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BACKGROUND/PURPOSE: Tattoos have become increasingly popular followed by a growing demand for tattoo removal, and yet there is little knowledge and monitoring of tattoo pigment deposition in skin layers. The purpose of this pilot study is to describe optical coherence tomography image characteristics of intradermal tattoos. METHODS: We included five black tattoos in 3 female volunteers, 39, 35 and 30 years old. In vivo imaging of tattoo pigments in the skin is possible with optical coherence tomography (OCT), a novel non-invasive, in vivo optical imaging technology with a resolution and a penetration in skin high enough for visualization of tattoo pigment in the dermis. RESULTS: In optical coherence tomography images tattoo pigments clusters appear as dark, homogenous vertical columns and structures in the papillary dermis. OCT-scanned normal skin (without tattoos) appeared to be free of this dark structure. CONCLUSION: We have demonstrated that OCT can be used to visualize clusters of light absorbing pigments in a predictable manner.  相似文献   
3.
目的:探讨宫颈癌的临床、病理特点、诊治方法及预后因素。方法:收集1996年1月至2001年1月226例宫颈癌患者进行回顾性分析。结果:平均患病年龄为48.18岁。130例患者为阴道流血,70例为阴道流液,25例下腹疼痛,l例精神减退、贫血、浮肿。病理分期:Ⅰ期病例数为169例(75%);Ⅱ期病例数为3l例(13.72%);Ⅲ期病例数为23例(10.18%);Ⅳ期病例数为3例(1.1%)。比较2l例宫颈鳞癌与宫颈腺癌的转移,显示后者的腹主动脉旁淋巴结转移、肾上腺转移、子宫转移、胸水形成明显高于前者。结论:重视宫颈癌发病相关因素及临床症状,争取早期诊断,严格手术病理分期,选择适当治疗方案。  相似文献   
4.
A fibrinolytic enzyme obtained from B. subtilis was purified, using DEAE-cellulose column chromatography, and gel filtration on Sephadex G-100. The preparation was homogeneous as tested by gel filtration on Sephadex G-200, and disc electrophoresis. The molecular weight of this enzyme was 29.400 estimated by gel filtration on Sephadex G-100. The optimum pH for enzyme activity was 7.2. Copper ions significantly increased enzyme activity, while Zn++ and Mn++ caused marked inhibition.  相似文献   
5.
This study examined the effect of prolonged submaximal exercise followed by a self-paced maximal performance test on cholesterol (T-Chol), triglycerides (TG), and high-density lipoprotein cholesterol (HDLC). Nine trained male athletes cycled at 70% of maximal oxygen consumption for 60 min, followed by a selfpaced maximal ride for 10 min. Venous blood samples were obtained at rest, at 30 and 60 min during submaximal exercise, and immediately after the performance test. Lactic acid, haematocrit (Hct), haemoglobin (Hb), T-Chol and TG were measured in the blood, while plasma was assayed for HDL-C. Plasma volume changes in response to exercise were calculated from Hct and Hb values and all lipid measurements were corrected accordingly. In order to ascertain the repeatability of lipid responses to exercise, all subjects were re-tested under identical testing conditions and experimental protocols. When data obtained during the two exercise trials were analysed by two-way ANOVA no significant differences (P > 0.05) between tests were observed. Consequently the data obtained during the two testing trials were pooled and analysed by one-way ANOVA. Blood lactic acid increased non-significantly (P > 0.05) during the prolonged submaximal test, but rose markedly (P < 0.05) following the performance ride. Lipid variables ascertained at rest were within the normal range for healthy subjects. ANOVA showed that blood T-Chol and TG were unchanged (P > 0.05), whereas HDL-C rose significantly (P < 0.05) in response to exercise. Post hoc analyses indicated that the latter change was due to a significant rise in HDL-C after the performance ride. It is concluded that apparent favourable changes in lipid profile variables occur in response to prolonged submaximal exercise followed by maximal effort, and these changes showed a good level of agreement over the two testing occasions.  相似文献   
6.
