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11.
Pengfei Li Liming Ruan Ruofan Wang Tianqi Liu Gao Song Xiaofei Gao Guohua Jiang Xiaoyan Liu 《仿生工程学报(英文版)》2021,18(6):1378-1390
Nanofibers(NFs)have been widely used in tissue engineering such as wound healing.In this work,the antibacterial ZnO quantum dots(ZnO QDs)have been incorporated into the biocompatible poly(ε-caprolactone)/collagen(PCL/Col)fibrous scaffolds for wound healing.The as-fabricated PCL-Col/ZnO fibrous scaffolds exhibited good swelling,antibacterial activity,and biodegradation behaviors,which were beneficial for the applications as a wound dressing.Moreover,the PCL-Col/ZnO fibrous scaffolds showed excellent cytocompatibility for promoting cell proliferation.The resultant PCL-Col/ZnO fibrous scaffolds containing vascular endothelial growth factor(VEGF)also exhibited promoted wound-healing effect through promoting expression of transforming growth factor-β(TGF-β)and the vascular factor(CD31)in tissues in the early stages of wound healing.This new electrospun fibrous scaffolds with wound-healing promotion and antibacterial property should be convenient for treating wound healing. 相似文献
12.
Hong-Guang Zhang Bin Wang Yong Yang Xuan Liu Junjie Wang Ning Xin Shifeng Li Ying Miao Qiuyu Wu Tingting Guo Yukang Yuan Yibo Zuo Xiangjie Chen Tengfei Ren Chunsheng Dong Jun Wang Hang Ruan Miao Sun Xingshun Xu Hui Zheng 《Cell research》2022,32(10):897
Depression is a serious public-health issue. Recent reports have suggested higher susceptibility to viral infections in depressive patients. However, how depression affects antiviral innate immune signaling remains unknown. Here, we revealed a reduction in expression of Abelson helper integration site 1 (AHI1) in the peripheral blood mononuclear cells (PBMCs) and macrophages from the patients with major depressive disorder (MDD), which leads to attenuated antiviral immune response. We found that depression-related arginine vasopressin (AVP) induces reduction of AHI1 in macrophages. Further studies demonstrated that AHI1 is a critical stabilizer of basal type-I-interferon (IFN-I) signaling. Mechanistically, AHI1 recruits OTUD1 to deubiquitinate and stabilize Tyk2, while AHI1 reduction downregulates Tyk2 and IFN-I signaling activity in macrophages from both MDD patients and depression model mice. Interestingly, we identified a clinical analgesic meptazinol that effectively stimulates AHI1 expression, thus enhancing IFN-I antiviral defense in depression model mice. Our study promotes the understanding of the signaling mechanisms of depression-mediated antiviral immune dysfunction, and reveals meptazinol as an enhancer of antiviral innate immunity in depressive patients.Subject terms: Innate immunity, Ubiquitylation, Cell signalling 相似文献
13.
Zhenxiang He Chengjiang Ruan Pei Qin Denise M. Seliskar John L. Gallagher 《Ecological Engineering》2003,21(4-5):271-276
Kosteletzkya virginica (L.) Presl. is a perennial dicot halophytic species, that grows in brackish portions of coastal tidal marshes of the mid-Atlantic and southeastern United States. New saline mudflats have been increasing every year in Northern Jiangsu, China. In 1993, we introduced K. virginica (L.) into China from the Halophyte Biotechnology Center (University of Delaware, USA) as a potential species to improve the soil and develop ecologically sound saline agriculture. Our nearly 10 years of experimental research, both in a test garden and in the field, indicated that K. virginica adapts excellently to the heavy saline soils of Jiangsu Province, China. The average seed yield of K. virginica in 2001 at Yancheng was 638 kg/ha from 1-year old seedlings. There were significant variations among individuals from the unselected population of K. virginica on growth, quality, and seed yield traits. There is great potential to increase the seed yield if superior clones are selected. The seed yield of 35 selected individuals was six times greater than that of the average. Four growth traits of K. virginica were found to have a significant correlation with seed yield. However, there was no strong positive or negative correlation among seed quality traits. The mean seed weight and the germination ratio of the 35 selected individuals of K. virginica were 16.36±0.32 g and 76.11±1.82%, respectively. The percentage content of oil and crude protein in the seeds was 11.28±0.67 and 8.17±0.19%, respectively. The percentage of seed vigor of the selected individuals was 99%, as determined by soft X-ray radiography. 相似文献
14.
Rhizobitoxine is a phytotoxin synthesized by some strains of the legume symbiont genus Bradyrhizobium and the plant pathogen Pseudomonas andropogonis. We demonstrate here a new enzymatic assay which is 100-fold more sensitive than previous assays and can detect as little as 1.0 pmol of rhizobitoxine. The assay is based on the inhibition of Salmonella typhimurium beta-cystathionase by rhizobitoxine. Interestingly, beta-cystathionase from Bradyrhizobium japonicum is insensitive to rhizobitoxine at concentrations lower than 75 microM. 相似文献
15.
