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141.
Fibroblasts from skin and skin lesions of patients with tuberous sclerosis (TS) and from skin of normal individuals were grown in culture. ELISA showed that the spent medium of those derived from TS skin lesions contained significantly more fibronectin (FN) than spent medium from the other cells. Amino acid compositional analysis of the FN from TS and normal sources revealed no substantial differences. However the FN of fibroblasts from TS-skin lesions was shown by HPAEC to contain a two- to three-fold increased content of carbohydrate. The changed monosaccharide composition was consistent with an increased content of N- and O-linked glycans and with the former containing polylactosamine chains. Fibroblasts from a normal individual were shown to proliferate more slowly and to produce larger cells when grown on FN from a TS skin lesion compared to growth on FN from normal skin. This revised version was published online in November 2006 with corrections to the Cover Date.  相似文献   
142.
143.
Wound healing is a complex and error-prone process. Wound healing in adults often leads to the formation of scars, a type of fibrotic tissue that lacks skin appendages. Hypertrophic scars and keloids can also form when the wound-healing process goes wrong. Leptin (Lep) and leptin receptors (LepRs) have recently been shown to affect multiple stages of wound healing. This effect, however, is paradoxical for scarless wound healing. On the one hand, Lep exerts pro-inflammatory and profibrotic effects; on the other hand, Lep can regulate hair follicle growth. This paper summarises the role of Lep and LepRs on cells in different stages of wound healing, briefly introduces the process of wound healing and Lep and LepRs, and examines the possibility of promoting scarless wound healing through spatiotemporal, systemic, and local regulation of Lep levels and the binding of Lep and LepRs.  相似文献   
144.
A previously undescribed skin abnormality, referred to as “linear skin markings” (LSM), has been identified in free-ranging common bottlenose dolphins (Tursiops truncatus) in the Indian River Lagoon, Florida (IRL). The lesions were identified during photo-identification surveys conducted from 2002 and 2015. LSM presented as distinct, parallel lines running dorso-ventrally on the torso and varied in length and width. The goals of this study were to determine (1) prevalence of the condition in IRL dolphins, (2) age and sex distribution of affected animals, (3) spatial and temporal distribution patterns, (4) duration of the condition, and (5) development of hypotheses regarding the etiology of the condition. Among 1,357 individual dolphins identified during the study period, 96 (7.0%) showed evidence of LSM. Nearly all (98.8%) cases with an established home range occurred in the northern and central regions of the IRL. The majority of cases of known sex were female (85%), of which 100% had given birth to one or more calves. The mean age of animals with LSM when first observed was 7.3 with a range of 1–20 years. The maximum observed duration of LSM was 15 years. Once observed, the condition persisted indefinitely. The etiology of LSM has not been established.  相似文献   
145.
应用皮肤益生素霜,对面部痤疮、化妆品过敏、黄褐斑共251例患者进行良好的调理。结果痤疮患者142例,治愈81例,有效45例,无效16例。化妆品过敏患者64例,治愈54例,有效9例,无效1例。黄褐斑患者43例,治愈11例,有效23例,无效9例。提示皮肤益生素霜能够起到良好的皮肤治疗和护理作用。  相似文献   
146.
The most commonly preserved soft tissues associated with ornithischian dinosaurs are skin remains. The apparent resistance of hadrosaur skin to decay, and its abundance in the fossil record relative to that of other tetrapods, has been attributed to factors such as thickness and composition. Here we report additional intrinsic factors within hadrosaur skin: 3D-preserved eumelanin-bearing bodies, dermal cells and blood vessel fragments in an organic matrix composed of protein fossilization products. The skin is much thinner than that of living mammals of similar size. It is likely that the preservation of hadrosaur skin is related to the arrangement of the layers composing it.  相似文献   
147.
游离股前外侧皮瓣Ⅰ期修复大面积深度眼镜蛇伤溃疡   总被引:1,自引:2,他引:1  
谭宇顺  李景新  张跃  余佩琦 《蛇志》2001,13(1):44-46
目的 探讨大面积深度眼镜蛇伤溃疡的修复方法。方法 对8例大面积深度眼镜蛇伤溃疡,采用游离股前外侧皮瓣,Ⅰ期修复创面。结果 8例皮瓣均全部成活,患肢外观及活动功能均满意。结论 游离股前外侧皮瓣是一种Ⅰ期修复大面积深度眼镜蛇伤溃疡的理想方法。  相似文献   
148.
