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排序方式: 共有281条查询结果,搜索用时 15 毫秒
1.
Investigation of optical attenuation imaging using optical coherence tomography for monitoring of scars undergoing fractional laser treatment 下载免费PDF全文
Shaghayegh Es'haghian Peijun Gong Lixin Chin Karl‐Anton Harms Alexandra Murray Suzanne Rea Brendan F. Kennedy Fiona M. Wood David D. Sampson Robert A. McLaughlin 《Journal of biophotonics》2017,10(4):511-522
We demonstrate the use of the near‐infrared attenuation coefficient, measured using optical coherence tomography (OCT), in longitudinal assessment of hypertrophic burn scars undergoing fractional laser treatment. The measurement method incorporates blood vessel detection by speckle decorrelation and masking, and a robust regression estimator to produce 2D en face parametric images of the attenuation coefficient of the dermis. Through reliable co‐location of the field of view across pre‐ and post‐treatment imaging sessions, the study was able to quantify changes in the attenuation coefficient of the dermis over a period of ~20 weeks in seven patients. Minimal variation was observed in the mean attenuation coefficient of normal skin and control (untreated) mature scars, as expected. However, a significant decrease (13 ± 5%, mean ± standard deviation) was observed in the treated mature scars, resulting in a greater distinction from normal skin in response to localized damage from the laser treatment. By contrast, we observed an increase in the mean attenuation coefficient of treated (31 ± 27%) and control (27 ± 20%) immature scars, with numerical values incrementally approaching normal skin as the healing progressed. This pilot study supports conducting a more extensive investigation of OCT attenuation imaging for quantitative longitudinal monitoring of scars.
2.
Longleaf pine (Pinus palustris) savanna is a biodiverse ecosystem native to the southeastern United States. Due to fire suppression and timber harvest, longleaf pine has declined to 3% of its original range. The extant forest provides habitat for many threatened and endangered species, including the endangered Red-cockaded Woodpecker (Picoides borealis; RCW), a cavity-nesting bird that co-evolved with fire-maintained forest, resulting in savanna-like old-growth forest as the bird’s preferred habitat. Our study site, the Oakmulgee Ranger District of the Talladega National Forest, harbors the largest RCW population in Alabama and is managed with an emphasis on RCW conservation. The United States Forest Service (USFS) also manages the Oakmulgee for uses such as wildlife conservation, recreation, and timber harvest. Despite efforts to restore RCW habitat and install artificial cavities in the Oakmulgee, the number of RCW groups has not exceeded 123, although the Recovery Plan objective is 394 groups. Our project was motivated by the USFS expressing interest in determining why the RCW population has not exceeded 123 groups. We proposed using structured decision making (SDM) with the USFS and other stakeholders to address this problem. Our goals were to explicitly define management objectives, build a Bayesian belief network with a model of how decision alternatives are believed to affect management objectives, and use a sensitivity analysis to determine the part of the model to which RCW population growth was most sensitive. Therefore, results from the analysis were expected to give insights into 1) ecological factors limiting RCW population growth, 2) how management can overcome these limits, plus 3) the relative expected ability of different decision alternatives to satisfy multiple objectives in addition to increasing RCW group number. We held four SDM workshops with representatives from the USFS, the Animal and Plant Health Inspection Service, the Longleaf Alliance, the Birmingham Audubon Society, and local residents. Stakeholder objectives consisted of maximizing the following: RCW group number, forest health, recreational enjoyment, community economic health, and aesthetics. Cavity insert installation had the greatest probability of increasing the number of RCW groups. The number of RCW groups was most affected by cavity availability, adult survival, reproductive output, food availability, and herbaceous understory. Prescribed burning was most likely to meet the combination of stakeholder objectives, followed by midstory removal. Our findings suggest that cavity installation efforts may need to be increased in the Oakmulgee to increase RCW group number. Also it could be beneficial to investigate how RCWs select cavity tree locations with the goal of increasing the chance that RCWs use artificial cavities to form new groups. The Bayesian belief network provided insights into factors limiting RCW population growth and how management can overcome these limits. The Bayesian belief network also can be used to prioritize management methods in the Oakmulgee given stakeholder objectives and time constraints. 相似文献
3.
