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41.
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   
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43.

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   
44.
Objective To develop expeditiously a pragmatic, modular, and extensible software framework for understanding and improving healthcare value (costs relative to outcomes).Materials and methods In 2012, a multidisciplinary team was assembled by the leadership of the University of Utah Health Sciences Center and charged with rapidly developing a pragmatic and actionable analytics framework for understanding and enhancing healthcare value. Based on an analysis of relevant prior work, a value analytics framework known as Value Driven Outcomes (VDO) was developed using an agile methodology. Evaluation consisted of measurement against project objectives, including implementation timeliness, system performance, completeness, accuracy, extensibility, adoption, satisfaction, and the ability to support value improvement.Results A modular, extensible framework was developed to allocate clinical care costs to individual patient encounters. For example, labor costs in a hospital unit are allocated to patients based on the hours they spent in the unit; actual medication acquisition costs are allocated to patients based on utilization; and radiology costs are allocated based on the minutes required for study performance. Relevant process and outcome measures are also available. A visualization layer facilitates the identification of value improvement opportunities, such as high-volume, high-cost case types with high variability in costs across providers. Initial implementation was completed within 6 months, and all project objectives were fulfilled. The framework has been improved iteratively and is now a foundational tool for delivering high-value care.Conclusions The framework described can be expeditiously implemented to provide a pragmatic, modular, and extensible approach to understanding and improving healthcare value.  相似文献   
45.
BACKGROUND & AIMS: We report a novel approach to study biliary water, bile acid, and HCO(3)(-) transport: the microperfusion of intrahepatic bile duct units (IBDUs) isolated from normal rat liver. METHODS: To study water transport, IBDUs were perfused in vitro with a membrane-impermeant fluorescent volume marker, fluorescein sulfonate; net water movement (J(v)) and osmotic water permeability (P(f)) were then calculated. To study solute transport, IBDUs were perfused with taurocholic acid (TCA) and bile acid uptake was calculated from the concentrations of TCA in the perfused and collected solutions. To study ion transport, IBDUs were perfused with the cell-impermeant pH-sensitive dye BCECF dextran; luminal pH was determined from fluorescence excitation ratios. RESULTS: When inward (secretory) or outward (absorptive) osmotic gradients were established across IBDUs, water movement was observed from bath to lumen (i.e., secretion) and from lumen to bath (i.e., absorption). The perfused IBDUs absorbed TCA in a saturable, sodium-dependent manner; in addition, TCA absorption was blocked in a dose-dependent fashion by S0960, a specific inhibitor of the Na(+)/bile acid cotransporter. Addition of forskolin to HCO(3)(-)-containing (but not HCO(3)(-)-free) bath buffer resulted in lumen alkalinization reflecting HCO(3)(-) transport into the lumen of perfused IBDUs. CONCLUSIONS: The results provide direct functional evidence that intrahepatic bile ducts both secrete and absorb water in response to osmotic gradients, actively absorb bile acid, and transport HCO(3)(-).  相似文献   
46.
OBJECTIVES: Treatment with inhaled corticosteroids reduces bronchial hyperresponsiveness and relieves airways obstruction in patients with asthma. Up to now, it is unknown whether initial improvements are maintained over a long period of time. Therefore, we assessed whether initial improvements in FEV(1), provocative concentration of histamine causing a 20% fall in FEV(1) (PC(20)), and peak expiratory flow (PEF) persist with a constant dose of inhaled corticosteroids. Furthermore, we investigated whether FEV(1), PC(20), PEF indexes, and symptom scores improve after increasing the dose of inhaled corticosteroids in patients who did not respond sufficiently to treatment with beclomethasone dipropionate (BDP), 800 microg/d. METHODS: Sixty-eight patients with bronchial hyperresponsiveness and airways obstruction completed a previous study on 3 years of treatment with terbutaline, 500 microg qid, and BDP, 200 microg qid. Fifty-eight of these patients participated in the current extension of another 2.5 years of follow-up. Every 6 months, FEV(1) and PC(20) were measured. Five patients dropped out of the study, one for pulmonary reasons. Forty-four patients continued treatment with BDP, 800 microg/d (BDP-800 group), and 9 patients received a higher dose of BDP (500 microg tid; BDP-1,500 group) after the first 3 years because of a rapid decline in FEV(1) (> 50 mL/yr) despite BDP treatment during the previous study period. RESULTS: After the initial improvement, the mean slope of individual regression lines for FEV(1), PC(20), and morning PEF were - 28 mL/yr, - 0.01 doubling concentrations per year, and 0.6 L/min/yr, respectively, in the BDP-800 group. In the BDP-1,500 group, there were no statistically significant improvements in FEV(1), PC(20), PEF indexes, and symptom scores after increasing the dose of BDP. CONCLUSIONS: We conclude that initial improvements in FEV(1), PC(20), and PEF are well preserved over 5 years in patients with obstructive airways diseases who are treated with terbutaline and BDP. In the patients who responded sufficiently to 800 microg/d of BDP, there was no accelerated decline in FEV(1) compared with the general population. Increasing the dose of BDP in a small group of patients with an accelerated fall in FEV(1) (initially treated with a moderate dose of BDP) resulted in no significant improvement in FEV(1), PC(20), PEF indexes, and symptom scores.  相似文献   
47.
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   
48.
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   
49.
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   
50.
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