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101.
植物多酚类成分提取分离研究进展   总被引:4,自引:1,他引:4  
陈亮  李医明  陈凯先  贾琦 《中草药》2013,44(11):1501-1507
植物多酚是一种广泛存在于植物体内的多元酚类次生代谢产物,随着多酚类成分在抗氧化、抗菌、抗病毒、抗微生物、调血脂和血糖等多方面活性的发现和阐明,植物多酚成为当前研究的热点之一.多酚类成分由于其结构上的复杂性和不稳定性,目前在提取分离上还存在一定的困难.对中药中多酚类成分的提取分离方法进行总结,旨在为下一步分离纯化多酚类成分提供比较系统的信息依据.  相似文献   
102.
目的:研究水翁花黄酮类化合物2’,4’-二羟基-6’-甲氧基-3’,5’-二甲基查耳酮(DMC)体外诱导人肝癌细胞SMMC-7721凋亡作用及其分子机制。方法:采用改进的Sellins-Cohen方法检测不同浓度的DMC对SMMC-7721细胞DNA片段化的影响。用PCR-ELISA法测定肿瘤细胞的端粒酶活性,用半定量RT-PCR法测定c-myc和人端粒酶逆转录酶(hTERT)的mRNA表达量,Western blot法检测c-myc及hTERT蛋白的表达。结果:DMC作用于人肝癌SMMC-7721细胞后,引起SMMC-7721细胞DNA片段化率增大,片段化率效果有明显的浓度依赖性。与对照组相比,20μmol·L-1DMC处理48 h后,肝癌细胞的端粒酶活性下降了(66.2±2.1)%。c-myc和hTERT的mRNA表达水平分别下降了(67.3±2.1)%,(64.4±2.3)%,c-myc和hTERT的蛋白表达水平分别下降了(69.6±1.9)%,(71.3±2.4)%。结论:DMC能诱导SMMC-7721细胞凋亡,其凋亡机制可能与c-myc基因和hTERT的mRNA以及蛋白的表达降低有关。  相似文献   
103.
衰老是人体生命周期中按照一定的规律发生在整体、器官、组织、细胞的形态和功能的演变,表现为一系列随增龄而显现的全身性、渐进性、衰退性的变化或紊乱。衰老包括生理和心理两方面的衰老。体质是对人体生理功能和心理状态等方面特质的高度概括,适用于人体的整个生命阶段,中老年时期是人体衰老加速的时期,其衰老的进程及表现特征受体质的影响。平和体质延缓衰老,偏颇体质加速衰老,并且不同偏颇体质的衰老表现也存在差异。本研究对体质与衰老的相关性进行了理论分析;探讨了9种体质类型对衰老速度和表现特征的影响及预测作用。  相似文献   
104.
目的 观察普济宣肺消毒饮对急性支气管炎化痰作用.方法 用随机、对照、前瞻性研究方法,将87例急性支气管炎(表寒里热证)患者随机分为治疗组44例和对照组43例,治疗组服用普济宣肺消毒饮,对照组用急支糖浆治疗,观察对咯痰的影响,疗程为7d.结果 治疗组对咯痰、发热、头痛、恶风等症状有明显治疗作用,治疗后咯痰疗效和评分低于对照组,化痰疗效优于对照组(P<0.05).结论 普济宣肺消毒饮有一定的化痰作用.  相似文献   
105.
Background: Malnutrition is associated with poor outcomes after stroke. However, the association between malnutrition and post-stroke depression (PSD) remains unelucidated. We aimed to explore the association between geriatric nutritional risk index (GNRI) and depression after ischemic stroke. Methods: In total, 344 patients with ischemic stroke were included in this analysis. The GNRI was calculated from serum albumin level, weight, and height at admission. Malnutrition was defined using the GNRI cutoff points. A lower GNRI score indicates an elevated nutritional risk. The outcome was depression, measured 14 days after ischemic stroke. Logistic regression models were used to estimate the association between the GNRI and risk of PSD. Results: A total of 22.9% developed PSD 14 days after stroke. The mean GNRI was 99.3 ± 6.0, and 53.8% of the patients had malnutrition. After adjusting for covariates, baseline malnutrition was not associated with risk of PSD (OR, 0.670; 95%CI, 0.370–1.213; p = 0.186). The restricted cubic splines revealed a U-shaped association between the GNRI and PSD. Compared to moderate GNRI, higher GNRI (OR, 2.368; 95%CI, 0.983–5.701; p = 0.085) or lower GNRI (OR, 2.226; 95%CI, 0.890–5.563; p = 0.087) did not significantly increase the risk of PSD. Conclusion: A low GNRI was not associated with an increased risk of depression after ischemic stroke.  相似文献   
106.