Relevance of Global Forest Change Data Set to Local Conservation: Case Study of Forest Degradation in Masoala National Park,Madagascar 下载免费PDF全文
Zuzana Burivalova Martin R. Bauert Sonja Hassold Nandinanjakana T. Fatroandrianjafinonjasolomiovazo Lian Pin Koh 《Biotropica》2015,47(2):267-274
A global data set on forest cover change was recently published and made freely available for use (Hansen et al. 2013. Science 342: 850–853). Although this data set has been criticized for inaccuracies in distinguishing vegetation types at the local scale, it remains a valuable source of forest cover information for areas where local data is severely lacking. Masoala National Park, in northeastern Madagascar, is an example of a region for which very little spatially explicit forest cover information is available. Yet, this extremely diverse tropical humid forest is undergoing a dramatic rate of forest degradation and deforestation through illegal selective logging of rosewood and ebony, slash‐and‐burn agriculture, and damage due to cyclones. All of these processes result in relatively diffuse and small‐scale changes in forest cover. In this paper, we examine to what extent Hansen et al.'s global forest change data set captures forest loss within Masoala National Park by comparing its performance to a locally calibrated, object‐oriented classification approach. We verify both types of classification with substantial ground truthing. We find that both the global and local classifications perform reasonably well in detecting small‐scale slash‐and‐burn agriculture, but neither performs adequately in detecting selective logging. We conclude that since the use of the global forest change data set requires very little technical and financial investment, and performs almost as well as the more resource‐demanding, locally calibrated classification, it may be advantageous to use the global forest change data set even for local conservation purposes. 相似文献
4.
PurposeTo compare computed tomography (CT) image properties between a vendor-independent image-based noise reduction technique, Image-space Noise Reduction (iNoir) and a hybrid-type iterative reconstruction technique, Adaptive Statistical Iterative Reconstruction (ASIR).MethodsA cylindrical water phantom, corresponding to pediatric body size, containing soft-tissue-equivalent rod and 12-mg iodine/ml rod was scanned at size-specific dose estimates of 8.4 and 16.7 mGy. For assessments of image quality and noise texture change, task-based system performance function (SPF) and peak frequency difference (PFD) were compared, respectively, among filtered back projection (FBP), IR image with 50%-blending rate (50%ASIR), 100%ASIR, 50%iNoir, and 100%iNoir. Human observer test for pediatric CT images was performed by radiologists.ResultsFor the soft-tissue contrast, SPF2 of 100%iNoir was the highest. The average SPF2 between 0.1 and 0.5 cycles/mm for 100%iNoir increased by approximately 70% compared with FBP, while ASIR indicted slight increases in the frequency region of >0.2 cycles/mm. For the iodine contrast, 100%iNoir indicated highest values at the spatial frequencies corresponding pediatric artery diameters. The PFDs of iNoir were negligible and lower than that of ASIR. The results of human observer test supported results of SPF2 and PFD.ConclusionsCompared with ASIR, iNoir provided better image quality for pediatric abdominal CT without compromising noise texture change. 相似文献
5.
A HPLC method has been developed to measure phosphatidylcholine (PC) containing reactive carbonyl functions in the sn-acyl residue in order to study processes in which such reactive carbonyls can be formed due to e.g. oxidative fragmentation. The method has been applied to determine PC-bound carbonyls as 2, 4-dinitrophenylhydrazones (DNPH) in plasma of burn patients. Plasma from healthy volunteers served as controls. Additionally, in vitro oxidation experiments (A: plasma, buffer diluted; B: plasma + iron-EDTA complex and C: plasma + iron-EDTA complex + H2O2) have been performed to obtain and to identify 2, 4-dinitrophenylhydrazine derivatizable carbonyl functions in plasma PC. Both, the PC-aldehydes and PC-aldehyde DNPH derivatives were cleavable with phospholipase C. Quantification was based on thin-layer chromatography purified soybean phosphatidylcholine, which was identically oxidized and derivatized as the plasma lipids in vitro. 相似文献
6.
目的 研究小儿腹泻病继发乳糖不耐受的年龄、病因及乳糖酶治疗继发乳糖不耐受的效果.方法 对382例腹泻继发乳糖不耐受患儿进行年龄、病因分析,同时将患儿分成治疗及对照两组,分析乳糖酶的疗效.结果 小儿腹泻继发乳糖不耐受以婴幼儿多见,轮状病毒感染是继发乳糖不耐受的主要病因,乳糖酶治疗继发乳糖不耐受疗效显著.结论 婴幼儿腹泻常规给予乳糖酶可以缩短病程,减少治疗费用,患儿及家长易于接受. 相似文献
7.
