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51.
氯化镧对内毒素诱导巨噬细胞肿瘤坏死因子表达的影响 总被引:1,自引:1,他引:1
目的 探讨稀土化合物氯化镧对内毒素效应的影响。 方法 分离培养小鼠腹腔巨噬细胞 (M) ,用内毒素 (lipopolysaccharide ,LPS)对其进行诱导实验。采用ELISA法及SYBRGreen荧光定量RT PCR方法 ,观察氯化镧对LPS诱导的小鼠M肿瘤坏死因子α(TNFα)分泌及TNFαmRNA表达的影响。BALB/C小鼠随机分为 2组 ,分别给予致死量LPS及经氯化镧处理的LPS ,观察 7d内小鼠死亡率。 结果 经氯化镧处理的LPS诱导的小鼠 ,MTNFα分泌量及TNFαmRNA表达水平均明显低于LPS组 (P <0 .0 1)。经氯化镧处理的致死量LPS攻击小鼠 ,其死亡率明显低于LPS对照组。 结论 氯化镧具有降低内毒素毒性、抑制LPS诱导小鼠MTNFα分泌及TNFαmRNA表达的作用 相似文献
52.
目的对内膜修整后所取得的内膜组织按妊娠结果的不同分组进行分子水平的分析和检测,寻找合适的内膜发育分子标志物,早期预测辅助生殖技术(ART)患者的妊娠结果。方法随机选择10例接受增殖期子宫内膜修整术患者,其B超及组织学检查结果表明内膜处于相同发育阶段,按妊娠结果分为妊娠组与未妊娠组,抽提每例的子宫内膜组织总RNA,4例妊娠患者和3例未妊娠患者的内膜组织RNA符合芯片检测要求,使用Affymetrix U133 plus 2.0基因芯片进行表达谱分析。结果妊娠组与未妊娠组子宫内膜组织具有218个差异表达基因(≥2倍),其中177个基因在未妊娠组高表达,41个基因在妊娠组高表达。差异基因主要涉及代谢、细胞通讯和胞内过程调控等生物学过程,参与离子结合、信号传导和物质转运等重要功能。结论妊娠组与未妊娠组的增殖期子宫内膜细胞表达在转录组水平上差异明显,某些重要差异表达基因(LAMA4i、ntegrinα6和MMP1)有可能成为便利的早期预测ART患者妊娠结果的分子标志物。 相似文献
53.
目的 寻找与尿道下裂发病密切相关的基因,探讨尿道下裂形成机制.方法 ①实验组为12例尿道下裂患儿,年龄6~12个月,平均8个月.尿道下裂中度5例,重度7例.组织标本取自尿道成形手术时切取的尿道板组织.②对照组为6例年龄匹配的男性患儿,留取包皮环切时的正常表皮组织.用Tri-Reagent分别提取总RNA,与含22 000个人类基因的寡核苷酸基因芯片杂交、洗脱、染色、扫描,基因强度变化行方差分析(ANOVA,P<0.01)和Tukey分析,基因表达强度变化>2倍作为有意义的基因,比较尿道下裂和正常组织之间基因表达差异.从上调表达的基因中选择雌激素敏感基因行RT-PCR,标本除上述患儿RNA外,再增加年龄配对的3例中度、1例重度尿道下裂和2例年龄配对的RNA作为对照,即对照、中度和重度尿道下裂患者RNA标本各8例,验证芯片结果.结果 尿道下裂组织与正常组织之间存在明显的基因表达差异,共筛选出表达强度变化>2倍的基因94个,其中中度尿道下裂与正常比较,47个基因上调表达(P<0.01);重度尿道下裂与正常比较,68个基因上调表达(P<0.001);重度与中度比较,17个基因上调表达(P>0.05).上调表达的基因中发现了4个雌激素敏感基因CYR61、结缔组织生长因子、ATF3和GADD45β,基因芯片和RT-PCR均证实其在尿道下裂组织中的表达明显高于正常对照.结论 异常表达的基因与尿道下裂的发生有关,尿道下裂组织中雌激素敏感基因上调表达参与了尿道下裂的发病机制. 相似文献
54.
Dr. Arni Raghavendrarao Raghuram M.Ch. Subbiah Kumar MD Kathamuthu Balamurugan DA Arulmurugan DA Ramiah Krishnan M.Ch. Perichiappan Sivakami BS Eluvathingal Varghese John M.Ch. 《Indian Journal of Thoracic and Cardiovascular Surgery》2006,22(3):178-181
Background Beating heart surgery has now become the commonest technique of doing Coronary Artery Bypass Graft Surgery (CABG) in our country.
It is being used even in such high risk situations like diffuse coronary disease and Critical Left Main stem Stenosis (LMCS)
with good results. The aim of this study is to retrospectively review our results in Off-Pump Coronary Artery Bypass Surgery
(OPCAB) in patients with critical left main stem stenosis.
Methods This study is a retrospective analysis of the data of patients who underwent primary coronary artery bypass surgery. During
the period from April 2003 to September 2005 a total of 64 patients underwent OPCAB procedure for critical LMCS. During the
same period 10 patients underwent CABG on Cardio Pulmonary Bypass (CPB). The age range was 36–77yrs. The sex distribution
was M: F 53∶10. Ten patients were done as emergency. 2 of them were on Intra Aortic Balloon Pump (IABP) support preoperatively.
