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81.
BACKGROUND: The role of inflammation in the pathogenesis of cardiovascular disease is well established. C-reactive protein (CRP) is the strongest independent predictor of myocardial infarction and stroke in women. Recent studies have indicated that CRP levels are raised during use of combined oral contraceptives (COCs). OBJECTIVES: The aim of the study was to investigate the effect of COCs on serum CRP levels and to indicate the underlying mechanisms of an expected increase. METHOD: In a prospective randomized cross over-study 35 women used two different preparations of COC, one second and one third generation. Serum levels of CRP, serum amyloid A (SAA), interleukin-6 (IL-6), tumor necrosis factor alpha (TNFalpha), antibodies against oxidized LDL, insulin and insulin-like growth factor-I (IGF-I) along with insulin-like growth factor binding protein-1 (IGFBP-1) and IGFBP-3 were analyzed before and during the two treatments. E-selectin, von Willebrand factor and factor VIII concentrations in plasma were also measured. RESULTS: A rise in serum CRP was observed during both treatments; the median level increased from 0.45 mg L(-1) at baseline to 1.48 mg L(-1) with second generation and to 2.02 mg L(-1) with third generation COC. The serum levels of SAA increased slightly during treatment with the third generation COC. IL-6 and TNFalpha were unaffected by treatment. Both preparations lowered IGF-I and raised IGFBP-1 and IGFBP-3 concentrations. CONCLUSION: The raised serum CRP concentration during treatment with COCs appears to be related to a direct effect on hepatocyte CRP synthesis and does not reflect IL-6 mediated inflammation, endothelial activation or induction of insulin resistance.  相似文献   
82.
目的探讨抑肽酶对二尖瓣置换术患者围体外循环(CPB)期心肌细胞及心肌血管内皮细胞上细胞间粘附分子-1(ICAM-1)、血管细胞粘附分子-1(VCAM-1)表达及心肌细胞凋亡的影响。方法择期二尖瓣置换术患者30例,年龄24~59岁,体重46~73 kg,心功能分级Ⅱ级或Ⅲ级,随机分为2组(n=15):对照组和抑肽酶组,抑肽酶组于CPB转机前,预充液中加入抑肽酶300万KIU,对照组则给予等容量生理盐水,分别于CPB前和CPB停止时取右心房心肌组织标本,采用免疫组织化学SP法染色,检测心肌细胞和心肌血管内皮细胞上ICAM-1、VCAM-1的表达,采用病理图像分析系统对ICAM-1、VCAM-1表达的灰度值作定量分析,采用TUNEL法检测凋亡心肌细胞。结果抑肽酶组CPB停止时ICAM-1、VCAM-1的表达低于对照组(P〈0.01);2组CPB停止时心肌细胞凋亡指数较CPB前增高(P〈0.05),抑肽酶组CPB停止时心肌细胞凋亡指数低于对照组(P〈0.05)。结论预充液中加入抑肽酶300万KIU可抑制二尖瓣置换术患者CPB期间心肌细胞和心肌血管内皮细胞ICAM-1、VCAM-1的表达及心肌细胞的凋亡。  相似文献   
83.
Cytostatic as well as cytotoxic effects of tumour necrosis factor alpha (TNF-α) therapy have been shown in vitro and in experimental in vivo models. Nevertheless, the mechanism of anti-tumour activity in humans in vivo remains unclear. To determine the role of the vascular lining endothelial cells as important mediators of several immunological interactions, we investigated changes in the levels of the soluble endothelial cell adhesion molecules intercellular adhesion molecule 1, E-selectin and vascular cell adhesion molecule 1 as well as of soluble TNF receptors I and II during systemic therapy with recombinant human rhTNF-α (rhTNF-α). All tests were performed by enzyme-linked immunosorbent assays (ELISAs). The clinical efficacy of the intravenous rhTNF-α therapy was poor. Only one patient with isolated intra-arterial limb perfusion had a delayed, marked, but only temporary necrosis of tumour cells. In contrast, we found a marked, significant and (during therapy) undulating augmented increase in the levels of soluble adhesion molecules as well as of the soluble TNF receptors. Taken together, these data support the hypothesis that a sufficient tumour-specific cellular immunity is required to achieve a clinically apparent efficacy of systemic rhTNF-α therapy in addition to cytokine-dependent inducible activation mechanisms. In this context, the vascular lining endothelial cells might play an important role as mediators of the complex immunological antitumoral activity.  相似文献   
84.