Xu Jiliang Zhang Xiaohui Zhang Zhengwang Zheng Guangmei Ruan Xiangfeng Zhang Keyin Xi Bo 《Frontiers of Biology in China》2006,1(2):174-181
Home range and habitat use of male Reeves’s pheasant (Syrmaticus reevesii) were studied during winter of 2001∼2002 and 2002∼2003 in the Dongzhai National Nature Reserve, Henan Province. Results from
five individuals of Reeves’s pheasant with over 30 relocations, indicated that the average size of home range was 10.03 ±
1.17 hm2 by Minimum Convex Polygon method, 8.60 ± 0.35 hm2 by 90% Harmonic Mean Transformation method, and 9.50 ± 1.90 hm2 by 95% Fixed Kernel method. It was observed that the winter range is smaller than that in the breeding season. The mean core
area of the home range was found to be 1.88 ± 0.37 hm2. Although the habitat composition of the core area varied greatly for individuals, a large part of the habitats used were
composed of confier and broadleaf mixed forests, masson pine forests, fir forests, and shrubs. Habitat use within the study
area was non-random, while habitats within home ranges were randomly used. Habitat use was dictated by tree diameter at breast
height, shrub height and coverage at 2.0 m. The proximity between forests and shrubs were also found to be important in providing
refuge for the birds during winter. Recommendations for conservation management include protecting the existing habitats in
Dongzhai National Nature Reserve, increasing suitable habitat for Reeves’s Pheasant through artificial plantations (e.g. firs),
and restoring some parts of the large shrub area into forests.
__________
Translated from Biodiversity Science, 2005, 13 (5) [译自: 生物多样性, 2005,13(5)] 相似文献
16.
In recent years, metabolism is talked highly important in cancer research, especially the lipid metabolism. Researchers believe that the de novo fatty acid synthesis plays an important role in tumor development, while many studies illustrated that Endocannabinoids have anti-tumorigenic actions, including anti-proliferation, apoptosis induction, and anti-metastatic effects, MAGL as an important decomposing enzyme of both lipid metabolism and endocannabinoids system, additionally as a part of a gene expression signature contributes to different aspects of tumourigenesis. 相似文献
17.
从酵母中提取谷胱甘肽的初步研究 总被引:28,自引:3,他引:28
考察了不同提取方法对从酵母中提取谷胱甘肽(GSH)的影响,热水抽提由于其提取收率高(90%),耗时短(10min)经济性强而明显优于其它提取方法,对732阳离子交换树脂纯化GSH进行了初步研究,主要研究了树脂颗粒大小对提纯GSH的影响,采用60~80目的树脂,GSH收率为57.6%,虽然比80目以上的树脂低10%但前者操作作所需时间只有后者的1/3。 相似文献
18.
Flavio I. Bachini Danilo Pereira Ruan Santos Matheus Hausen Glauber Pereira Camila Vieira Lee Taylor Marcelle Pegurier 《Biology of sport / Institute of Sport》2022,39(3):745
Capillary dried blood spot (DBS) samples facilitate field-based collection without venipuncture. This pilot study aims to evaluate the viability of creatine (Cr) and creatinine (Crt) quantification using fresh capillary serum (CrS/CrtS) and DBS samples (CrDBS/CrtDBS), using Flow Injection Analysis Mass Spectrometry (FIA – MS). Nine Olympic Athletes provided a capillary blood sample to assess CrS/CrtS and CrDBS/CrtDBS quantified by FIA – MS. No difference between CrtS (mean ± SD: 813.6 ± 102.4 μmol/L) and CrtDBS (812.4 ± 108.1 μmol/L) was observed with acceptable variance [SEM 88.7; CV 10.7%; ICC 0.57 (CI 95% 0.06 – 0.84)] and agreement [very strong (Spearman: r = 0.77; p < 0.01) or strong (Pearson: r = 0.56; p = 0.04); Bland Altman: lower (-193) and upper (+196) limits of agreement]. CrS (mean ± SD: 691.8 ± 165.2 μmol/L) was significantly different to CrDBS (2911 ± 571.4 μmol/L) with unacceptable variance [SEM 171.6; CV 27%; ICC 0.002 (CI 95% -0.02 – 0.07)] and ‘weak’ agreement [Spearman: r = 0.21, p = 0.47 and Pearson: r = 0.06, p = 0.84; Bland Altman lower (-3367) and upper (-1072) limits of agreement]. Crt quantification is viable using both CrtS and CrtDBS (but not for Cr and CrS/CrDBS), with the DBS tissue handling technique offering several methodological and practice facing advantages. Future work should expand upon the sample size, explore sport/discipline relevant analytes across a full competitive season, including key training, recovery and performance blocks of their periodized performance plan. 相似文献
19.
本文以离体培养的Raji细胞为材料,采用ELLMAN方法检测了不同剂量的He-Ne激光对Raji细胞膜表面SH含量的影响。发现0.5J/cm^2He-Ne激光能量可明显增加膜表面SH含量(P〈0.05)。大于或小于此剂量的He-Ne激光对膜表面SH含量的影响均不明显(P〉0.05)。提示0.5J/cm^2的激光能量对膜有刺激作用。 相似文献
20.
应用梯度离心和超速离心浓缩获得部分提纯的病毒制剂,产量约为7.45g/kg病叶提纯的病毒制剂的紫外吸收曲线呈典型的核蛋白吸收曲线,OD260/OD242和OD260/OD280的比值分别为1.24和1.38。病毒粒子呈线状,宽13—14nm,长度主要分布于250—300nm和550—700nm之间,1000nm以上的粒子也有检到。病毒外壳蛋白仅由一个分子量约为30Kd的亚基组成。在免疫电镜试验中、病毒粒子与日本WYMV抗血清发生强烈的血清学反应。新鲜病叶的超薄切片中可看到大量风轮体和膜状体。 相似文献