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61.
桑黄总三萜的提取及其体外抗脑胶质瘤U251活性 总被引:1,自引:2,他引:1
目的:优化药用真菌桑黄总三萜的超声提取工艺并测定其对脑胶质瘤U251生长的抑制作用.方法:采用正交设计试验对超声辅助提取过程中影响桑黄总三萜得率的乙醇体积分数、超声时间、超声温度和料液比等因素进行优化;采用MTT比色法测定桑黄总三萜对U251细胞株增殖的抑制率,应用倒置相差显微镜观察桑黄总三萜对肿瘤细胞形态结构的影响.结果:超声辅助提取桑黄总三萜的最佳工艺条件为70%乙醇,超声提取20 min,温度60℃,料液比1∶25.在此条件下,桑黄总三萜提取率可达9.40 mg·g-1.桑黄总三萜对脑胶质瘤U251细胞株有抑制增殖作用,且表现出浓度依赖关系,倒置相差显微镜下可见部分细胞形成凋亡小体.结论:采用超声辅助提取桑黄总三萜时间短、得率高,是一种高效、快捷的方法,桑黄总三萜可抑制脑胶质瘤U251细胞株的增殖,诱导肿瘤细胞凋亡. 相似文献
62.
McGarvey BD Attygalle AB Starratt AN Xiang B Schroeder FC Brandle JE Meinwald J 《Journal of natural products》2003,66(10):1395-1398
Six new labdane-type, non-glycosidic diterpenes, sterebins I-N (1-6), were isolated from the leaves of Stevia rebaudiana. Their structures, analogous to those of the previously described sterebins A-H, were elucidated on the basis of spectroscopic and chemical studies. 相似文献
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64.
为探讨糖尿病周围神经病变中医辨证和针灸治疗的临床思路,概括病机特点,总结治疗规律,对近10年的52篇针灸临床文献资料进行了整理、分析,根据中医针灸理论,结合笔者的临床体会进行了论述.认为本病以气阴两虚为本,血瘀脉络为标;常多脏受累同病,但重在肝、肾、脾、胃.治疗原则当标本兼顾,以通为要,从整体入手,调理脏腑.组方配穴常用四肢穴配合脏腑俞募穴,远近结合,佐以随证配穴.针灸疗法应早期介入,多法合用,疗效确切. 相似文献
65.
人内质网分子伴侣BiP的克隆、表达及其在RA患者血清抗体检测中的作用 总被引:1,自引:0,他引:1
以类风湿关节炎(rheumatoid arthritis,RA)患者滑膜组织文库cDNA为模板,用PCR方法扩增得到1965 bp人内质网分子伴侣BiP的全长cDNA,将其克隆入OmicsLinkTM表达载体pReceiver-B01a,构建重组表达质粒pReceiver-B01a-BiP。重组表达质粒导入大肠杆菌BL-21(DE3)菌株中诱导表达目的蛋白,表达产物以Ni+-NTA agarose层析柱纯化。SDS-PAGE和免疫印迹法(Western blot)分析发现,表达产物以可溶性蛋白和包涵体形式共同存在,表达量约占菌体蛋白总量的20%~30%。相对分子质量约为80000,纯度达到电泳级。经免疫印迹法鉴定,获得的BiP重组蛋白可以与RA患者血清反应,检测的抗BiP抗体在RA患者血清中的阳性率为75.4%(49/65),明显高于系统性红斑狼疮(systemic lupus erythe-matosus,SLE)患者14.6%(7/48)、原发性干燥综合征(primary Sj gren’s syndrome,pSS)患者7.3%(4/55)及正常人0%(0/71)(P<0.01)。表明,经原核表达获得的BiP全长蛋白,RA患者血清抗体可以很好结合,有望应用于临床血清学诊断。 相似文献
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67.
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
68.
This work was mainly focused on the processing-parameter-related microstructure and properties of ultrafine WC-10Co-0.4VC-0.5Cr3C2 cemented carbide. The samples were prepared via a spark plasma sintering (SPS) technique using nano WC and Co powders and the corresponding inhibitor VC and Cr3C2 powders. The influence of the processing process on the microstructure and mechanical properties of ultrafine-grained cemented carbide was investigated under different ball-milling times and sintering temperatures. The results showed that the grain size of WC decreased with increasing ball-milling time and decreasing sintering temperature and that the specific gravity of ε-Co increased with increasing ball-milling time. The hardness of cemented carbide increased with increasing ball-milling time and decreased with increasing sintering temperature due to the corresponding variation in grain size and the relative density of samples. The transverse fracture strength (TRS) was mainly affected by ball-milling time. The increase in ball-milling time led to decreased TRS values, mainly ascribed to the formation of WC particle agglomeration and the decreased WC-Co eutectic temperature. In addition, temperature changes were found to have little effect on TRS. The samples sintered at 1250 °C with a ball-milling time of 60 h had comprehensive mechanical properties. Their average grain size, relative density, hardness, and TRS were 355.5 nm, 95.79%, 2035.5 kg/mm2, and 2155.99 MPa, respectively. 相似文献
69.
Huabin Luo Bei Wu Angela R. Kamer Samrachana Adhikari Frank Sloan Brenda L. Plassman Chenxin Tan Xiang Qi Mark D. Schwartz 《International dental journal》2022,72(4):484
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
70.
骨整合义耳修复创伤性全耳廓缺损 总被引:2,自引:0,他引:2
目的探讨骨整合义耳修复创伤性全耳廓缺损的可行性和临床效果。方法回顾性分析19例创伤性全耳廓缺损采用骨整合义耳修复患者。其中先天性小耳畸形全耳再造失败者12例,硫酸烧伤1例,高温铝水烫伤1例,车祸所致4例,刀砍伤1例。所有病例得到随诊,时间3~5年。结果所有患者均1次治愈,有一个形态逼真、色泽自然的外观,用骨整合方法固位的义耳配戴稳定,对日常生活无影响。结论骨整合义耳修复方法简便、创伤小、治疗周期短,无并发症,效果满意。对全耳再造失败者是一有效的治疗补救,对耳廓连同周围组织大面积缺损后瘢痕愈合者是可优先选择的方法。 相似文献