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41.
ObjectivesIn this nationwide retrospective study, we analysed species distribution, antimicrobial susceptibility and time to next occurrence of Achromobacter in Danish cystic fibrosis (CF) patients from 2000 to 2011.MethodsThirty-four primary isolates were identified to species level and subjected to antimicrobial susceptibility testing. Effectiveness of early antimicrobial treatment was assessed by a Kaplan–Meier estimation of time to recurrence.ResultsAchromobacter xylosoxidans accounted for 13 (38%) of the isolates, and an unnamed species accounted for 11 (32%) of the isolates. Meropenem, piperacillin–tazobactam and trimethoprim–sulfamethoxazole were highly active against chemotherapy-naïve Achromobacter, while ceftazidime, colistin and tobramycin were judged adequate for inhalation therapy. Fifty-five percent of 25 patients treated with inhaled ceftazidime, colistin, or tobramycin remained free of Achromobacter three years after acquisition, in contrast to 17% of 22 patients who did not receive inhaled antibiotics (P < 0.01).ConclusionsEarly treatment with inhaled antibiotics may prevent or postpone chronic infection with Achromobacter in CF patients.  相似文献   
42.
Two recombinant phenotypic assays for human immunodeficiency virus (HIV) coreceptor usage and an HIV envelope genotypic predictor were employed on a set of clinically derived HIV type 1 (HIV-1) samples in order to evaluate the concordance between measures. Previously genotyped HIV-1 samples derived from antiretroviral-na?ve individuals were tested for coreceptor usage using two independent phenotyping methods. Phenotypes were determined by validated recombinant assays that incorporate either an approximately 2,500-bp ("Trofile" assay) or an approximately 900-bp (TRT assay) fragment of the HIV envelope gp120. Population-based HIV envelope V3 loop sequences ( approximately 105 bp) were derived by automated sequence analysis. Genotypic coreceptor predictions were performed using a support vector machine model trained on a separate genotype-Trofile phenotype data set. HIV coreceptor usage was obtained from both phenotypic assays for 74 samples, with an overall 85.1% concordance. There was no evidence of a difference in sensitivity between the two phenotypic assays. A bioinformatic algorithm based on a support vector machine using HIV V3 genotype data was able to achieve 86.5% and 79.7% concordance with the Trofile and TRT assays, respectively, approaching the degree of agreement between the two phenotype assays. In most cases, the phenotype assays and the bioinformatic approach gave similar results. However, in cases where there were differences in the tropism results, it was not clear which of the assays was "correct." X4 (CXCR4-using) minority species in clinically derived samples likely complicate the interpretation of both phenotypic and genotypic assessments of HIV tropism.  相似文献   
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本研究以宁夏回族自治区为案例,针对村医经济激励水平低下,按项目付费引发不恰当诊治行为,系统内缺乏引导供方提高自身服务效率和质量并促进服务与体系整合协调的经济激励等问题,从供方合理激励的角度出发,对新型农村合作医疗支付制度进行改革设计——以乡村为整体对乡镇卫生院和村卫生室提供的门诊服务实施基于绩效的按人头预付制。随后利用配对整群随机试验设计对改革效果进行评估和检验。研究发现,这一支付制度的实施有效降低了农村基本医疗服务中抗生素的使用率,优化了供方的处方行为,对降低村卫生室的单次门诊费用有一定作用,并且促进服务向村卫生室下沉。本文的政策分析和设计思路及严格的政策评估结果可以为我国支付制度的选择和发展提供政策参考和证据支持。  相似文献   
45.
The identification of FLT3 mutations across a range of the cytogenetic subgroups of AML has opened up the possibility of a targeted therapeutic approach with broad applicability. Four agents are currently in clinical trials, at least 3 of which have both sufficient activity against AML and sufficiently acceptable toxicity profiles to support continued efforts to refine their inclusion into therapeutic regimens for AML. Better understanding of the genetics of inherent and acquired resistance is needed to guide development of second-generation agents. Optimizing the integration of FLT3 inhibitor therapy with chemotherapy has the potential both to decrease toxicity and improve response.  相似文献   
46.