10 patients were high risk with a Euro score of ≥5.
Results Left Internal Mammary Artery (LIMA) was used in 78% of cases. Average grafts per patient was 2.96. The median ventilation
time was 5.91 hrs. New IABP insertion in postoperative period was required in 1 patient. One patient was reexplored for bleeding.
There was one perioperative myocardial infarction. 57% of patients did not need any blood transfusion. There was no conversion
to CPB. There was no operative mortality. Inotropes were used in ten cases.
Conclusions OPCAB is a safe method of revascularization in patients with critical LMCS. Preoperative IABP is useful in patients with cardiogenic
shock. However, there is a place for CPB in patients needing additional procedures like Mitral Valve repair (MV repair) or
Dor's procedure or when the vessels are very diffusely diseased. Those patients who are unstable despite IABP support may
be managed by Beating heart On Pump (BHOP) technique. 相似文献
55.
56.
目的:探讨不同呼吸机湿化管道系统在老年机械通气患者中的应用效果。方法:选取老年机械通气患者140例,随机分为3组,其中A组(n=43)使用MR410型湿化管道系统,B组(n=47)使用MR730型湿化管道系统,C组(n=50)采用MR 850型一次性双加热式、自动加水加湿湿化管道系统。观察3组湿化效果、并发症发生情况、通气时间及管道护理情况。结果:C组湿化效果适中比例最高,其次为B组,A组最低,3组间差异有统计学意义(P<0.01)。C组无导管痰痂和气道痉挛的发生,A组发生率最高,3组间差异有统计学意义(P<0.01)。C组通气时间、管道总更换次数、呼吸机管道护理时数均低于A、B组,差异有统计学意义(P<0.01)。结论:使用MR850型一次性双加热式、自动加水加湿湿化管道系统湿化效果最好,能降低并发症发生率,缩短通气时间和护理工作量。 相似文献
57.
58.
Jacques DA Ndawinz Xavier Anglaret Eric Delaporte Sinata Koulla-Shiro Delphine Gabillard Albert Minga Dominique Costagliola Virginie Supervie 《Bulletin of the World Health Organization》2015,93(8):521-528
Objective
To propose two new indicators for monitoring access to antiretroviral treatment (ART) for human immunodeficiency virus (HIV); (i) the time from HIV seroconversion to ART initiation, and (ii) the time from ART eligibility to initiation, referred to as delay in ART initiation. To estimate values of these indicators in Cameroon.Methods
We used linear regression to model the natural decline in CD4+ T-lymphocyte (CD4+ cell) numbers in HIV-infected individuals over time. The model was fitted using data from a cohort of 351 people in Côte d’Ivoire. We used the model to estimate the time from seroconversion to ART initiation and the delay in ART initiation in a representative sample of 4154 HIV-infected people who started ART in Cameroon between 2007 and 2010.Findings
In Cameroon, the median CD4+ cell counts at ART initiation increased from 140 cells/μl (interquartile range, IQR: 66 to 210) in 2007–2009 to 163 cells/μl (IQR: 73 to 260) in 2010. The estimated average time from seroconversion to ART initiation decreased from 10.4 years (95% confidence interval, CI: 10.3 to 10.5) to 9.8 years (95% CI: 9.6 to 10.0). Delay in ART initiation increased from 3.4 years (95% CI: 3.1 to 3.7) to 5.8 years (95% CI: 5.6 to 6.2).Conclusion
The estimated time to initiate ART and the delay in ART initiation indicate that progress in Cameroon is insufficient. These indicators should help monitor whether public health interventions to accelerate ART initiation are successful. 相似文献59.
60.
Li G Hu Y Yang W Jiang Y Wang J Xiao J Hu Z Pan X Howard BV Bennett PH;DA Qing IGT Diabetes Study 《Diabetes research and clinical practice》2002,58(3):193-200
OBJECTIVE: To investigate the effects of insulin resistance (IR) and insulin secretion (IS) on the development of diabetes mellitus in individuals with impaired glucose tolerance (IGT) who underwent lifestyle interventions. METHODS: 284 out of 577 individuals with IGT identified by population-based screening in Da Qing, China, who were randomized to undergo diet change and/or increased physical activity had baseline fasting and 2 h post-load insulin determinations. They were followed for 6 years for the development of diabetes. IR and IS were assessed using calculated indices based on fasting plasma insulin and glucose. The interactions of IR, IS, obesity and plasma glucose and the effects of the lifestyle interventions were evaluated using Cox Proportional Hazards analysis. RESULTS: Both IR and IS were significantly associated with the development of diabetes. Lifestyle interventions were more effective in those with lower IT and higher IS at baseline. Diet plus exercise interventions resulted in significantly lower incidence of diabetes, even after controlling for IR, IS, BMI and 2hrPG. CONCLUSION: Both IR and beta-cell function were predictors of diabetes in Chinese with IGT. Lifestyle intervention reduced the incidence of DM and these interventions were more effective in those with less IR. 相似文献