目的探讨微波热凝切割睑球粘连的治疗效果。方法随机抽取1995年1月~1997年12月我科应用微波治疗睑球粘连22例进行回顾性总结。结果22例轻、中、重度睑球粘连患者,经1~4次热凝切割,均痊愈。结论微波技术切割睑球粘连操作简便易行,是一种较为理想的治疗方法。  相似文献   
85.
Summary: A case of early epileptic encephalopathy (EIEE) with suppression-bursts or Ohtahara's syndrome, associated with focal cortical dysplasia is reported. Infantile spasms and brief tonic unilateral seizures began on the fifth day of life. Interictal EEG demonstrated an asymmetrical "suppression-burst" pattern with no wake or sleep cycling. Seizures were refractory to all antiepileptic drug (AED) and steroid therapy. Magnetic resonance imaging (MRI) showed right frontotemporal cortical thickening. After three weeks of an ineffective medical treatment a preoperative evaluation with single photon emission computed tomography (SPECT) and electrocorticography (ECoG) was performed to characterize epileptogenic focus. Surgical resection of the precentral area was performed at age 1 month. Neuropathologic examinations confirmed diagnosis of focal cortical dysplasia by identifying cytoarchitectural disarray and ectopic neurons located deep in subcortical white matter. During follow-up, 1-year postoperative the child had a single febrile seizure. Neurologic examination showed minor developmental delay and slight left-sided weak ness.  相似文献   
86.
Rhombencephala from rat embryos were processed as whole-mounts for immunocytochemical detection of monoaminergic cell populations, using antibodies to tyrosine hydroxylase (TH) and serotonin (5-HT). Specific advantages of the whole-mount technique over the classical serial-section method were that even isolated immunoreactive (IR) cells could be detected easily, and three-dimensional relationships could be ascertained without the need for serial reconstruction. Embryos between embryonic days (E) 12 and 16 (the day following nocturnal mating being considered as E1) were used in this study. Both TH and 5-HT immunoreactivities were already detectable at E12, even in the smallest embryos (crown-rump length: 6 mm), but there was a striking difference in the number and regional distribution of these two types of IR cells. TH was expressed in several cell groups located in the rostral rhombencephalon (the presumed anlage of the A4-7 complex) as well as in the caudal rhombencephalon (the presumed anlagen of groups A1-2 and C1-3), whereas 5-HT was expressed in very few cells located near the rostral border of the rhombencephalon (presumed anlage of the B4-9 complex). Although the three-dimensional distribution of the TH-IR cell groups underwent some modifications during the period studied, its general pattern remained relatively stable after E12. This contrasted with the sequential appearance of the 5-HT-IR cell groups and their spatial transformations during this period. Using the rhombencephalic isthmus as a landmark, we found that conspicuous 5-HT-IR fibre bundles penetrated into the mesencephalon from E13 onwards, but that the 5-HT IR cell bodies were exclusively located caudal to the borderline between the mesencephalon and the rhombencephalon (the rhombencephalic isthmus). We therefore suggest the term "rostral rhombencephalic raphe nuclei" for the rostral 5-HT cell groups instead of "mesencephalic raphe nuclei," which is a misnomer. Close spatial association between TH and 5-HT-IR elements was observed mainly in the caudal rhombencephalon, where 5-HT-IR fibres coursed through an area containing numerous TH-IR cell bodies (the presumed anlagen of groups A1-2 and C1-3).  相似文献   
87.
