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排序方式: 共有440条查询结果,搜索用时 15 毫秒
1.
Stefan Wolf Jeremy W. Deuel Maija Hollmn Gunther Felmerer Bong-Sung Kim Mauro Vasella Lisanne Grünherz Pietro Giovanoli Nicole Lindenblatt Epameinondas Gousopoulos 《International journal of molecular sciences》2021,22(7)
Lipedema is an adipose tissue disorder characterized by the disproportionate increase of subcutaneous fat tissue in the lower and/or upper extremities. The underlying pathomechanism remains unclear and no molecular biomarkers to distinguish the disease exist, leading to a large number of undiagnosed and misdiagnosed patients. To unravel the distinct molecular characteristic of lipedema we performed lipidomic analysis of the adipose tissue and serum of lipedema versus anatomically- and body mass index (BMI)-matched control patients. Both tissue groups showed no significant changes regarding lipid composition. As hyperplastic adipose tissue represents low-grade inflammation, the potential systemic effects on circulating cytokines were evaluated in lipedema and control patients using the Multiplex immunoassay system. Interestingly, increased systemic levels of interleukin 11 (p = 0.03), interleukin 28A (p = 0.04) and interleukin 29 (p = 0.04) were observed. As cytokines can influence metabolic activity, the metabolic phenotype of the stromal vascular fraction was examined, revealing significantly increased mitochondrial respiration in lipedema. In conclusion, despite sharing a comparable lipid profile with healthy adipose tissue, lipedema is characterized by a distinct systemic cytokine profile and metabolic activity of the stromal vascular fraction. 相似文献
2.
Yasin Cotur Michael Kasimatis Matti Kaisti Selin Olenik Charis Georgiou Firat Güder 《Advanced functional materials》2020,30(16)
A highly flexible, stretchable, and mechanically robust low‐cost soft composite consisting of silicone polymers and water (or hydrogels) is reported. When combined with conventional acoustic transducers, the materials reported enable high performance real‐time monitoring of heart and respiratory patterns over layers of clothing (or furry skin of animals) without the need for direct contact with the skin. The approach enables an entirely new method of fabrication that involves encapsulation of water and hydrogels with silicones and exploits the ability of sound waves to travel through the body. The system proposed outperforms commercial, metal‐based stethoscopes for the auscultation of the heart when worn over clothing and is less susceptible to motion artefacts. The system both with human and furry animal subjects (i.e., dogs), primarily focusing on monitoring the heart, is tested; however, initial results on monitoring breathing are also presented. This work is especially important because it is the first demonstration of a stretchable sensor that is suitable for use with furry animals and does not require shaving of the animal for data acquisition. 相似文献
3.
Jhon Larry Moreno Thierry Tran Borja Cantero-Tubilla Karina López-López Luis Augusto Becerra Lopez Lavalle Dominique Dufour 《International Journal of Food Science & Technology》2021,56(3):1171-1183
The physicochemical and physiological attributes of three contrasting commercial varieties of Musaceae, Dominico Harton (plantain), Guineo (cooking banana) and Gros Michel (dessert banana), were evaluated and statistically analysed during post-harvest ripening. Quality attributes differed markedly among varieties, both in fresh fruits and during ripening. Variety (V) had a significant effect (P < 0.001) on all attributes except total soluble solids (TSS), carotenes and total chlorophyll. Storage time (ST) had a significant effect on all attributes except colour parameter b* and total carotenes. Starch levels decreased significantly (P < 0.001) during ripening, with nearly complete hydrolysis in Gros Michel, followed by Guineo and Dominico Harton. Discriminant analysis showed that central diameter, TSS of the pulp, colour parameter a* and total starch had the highest weight in the differentiation among varieties. These results point out which parameters may help improve current methods for monitoring ripening of bananas, in particular the commercially important varieties in this study. 相似文献
4.
5.
本文研究了不同贮藏温度(0℃、5℃、10℃、15℃、20℃、25℃、30℃)对草莓呼吸强度、感官评价、失重率、硬度、相对电导率、糖酸比、维生素C和色差的影响。研究表明:贮藏温度越高,草莓呼吸越旺盛,货架寿命越短,草莓30℃条件下的呼吸强度是0℃条件下的13.97倍;草莓在0℃、5℃、10℃、15℃、20℃、25℃、30℃条件下贮藏的商品寿命分别为9 d、7 d、6 d、5 d、3d、2 d、8 h。随着贮藏温度的升高,草莓的失重率、相对电导率和呼吸强度迅速升高,而草莓的感官评价、硬度、糖酸比、维生素C含量、L*、hue值逐渐降低;贮藏在0℃的草莓品质保持最好,贮藏9 d后的感官评价、失重率、硬度、相对电导率、糖酸比、Vc含量、L*和hue值分别为5.4、3.18%、11.13 N、39.05%、12.48、22.01 mg/100 g、37.84、32.81。 相似文献
6.
