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101.
JH Raphael JL Southall TV Gnanadurai GJ Treharne GD Kitas 《BMC musculoskeletal disorders》2002,3(1):17-8
Background
Continuous intrathecal drug delivery has been shown in open studies to improve pain and quality of life in those with intractable back pain who have had spinal surgery. There is limited data on long term effects and and even less for patients with mechanical back pain without prior spinal surgery. 相似文献102.
电化学方法研究环丙沙星及其镁、锰络合物与脱氧核糖核酸的相互作用 总被引:3,自引:0,他引:3
用电化学的方法,研究环丙沙星(CPFX)及其镁、锰络合物与脱氧核糖核酸(DNA)的相互作用及其极谱伏安行为。结果在0.1mol·L-1NH3-NH4Cl(pH9.2)溶液中,环丙沙星可与DNA作用,产生一新的极谱峰 Ep=-1.72V(vsAg/AgCl),在有Mg2+或Mn2+存在时则生成三元络合物,产生一电位更负的新峰,峰电位Ep=-1.78V,提示Mg2+或Mn2+离子参与药物与DNA的作用。对它们的还原峰性质研究表明,电极还原反应是完全不可逆的,电流具有吸附性。本文还探讨了电极还原机理,认为参与电极还原的是三元络合物中的环丙沙星分子,进一步推测CPFX-Mg是嵌入DNA的双螺旋结构中。 相似文献
103.
多索茶碱在大鼠体内的药代动力学 总被引:1,自引:0,他引:1
为全面了解多索茶碱在大鼠体内代谢情况,用高效薄层色谱法和光密度扫描法,给大鼠ig多索茶碱后,测定在不同时间各组织和体液中多索茶碱的含量。结果表明,多索茶碱在大鼠体内药代动力学为一室模型并能在体内迅速转化为其它代谢产物。T1/2(Ke)为1.17~3.75h,达峰时间T(peak)为0.72~1.46h,Cmax,AUC及CL/F呈剂量依赖关系。给药1h,以胃壁浓度最高,8h除胃肠组织浓度降低较慢外,其它组织中药物浓度明显降低。尿、粪及胆汁中原形药总排出量占给药量的5.2%。血浆蛋白结合率约25%。提示多索茶碱在体内可能转化为其它代谢产物。 相似文献
104.
Daniel Kotz Geertjan Wesseling Marcus JH Huibers Onno CP van Schayck 《BMC public health》2007,7(1):332
Background
The use of spirometry for early detection of chronic obstructive pulmonary disease (COPD) is still an issue of debate, particularly because of a lack of convincing evidence that spirometry has an added positive effect on smoking cessation. We hypothesise that early detection of COPD and confrontation with spirometry for smoking cessation may be effective when applying an approach we have termed "confrontational counselling"; a patient-centred approach which involves specific communication skills and elements of cognitive therapy. An important aspect is to confront the smoker with his/her airflow limitation during the counselling sessions. The primary objective of this study is to test the efficacy of confrontational counselling in comparison to regular health education and promotion for smoking cessation delivered by specialized respiratory nurses in current smokers with previously undiagnosed mild to moderate airflow limitation. 相似文献105.
目的:比较C17.2神经干细胞和NURR1基因修饰的C17.2神经干细胞移植治疗对脑梗死模型鼠神经功能缺损的改善效果,观察细胞移植后与宿主脑组织的整合、存活、移行及分化情况。方法:实验于2005-06/12在中山大学附属第二医院林百欣实验中心完成。①实验材料:选取清洁级健康SD雄性大鼠78只,随机数字表法分为模型对照组、神经干细胞组、转基因神经干细胞组,26只/组。条件永生化神经干细胞系C17.2由哈佛大学儿童医院Even Synder教授惠赠。pAdeasy-NURR1重组复制缺陷性腺病毒由本实验室成功构建。Dil18荧光染料(Chemicon公司产品)。②实验方法:收集C17.2神经干细胞和pAdeasy-NURR1 C17.2神经干细胞,各分为两管,一管加入Dil18荧光示踪剂。各组大鼠均采用线栓法建立局灶性脑缺血/再灌注损伤模型,3d后进行细胞移植,以江湾Ⅱ型脑立体定向仪进行立体定位,选择缺血半暗区3个位点为移植区:前囟头侧1mm,旁开2mm,深度1.2mm;前囟尾侧3mm,旁开1.5mm,深度1.2mm;前囟尾侧6mm,旁开2mm,深度1.2mm。模型对照组每位点注射单纯培养液2μL;神经干细胞组取6只每位点移植Dil18标记的C17.2神经干细胞悬液2μL,剩余20只每位点移植C17.2神经干细胞悬液2μL;转基因神经干细胞组取6只每位点移植Dil18标记的pAdeasy-NURR1 C17.2神经干细胞悬液2μL,余20只每位点移植pAdeasy-NURR1 C17.2神经干细胞悬液2μL。③实验评估:各组大鼠分别在移植前1d及移植后1周、2周、1个月进行神经功能缺损评分。移植后1周、2周、1个月进行荧光示踪检查及神经元特异烯醇化酶免疫组化检测。移植后6个月行组织学检查。结果:移植后1周,模型对照组死亡1只,神经干细胞组死亡2组,转基因神经干细胞组死亡2只,均淘汰并予以补充。①神经功能缺损评分:移植前1d各组大鼠神经功能缺损评分基本相似(P>0.05)。移植后1周、2周、1个月神经干细胞组、转基因神经干细胞组神经功能缺损评分均明显低于模型对照组(P<0.05);转基因神经干细胞组下降趋势较神经干细胞组更为显著(P<0.05)。②Dil18荧光细胞示踪结果:移植后1周荧光示踪细胞主要在针道内,少数细胞开始移行至周围神经组织。移植后2周,细胞移行至更远距离,并明显向梗死灶方向移行,细胞有突触样结构与周围细胞形成联系。移植后1个月细胞向周围扩散,甚至在远隔部位也可见荧光细胞。③神经元特异烯醇化酶免疫组化检测结果:移植后2周、1个月,转基因神经干细胞组神经元特异烯醇化酶阳性细胞数均明显高于神经干细胞组(P均<0.05)。④细胞组织学检查:移植后6个月,各组大鼠注射针道周围脑组织仍呈正常的层次和结构,未见有明显异型细胞增生。结论:①NURR1基因修饰的C17.2神经干细胞移植治疗局灶性脑梗死能显著改善神经功能缺损,效果优于C17.2神经干细胞。②移植后供体细胞存活并向注射针道周围神经组织移行,促进神经干细胞向神经元方向的分化。 相似文献
106.
