54 research outputs found
沙格列汀治疗2型糖尿病病人致心衰风险的荟萃分析
目的:系统评价2型糖尿病病人用沙格列汀治疗与心衰风险的相关性。方法:检索中文科技期刊全文数据库(维普)、万方数据-数字化期刊群、中国期刊全文数据库(中国知网)、PubMed和Cochrane library建库至2017年12月的相关文献。按Cochrane系统评价法筛选沙格列汀致心衰的所有随机、对照临床试验(RCT),将纳入的文献进行数据提取和质量评价后,应用RevMan 5.3软件进行meta分析。结果:共纳入11篇文献,meta分析结果显示:沙格列汀致心衰的风险高于对照组,差异有统计学意义[RR=1.20,95%CI(1.02,1.42),P=0.03]。进一步研究发现,5mg/d沙格列汀单药或联合治疗致心衰的风险高于对照组,差异有统计学意义[RR=1.24,95%CI(1.05,1.46),P=0.01];2.5、10mg/d沙格列汀无论单药或联合治疗致心衰的风险与对照组比较均无显著性差异[2.5mg/d沙格列汀RR=0.69,95%CI(0.31,1.55),P=0.37;10mg/d沙格列汀RR=0.18,95%CI(0.02,1.67),P=0.13]。结论:使用5mg/d沙格列汀治疗可增加心衰风险,而其他剂量的沙格列汀均未发现增加心衰的风险。沙格列汀治疗2型糖尿病的远期安全性需进行更多大样本、高质量、长期随访的RCT加以验证
Action of DcR3 recombinant protein of myocardial tissue in diabetic rats
目的:研究诱骗受体3(dCr3)在正常大鼠、糖尿病(dM)大鼠心肌组织的表达,dCr3重组蛋白对心肌组织凋亡相关分子表达以及心肌细胞凋亡的影响,探讨dCr3对dM大鼠心肌细胞凋亡的作用。方法:一次性腹腔注射链脲佐菌素建立大鼠dM模型,尾静脉注射不同剂量的dCr3重组蛋白[1.2 Mg/(鼠·d)、0.8 Mg/(鼠·d)、0.4 Mg/(鼠·d)]40 d。rTPCr检测心肌组织dCr3 MrnA、fAS MrnA、fASl MrnA的表达。WESTEr blOT分析凋亡相关蛋白bCl-2、CASPASE-8的表达。双抗夹心ElISA检测血液中Il-1β、Tnf-α及lfn-γ水平的变化,HE染色观察心肌细胞凋亡的百分率。结果:dCr3治疗组大鼠与dM组比较心肌组织dCr3 MrnA高表达,fAS MrnA、fASl MrnA表达下调。CASPASE-8蛋白水平下调,bCl-2蛋白水平上调,以中剂量组的作用最明显。各dCr3治疗组血清Il-1β、Tnf-α和Ifn-γ水平均有不同程度的降低(P<0.05,P<0.01)。心肌细胞凋亡的百分率下降(P<0.05)。结论:dCr3重组蛋白有抑制dM大鼠心肌细胞凋亡的作用,其机制与竞争fAS,阻断fASl诱导细胞凋亡,心肌细胞表达dCr3,凋亡相关因子CASPASE-8下调、bCl-2上调及细胞因子水平的降低有关。Objective:To study the expression of DcR3 of myocardial tissue in diabetic mouse and normal rats and the impact of DcR3 recombinant protein to the expression of related molecules and myocardial cell apoptosis to discuss the action of DcR3 to myocardial cell apoptosis in Diabetic rats.Methods: Intraperitoneally injected streptozotocin one time to establish the model of Diabetic rats.Injected different doses of DcR3 recombinant protein to tail vein[1.2 mg /( rat·d),0.8 mg /( rat·d),0.4 mg /( rat·d)]40 d.The expression of DcR3 mRNA,Fas mRNA and Fas L mRNA of myocardial tissue was detected with RT-PCR;the expression of apoptosis related molecules Bcl-2 and Caspase-8 was analyzed with Western blot;the IL-1β,TNF-α and LFN-γ of the blood was detected with double antibody sandwich ELISA;the percentage of myocardial cell apoptosis was observed with HE dyeing.Results: To compare the DcR3 treatment group with diabetic group,the expression DcR3 of myocardial tissue was high,the expression of