In a comparison of causal attributions following success and failure in hypothetical social, athletic, and academic situations, high self-esteem grade school children were more likely than low self-esteem children to attribute their success to ability and their failure to either lack of effort or bad luck. Low self-esteem children, on the other hand, attributed their success more often than high self-esteem children to good luck (and in social situations to effort and task ease as well) and their failure to lack of ability. Whereas prior studies that focused only on the internal-external dimension found that low and high self-esteem children differed in their attributional style to success but not to failure, the present study found that when distinctions between behavioral and characterological attributions (stability and globality dimensions) were included, the two groups differed significantly in response to both success and failure. Although perhaps not generalizable beyond the present attribution measure, the most pronounced attribution differences between low and high self-esteem children were observed in the social domain, the least in the academic domain, with athletics falling in between. Finally, it was found that sex and age (within the limited fourth- to sixth-grade range examined in the present study) did not alter the overriding difference in attributional style between low and high self-esteem children.This study is based on a doctoral dissertation submitted by the first author under the supervision of the last author in partial fulfillment of the requirements for the Ph.D. degree at the University of Vermont.  相似文献   
7.
The removal of metal cations inhibits the deprotonation process of the protonated Schiff base during the photocycle of bacteriorhodopsin. To understand the nature of the involvement of these cations, a spectroscopic and kinetic study was carried out on bacteriorhodopsin samples in which the native Ca2+ and Mg2+ were replaced by Eu3+, a luminescent cation. The decay of Eu3+ emission in bacteriorhodopsin can be fitted to a minimum of three decay components, which are assigned to Eu3+ emission from three different sites. This is supported by the response of the decay components to the presence of 2H2O and to the changes in the Eu3+/bR molar ratio. The number of water molecules coordinated to Eu3+ in each site is determined from the change in its emission lifetime when 2H2O replaces H2O. Most of the emission originates from two “wet” sites of low crystal-field symmetry—e.g., surface sites. Protonated Schiff base deprotonation has no discernable effect on the emission decay of protein-bound Eu3+, suggesting an indirect involvement of metal cations in the deprotonation process. Adding Eu3+ to deionized bacteriorhodopsin increases the emission intensity of each Eu3+ site linearly, but the extent of the deprotonation (and color) changes sigmoidally. This suggests that if only the emitting Eu3+ ions cause the deprotonation and bacteriorhodopsin color change, ions in more than one site must be involved—e.g., by inducing protein conformation changes. The latter could allow deprotonation by the interaction between the protonated Schiff base and a positive field of cations either on the surface or within the protein.  相似文献   
8.

Health agencies call for the immediate mobilization of existing interventions in response to numerous child and family mental health concerns that have arisen as result of the COVID-19 pandemic. Answering this call, this pilot study describes the rapid, full-scale change from a primarily clinic-based Parent–Child Interaction Therapy (PCIT) model to a virtual service model (i.e., I-PCIT) in an academic and community-based program in Miami, Florida. First, we describe the virtual service training model our program developed and its implementation with 17 therapists (MAge?=?32.35, 88.2% female, 47.1% Hispanic) to enable our clinic to shift from providing virtual services to a small portion of the families served (29.1%) to all of the families served. Second, we examine the effect of I-PCIT on child and caregiver outcomes during the 2-month stay-at-home period between March 16, 2020, and May 16, 2020, in 86 families (MChildAge?=?4.75, 71% Hispanic). Due to the rapid nature of the current study, all active participants were transferred to virtual services, and therefore there was no comparison or control group, and outcomes represent the most recently available scores and not treatment completion. Results reveal that I-PCIT reduced child externalizing and internalizing problems and caregiver stress, and increased parenting skills and child compliance with medium to large effects even in the midst of the COVID-19 pandemic. Finally, the study examined components of our virtual service training model associated with the greatest improvements in child and caregiver outcomes. Preliminary findings revealed that locally and collaboratively developed strategies (e.g., online communities of practice, training videos and guides) had the strongest association with child and caregiver outcomes. Implications for virtual service delivery, implementation, and practice in the midst of the COVID-19 pandemic are discussed.

