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991.
摘要 目的:探讨愈创紫草油改善头颈部恶性肿瘤放疗患者所致放射性皮肤黏膜损伤的临床疗效,以期为头颈部恶性肿瘤放疗患者所致放射性皮肤黏膜损伤提供新的治疗方法。方法:选取安徽中医药大学附属六安医院2021年3月-2023年3月头颈部恶性肿瘤放疗患者100例作为研究对象,随机数字表随机分为观察组和对照组,各50例。两组均采用适形调强放射治疗,对照组给予常规放疗皮肤管理与宣教,观察组在对照组基础上给予涂抹愈创紫草油治疗。比较两组皮肤黏膜损伤程度、临床疗效、放疗完成率、皮损愈合时间,放疗2、4、6周时数字评分法(NRS)评分、Karnofsky功能状态(KPS)评分、皮肤病生活质量量表(DLQI)评分;放疗前、放疗6周时炎性细胞因子[白介素-6(IL-6)、降钙素原(PCT)、超敏C反应蛋白(hs-CRP)]水平及皮肤不良反应。结果:观察组皮肤黏膜损伤程度分级低于对照组(P<0.05);观察组总有效率94.00%较对照组80.00%高(P<0.05);放疗4、6周时观察组NRS评分、DLQI评分低于对照组,KPS评分高于对照组(P<0.05);两组放疗完成率均为100%,观察组皮损愈合时间较对照组短(P<0.05);放疗6周时观察组血清IL-6、PCT、hs-CRP水平低于对照组(P<0.05);两组患者均未出现过敏所致皮疹、红肿、瘙痒等皮肤不良反应。结论:愈创紫草油可有效减轻头颈部恶性肿瘤放疗所致放射性皮肤黏膜损伤,降低血清炎性细胞因子水平,促进患者皮损愈合,提高生活质量,疗效显著,且安全性高。  相似文献   
992.
人体皮肤表面定居着多种微生物,这些微生物与皮肤健康密切相关。表皮葡萄球菌(Staphylococcusepidermidis)是正常人群皮肤表面微生物的主要成员之一,对维持皮肤的健康状态发挥着重要作用。在正常生理环境下,表皮葡萄球菌通过抗菌肽参与皮肤固有免疫,其细胞壁成分脂磷壁酸有助于适应性免疫系统的发育和启动,从而调节皮肤免疫过程。通过分泌鞘磷脂酶,表皮葡萄球菌可以对皮肤上的神经酰胺进行补充,同时可以增强角质形成细胞间的紧密连接,进而维护皮肤屏障稳态。表皮葡萄球菌可以和多种细菌进行交流,在皮肤抗菌防御中发挥着良性的作用,并且可以促进皮肤的再上皮化,加速伤口修复。本文归纳总结了表皮葡萄球菌在维持健康皮肤方面的最新研究结果及认识,有助于深入了解其作为潜在益生菌充分发挥对皮肤的有益影响,为皮肤病的治疗及化妆品的研发提供借鉴。  相似文献   
993.
Psychophysical measurements of itch and itchy skin (“alloknesis”—itch produced by innocuous mechanical stimulation) were obtained in human volunteers following intracutaneous or subcutaneous injections of histamine or papain into the volar forearm. Histamine and papain were given in doses of 0.1, 1, or 10 μg in 10 μl of saline. The effects of the depth of injection and of skin temperature on the latency, magnitude, and duration of itch were examined. Also, dose-response functions were obtained for the area of alloknesis produced by intracutaneous injections of histamine. Finally, the neural mechanisms underlying the spread of alloknesis were investigated via local anesthesia of the skin.

Intracutaneous and subcutaneous injections of histamine, but not papain, produced a sensation of itch without pain. The latency of itch was shorter after an intracutanous than after a subcutaneous injection of histamine. The mean latencies of itch produced by a 1-μg dose were 9.5 and 23.0 sec for intracutaneous and subcutaneous injections, respectively. No differences were observed in the magnitude or duration of itch. Similarly, the latency of itch was increased when the skin temperature at injection site was lowered to 15°C, whereas the magnitude and duration of itch were unaffected.

