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41.
AF Jorm H Christensen AS Henderson PA Jacomb AE Korten A Mackinnon 《Age and ageing》1996,25(2):126-129
Formal assessment of cognitive decline with cognitive tests can be difficult, requiring either two measurement points or a comparison of 'hold' with 'don't hold' tests. Informant-based assessment provides an alternative approach because informants can adopt a longitudinal perspective and directly rate cognitive change. A study was carried out to assess the validity of informant ratings collected by means of the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE). A community sample of 500 subjects aged 74 or over underwent four cognitive tests on two occasions 3½ years apart. On the second occasion, informants filled out the IQCODE. Subjects rated as having moderate or severe decline were found to have greater change on the cognitive tests. These findings support the validity of informant ratings of cognitive decline. 相似文献
42.
Alpha-adrenoceptor stimulation, lysophosphoglycerides, and lipid peroxidation in reoxygenation induced calcium uptake in rabbit myocardium 总被引:1,自引:0,他引:1
Calcium uptake on reoxygenation of hypoxic cardiac muscle is well documented. Alpha-adrenoceptor stimulation by released catecholamines, lysophosphoglycerides and lipid peroxidation have all been suggested as mediators of this effect. We have measured the uptake of Ca2+ on reoxygenation in the isolated arterially perfused interventricular septum of the rabbit heart. The alpha agonist phenylephrine (1 mumol X litre-1) did not alter calcium uptake, and the presence of either prazosin (1 mumol X litre-1) or phentolamine (10 mumol X litre-1) did not alter the reoxygenation induced Ca2+ uptake. Lysophosphatidylcholine caused an increase in Ca2+ uptake above 8 mumol X litre-1 but also produced a simultaneous increase in the distribution volume of 51Cr-EDTA, an extracellular space marker, indicating loss of membrane integrity. Hydrogen peroxide and cumene hydroperoxide both caused an increased Ca2+ uptake, but no disruption of the cell membrane; the effect on Ca2+ uptake could be inhibited by Ni2+ ions. Alpha adrenergic stimulation and lysophosphoglycerides do not appear to be key to Ca2+ uptake on reoxygenation, but lipid peroxidation of the sarcolemma is a possible mechanism. 相似文献
43.
44.
目的 分析MRI形态学半定量评分对新生儿细菌性脑膜炎出院结局的评估价值。方法 收集复旦大学附属儿科医院2011年7月至2013年12月NICU收治的出院诊断为新生儿细菌性脑膜炎的病例,采用基于大脑损伤MRI形态学分析的半定量评分,对头颅MRI图像进行回顾性分析。MRI形态学评价包括脑室扩大、脑室旁白质容积丢失、脑白质囊性病灶、内囊后肢髓鞘化异常、皮质信号异常、颅内脑外间隙异常、基底节信号异常、脑白质非囊性信号异常、脑室内出血、脑室积脓、脑膜异常强化、室管膜异常强化和脑脓肿。将上述13项评分归纳为脑白质异常(WMA)、脑灰质异常(GMA)和非脑实质异常(NPA)。同时采集患儿出生孕周、发病时间、MRI检查时间、发病至MRI检查间隔时间和出院结局。按照出生孕周分为早产儿组和足月儿组,再按照出院结局分为预后良好和预后不良亚组,在各组内比较亚组之间时间因素、MRI单项评分和综合评分的差异。结果 63例新生儿细菌性脑膜炎病例进入分析(早产儿组18例,足月儿组45例)。MRI单项评分构成预后良好和预后不良亚组间差异有统计学意义的指标:早产儿组中有脑室扩大(P=0.012)和脑室旁白质容积丢失(P=0.004);足月儿组有脑室扩大(P=0.002)、脑室旁容积丢失(P=0.040)、颅内脑外间隙异常(P=0.005)和脑室内出血(P=0.038)。MRI综合评分中,早产儿组WMA评分(P=0.001)和NPA评分(P=0.039)、足月儿组NPA评分(P=0.018)在预后不良和预后良好亚组之间分布差异有统计学意义。足月儿组和早产儿组内不同预后亚组的各时间因素差异未发现统计学意义或临床意义。结论 新生儿细菌性脑膜炎MRI脑室扩大和脑室旁白质容积丢失预示早产儿出院不良结局;脑室扩大、脑室旁白质容积丢失、颅内脑外间隙异常和脑室内出血预示足月儿出院不良结局。WMA评分高预示早产儿出院不良结局,NPA评分高预示早产儿和足月儿出院不良结局。 相似文献
45.
Successful hematopoietic cell transplantation in a patient with X‐linked agammaglobulinemia and acute myeloid leukemia 下载免费PDF全文
46.
Morgan R. Bobb Azeemuddin Ahmed MD MBA Paul Van Heukelom MD Rachel Tranter MPAS PA‐C Karisa K. Harland PhD MPH Brady M. Firth PhD MA Randy Fry MBA Katherine Schneider MSN RN CEN Kathryn K. Dierks DO Sarah L. Miller MD Nicholas M. Mohr MD MS 《Academic emergency medicine》2018,25(7):795-803
Objective
The objective of this study was to determine specific provider practices associated with high provider efficiency in community emergency departments (EDs).Methods
A mixed‐methods study design was utilized to identify key behaviors associated with efficiency. Stage 1 was a convenience sample of 16 participants (ED medical directors, nurses, advanced practice providers, and physicians) identified provider efficiency behaviors during semistructured interviews. Ninety‐nine behaviors were identified and distilled by a group of three ED clinicians into 18 themes. Stage 2 was an observational study of 35 providers was performed in four (30,000‐ to 55,000‐visit) community EDs during two 4‐hour periods and recorded in minute‐by‐minute observation logs. In Stage 3, each behavior or practice from Stage 1 was assigned a score within each observation period. Behaviors were tested for association with provider efficiency (relative value units/hour) using linear univariate generalized estimating equations with an identity link, clustered on ED site.Results
Five ED provider practices were found to be positively associated with efficiency: average patient load, using name of team member, conversations with health care team, visits to patient rooms, and running the board. Two behaviors, “inefficiency practices,” demonstrated significant negative correlations: non–work‐related tasks and documentation on patients no longer in the ED.Conclusions
Average patient load, running the board, conversations with team member, and using names of team members are associated with enhanced provider productivity. Identification of behaviors associated with efficiency can be utilized by medical directors, clinicians, and trainees to improve personal efficiency or counsel team members.47.