  相似文献   
9.
IntroductionThe human immunodeficiency virus 1 (HIV‐1) pandemic is characterized by numerous distinct sub‐epidemics (clusters) that continually fuel local transmission. The aims of this study were to identify active growing clusters, to understand which factors most influence the transmission dynamics, how these vary between different subtypes and how this information might contribute to effective public health responses.MethodsWe used HIV‐1 genomic sequence data linked to demographic factors that accounted for approximately 70% of all new HIV‐1 notifications in New South Wales (NSW). We assessed differences in transmission cluster dynamics between subtype B and circulating recombinant form 01_AE (CRF01_AE). Separate phylogenetic trees were estimated using 2919 subtype B and 473 CRF01_AE sequences sampled between 2004 and 2018 in combination with global sequence data and NSW‐specific clades were classified as clusters, pairs or singletons. Significant differences in demographics between subtypes were assessed with Chi‐Square statistics.ResultsWe identified 104 subtype B and 11 CRF01_AE growing clusters containing a maximum of 29 and 11 sequences for subtype B and CRF01_AE respectively. We observed a > 2‐fold increase in the number of NSW‐specific CRF01_AE clades over time. Subtype B clusters were associated with individuals reporting men who have sex with men (MSM) as their transmission risk factor, being born in Australia, and being diagnosed during the early stage of infection (p < 0.01). CRF01_AE infections clusters were associated with infections among individuals diagnosed during the early stage of infection (p < 0.05) and CRF01_AE singletons were more likely to be from infections among individuals reporting heterosexual transmission (p < 0.05). We found six subtype B clusters with an above‐average growth rate (>1.5 sequences / 6‐months) and which consisted of a majority of infections among MSM. We also found four active growing CRF01_AE clusters containing only infections among MSM. Finally, we found 47 subtype B and seven CRF01_AE clusters that contained a large gap in time (>1 year) between infections and may be indicative of intermediate transmissions via undiagnosed individuals.ConclusionsThe large number of active and growing clusters among MSM are the driving force of the ongoing epidemic in NSW for subtype B and CRF01_AE.  相似文献   
10.
Background: The treatment of Pseudomonas keratitis has many limitations, and further investigation to identify more effective approaches is required. We therefore studied the possible contribution of the debridement effect of 193-nm excimer laser on Pseudomonas keratitis in rabbit eyes. Methods: Pseudomonas keratitis was induced in 30 rabbit eyes by inflicting controlled central corneal scratches and applying a drop of Pseudomonas aeruginosa suspension. After 24 h, one cornea of each animal was photo-ablated (excimer laser: fluency 90 mJ/cm2, 10 Hz, 213 pulses), yielding 50 m of tissue ablation, while the follow cornea served as control. Five groups of six animals each were formed and received: a subconjunctival injection of gentamicin 20, mg (group 1), topical 14 mg/ml gentamicin hourly (group 2) or every 2.5 h (group 3), or NaCl 0.9% hourly (group 4) for 8 h. In group 5, animals were sacrificed without additional treatment. After 9 h corneas were excised, homogenized, serially diluted, and plated on agar blood plates. The numbers of colony-forming units (CFU) per cornea were statistically evaluated (Mann-Whitney test). Results: In control eyes, a greater decrease of CFU was observed in group 2 than in group 3 (P = 0.03). In laser-ablated eyes, there was no difference in CFU between groups 2 and 3. Comparison of the excimer-treated and control eyes revealed a greater number of bacteria (CFU) in controls only in group 3 (P=0.02). Conclusion: Our study suggests that controlled debridement of cornea with excimer laser may improve the effect of topical antibiotics.Presented at ECORA First Annual Meeting, 5 October 1993, Bonn, Germany  相似文献   
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