Background

Hospice provides integrative palliative care for advance-staged hepatocellular carcinoma (HCC) patients, but hospice utilization in HCC patients in the USA is not clearly understood.

Aims

We examined hospice use and subsequent clinical course in advance-staged HCC patients.

Methods

We conducted a retrospective study on a national, Veterans Affairs cohort with stage C or D HCC. We evaluated demographics, clinical factors, treatment, and clinical course in relation to hospice use.

Results

We identified 814 patients with advanced HCC, of whom 597 (73.3%) used hospice. Oncologist management consistently predicted hospice use, irrespective of HCC treatment [no treatment: OR 2.25 (1.18–4.3), treatment: OR 1.80 (1.10–2.95)]. Among patients who received HCC treatment, hospice users were less likely to have insurance beyond VA benefits (47.2 vs. 60.0%, p = 0.01). Among patients without HCC treatment, hospice users were older (62.2 [17.2] vs. 60.2 [14.0] years, p = 0.05), white (62.1 vs. 52.9%, p = 0.01), resided in the Southern USA (39.5 vs. 31.8%, p = 0.05), and had a performance score ≥ 3 (41.9 vs. 31.8%, p = 0.01). The median time from hospice entry to death or end of study was 1.05 [2.96] months for stage C and 0.53 [1.18] months for stage D patients.

Conclusions

26.7% advance-staged HCC patients never entered hospice, representing potential missed opportunities for improving end-of-life care. Age, race, location, performance, insurance, and managing specialty can predict hospice use. Differences in managing specialty and short-term hospice use suggest that interventions to optimize early palliative care are necessary.
  相似文献   
47.
Cerebral white matter hyperintensities (WMH) are a consequence of cerebral small vessel disease. Statins have been shown to reduce recurrent stroke among patients with various stroke subtypes, including lacunar stroke, which also arises from small vessel disease. In this study, we investigated the hypothesis that prestroke statin use would reduce the progression of WMH and/or cognitive decline among stroke patients with confluent WMH. Patients (n = 100) were participants of the VITAmins To Prevent Stroke magnetic resonance imaging substudy. All patients had confluent WMH on magnetic resonance imaging at baseline. Eighty-one patients completed the 2-year follow-up. We assessed general cognition and executive function using the mini-mental state examination and Mattis dementia rating scale–initiation/perseveration subscale, respectively. We compared the change in volume of WMH and cognition between prestroke statin use and prestroke nonstatin use groups. We also evaluated the effects of prestroke statin use on incident lacunes and microbleeds. The prestroke statin use group (n = 51) had less WMH volume progression (1.54 ± 4.52 cm3vs 5.01 ± 6.00 cm3, p = 0.02) compared with the prestroke nonstatin use group (n = 30). Multivariate linear regression modeling identified prestroke statin use as an independent predictor of WMH progression (β = –0.31, p = 0.008). Prestroke statin use was also associated with less decline (Mattis dementia rating scale–initiation/perseveration subscale; β = 0.47, p = 0.001). No association was observed with changes in mini-mental state examination scores. There were no between group differences on incident lacunes or incident microbleeds. Prestroke statin use may reduce WMH progression and decline in executive function in stroke patients with confluent WMH.

Electronic supplementary material

The online version of this article (doi:10.1007/s13311-014-0270-5) contains supplementary material, which is available to authorized users.  相似文献   
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Constructing an atlas from a population of brain images is of vital importance to medical image analysis. Especially in neuroscience study, creating a brain atlas is useful for intra‐ and inter‐population comparison. Research on brain atlas construction has attracted great attention in recent years, but the research on pediatric population is still limited, mainly due to the limited availability and the relatively low quality of pediatric magnetic resonance brain images. This article is targeted at creating a high quality representative brain atlas for Chinese pediatric population. To achieve this goal, we have designed a set of preprocessing procedures to improve the image quality and developed an intensity and sulci landmark combined groupwise registration method to align the population of images for atlas construction. As demonstrated in experiments, the newly constructed atlas can better represent the size and shape of brains of Chinese pediatric population, and show better performance in Chinese pediatric brain image analysis compared with other standard atlases. Hum Brain Mapp 35:3880–3892, 2014. © 2014 Wiley Periodicals, Inc .  相似文献   
50.
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