Fas mRNA and Fas L mRNA was descended.The Caspase-8 protein was ascended and the Bcl-2 protein was descended.The middle dose group was the most obvious.the IL-1β,TNF-α and IFN-γ in the blood was descended differently in each DcR3 treatment group( P < 0.05,P < 0.01).The percentage of myocardial cell apoptosis was declined( P < 0.05).Conclusion: DcR3 recombinant protein have the action of inhibiting the rats' myocardial cell apoptosis,the mechanism is related to competing with Fas,blocking-up Fas L of inducing apoptosis,expressing DcR3 of myocardial cell,the descending of apoptosis related factors Caspase-8,the ascending of Bcl-2 and the reduction of cytokine levels
生物法制备纳米银溶胶的稳定性
利用生物还原法制备纳米银溶胶,借助于UV-Vis表征技术对其热稳定性和化学稳定性进行考察。结果表明:生物法制备的纳米银溶胶在100℃下加热6h,UV-Vis谱图未发生明显变化;H+和具有高价阳离子的电解质对其稳定性的影响明显;OH-对银溶胶的稳定性影响相对较弱。生物法制备的纳米银溶胶在热稳定性、化学稳定性方面均略优于柠檬酸三钠法制得的银溶胶
Study on the risk factors for intrauterine infection of hepatitis B virus among pregnant women
目的探讨厦门市孕妇乙型肝炎病毒(hepatitis B virus,HBV)感染情况和HBV宫内感染的影响因素。方法在1; 064名孕妇第一次到医院建立孕产妇保健卡时进行问卷调查并检测其血清乙肝标志物,根据检测结果选择外周血乙型肝炎表面抗原(hepatitis B; surface antigen,HBsAg)阳性的产妇179例随访至其分娩,并采集其分娩时的脐血和胎盘组织。对脐血进行HBsAg和HBV; DNA的检测,对胎盘组织进行HBsAg的检测。采用chi~2检验和非条件Logistic回归分析相关因素与HBV宫内感染的关系。结果被调查的1; 064名孕妇中,HBsAg阳性的孕妇共179名,感染率为16.8%。对179名HBsAg阳性的孕妇的脐血进行检测发现,发生HBV宫内感染的孕妇共; 34名,感染率为19.0%。孕妇HBV宫内感染的危险因素为胎盘HBsAg阳性、孕妇血清乙型肝炎E抗原(hepatitis B e; antigen,HBeAg)阳性、孕前超重,OR分别为5.123(95% CI:1.422 ~ 18.413)、4.619(95%; CI:1.225 ~ 17.534)、 3.343(95% CI:1.233 ~; 9.092)。结论对于HBsAg和HBeAg双阳性的超重/肥胖孕妇,其新生儿可能发生HBV宫内感染,应加强自身防护措施,合理规避HBV宫内感染风; 险。Objective To investigate the prevalence of hepatitis B virus (HBV); infection in pregnant women and the risk factors for Intrauterine; infection of HBV among pregnant women in Xiamen. Methods Total 1 064; pregnant women were included in this study. A questionnaire was; performed to collect the general information of the subjects and HBV; infection status was tested on the first day when they came to the; hospital. Then HBsAg positive pregnant women were selected and followed; until delivery. We collected their cord blood and placenta tissue when; they delivery. HBsAg and HBV DNA in cord blood and HBsAg in placental; tissue were detected. Chi-square test and the non-conditional Logistic; regression analysis were conducted to investigate the correlation; between HBV intrauterine infection and risk factors. Results 179 out of; the 1 064 pregnant women were HBsAg positive. The infection rate was; 16.8%. 