The clinical spectrum of postpartum thyroid disease 总被引:1,自引:0,他引:1
Lazarus JH; Hall R; Othman S; Parkes AB; Richards CJ; McCulloch B; Harris B 《QJM : monthly journal of the Association of Physicians》1996,89(6):429-435
The clinical and biochemical features of postpartum thyroid disease were
analysed in 152 antithyroid peroxidase antibody-positive (anti TPO+ve)
women and compared with 239 anti-TPO-ve age-matched control postpartum
women. All were assessed monthly for up to 12 months postpartum. Seventy
three anti-TPO+ve women developed post-partum thyroiditis (PPT): 19.2%
hyperthyroid alone, 49.3% hypothyroid alone, and 31.5% characterized by
hyper- followed by hypothyroidism. None of the antibody-negative women
developed any thyroid dysfunction. A significant increase in many of eleven
symptoms of hypothyroidism and some of eight symptoms of hyperthyroidism
compared to control women was observed in all anti-TPO+ve women,
independent of thyroid status. This was particularly seen in women who
later developed PPT when they were euthyroid, but was also observed in
euthyroid anti-TPO+ve women who showed no decline of thyroid function
during the postpartum period. Although PPT is usually transient, this
condition, and the euthyroid antibody-positive state, may be associated
with significant symptomatology, including an increased incidence of minor
to moderate depression. Early recognition of this syndrome by antenatal
screening of thyroid antibodies may contribute to improved management of
women during the postpartum period.
相似文献
107.
108.
109.
Monocyte‐derived dendritic cells can induce autoreactive CD4+ T cells showing myeloid lineage directed reactivity in healthy individuals 下载免费PDF全文
Tin Sing Lam Marian van de Meent JH Frederik Falkenburg Inge Jedema 《European journal of immunology》2015,45(4):1030-1042
T cells against self‐antigens can be detected in peripheral blood of healthy individuals, although intrathymic negative selection removes most high‐avidity T cells specific for self‐antigens from the peripheral repertoire. Moreover, spontaneous T‐cell proliferation following stimulation with autologous monocyte‐derived dendritic cells (autoDCs) has been observed in vitro. In this study, we characterized the nature and immunological basis of the autoDC reactivity in the T‐cell repertoire of healthy donors. We show that a minority of naive and memory CD4+ T cells within the healthy human T‐cell repertoire mediates HLA‐restricted reactivity against autoDCs, which behave like a normal antigen‐specific immune response. This reactivity appeared to be primarily directed against myeloid lineage cells. Although cytokine production by the reactive T cells was observed, this did not coincide with overt cytotoxic activity against autoDCs. AutoDC reactivity was also observed in the CD8+ T‐cell compartment, but this appeared to be mainly cytokine‐induced rather than antigen‐driven. In conclusion, we show that the presence of autoreactive T cells harboring the potential to react against autologous and HLA‐matched allogeneic myeloid cells is a common phenomenon in healthy individuals. These autoDC‐reactive T cells may help the induction of primary T‐cell responses at the DC priming site. 相似文献
110.
The nuclear enzyme terminal deoxynucleotidyl transferase (TdT) is thought to contribute to the diversity of certain immunoglobulin and T cell receptor gene rearrangements through the addition of random nucleotides at their variable (V)-joining (J) region junctions. An acute lymphoblastic leukemia (ALL) with an immature T cell phenotype (CD7+, CD5+, CD1+/-, CD2+/-, CD3-, CD4-, CD8-) was found to be TdT+ with germline immunoglobulin heavy chain, T cell receptor beta chain, and T cell gamma chain genes. The data indicate that TdT expression can precede T gamma and T beta rearrangement during T lymphoid ontogeny consistent with its proposed association with the T cell receptor rearrangement process. Southern analysis of certain cases of T-ALL may not result in the detection of a monoclonal population of cells. 相似文献