本文通过实验分别测量人体吸气和呼气的速度、温度、相对湿度、氧气浓度、二氧化碳浓度,得到人体呼吸的基本性能参数。结合中国人员体型特征数据分析了不同年龄对耗氧量、二氧化碳释放量和新陈代谢的影响、不同运动状态对耗氧量、新陈代谢率和呼吸商的影响,数据结果与ASHRAE手册中的推荐值对比。实验结果表明,随着年龄的增长,人体的耗氧量、人体新陈代谢量和二氧化碳释放量呈现出了下降的趋势,人在轻度劳动时,人的耗氧量、呼吸商与手册中的推荐值是一致的,但是人体能量代谢率却比手册中的大10%左右.中等劳动和重劳动时人体耗氧量和新陈代谢率符合ASHRAE中的推荐范围,但是取值却偏向较大值。这为新风量和气流组织的优化设计提供了科学的理论依据。 相似文献
7.
Formation of Uniform Water Microdroplets on Wrinkled Graphene for Ultrafast Humidity Sensing 下载免费PDF全文
Zhen Zhen Zechen Li Xuanliang Zhao Yujia Zhong Li Zhang Qiao Chen Tingting Yang Hongwei Zhu 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(15)
Portable humidity sensors with ultrafast responses fabricated in wearable devices have promising application prospects in disease diagnostics, health status monitoring, and personal healthcare data collecting. However, prolonged exposures to high‐humidity environments usually cause device degradation or failure due to excessive water adsorbed on the sensor surface. In the present work, a graphene film based humidity sensor with a hydrophobic surface and uniformly distributed ring‐like wrinkles is designed and fabricated that exhibits excellent performance in breath sensing. The wrinkled morphology of the graphene sensor is able to effectively prevent the aggregation of water microdroplets and thus maximize the evaporation rate. The as‐fabricated sensor responds to and recovers from humidity in 12.5 ms, the fastest response of humidity sensors reported so far, yet in a very stable manner. The sensor is fabricated into a mask and successfully applied to monitoring sudden changes in respiratory rate and depth, such as breathing disorder or arrest, as well as subtle changes in humidity level caused by talking, cough and skin evaporation. The sensor can potentially enable long‐term daily monitoring of breath and skin evaporation with its ultrafast response and high sensitivity, as well as excellent stability in high‐humidity environments. 相似文献
8.
A novel wearable sensor system was developed for monitoring respiration and pulse using polyvinylidene fluoride (PVDF) piezoelectric films as sensor materials. Due to the different signal intensity between respiration and pulse, a “double-sided arch” structure and a “thin-shell” structure were designed and fabricated as substrates for the respiratory sensor and pulse sensor, respectively. These sensors installed on belts can be easily tied on the chest, abdomen, or wrist for comfortable fit. In order to obtain clear respiratory and pulse signals from the sensor patch, some high-quality signal processing modules were designed. The digital signals were transmitted to a computer via Bluetooth and displayed by LabVIEW software. The fundamental principle and functional verification of the developed sensor system were described in this study. By comparing the sensor signals from the proposed structure with those of flat structure, it can be concluded that the proposed sensor is more sensitive and stable than its flat counterpart. In addition, the whole sensor system has the features of ease of use and comfortable to wear. All these make the proposed sensor system a promising sensing device for respiration and pulse real time monitoring. 相似文献
9.
Anolda Četkauskaitė Aurelijus Zimkus Jezi Borovik 《The International journal of environmental studies》2013,70(3):259-260
Pesticide toxicity databases usually include data on pure chemicals (active ingredients). Technical pesticides formulations, however, are mixtures with adjuvants as applied to fields/crops. Two formulations of the same pesticide can differ in their environmental fate and their toxicity. This work presents the evaluation of the toxicity of the dinitroaniline herbicide, pendimethalin by simultaneous analysis of its respiration rate and generation of a membrane potential (Δ Ψ) in rat liver mitochondria. Chromatography grade pendimethalin (8.2·10?5 ‐ 5.47·10?4 M or 23 – 154 ppm) caused lower enhancement of the mitochondrial respiration and decrease of the Δ Ψ than technical grade pendimethalin (Stomp), i.e. the mixture of pure ingredient and adjuvant(s). These effects are comparable to those of 2,4‐dinitrophenol. Pure and technical grade pendimethalin acts as an uncoupler of oxidative phosphorylation in mitochondria (enhances respiration and diminishes Δ Ψ). These data conflict with the statement, presented in the US EPA manual Recognition and Management of Pesticides Poisonings, that pendimethalin does not act as an uncoupler of oxidative phosphorylation. 相似文献
10.