目的 探讨癌胚抗原相关细胞黏附分子(CEACAM1)源性多肽KM17对血小板聚集、释放、黏附功能的影响。方法 采用血小板聚集仪观察多肽KM17对凝血酶、胶原、花生四烯酸(AA)、二磷酸腺苷(ADP)等激动剂诱导的血小板聚集的影响;流式细胞术观察多肽KM17对ADP激活血小板后P-选择素释放的影响;显微镜下观察多肽KM17对血小板静态黏附于胶原基质的影响。结果 多肽KM17能显著促进ADP诱导的血小板聚集且呈剂量依赖(P <0.05),而对AA、胶原及凝血酶诱导的血小板聚集差异均无统计学意义(P>0.05);此外,多肽KM17对ADP激活血小板后P-选择素释放及血小板静态黏附于胶原基质的差异也无统计学意义(P>0.05)。结论 多肽KM17可明显促进ADP诱导的血小板聚集,但对ADP活化血小板后P-选择素释放及血小板静态黏附于胶原基质未见明显作用。  相似文献   
88.
活动性类风湿关节炎患者sICAM-1、sVCAM-1的变化及意义   总被引:2,自引:0,他引:2  
目的 :测定活动性类风湿关节炎 (RA)患者血清中sICAM 1、sVCAM 1水平 ,探讨sICAM 1、sVCAM 1与IL 1、TNF、IFN γ及病情的关系。方法 :用酶联免疫分析法 (ELISA)检测 30例活动性RA患者与 30例健康对照者sICAM 1、sVCAM 1、IL 1、TNF、IFN γ水平。结果 :RA患者血清sICAM 1、sVCAM 1、IL 1、TNF、IFN γ水平明显高于正常对照组 (P<0 0 0 1) ,sICAM 1与IL 1、IFN γ正相关 ,与RF亦呈正相关 ,sVCAM 1与IL 1、TNF、IFN γ正相关 ,与ESR、CRP、Stock指数正相关。结论 :RA患者血清sI CAM 1、sVCAM 1水平显著升高 ,sICAM 1、sVCAM 1可能参与RA发病过程 ,sICAM 1可作为判断病情严重性的指标 ,sVCAM 1可作为观察病情活动性的指标。  相似文献   
89.
目的 :通过测定妊高征 (PIH)患者红细胞免疫粘附 (RCIA)调节因子活性 ,探讨PIH患者红细胞免疫功能改变的原因。方法 :测定 40例PIH患者和 30例正常孕妇的RCIA促进因子活性和抑制因子活性及红细胞补体受体花环率(RBCC3bRR% )、红细胞免疫复合物花环率 (RBCICR % )。结果 :与正常孕妇相比 ,PIH患者RCIA抑制因子活性明显升高 ,RBCC3bRR%及RBCICR %明显降低 (P <0 .0 1) ,RCIA促进因子活性无明显变化 (P >0 .0 5 )。结论 :PIH患者红细胞免疫功能原发低下 ,其原因可能与RCIA抑制因子活性增高有关  相似文献   
90.
Synergistic interactions between cytokines, chemokines and adhesion molecules may facilitate the selective recruitment of eosinophils into sites of allergic inflammation. Ovalbumin-sensitized IL5TG mice responded to antigen challenge with robust airway eosinophilia 24 and 72 hr post-exposure. Adhesion molecule expression and functional responsiveness of immune cells derived from IL5TG mice to various inflammatory mediators were evaluated. IL5TG-derived eosinophils, but not neutrophils, expressed higher levels of CD49d and CD11b relative to WT. Functional responsiveness to eotaxin was increased in IL5TG eosinophils as demonstrated by a 10× increase in its potency in producing actin polymerization and 3× increase in CD11b upregulation relative to WT. These data are consistent with increased CCR3 expression on IL5TG eosinophils. Responsiveness of eosinophils to LTB4 or MIP-1 was similar between WT and IL-5TG mice. These data provide evidence of synergy between eosinophil-specific cytokines and chemokines that may promote accumulation of this cell type under conditions of allergic inflammation in vivo.  相似文献   
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