Numerous reports have revealed an inverse association between consumption of some selective natural products and risk of developing cancer. In the present study the effect of 250 and 500 mg/kg body weight of Spirulina was examined on drug metabolising phase I and phase II enzymes, antioxidant enzymes, glutathione content, lactate dehydrogenase and lipid peroxidation in the liver of 7-week-old Swiss albino mice. The implications of these biochemical alterations have been further evaluated adopting the protocol of benzo(a)pyrene induced forestomach and 7,12 dimethylbenz(a)anthracene (DMBA) initiated and croton oil promoted skin papillomagenesis. Our primary findings reveal the Monofunctional nature of Spirulina as deduced from its potential to induce only the phase II enzyme activities associated mainly with carcinogen detoxification. The glutathione S-transferase and DT-diaphorase specific activities were induced in hepatic and all the extrahepatic organs examined (lung, kidney and forestomach) by Spirulina pretreatment (significance level being from p < 0.05 to p < 0.005) except for the low dose treatment in forestomach. With reference to antioxidant enzymes viz., superoxide dismutase, catalase, glutathione reductase, glutathione peroxidase and reduced glutathione were increased significantly by both the chosen doses of Spirulina from p < 0.01 to p < 0.005. Chemopreventive response was quantitated by the average number of papillomas per effective mouse (tumor burden) as well as percentage of tumor bearing animals. There was a significant inhibition of tumor burden as well as tumor incidence in both the tumor model systems studied. In the skin tumor studies tumor burden was reduced from 4.86 to 1.20 and 1.15 by the low and high dose treatment respectively. In stomach tumor studies tumor burden was 2.05 and 1.73 by the low and high doses of Spirulina treatment against 3.73 that of control.  相似文献   
149.
摘要 目的:探讨无创性皮肤屏障功能检测在朗格汉斯细胞组织细胞增生症(Langerhans cell histiocytosis,LCH)中的应用价值。方法:研究时间为2017年1月到2020年12月,选择在本院诊治的朗格汉斯细胞组织细胞增多症患者72例作为LCH组,同期选择健康体检者72例作为对照组。采用无创性皮肤屏障功能检测皮肤水分、经皮水分丢失(Transdermal water loss,TEWL)、油脂水平,同时检测所有入选者的免疫功能、皮肤菌群并进行相关性分析。结果:LCH组的皮肤水分低于对照组(P<0.05),TEWL、油脂水平高于对照组(P<0.05)。LCH组的乳酸杆菌(La)阳性率低于对照组(P<0.05),表皮葡萄球菌(Se)、痤疮丙酸杆菌(Pa)、金黄色葡萄球菌(Sa)阳性率高于对照组(P<0.05)。LCH组的CD163、ki-67表达阳性率分别为77.8 %、52.8 %,高于对照组的19.4 %和6.9 %(P<0.05)。在LCH组中,Pearson相关性分析显示皮肤水分与乳酸杆菌呈现正相关性(P<0.05),TEWL、油脂与表皮葡萄球菌、痤疮丙酸杆菌、金黄色葡萄球菌、CD163、ki-67呈现正相关性(P<0.05)。结论:无创性皮肤屏障功能检测在朗格汉斯细胞组织细胞增生症中的应用可反映患者的皮肤水分与油脂状况,也可间接反映患者的皮肤微生态与免疫功能状况。  相似文献   
150.
This study investigated the physiological function of suppressed melatonin through thermoregulation in a cold environment. Interactions between thermoregulation directly affected by exposure to a cold environment and indirectly affected by endogenous melatonin suppression by bright-light exposure were examined. Ten male subjects were exposed to two different illumination intensities (30 and 5000 lux) for 4.5?h, and two different ambient temperatures (15 and 27°C) for 2?h before sleep under dark and thermoneutral conditions. Salivary melatonin level was suppressed by bright light (p?<?0.001), although the ambient temperature condition had no significant effect on melatonin. During sleep, significant effects of pre-sleep exposure to a cold ambient temperature (p?<?0.001) and bright light (p?<?0.01) on rectal temperature (Tre) were observed. Pre-sleep, bright-light exposure led to an attenuated fall in Tre during sleep. Moreover, Tre dropped more precipitously after cold exposure than thermoneutral conditions (cold: ?0.54?±?0.07°C/h; thermoneutral: ?0.16?±?0.03°C/h; p?<?0.001). Pre-sleep, bright-light exposure delayed the nadir time of Tre under thermoneutral conditions (p?<?0.05), while cold exposure masked the circadian rhythm with a precipitous decrease in Tre. A significant correlation between the Tre nadir and melatonin level (r?=??0.774, p?<?0.05) indicated that inter-individual differences with higher melatonin levels lead to a reduction in Tre after cold exposure. These results suggest that suppressed endogenous melatonin inhibits the downregulation of the body temperature set-point during sleep. (Author correspondence: )  相似文献   
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