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91.
92.
Aim: Circulating immune cell activation is associated with worse outcome in adult and animal models of brain injury. Our aim was to profile the systemic inflammatory response over the first week of life in infants at risk of neonatal encephalopathy (NE) and correlate early neutrophil and monocyte endotoxin and activation responses with outcome.

Methods: Prospective observational study in a tertiary referral university hospital including 22 infants requiring resuscitation at birth who had serial (five time points) neutrophil and monocyte CD11b (marker of cell adhesion), intracellular reactive oxygen intermediates (ROI; cell activation) and Toll-like receptor (TLR; endotoxin recognition) before and after endotoxin stimulation ex vivo compared to neonatal controls.

Results: All neonates requiring resuscitation at delivery (n?=?122 samples) had higher neutrophil and monocyte CD11b and TLR-4 expression compared with adults and neonatal controls. Neonates with abnormal neuroimaging and/or severe NE had increased CD11b, ROI and TLR-4. Increased polymorphonuclear leukocytes TLR-4 expression was associated with increased mortality in infants with NE.

Conclusion: Innate immune dysregulation in the first week of life is associated with severity of outcome in neonatal brain injury in this cohort and may be amenable to immunomodulation.  相似文献   
93.
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   
94.
95.
郑武  笪琴  张薇  汤恒  彭国平 《实用预防医学》2018,25(11):1325-1328
目的 分析湖北省接受艾滋病HAART患者CD4+T淋巴细胞变化趋势及影响因素。 方法 筛选2012年1月1日以后接受HAART的成年患者,利用一般线性模型、重复测量方差分析来分析患者的基线、治疗后6、12个月的CD4+T淋巴细胞计数情况及影响因素。 结果 1 843例研究对象基线CD4+T淋巴细胞计数均值为(218.94±143.96)个/μl,接受HAART后6个月为(334.31±188.62)个/μl,12个月后为(382.79±204.44)个/μl,差异有统计学意义(F=6 856.98,P=0.000)。影响HAART治疗后CD4+T淋巴细胞计数上升的主要因素是:性别、开始治疗年龄、WHO临床分期、初始治疗方案、基线CD4+T淋巴细胞计数。受性别、基线CD4+T淋巴细胞计数、开始治疗年龄、初始治疗方案等影响,治疗后CD4+T淋巴细胞计数随时间推移呈线性上升趋势;其中,女性、开始治疗年龄越小、基线CD4+T淋巴细胞计数越高、初始治疗方案含二线药物的患者上升较快。受WHO临床分期因素影响,治疗后CD4+T淋巴细胞计数随时间推移上升趋势符合二次方曲线方程,WHO临床分期越靠前,上升速度较快。 结论 湖北省艾滋病患者接受HAART后CD4+T淋巴细胞计数上升受多种因素影响,建议针对不同的患者及早开展HAART,提高抗病毒治疗的效果和患者生命质量。  相似文献   
96.
The purpose of this study was to develop a technique to evaluate the implant-abutment gap of an external hexagon implant system as a function of radius. Six implants of 3.75 mm in diameter (Conexao Sistema de Protese Ltda, Sao Paulo, Brazil) and their respective abutments were screw connected and torqued to 20 N cm(-1). The implants were mounted in epoxy assuring an implant long-axis position perpendicular to the vertical axis. Each implant was grounded through its thickness parallel to implant long-axis at six different distance interval. Implant-abutment gap distances were recorded along the implant-abutment region for each section. Individual measurements were related to their radial position through trigonometric inferences. A sixth degree polynomial line fit approach determined radial adaptation patterns for each implant. Micrographs along implant sections showed a approximately 300 mum length implant-abutment engagement region. All implants presented communication between external and internal regions through connection gaps and inaccurate implant-abutment alignment. Average gap distances were not significantly different between implants (P > 0.086). Polynomial lines showed implant-abutment gap values below 10 mum from 0 mum to approximately 250 mum of the implant-abutment engagement region. Gap distances significantly increased from approximately 250 mum to the outer radius of the implant-abutment engagement region. The technique described provided a broader scenario of the implant-abutment gap adaptation compared with previous work concerning implant-abutment gap determination, and should be considered for better understanding mechanical aspects or biological effects of implant-abutment adaptation on peri-implant tissues.  相似文献   
97.
