited and previous studies have not sought to identify assets from the perspective of the child. This paper reports on a study that drew on an ethnographic approach, using a photo-elicitation method, to facilitate the mapping of children’s internal and external assets from the viewpoint of children themselves. Two primary schools in the South-East of England were used to recruit 20 year five children (aged 9–11 years of age). The participants, 10 boys and 10 girls, were given disposable cameras and asked to take photographs of the activities that they enjoyed. The children’s photographs were used as prompts during individual semi-structured interviews. A constant comparative analysis facilitated the mapping of the children’s assets as the children described them; this process revealed one overall stabilising asset (‘My Family’) as well as eight internal and three external assets. All of the assets are presented within an original model, ‘I’m good’: the children’s asset wheel [CAW], which was developed from the findings. It is suggested that the CAW could complement previous asset-based work to facilitate the rethinking of approaches to the enhancement of children’s public health.  相似文献   
99.
范倩  巩路  魏蔚  孙文闻 《天津医药》2013,41(1):9-11
目的探讨原发性干燥综合征(pSS)并发肺动脉高压(PAH)的发生率、临床特点及筛查方法。方法对61例临床确诊为pSS的患者行彩色多普勒超声心动检查,应用三尖瓣反流速度来估测肺动脉收缩压(PASP),依据PAH诊断标准将其分为PAH组(10例)和非PAH组(51例),收集2组的临床资料、实验室检查、胸CT扫描和超声心动的检测结果并进行比较。结果 (1)61例pSS患者中并发PAH者占16.4%,PAH组中PASP为31~64mmHg,平均(40±9)mmHg,其中4例无任何与PAH相关的临床表现,PAH的发生与患者年龄、性别、病程无关。(2)患者的主要症状为发热、干咳、胸闷或胸痛、心悸、进行性呼吸困难、雷诺现象、胸腔积液和肺间质病变,PAH组雷诺现象、心悸、肺间质病变的发生率高于非PAH组(P<0.05),PAH组的补体C3水平低于非PAH组(P<0.05)。(3)PAH组瓣膜受累达100%,其中2例仅伴有右心系统扩大,3例同时出现左心和右心系统扩大,PAH组左房内径、右房内径、右室内径、肺动脉内径高于非PAH组(P<0.05或P<0.01)。结论 pSS并发PAH并不少见,患者即使无相应临床症状,也应行超声心动筛查,这对PAH的临床早期诊断和治疗十分重要。  相似文献   
100.
《Pharmaceutical biology》2013,51(9):1073-1078
Context: The pharmaceutical alkaloid huperzine A (HupA), currently used in herbal supplements and medicines worldwide, is predominantly sourced from the Chinese lycopod Huperzia serrata (Thunb. ex Murray) Trev. (Lycopodiaceae), which on average contains only 0.08?mg HupA g?1 dry weight, and is experiencing a rapid decline in China due to over-harvesting.

Objective: To find a high-yielding, natural source of HupA and/or the related huperzine B (HupB) that could potentially be used as the starting material in a commercial propagation program.

Materials and methods: We surveyed 17 Huperzia species (15 indigenous to Australia and southeast Asia) for their foliar HupA and HupB concentrations. We also studied intra-specific variation for the huperzines in four species that were available in sufficient numbers, and determined tissue-specific accumulation in larger specimens.

Results: HupA was detected in 11 Australasian and southeast Asian species, with eight also containing HupB, albeit at much lower concentrations. A H. elmeri (Herter) Holub plant from the Philippines had one of the highest HupA concentrations recorded (1.01?mg g?1 dry wt) and it also had the highest HupB content of all plants surveyed (0.34?mg g?1 dry wt). Intra-specific HupA and HupB concentrations were extremely variable, and at the intra-plant level, reproductive strobili were found to accumulate the highest HupA concentrations.

Discussion and conclusion: Select Huperzia species from Australia and southeast Asia have potential as the starting material for establishing commercial HupA plantations, but the high intra-specific variability observed suggests that detailed screening is needed to isolate high huperzine-yielding individuals.  相似文献   
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