目的探讨通过随访观察金双歧辅助治疗小儿扁桃体炎患儿的远期效果。方法选取2013年1月至2014年7月在本院儿科住院诊断为扁桃体炎患儿300例,采用随机数字表法,按入院先后顺序分为对照组和观察组,对照组常规给予抗生素(包括抗病毒药)和(或)对症治疗;观察组在对照组治疗的基础上,给予金双歧口服辅助治疗,出院后继续服用金双歧4周;两组患儿分别在出院后1个月、2个月、3个月均进行电话随访,3个月后均通过家庭访视进行观察,比较两组患儿出院后发生呼吸道感染和肠道感染的差异。结果观察组患儿在出院后3个月内呼吸道感染和肠道感染的发生率低于对照组,差异具有统计学意义(P0.05)。结论出院扁桃体炎患儿继续服用金双歧,可提高患儿机体免疫力,降低呼吸道和肠道感染的发生率;随访为观察患儿出院后健康状态,进行健康指导以及收集资料的重要手段。 相似文献
8.
This study, spread over a span of 2 years describes Candida infections in burn patients of an Indian hospital. A total of 220 burn patients were monitored and Candida could be isolated from 138 patients. A total of 228 different Candida species were obtained from various body locations of these patients. Species identification revealed that Candida albicans was the most predominant (45) followed by Candida tropicalis(33), Candida glabrata (13.5), C. parapsilosis (4), C. krusei (2.75) and C. kefyr (1.75). DNA fingerprinting of all C. albicans isolates was done by using CARE-2 probe. Fingerprinting analyses of all the C. albicans strains revealed that strains collected from different patients were different. It is noteworthy that patients with disseminated
candidiasis had a similar, but unique strain isolated from all body locations, suggesting a possibility that commensal isolates
might be turning pathogenic. Taken together, this is probably the first ever detailed survey of Candidainfections in burn patients in India and is expected to lead to better clinical management of this group of patients. 相似文献
9.
CNTF对烧伤大鼠血清引起大鼠海马神经元细胞毒性的影响 总被引:3,自引:0,他引:3
应用整体和离体神经元培养,观察CNTF对烧伤大鼠海马神经元及烧伤血清引起海马神经元损伤的影响,结果表明,大鼠烧伤后海马组织神经元数目减少,NO含量升高;烧伤大鼠血清可引起培养的海马神经元细胞存活率下降,培养液中NO含量升高;CNTF能降低烧伤大鼠海马组织中NO的含量,保护海马神经元,并能提高培养的海马神经元的存活率,减少培养液中NO含量,其作用呈剂量依赖性;CNTF对神经元存活率的影响与NO含量呈显著负相关,提示CNTF对烧伤大鼠血清引起的海马神经元损伤有保护作用,其作用机制可能是通过抑制NO的神经毒性。 相似文献
10.
Dae Won Kim Sung Ho Lee Min Jea Shin Kibom Kim Sae Kwang Ku Jong Kyu Youn Su Bin Cho Jung Hwan Park Chi Hern Lee Ora Son Eun Jeong Sohn Sung-Woo Cho Jong Hoon Park Hyun Ah Kim Kyu Hyung Han Jinseu Park Won Sik Eum Soo Young Choi 《BMB reports》2015,48(11):618-623
FK506 binding protein 12 (FK506BP) is a small peptide with a single FK506BP domain that is involved in suppression of immune response and reactive oxygen species. FK506BP has emerged as a potential drug target for several inflammatory diseases. Here, we examined the protective effects of directly applied cell permeable FK506BP (PEP-1-FK506BP) on corneal alkali burn injury (CAI). In the cornea, there was a significant decrease in the number of cells expressing pro-inflammation, apoptotic, and angiogenic factors such as TNF-α, COX-2, and VEGF. Both corneal opacity and corneal neovascularization (CNV) were significantly decreased in the PEP-1-FK506BP treated group. Our results showed that PEP-1-FK506BP can significantly inhibit alkali burn-induced corneal inflammation in rats, possibly by accelerating corneal wound healing and by reducing the production of angiogenic factors and inflammatory cytokines. These results suggest that PEP-1-FK506BP may be a potential therapeutic agent for CAI. [BMB Reports 2015; 48(11): 618-623] 相似文献