To investigate the dynamic compressive properties of concrete after high temperature and rapid cooling, an experimental study was carried out by considering five temperatures and four strain rates. The coupling effect of high temperature and strain rate on concrete damage morphology and mechanical parameters was comparatively analyzed. The main conclusions are as follows: the compressive damage morphology of concrete is affected by strain rate development trends of significant variability under different temperature conditions. As the strain rate increases, the compressive stress and elastic modulus of concrete are gradually increased. As the temperature increases, the increase in compressive stress is gradually reduced by the strain rate. For the temperatures of 20 °C and 800 °C, the increase in compressive stress by the strain rate is 38.69% and 7.78%, respectively. Meanwhile, SEM and CT scanning technology were applied to examine the mechanism of the effect of high temperature and strain rate on the mechanical properties of concrete from the microscopic perspective, and the corresponding constitutive model was proposed.  相似文献   
107.
IntroductionThe aim of this research was to assess the association between inflammation and oral health and diabetes, as well as the mediating role of oral hygiene practice in this association.MethodsData were from the 2009–2010 National Health and Nutrition Examination Survey. The analytical sample consisted of 2,191 respondents aged 50 and older. Poor oral health was clinically defined by significant tooth loss (STL) and periodontal disease (PD). Diabetes mellitus (DM) was determined by glycemic levels. The outcome variable was serum C-reactive protein (CRP) level, dichotomised as ≥1 mg/dL (elevated CRP) vs <1 mg/dL (not elevated CRP). Two path models, one using STL and DM as the independent variable, the other using PD and DM as the independent variable, were estimated to assess the direct effects of having poor oral health and DM on elevated CRP and the mediating effects of dental flossing.ResultsIn path model 1, individuals having both STL and DM (adjusted odds ratio [AOR], 1.92; 95% confidence interval [CI], 1.30–2.82) or having STL alone (AOR, 2.30; 95% CI, 1.68–3.15) were more likely to have elevated CRP than those with neither STL nor DM; dental flossing (AOR, 0.92, 95% CI, 0.88–0.96) was associated with lower risk of elevated CRP. In path model 2, no significant association was found between having both PD and DM and elevated CRP; dental flossing (AOR, 0.91; 95% CI:, 0.86–0.94) was associated with lower risk of elevated CRP.ConclusionsFindings from this study highlight the importance of improving oral health and oral hygiene practice to mitigate inflammation. Further research is needed to assess the longer-term effects of reducing inflammation.Key words: Tooth loss, Periodontal disease, Diabetes, Inflammation  相似文献   
108.
糖尿病神经病变是糖尿病最常见和最复杂的并发症之一,可累及全身神经系统的任何部分,大约发生在近50%的糖尿病患者中.通常在1型糖尿病患者中,它出现较晚,而在2型糖尿病的早期就能发现.  相似文献   
109.
Background:For the rectal cancer <5 cm from anal margin, extralevator abdominoperineal resection (eAPR) has been accepted widely by surgeons. However, the rate of perineal infection following up eAPR is approximately 70%. We did the study with the aim of evaluating the effect and safety of transperineal pelvic drainage combined with lateral position (TPDLP) on perineal wound in patients undergoing eAPR.Methods:Patients were randomly assigned to N-TPDLP group (standard arm) or TPDLP group (intervention arm). In the standard arm, surgery was completed after abdominal drainage tube was placed in pelvic. Comparatively, an additional transperineal wound drainage tube was applied in the experimental arm. Postoperatively, patients of both 2 groups were informed not to sit to reduce perineal compression until the perineal wound healed. But lateral position was demanded in the intervention arm. The primary endpoint was the rate of uncomplicated perineal wound healing defined as a Southampton wound score of <2 at 30 days postoperatively. Patients were followed for 6 months.Results:In total, 60 patients were randomly assigned to standard arm (n = 31) and intervention arm (n = 29). The mean perineal wound healing time was 34.2 (standard deviation [SD] 10.9) days in TPDLP arm, which significantly differ from 56.4 (SD 34.1) in N-TPDLP arm (P = .001). At 30 days postoperatively, 3 (10%) of 29 patients undergoing TPDLP were classified into grade 4 according to Southampton wound score, however, 16 (52%) of 31 patients were classified into grade 4 in control arm, and significantly difference was observed between randomization groups (P = .001). What''s more, perineal wound pain was assessed at 30 days postoperatively, and it is discovered that the pain degree of patients in control arm was significantly more severe than the interventive arm (P = .015).Conclusion:In the present study, we found that TPDLP generated a favorable prognosis for perineal wounds with acceptable side-effects.  相似文献   
110.
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