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11.
基于生物量、活性物质积累和抗氧化能力的当归高海拔种植区域选择 总被引:1,自引:0,他引:1
目的以根茎生物量、活性物质含量以及抗氧化能力为指标,选择适宜提高当归品质的高海拔种植区域。方法在严格控制种质、水分和土壤养分的条件下,以不同海拔(2 100、2 500和2 900 m)2年生当归根茎为材料,分别对干质量、活性物质含量以及抗氧化能力进行测定与分析。结果高海拔虽不能促进当归根茎生物量,却显著提高了活性物质的积累量和抗氧化能力;以单株积累量计算,2 900 m未抽薹当归根茎中阿魏酸、可溶性糖、酚和黄酮类含量分别为2 100 m植株的2.06、1.13、1.34和1.15倍;体外抗氧化能力也随海拔升高逐渐增加。综合分析表明,在2 100~2 900 m海拔内,未抽薹当归根茎中活性物质的总积累量(干质量和单株)均随海拔升高逐渐增加。结论提升当归种植海拔高度可显著提高根茎活性物质量;活性物质生物合成与积累受到低温和光照的综合调控。该研究结果将为提高当归产量和品质以及大面积种植栽培提供理论基础与依据。 相似文献
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The interaction between tissues and biomaterials (BM) has the purpose of improving and replacing anatomical parts of the human body, avoiding the occurrence of adverse reactions in the host organism. Unfortunately, the early failure of implants cannot be currently avoided, since neither a good mixture of mechanical and chemical characteristics of materials nor their biocompatibility has been yet achieved. Bioactive glasses are recognized to be a fine class of bioactive substances for good repair and replacement. BM interact with living bones through the formation of a hydroxyapatite surface layer that is analogous to bones. Bioglasses’ composition noticeably affects their biological properties, as does the synthesis method, with the best one being the versatile sol-gel technique, which includes the change of scheme from a ‘sol’ fluid into a ‘gel’. This process is widely used to prepare many materials for biomedical implants (e.g., hip and knee prostheses, heart valves, and ceramic, glassy and hybrid materials to serve as carriers for drug release). Nanoparticles prepared by the sol-gel method are interesting systems for biomedical implementations, and particularly useful for cancer therapy. This review provides many examples concerning the synthesis and characterization of the above-mentioned materials either taken from literature and from recently prepared zirconia/polyethylene glycol (PEG) hybrids, and the corresponding results are extensively discussed. 相似文献
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《Joint, bone, spine : revue du rhumatisme》2022,89(6):105407
ObjectiveTo investigate the potential role of US in the detection of ILD in a cohort of patients with RA.MethodsPatients with diagnosis of RA were consecutively enrolled. All patients underwent pulmonary examination, laboratory data, DLCO measure, chest HRCT and radiographs, and US examination. A healthy group was included as control group. US was performed according the 14-intercostal space scanning protocol using the following semiquantitative scale [0 = normal (≤ 5 B-lines); 1 = slight (≥ 6 and ≤ 15 B-lines); 2 = moderate, (≤ 16 and ≥ 30 B-lines); 3 = severe (≥ 30 B-lines)].ResultsA total of 74 RA patients and 74 healthy controls were included. Thirty of 74 patients (40.5%) showed US signs of ILD with respect to the healthy controls (3 subjects, 4.1%) (P < 0.001); whereas HRCT showed ILD in 27 (36.4%) of 74 patients. Among the 30 patients that showed US findings of ILD, 17 (56.6%) were asymptomatic from respiratory view-point. The sensitivity and specificity of US were 92% and 89% respectively. A positive correlation between US and HRCT findings were found (P < 0.001) whereas no correlation was found with chest radiographs and DLCO findings. Positive association between US findings and DAS28-ESR, anti-CCP and RF (P < 0.01 for each respectively) was found. Feasibility, represented by the mean time spent to perform the pulmonary US assessment was 7.8 minutes (± SD 1.2, range 6 to 10 minutes).ConclusionsOur results support the potential of US in detect accurately ILD in patients with RA and provide a rationale to consider it as a friendly screening tool to be implemented in early phases of the disease. 相似文献
