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991.
Christian J Schrandt S M Shams Kazmi Theresa A Jones Andrew K Dunn 《Journal of cerebral blood flow and metabolism》2015,35(6):933-942
Monitoring the progression of the vascular structure and cerebral blood flow (CBF) after brain injury is vital to understand the neurovascular recovery process. Multiexposure speckle imaging (MESI) provides a quantitatively accurate technique for chronically measuring the postocclusion CBF perfusion of the infarct and peri-infarct regions in rodent stroke models, while multiphoton microscopy offers direct visualization of the microvascular structure. In this paper, we present imaging outcomes extending 35 days after photo-thrombotic occlusion, tracking the progression of the vasculature throughout this period. We compare MESI flow estimates within the unresolvable parenchyma with subsurface microvascular volume fractions taken with two-photon microscopy in the same regions to assess how the vascular density influences the surface-integrated MESI flow values. The MESI flow measurements and volume fractions are shown to have high correlations (r=0.90) within areas of recovering vasculature in the peri-infarct region. We also observe vascular reorientation occurring within the microvascular structure throughout the 35-day postocclusion period. With the combination of a chronic mouse model and relatively noninvasive optical imaging techniques, we present an imaging protocol for monitoring long-term vascular progression after photo-thrombotic occlusion with the potential to test the efficacy of rehabilitation and pharmacological therapies. 相似文献
992.
V Hendrick L Altshuler A Wertheimer W A Dunn 《The American journal of psychiatry》2001,158(12):2089-2090
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Annie YS Lau Adam G Dunn Nathan Mortimer Aideen Gallagher Judith Proudfoot Annie Andrews Siaw-Teng Liaw Jacinta Crimmins Ama?l Arguel Enrico Coiera 《Journal of medical Internet research》2013,15(9)
Background
Personally controlled health management systems (PCHMSs) contain a bundle of features to help patients and consumers manage their health. However, it is unclear how consumers actually use a PCHMS in their everyday settings.Objective
To conduct an empirical analysis of how consumers used the social (forum and poll) and self-reflective (diary and personal health record [PHR]) features of a Web-based PCHMS designed to support their physical and emotional well-being.Methods
A single-group pre/post-test online prospective study was conducted to measure use of a Web-based PCHMS for physical and emotional well-being needs during a university academic semester. The PCHMS integrated an untethered PHR with social forums, polls, a diary, and online messaging links with a health service provider. Well-being journeys additionally provided information to encourage engagement with clinicians and health services. A total of 1985 students and staff aged 18 and above with access to the Internet were recruited online, of which 709 were eligible for analysis. Participants’ self-reported well-being, health status, health service utilization, and help-seeking behaviors were compared using chi-square, McNemar’s test, and Student’s t test. Social networks were constructed to examine the online forum communication patterns among consumers and clinicians.Results
The two PCHMS features that were used most frequently and considered most useful and engaging were the social features (ie, the poll and forum). More than 30% (213/709) of participants who sought well-being assistance during the study indicated that other people had influenced their decision to seek help (54.4%, 386/709 sought assistance for physical well-being; 31.7%, 225/709 for emotional well-being). Although the prevalence of using a self-reflective feature (diary or PHR) was not as high (diary: 8.6%, 61/709; PHR: 15.0%, 106/709), the proportion of participants who visited a health care professional during the study was more than 20% greater in the group that did use a self-reflective feature (diary: P=.03; PHR: P<.001).Conclusions
There was variation in the degree to which consumers used social and self-reflective PCHMS features but both were significantly associated with increased help-seeking behaviors and health service utilization. A PCHMS should combine both self-reflective as well as socially driven components to most effectively influence consumers’ help-seeking behaviors. 相似文献997.