48.
Moon JC De Arenaza DP Elkington AG Taneja AK John AS Wang D Janardhanan R Senior R Lahiri A Poole-Wilson PA Pennell DJ 《Journal of the American College of Cardiology》2004,44(3):554-560
OBJECTIVES: The purpose of this study was to determine the pathologic basis of Q-wave (QW) and non-Q-wave (NQW) myocardial infarction (MI). BACKGROUND: The QW/NQW distinction remains in wide clinical use but the meaning of the difference remains controversial. We hypothesized that measurement of total MI size and transmural extent by late gadolinium enhancement cardiovascular magnetic resonance (CMR) would identify the pathologic basis of QWs. METHODS: A total of 100 consecutive patients with documented previous MI had electrocardiogram and CMR on the same day. Patients with acute MI within seven days were excluded. Left ventricular function and the size and transmural extent of MI were quantified in the three major arterial territories and correlated with the presence of QW. RESULTS: Subendocardial MI showed QW in 28%. Transmural MI showed NQW in 29%. Of all MIs, 48% were at some point transmural, and 99% of these were at some point non-transmural. As MI size and number of transmural segments increased, the probability of QW increased (anterior: total size chi-square = 53, p < 0.0001, transmural extent chi-square = 36, p < 0.0001; inferior: total size chi-square = 16, p = 0.001, transmural extent chi-square = 10, p = 0.001). These findings did not hold for lateral MI. In a multivariate model, the transmural extent of MI was not an independent predictor of QW when total size of MI was removed. The QW/NQW classification was a good test for size of MI (area under receiver operating characteristic curve: anterior 0.90, inferior 0.77). CONCLUSIONS: The QW/NQW distinction is useful, but it is determined by the total size rather than transmural extent of underlying MI. 相似文献
49.
Central haemodynamics and regional blood flow were studied comprehensively in conscious New Zealand White rabbits before and during the development of chronic low output cardiac failure produced by administration of the anticancer agent adriamycin. After eight weeks of adriamycin treatment, cardiac index fell from 326(40 to 225(56) ml.min-1.kg-1. This was accompanied by an increase in heart rate and total peripheral resistance but no change in mean systemic blood pressure. Myocardial function was shown to be depressed by the measurement of Frank-Starling curves, the slopes of which were appreciably flatter in adriamycin treated rabbits. Regional blood flow (measured by the radioactive microsphere technique) was redistributed. There were decreases in renal, splenic, small gut, and skeletal muscle blood flow, whereas myocardial and cerebral blood flow were unchanged. There was an increase in total body exchangeable sodium, indicating some salt and water retention. Systemic toxic effects of adriamycin could be limited by treating the animals for eight weeks with adriamycin and then allowing a two week recovery period before haemodynamic study. This would appear to be the optimal dosage schedule. 相似文献
50.
STUDY OBJECTIVE--The aim was to identify the role of the endothelium in mediating the responses to acetylcholine in the rabbit coronary artery, and to determine whether alpha or beta adrenergic stimulation may cause relaxation via endothelial receptors in the coronary arteries of this species. DESIGN--Responses to acetylcholine and adrenoceptor agonists were compared in isolated ring preparations with and without endothelium. The adrenoceptor agonists were examined in the presence of phentolamine or propranolol to block alpha and beta adrenoceptors, respectively. EXPERIMENTAL MATERIAL--30 New Zealand white rabbits (2.3-3.4 kg) were killed by an overdose of barbiturate and exsanguination, and the left epicardial coronary artery was dissected free. Ring preparations were suspended in organ baths under isometric tension and, where required, the tone of the preparations was raised by KC1. MEASUREMENTS AND MAIN RESULTS--Concentrations of acetylcholine up to 10(-6) mol.litre-1 produced dose dependent relaxation of the preparations with endothelium intact, but no relaxation in preparations denuded of endothelium. At higher concentrations, a marked vasoconstrictor response was seen in all preparations regardless of the presence of endothelium. At basal tone, acetylcholine produced vasoconstriction which reached a maximum of 1.0 (SEM 0.14)g tension in preparations with endothelium and 1.74(0.27) g tension in those without endothelium (p less than 0.05). In coronary arteries pretreated with 50 mumol.litre-1 phenoxybenzamine to block alpha adrenoceptors, noradrenaline, isoprenaline, and salbutamol produced dose dependent relaxation of the preparations; this was unaffected by the absence of endothelium. In vessels not pretreated with phenoxybenzamine, propranolol inhibited the relaxation to noradrenaline and isoprenaline but again there was no difference between vessels with and without endothelium. CONCLUSIONS--In the rabbit isolated epicardial coronary artery, acetylcholine produces an endothelium dependent relaxant response over a limited concentration range; a vasoconstrictor response via smooth muscle dominates at higher concentrations. beta Adrenoceptors mediating relaxation are present on the smooth muscle, but there was no evidence for either alpha or beta adrenoceptor mediated responses via the endothelium. Important differences with coronary arteries from other species are discussed. 相似文献