Intracutaneous and subcutaneous injections of histamine produced similar areas of alloknesis. However, the magnitude and duration of alloknesis were dependent on dose. The mean maximum areas of alloknesis produced by intracutaneous injections of 0.1, 1, and 10 μg of histamine were 28.3, 47.2, and 43.8 cm2, respectively. Alloknesis was present at 2 min after injection, increased to a maximum area without 10 min, and then gradually decreased during the next 25-40 min. Once developed, the area was typically abolished when the injection site was cooled to 1-4°C. Rewarming the injection site to 38°C returned the area to its original size. Also, when histamine was injected into a small area of skin anesthetized with Xylocaine, alloknesis failed to develop until the anesthetic wore off. In addition, when histamine was injected 5 mm distal to a thin mediolateral anesthetic barrier, alloknesis did not develop on the proximal side of the barrier.

These results demonstrate that histamine is effective in producing itch and alloknesis, and should be useful in correlative neurophysiological studies of the underlying mechanisms. It is suggested that both peripheral and central neural mechanisms are involved in the development of alloknesis.  相似文献   
994.
Equine sarcoid is a topically accessible model for the evaluation of anticancer peptides acting by physical membrane disruption avoiding the complexity of a systemic application. We aim at evaluating and improving natural peptides for host defence as lead structures, where we focus on the cationic and amphipathic peptide NK‐2. Cytotoxicity tests, fluorescence microscopy and a chip‐based biosensor, which enabled real‐time monitoring of cell metabolism, were applied. Cancer cell killing was dynamic with an initial phase of increased cellular respiration, followed by membrane destruction. NK‐2 was substantially improved and shortened. Novel peptides exhibited a fivefold improved activity against sarcoid cells, while haemolysis remained almost unaltered. Similar Zeta potential and similar amount of surface phosphatidylserine of sarcoid and normal skin cells are responsible for a lack of selectivity between these two cell types. Copyright © 2013 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   
995.
This work reviews results of in vivo dosimetry (IVD) for total skin electron beam (TSEB) therapy, focusing on new methods, data emerged within 2012. All quoted data are based on a careful review of the literature reporting IVD results for patients treated by means of TSEB therapy. Many of the reviewed papers refer mainly to now old studies and/or old guidelines and recommendations (by IAEA, AAPM and EORTC), because (due to intrinsic rareness of TSEB-treated pathologies) only a limited number of works and reports with a large set of numerical data and proper statistical analysis is up-to-day available in scientific literature. Nonetheless, a general summary of the results obtained by the now numerous IVD techniques available is reported; innovative devices and methods, together with areas of possible further and possibly multicenter investigations for TSEB therapies are highlighted.  相似文献   
996.
Confocal Raman microspectroscopy represents the advantage of giving structural and conformational information on samples without any destructive treatment. Recently, several studies were achieved to study the skin hydration, endogenous and exogenous molecules repartition in the skin using the confocal feature of this technique. Meanwhile, when working through a material boundary with a different refractive index, the main limitation remains the spatial precision, especially the distortion in the depth and the depth resolution. Recently, several authors described mathematical models to correct the depth and the resolution values. In this study, we combined theoretical approaches, proposed by different authors with experimental measurements to try to find out the most appropriate approach for correction. We then applied the corrections on in‐depth profiles tracking the penetration of Metronidazole, a drug produced by Galderma for rosacea treatment, through excised human skin. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
997.
Identification of genetic factors that modify complex traits is often complicated by gene-environment interactions that contribute to the observed phenotype. In model systems, the phenotypic outcomes quantified are typically traits that maximize observed variance, which in turn, should maximize the detection of quantitative trait loci (QTL) in subsequent mapping studies. However, when the observed trait is dependent on multiple interacting factors, it can complicate genetic analysis, reducing the likelihood that the modifying mutation will ultimately be found. Alternatively, by focusing on intermediate phenotypes of a larger condition, we can reduce a model’s complexity, which will, in turn, limit the number of QTL that contribute to variance. We used a novel method to follow angiogenesis in mice that reduces environmental variance by measuring endothelial cell growth from culture of isolated skin biopsies that varies depending on the genetic source of the tissue. This method, in combination with a backcross breeding strategy, is intended to reduce genetic complexity and limit the phenotypic effects to fewer modifier loci. We determined that our approach was an efficient means to generate recombinant progeny and used this cohort to map a novel s.c. angiogenesis QTL to proximal mouse chromosome (Chr.) 8 with suggestive QTL on Chr. 2 and 7. Global mRNA expression analysis of samples from parental reference strains revealed β-defensins as potential candidate genes for future study.  相似文献   
998.