Chakraborty R Smith CJ Dunn D Green H Duong T Doerholt K Riordon A Lyall H Tookey P Butler K Sabin CA Gibb D Pillay D;Collaborative HIV Paediatric Study;UK Collaborative Group on HIV Drug Resistance 《The Pediatric infectious disease journal》2008,27(5):457-459
We reviewed HIV-1 genotypes from 200 of 979 (20%) HIV-infected children in the U.K. Collaborative HIV in Pediatric Study (CHIPS) cohort (343 resistance tests). Three of 44 samples had major primary resistance mutations before antiretroviral therapy. Three-class resistance was noted in 42 samples (14.1%). Our study also highlighted underutilization of testing and the need for prompt genotyping after drug discontinuation which may have lead to an underestimation of HIV-1 resistance. 相似文献
998.
The biopsychosocial model is increasingly accepted in low back pain (LBP) research and clinical practice. In order to assess the role of psychological factors in the development and persistence of pain, a wide array of measures has been developed. Yet there is likely to be considerable conceptual overlap between such measures, and consequently, a lack of clarity about the importance of psychological factors. The aims of this study were to investigate the extent of any such overlap. An observational cohort study of 1591 LBP patients consulting in primary care completed data on a range of psychological instruments. Exploratory and confirmatory factor analyses (EFA and CFA, respectively) were carried out at the subscale level (n = 20) to investigate factor structure. The influences of the derived factors on clinical outcomes (pain intensity and self-reported disability) were then tested using linear regression. EFA yielded 4 factors, termed “Pain-related distress,” “Cognitive coping,” “Causal beliefs,” and “Perceptions of the future,” which accounted for 65.5% of the variance. CFA confirmed the validity of these factors models. The pain-related distress factor was found to have the strongest association to LBP patients’ outcomes, accounting for 34.6% of the variance in pain intensity, and 51.1% of the variance in disability. Results confirmed that considerable overlap exists in psychological measures commonly used in LBP research. Most measures tap into patients’ emotional distress. These findings help us to understand how psychological constructs relate together; implications for future research and clinical practice are discussed. 相似文献
999.
Matthew M. Lander Nicole Kunz Elizabeth Dunn Andrew D. Althouse Kathy Lockard Michael A. Shullo Robert L. Kormos Jeffrey J. Teuteberg 《Journal of cardiac failure》2018,24(11):746-752
Background
Driveline infection (DLI) is a cause of morbidity and mortality in patients with continuous-flow left ventricular assist devices (CF-LVADs). We hypothesized that an alternate dressing protocol would decrease the rate of DLIs.Methods and Results
A retrospective review of CF-LVAD implants at a single institution from January 2010 to October 2015 was conducted. Patients were divided into implants before (group 1) and after (group 2) the introduction of the new protocol on September 1, 2012. Patients were followed until death, transplantation, change in dressing type, or 2 years. 153 patients were included: 61 in group 1 and 92 in group 2. Group 1 had fewer HVADs than group 2 (27.9% vs 71.7%; P < .001) and more destination therapy, although the latter was not statistically significant (50.8% vs 34.8%; P?=?.118). At 24 months, the freedom from DLI was 53% in group 1 and 89% in group 2 (P?=?.01). Group 1 had a significantly greater risk of DLI than group 2 (incident rate ratio 3.18, 95% confidence interval 1.23–8.18; P?=?.016).Conclusions
Dramatic improvement in freedom from DLI at 2 years was achieved with a new driveline dressing protocol. This demonstrates that DLI rates can be improved with alternate percutaneous site care techniques in CF-LVAD patients. 相似文献1000.
Joan Dolce Dunn 《International journal of nursing knowledge》1998,9(Z2):136-143
PURPOSE. The purpose of the study was to develop a scale to calculate college students' powerlessness regarding health service barriers (PHSB). METHODS. Scale items were generated to represent two domains of interest: powerlessness and college students' powerlessness regarding health service barriers. The final 20-item instrument was subjected to multiple measures of validity with college students and panels of nurse experts in the area of nursing diagnosis. Reliability was assessed by two samples (n = 92 and n = 33) of college-age students. A final administration was conducted with 197 college students. FINDINGS. The PHSB scale was determined to be an accurate and consistent measure. CONCLUSIONS. This instrument will provide a reliable and valid measure to conduct research. 相似文献