34 out of 179 HBsAg positive pregnant women were found; intrauterine transmission with a rate of 19.0%. The risk factors for the; occurrence of HBV intrauterine transmission were placenta HBsAg positive; (OR = 5.123, 95% CI:1.422-18.413),mothers with hepatitis B e; antigen(HBeAg) positive (OR = 4.619, 95% CI:1.225-17.534) and; overweight(OR = 3.343, 95% CI:1.233-9.092), respectively. Conclusions; Placenta HBsAg positive,mothers with HBeAg positive and overweight are; independent risk factors for the occurrence of HBV intrauterine; transmission.国家自然科学基金; 厦门市科技计划项
Survey and Evaluation of Heavy Metals, Nitrate and Nitrite Contamination in Vegetables in Xiamen's Market
为了解厦门市蔬菜中有害重金属、硝酸盐和亚硝酸盐的污染情况,于2004年8月至2005年12月从厦门市各超市、农贸市场、蔬菜批发市场和蔬菜产地上采集46个品种532份蔬菜样品,用国标法(GB/T5009.11-17-1996、GB/T5009.33-2003)分别分析蔬菜中的重金属、硝酸盐和亚硝酸盐的含量。结果表明,检测样品中Pb、Cd、As、Hg、硝酸盐和亚硝酸盐的平均值分别为0.0099、0.083、0.056、0.003、1090.3、0.59mg/kg;根据国家标准1-2,仅部分品种如菠菜、甘蓝、花菜、萝卜的铅超标,有潜在污染风险;大部分蔬菜中砷、汞、镉三种重金属的含量都较低,潜在的污染风险不大。硝酸盐污染程度严重的占36.5%;中、重度污染的占20.2%;轻度的占43.3%,硝酸盐含量依次为嫩茎叶菜类>根茎类>花菜类>瓜菜类>鲜豆菜>茄果类>水生蔬菜类,各样品间含量差别较大;而蔬菜中亚硝酸盐含量相对较低。The contents of heavy metal (Pd, Cd, As, Hg), nitrate and nitrite in vegetables from the markets and plant fields were investigated in Xiamen. The vegetable samples supplied seasonally were collected during August 2004 and December 2005. 532 samples in 46 groups of vegetables were analyzed according to GB/T5009.11-17-1996 and GB/T 5009.33-2003 to evaluate the status of the contamination. The results showed that the average contents are 0.0099, 0.083, 0.056, 0.003, 1090.3, 0.59 mg/kg for Pb, Cd, As, Hg, NO3-, NO2-, respectively. According to national standards[1-2], the samples of standard exceeding lead contents were found only in some limited vegetables. The potential trend of lead pollution was little. The contents of arsenic, mercury and cadmium in the most samples were very low, the pollution hazards of these three heavy metals were not serious. The prevalence of severe nitrate contamination was 36.5% in samples analyzed, the prevalence of heavy and medium nitrate contamination was 20.2%, the prevalence