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Chronic kidney disease (CKD) patients in dialysis (HD) are considered to be submitted to a continuous oxidative stress. This stress can cause damage on DNA and, consequently, contribute to the high levels of DNA damage observed in these patients. Due to the well-known role of polyphenols as antioxidant agents we proposed its use to reduce the levels of genotoxicity present in HD-CKD patients. The objective of this study was to evaluate the antigenotoxic effects of unfermented grape juice (UGJ) on HD-CKD patients. The levels of DNA damage were analyzed using different biomarkers, such as breaks and oxidized DNA bases by the comet assay, chromosome damage by the micronucleus test. In addition, TEAC (Trolox equivalent antioxidant capacity) was also evaluated. Thirty-nine patients were followed for six months, of whom 25 were supplemented by UGJ and 14 were not supplemented. The obtained results showed a significant decrease in the underlying levels of oxidative DNA damage, in the supplemented group. Regarding the clinical parameters, LDL and cholesterol, were significantly reduced in the patients studied after the supplementation period, although cholesterol was also decreased in the non-supplemented patients. In conclusion, in our studied group the supplementation with UGJ reduced the levels of oxidative DNA damage of HD-CKD patients. 相似文献
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Satoshi Ebata Ayumi Yoshizaki Takemichi Fukasawa Asako Yoshizaki-Ogawa Yoshihide Asano Kosuke Kashiwabara Koji Oba Shinichi Sato 《The Journal of dermatology》2022,49(1):179-183
The benefit of rituximab (RTX) for systemic sclerosis-associated interstitial lung disease (SSc-ILD) has been shown in previous clinical trials. However, predictors of RTX efficacy have not been clarified. We investigated whether B-cell responsiveness to RTX is related to therapeutic effect. Ten SSc-ILD patients treated with RTX in an independent clinical trial (Japan Registry of Clinical Trials, jRCTs031180373) were included in this analysis. Peripheral B-cell counts were examined retrospectively before RTX administration (baseline) and at 2, 4, 12, and 24 weeks after the first RTX administration, along with percent-predicted forced vital capacity (%FVC) before and 24 weeks after RTX treatment. Relative to baseline, the percentage of residual peripheral blood B cells at 2 weeks after RTX was negatively correlated with the %FVC improvement at the 24-week assessment (r = ?0.41, p = 0.04). In the subgroup with less than 5% B-cell persistence at week 2, %FVC at the 24-week assessment was significantly improved compared to baseline (p = 0.02). In another subgroup with more than 5% residual B cells, %FVC was not significantly different after 24 weeks compared to baseline (p = 0.41). In conclusion, the removal rate of B cells after 2 weeks of RTX treatment may be a useful surrogate marker of subsequent SSc-ILD improvement. 相似文献
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《Sleep medicine》2020
ObjectiveTo evaluate the presence of sleep disorders and its associations with exercise capacity and daily physical activity levels among children and adolescents with CF.MethodsChildren age 6–18 years with a diagnosis of CF were recruited. Information regarding sociodemographic profile, pulmonary function and nutritional status were collected. Sleep disorders (polysomnography), exercise capacity (modified shuttle test - MST) and daily physical activity levels (questionnaire and five days accelerometer use) were evaluated.ResultsThirty-one patients, median age of 9.6 years and forced expiratory volume in 1 s (FEV1) of 68.1 ± 24.4%, were included. Obstructive sleep apnea syndrome (OSAS) was present in 32.3% and nocturnal hypoxemia in 29%. The MST distance correlated with the mean peripheral oxyhemoglobin saturation (SpO2) during sleep (r = 0.40) and the percent of total sleep time with SpO2<90% (r = −0.49). The final MST SpO2 correlated with the occurrence of OSAS (r = −0.48) and mean nocturnal SpO2 (r = 0.45). Sedentary activities, as measured by accelerometry, correlated with sleep architecture, including the percent of stage II (r = 0.60) and rapid eye movement (REM) stage sleep (r = −0.37). Patients with OSAS and nocturnal hypoxemia presented lower values (p < 0.05) of distance and final SpO2 in the MST. Nocturnal hypoxemia was the main variable to influence exercise capacity (r2 = 0.521).ConclusionSleep disorders are distinctively related with exercise capacity and daily physical activity levels, as nocturnal hypoxemia is associated with exercise intolerance and sleep architecture disorders are associated with sedentary physical activity levels. 相似文献