Flower and fruit colors are important agronomic traits. To date, there is no forward genetic evidence that the glutathione S-transferase (GST) gene is responsible for the white flower color in peach (Prunus persica). In this study, genetic analysis indicated that the white-flower trait is monogenetic, is recessive to the non-white allele, and shows pleiotropic effects with non-white-flowered types. The genetic locus underpinning this trait was mapped onto chromosome 3 between 0.421951 and 3.227115 Mb by using bulked segregant analysis in conjunction with whole-genome sequencing, and was further mapped between 0 and 1.178149 Mb by using the backcross 1 (BC1) population. Finally, the locus was fine-mapped within 535.974- and 552.027-kb intervals by using 151 F2 individuals and 75 individuals from a BC1 self-pollinated (BC1S1) population, respectively. Pp3G013600, encoding a GST that is known to transport anthocyanin, was identified within the mapping interval. The analysis of genome sequence data showed Pp3G013600 in white flowers has a 2-bp insertion or a 5-bp deletion in the third exon. These variants likely render the GST non-functional because of early stop codons that reduce the protein length from 215 amino acids to 167 and 175 amino acids, respectively. Genetic markers based on these variants validated a complete correlation between the GST loss-of-function alleles and white flower in 128 peach accessions. This correlation was further confirmed by silencing of Pp3G013600 using virus-induced gene silencing technology, which reduced anthocyanin accumulation in peach fruit. The new knowledge from this study is useful for designing peach breeding programs to generate cultivars with white flower and fruit skin.  相似文献   
999.
1000.
There is increasing interest in developing abattoir-based measures to assist in determining the welfare status of pigs. The primary aim of this study was to determine the most appropriate place on the slaughter line to conduct assessments of welfare-related lesions, namely apparent aggression-related skin lesions (hereafter referred to as ‘skin lesions’), loin bruising and apparent tail biting damage. The study also lent itself to an assessment of the prevalence of these lesions, and the extent to which they were linked with production variables. Finishing pigs processed at two abattoirs on the Island of Ireland (n=1950 in abattoir A, and n=1939 in abattoir B) were used. Data were collected over 6 days in each abattoir in July 2014. Lesion scoring took place at two points on the slaughter line: (1) at exsanguination (slaughter stage 1 (SS1)), and (2) following scalding and dehairing of carcasses (slaughter stage 2 (SS2)). At both points, each carcass was assigned a skin and tail lesion score ranging from 0 (lesion absent) to 3 or 4 (severe lesions), respectively. Loin bruising was recorded as present or absent. Differences in the percentage of pigs with observable lesions of each type were compared between SS1 and SS2 using McNemar/McNemar-Bowker tests. The associations between each lesion type, and both cold carcass weight and condemnations, were examined at batch level using Pearson’s correlations. Batch was defined as the group of animals with a particular farm identification code on a given day. The overall percentage of pigs with a visible skin lesion (i.e. score>0) decreased between SS1 and SS2 (P<0.001). However, the percentage of pigs with a severe skin lesion increased numerically from SS1 to SS2. The percentage of pigs with a visible tail lesion and with loin bruising also increased between SS1 and SS2 (P<0.001). There was a positive correlation between the percentage of carcasses that were partially condemned, and the percentage of pigs with skin lesions, tail lesions and loin bruising (P<0.05). In addition, as the batch-level frequency of each lesion type increased, average cold carcass weight decreased (P<0.001). These findings suggest that severe skin lesions, tail lesions and loin bruising are more visible on pig carcasses after they have been scalded and dehaired, and that this is when abattoir-based lesion scoring should take place. The high prevalence of all three lesion types, and the links with economically important production parameters, suggests that more research into identifying key risk factors is warranted.  相似文献   
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