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31.
32.
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   
33.
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   
34.
35.

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.
  相似文献   
36.
Cassileth  PA; Suholet  D; Cooper  RA 《Blood》1981,58(2):237-243
The HL-60 leukemia cell line derived from a human acute promyelocytic leukemia is stimulated to differentiate into macrophages within 24-28 hr after exposure to the phorbol ester, 12-O-tetradecanoylphorbol-13- acetate (TPA). We studied early alterations (within 90 min of exposure to TPA) in phosphatidylcholine metabolism in HL-60 cells and found that phosphatidylcholine synthesis by methylation is phosphatidylethanolamine was inhibited in a dose-dependent fashion. In contrast, synthesis of phosphatidylcholine from endogenous choline was enhanced and correlated inversely with the degree of inhibition of the methylation pathway. Phorbol ester congeners of TPA caused similar alterations in phosphatidylcholine metabolism in direct relationship to their capacity to induce differentiation in HL-60 cells. Perturbation of phosphatidylcholine metabolism is an early membrane even in TPA- induced HL-60 cell differentiation.  相似文献   
37.
We recently reported a significant increase in the frequency of carriers of grey zone (GZ) alleles of FMR1 gene in Australian males with Parkinson's disease (PD) from Victoria and Tasmania. Here, we report data comparing an independent sample of 817 PD patients from Queensland to 1078 consecutive Australian male newborns from Victoria. We confirmed the earlier finding by observing a significant excess of GZ alleles in PD (4.8%) compared to controls (1.5%). Although both studies provided evidence in support of an association between GZ‐carrier status and increased risk for parkinsonism, the existing evidence in the literature from screening studies remains equivocal and we discuss the need for alternative approaches to resolve the issue.  相似文献   
38.
Global cerebral hypoperfusion may be involved in the aetiology of brain atrophy; however, long-term longitudinal studies on this relationship are lacking. We examined whether reduced cerebral blood flow was associated with greater progression of brain atrophy. Data of 1165 patients (61 ± 10 years) from the SMART-MR study, a prospective cohort study of patients with arterial disease, were used of whom 689 participated after 4 years and 297 again after 12 years. Attrition was substantial. Total brain volume and total cerebral blood flow were obtained from magnetic resonance imaging scans and expressed as brain parenchymal fraction (BPF) and parenchymal cerebral blood flow (pCBF). Mean decrease in BPF per year was 0.22% total intracranial volume (95% CI: –0.23 to –0.21). Mean decrease in pCBF per year was 0.24 ml/min per 100 ml brain volume (95% CI: –0.29 to –0.20). Using linear mixed models, lower pCBF at baseline was associated with a greater decrease in BPF over time (p =0.01). Lower baseline BPF, however, was not associated with a greater decrease in pCBF (p =0.43). These findings indicate that reduced cerebral blood flow is associated with greater progression of brain atrophy and provide further support for a role of cerebral blood flow in the process of neurodegeneration.  相似文献   
39.

Cerebrovascular autoregulation (CA) is often impaired following traumatic brain injury. Established technologies and metrics used to assess CA are invasive and conducive for measurement, but not for continuous monitoring. We developed a trans-ocular brain impedance (TOBI) method that may provide non-invasive and continuous indices to assess CA. In this study, we monitored impedance metrics such as respiratory-induced impedance amplitude changes (dz) as well as a novel impedance index (DZx), which is a moving Pearson correlation between mean arterial pressure (MAP) and dz. Yorkshire swine were instrumented to continuously record ICP, MAP, and cerebral blood flow (CBF). TOBI was recorded by placement of standard ECG electrodes on closed eyelids and connected to a data acquisition system. MAP, ICP and CBF were manipulated utilizing an intravenous vasopressor challenge. TOBI indices (dz and DZx) were compared to the hemodynamic indicators as well as pressure reactivity index (PRx). During the vasopressor challenge, dz was highly correlated with ICP, CPP, and CBF (r?=??<?? 0.49, p?<?0.0001). ICP, CPP, and CBF had a mean percent increase (standard deviation) from baseline of 29(23.2)%, 70(25)%, and 37(72.6)% respectively while dz decreased by 31(15.6)%. Receiver operator curve test showed high predictive performance of DZx when compared to PRx with area under the curve above 0.86, with high sensitivity and specificity. Impedance indices appear to track changes in PRx and hemodynamics that affect cerebral autoregulation. TOBI may be a suitable less invasive surrogate to PRx and capable of tracking cerebral autoregulation.

  相似文献   
40.
Antigenic modulation is one of many factors determining the effectiveness of monoclonal antibody (MoAb)-mediated therapy. To select the isotype of a CD19 MoAb most suitable for radioimmunotherapy of patients with B-cell malignancies, we studied the influence of MoAb isotype on modulation, after binding of the MoAb to different cell-line cells. The CD19-IgG1 MoAb was found to induce modulation of CD19 antigens on Daudi cell line cells more rapidly than did its IgG2a switch variant. We provide evidence that this difference in modulation rate is caused by the expression of Fc gamma receptor II (Fc gamma RII) on these cells. Experiments aimed at elucidating the mechanism of Fc gamma RII involvement in modulation induction by CD19-IgG1 showed that Fc gamma RII did not comodulate with CD19 MoAbs. However, cocrosslinking of CD19 and Fc gamma RII with CD19-IgG1 MoAb resulted in enhanced calcium mobilization in Daudi cells. This increased signal induction accompanies the enhanced capping and subsequent modulation of CD19 antigens. Because Fc gamma RII is expressed in varying densities on malignant B cells in all differentiation stages, our results have implications for the MoAb isotype most suitable for use in MoAb-based therapy of patients with B-cell malignancies.  相似文献   
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