目的 探讨合成一种西地那非类似物的新方法.方法 设计以WG 001-01-08和五硫化二磷为原料,经过硫化得到目标化合物(一种西地那非类似物)的合成路线,并以收率和杂质为指标考察反应试剂、反应温度、加料顺序对反应的影响.结果 成功制备了目标化合物,收率为90%;较佳反应条件为以4-甲基吡啶为溶剂,120℃反应4h,先加WG001-01-08后加五硫化二磷.结论 新方法收率较高,杂质少,反应条件温和,适合工业化生产.  相似文献   
98.
目的:比较自体外周血干细胞移植(APBSCT)与自体骨髓移植治疗CR1期急性髓性白血病(AML)的临床疗效。方法:用APBSCT治疗AML患者27例,用非净化自体骨髓移植(ABMT)治疗AML患者13例,用净化自体骨髓移植(PABMT)治疗AML患者25例。结果:(1)APBSCT组造血重建校其他两组显著加快;(2)APBSCT组的3年无病生存率(DFS)和复发率(RR)分别为51.%和42.2%,与ABMT组的46.2%、46.7%相当,但与净化ABMT组的72.9%、23.7%相比差异有显著性意义。(3)三组的移植相关死亡率(TRM)差异无显著性意义,死亡的主要原因为感染和内脏出血。结论:APBSCT治疗CR1期AML,其造血重建显著快于ABMT,其疗效与ABMT相当,而显著低于PABMT。  相似文献   
99.
The efficacy of immunomagnetic beads to purge human myeloma cells from bone marrow ex vivo was evaluated. The optimal conditions for purging were studied first by using three myeloma cell lines: RPMI-8226, SKO- 007, and SKMM-2. Myeloma cells labeled with the vital fluorescent dye Hoechst 33342 were admixed with normal bone marrow cells, and two monoclonal antibodies reactive with the myeloma cells (PCA-1 and BL-3) were added alone or in combination with the cells. Magnetic beads coated with goat antimouse immunoglobulin G were then added, and the tumor cells to which beads were attached were separated from the mixture with a magnet. The efficacy of tumor cell removal was dependent on the bead-to-tumor ratio; a ratio of more than 500 was optimal in the presence of excess normal marrow cells. The combination of monoclonal antibodies PCA-1 and BL-3 increased the tumor cell removal as compared with either antibody alone. Two cycles of treatment were more effective than one cycle was. Under optimal conditions, 2.3 to 4 logs of tumor cells could be removed from the mixture containing 10% myeloma cells without a significant loss of normal hematopoietic progenitors as measured by CFU-GM, CFU-GEM, and BFU-E. When the efficacy of this procedure was tested on fresh bone marrow from patients with multiple myeloma (MM) by using the combination of PCA-1, BL-3, and J-5, 1.6 to 2.5 logs of tumor cells could be removed by one cycle of treatment, even from marrows containing less than 10% myeloma cells. These observations support the use of monoclonal antibody combinations and immunobeads as a reliable and nontoxic method to eliminate contaminating myeloma cells ex vivo in preparation for autologous bone marrow transplantation in patients with MM.  相似文献   
100.
Oxidative metabolism of the human eosinophil   总被引:14,自引:1,他引:14  
We have compared the oxidative metabolism of human eosinophils (80%-90% purity) to that of neutrophils. Hexose monophosphate (HMP) shunt activity of eosinophils was higher than that of neutrophils under either resting or phagocytizing conditions. Eosinophil HMP shunt activity also was stimulated by phorbol myristate acetate, a membrane- active agent. Eosinophils showed a marked incorporation of 125I into trichloroacetic acid-insoluble material under resting conditions, which increased markedly during phagocytosis. Eosinophils likewise showed a greater reduction of nitroblue tetrazolium dye during phagocytosis than did neutrophils. Measurement of other parameters of oxidative metabolism indicated that eosinophils generated superoxide anion following phagocytosis and also elicited a burst of chemiluminescence similar to that observed during phagocytosis by neutrophils. Measurement of NADPH oxidase activity demonstrated that this enzyme was 3-6 times more active in fractions isolated from eosinophils than in corresponding fractions isolated from neutrophils; this was observed over a range of substrate concentrations. The eosinophil enzyme sedimented differently than the neutrophil enzyme with differential centrifugation; neither showed sedimentation characteristics of peroxidase. These data indicate that eosinophils possess a similar, although in some ways more potent, oxidative burst than neutrophils and are consistent with a role for NADPH oxidase in the initiation of that burst.  相似文献   
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