of mild contamination was 43.3%. The content of nitrate in vegetables was ranked in the following descent order, tender stem and leaf vegetables>root and stem vegetables>inflorescent vegetables>melon vegetables>beans>eggplant and fruit vegetables>water plant vegetables. However the contents in diferent species differed greatly. The nitrite in vegetables was comparably low
贵金属纳米颗粒及其催化剂的生物还原制备技术
利用自行筛选的具有强还原能力的菌株制备得到银纳米颗粒,所得颗粒的粒径基本在10 nm以下,主要集中在2~8nm。将生物还原过程进一步引入催化剂制备过程,得到负载型银催化剂和负载型钯催化剂,并将催化剂分别应用于1,2-丙二醇空气氧化合成丙酮醛、CO氧化生产CO2以及蒽醌加氢反应中
Pd-AgNbO_3光催化剂的合成及其光催化活性研究
采用浸渍法制备Pd-AgNbO3光催化剂,并运用XRD、XPS、SEM-EDS和DRS等方法对光催化剂进行表征与分析。以亚甲基蓝染料(MB)为降解污染物,考察Pd掺杂对AgNbO3光催化活性的影响。结果表明,Pd引入后AgNbO3的晶型结构及表面性质并未发生变化。DRS分析表明,Pd掺杂后光催化材料在可见光区的吸光度明显提高。光催化降解实验表明,当Pd的掺杂量为0.8%(质量分数,下同),热处理温度为400℃,煅烧时间为3h时,光催化降解活性最高,MB降解率为92.2%。Pd-AgNbO3光催化降解MB符合一级反应动力学特性
铯添加对VO_x/SBA-15催化剂丙烷氧化脱氢性能影响
我们考察了碱金属铯的添加对具有单一活性中心(分立的VO4四面体)的VOx/SBA-15催化剂上丙烷氧化脱氢反应性能的影响,发现铯的加入可以显著改善丙烯的选择性.在相同的丙烷转化率时,丙烯选择性提高了约10%.对催化剂的X射线衍射,拉曼光谱,程序升温还原,吡啶吸附IR光谱和程序升温脱附表征结果表明,少量碱金属的加入,并未改变活性中心的结构及其可还原性能,但明显降低了催化剂表面酸量,尤其是B酸量,从而有利于产物丙烯的脱附,抑制了深度氧化产物COx的产生,提高了丙烯的选择性
焙烧气氛对Ru/Al_2O_3催化剂上甲烷部分氧化制合成气反应性能的影响
采用气相色谱、质谱和原位时间分辨红外光谱等技术对空气和Ar气氛中焙烧的Ru/Al2O3催化剂样品上甲烷部分氧化(POM)制合成气反应进行了跟踪,并采用化学吸附、X射线衍射、拉曼光谱和H2-程序升温还原等技术对催化剂进行了表征.结果表明,在Ru/Al2O3-Air上POM反应出现振荡现象,而在Ru/Al2O3-Ar上则可较平稳地进行.经600°C还原后,Ru/Al2O3-Air上Ru的分散度仅为1%,而Ru/Al2O3-Ar上接近9%.这是导致两种样品上POM反应性能差异的主要因素.新鲜催化剂上存在两类Ru物种,分别是与载体相互作用较弱、较易还原的RuO2物种以及与载体相互作用较强、较难还原的Ru-O-Al物种.前者在POM反应过程中被还原为金属Ru0,后者则可随温度的升降发生周期性的还原和氧化,进而改变催化剂对CH4燃烧、重整或部分氧化等反应的相对活性,导致Ru/Al2O3-Air上POM反应尾气中各组分的浓度随时间而发生振荡
1978~2008年中国湿地类型变化
分别基于美国陆地卫星(Landsat MSS/TM/ETM+)和中巴资源卫星(CBERS-02B)影像数据,以人工目视解译为主,完成了中国1978~2008年4期(基准年分别为1978,1990,2000和2008年)湿地遥感制图,并进行了大量的室内外验证.在此基础上,对我国湿地现状及近30年来湿地变化进行了初步分析,得到以下主要结论:(ⅰ)截止2008年,中国湿地面积约为324097km2,其中以内陆沼泽(35%)和湖泊湿地(26%)为主.(ⅱ)1978~2008年,中国湿地面积减少了约33%,而人工湿地增加了约122%.过去30年里湿地减少的速度大幅降低,由最初5523km2/a(1978~1990年)降为831km2/a(2000~2008年).(ⅲ)减少的自然湿地(包括滨海湿地和内陆湿地),其类型变化由湿地向非湿地转化的比例逐渐降低.初期(1978~1990年)几乎全部(98%)转换为非湿地;在1990~2000年间减少的自然湿地约有86%转化为非湿地,而在2000~2008年,这一比例下降为77%.(ⅳ)气候变化和农业活动是中国湿地变化的主要驱动因素,湿地变化在中国分为三大不同特征区域,即西部三省/自治区(西藏、新疆和青海)、北部两省/自治区(黑龙江和内蒙古)和其他省市区.其中西部区域尤其是青藏高原,湿地变化的驱动因子以气候增温为主;新疆湿地由于气候增温和农业活动共同作用造成变化不大.北部省/自治区的湿地变化则主要由农业活动引起;而其他省市区的湿地变化几乎完全受控于人类的农业经济活动
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