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91.
Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a genetically transmitted cerebrovascular disease. Typically, the first clinical manifestation is migraine and the full clinical spectrum of the disease with recurrent strokes of the subcortical type, cognitive, and mood disorders is seen during the fourth and fifth decades of life. Vascular risk factors are usually absent in CADASIL patients and the diagnosis of the disease is particularly suspected in young adults with cerebrovascular events of unknown cause, diffuse leukoencephalopathy on computed tomography or magnetic resonance imaging, and a history of cerebrovascular diseases or dementia in many family members. We describe three Italian CADASIL patients who presented to medical attention for cerebrovascular events occurred after the age of 55 and had, in addition to hypertension and hyperlipidemia, thrombophilic risk factors such as hyperhomocysteinemia, elevated levels of lipoprotein(a), and antiphospholipid antibodies. Symptoms possibly related to cortical involvement, such as dysphasia and visual field deficits, were reported by two of these patients. We conclude that a diagnosis of CADASIL should not be disregarded in patients with vascular risk factors and presenting with symptoms not immediately referable to subcortical damage at ages more advanced than commonly reported.  相似文献   
92.
A conformationally biased, agonist of human C5a65–74 (EP67) was assessed for its adjuvant activities in vitro and in vivo. EP67 induced the release of the inflammatory (Th1) type cytokines from C5a receptor (CD88)-bearing antigen presenting cells (APC). EP67 did not induce the release of these cytokines from splenic APCs obtained from C5a receptor knockouts (CD88−/−). Serum from mice immunized with EP67–ovalbumin (OVA) contained high OVA-specific antibody (Ab) titers [IgG1, IgG2a (IGg2c), IgG2b]. Mice receiving OVA alone produced only IgG1 Abs, indicating the ability of EP67 to induce a Th1-like Ab class switch. Spleen cell cultures from wild type mice but not CD88−/− mice showed an enhanced OVA-specific proliferative response in vitro. These results indicate the ability of EP67 to drive a Th1-mediated immune response and its potential use as a unique adjuvant.  相似文献   
93.
Splanchnic ischaemia and its role in multiple organ failure   总被引:3,自引:0,他引:3  
Multiple organ failure remains the leading cause of death in the intensive care unit. Increasing numbers of investigators have focused their attention on the role of gastrointestinal tract in the pathogenesis of this syndrome. Their data indicate that inadequate gut perfusion leads to a measurable imbalance between oxygen delivery and the needs of the tissues, i.e., ischaemia. Gut ischaemia of sufficient duration impairs gastrointestinal tract barrier function, facilitating the passage of enteric bacterial endotoxin into the circulation. It has been hypothesized that production of tumor necrosis factor α, and other biologic mediators by endotoxin–stimulated macrophages, triggers a generalized and uncontrolled inflammatory response that ultimately leads to multiple organ failure.
Preliminary evidence suggests that survival can be improved significantly if gut ischaemia is promptly identifed and aggressively treated by administration of fluids and inotropic drugs, using gastric intramucosal pH as the therapeutic endpoint. Future studies are needed to determine whether additional treatment modalities can improve outcome once the inflammatory response has fully developed.  相似文献   
94.
目的 研究冠心病患者心肌缺血情况下循环中白细胞介素-6(IL-6)和脂蛋白(a)[LP(a)]水平的关系和临床意义。方法 用ELISA分析试剂盒检测62例冠心病患者和50例健康对照者血浆IL-6,用免疫透射比浊法检测血滑LP(a),并对心电图(EKG)ST段的情况进行比较。结果 冠心病组血浆IL-6和血清LP(a)水平均较健康对照组显著增高(P<0.01)。与健康对照组相比,ST段异常组和ST段正常组血浆IL-6水平均显著增高(P<0.01);ST段异常组血浆LP(a)水平显著增高(P<0.01),ST段正常组血清LP(a)水平有所增高,但无统计学意义(P>0.05)。ST段异常组血浆IL-6和血清LP(a)水平均显著高于ST段正常组(P<0.05,P<0.01)。冠心病患者血浆IL-6和血滑LP(a)水平存在显著的相关性(P<0.05)。结论 冠心病患者循环中IL-6和LP(a)水平显著升高,高水平IL-6和LP(a)可能反映血管和心肌损伤的发生,LP(a)的增加可能与IL-6刺激肝脏合成LP(a)增加有关。  相似文献   
95.
目的 :了解活化血小板葡萄糖摄取过程及血小板膜整合素对其影响 ,探讨整合素与血小板能量代谢的关系 ,旨在研究血小板能量代谢涉及的信号传导 ,并为目前临床应用血小板膜糖蛋白Ⅱb/Ⅲa(GPⅡb/Ⅲa)单抗抗血小板活化提供新的理论依据。方法 :用液态闪烁计数方法检测在血小板膜糖蛋白Ⅱb/Ⅲa单抗 10E5及血小板整合素αυβ3 单抗 6 0 9干预与否情况下凝血酶激活后血小板摄取氚标 2 脱氧葡萄糖 ([3 H]2 DG)率。结果 :在生理浓度范围内活化血小板 [3 H]2 DG摄取率较静息时明显升高 ,单抗 10E5可充分阻断活化血小板葡萄糖摄取 ,单抗 6 0 9可部分阻断。结论 :整合素家族单抗可抑制血小板激活后葡萄糖摄取 ,提示其可能参与血小板能量代谢信号传导过程 ,并可能以GPⅡb/Ⅲa为主  相似文献   
96.
Background Although neutrophils have been implicated in bronchial asthma, the mechanism(s) which bring these cells into the airways is poorly understood. Objective To investigate the presence and identity of neutrophil chemotactic factors in bronchoalveolar lavage (BAL) fluid from atopic asthmatic subjects. Method BAL fluid was obtained from 13 subjects (seven asthmatics and six normals). aged 19 to 60 yr, at bronchoscopy. Separation of neutrophil chemotactic activity (NCA) was achieved by FPLC cation exchange chromatography. Fractions were collected and assayed for chemotaxis multiwell micro-chemotaxes chambers using polycarbonate filters, for the complement peptide C5a/C5a des Arg by radioimmunoassay (RIA) and for interleukin-8 (IL-8) by ELISA. Results NCA was found in FPLC fractions of BAL samples in four out of seven asthmatics and each of these subjects had at least three similar peaks of NCA. The major peak of NCA was found to contain immunoreactive C5a/C5a des Arg and chemotaxis. In response to this NCA could be blocked by desensitization of the neutrophils with recombinant C5a. Purified serum derived C5a/C5a des Arg was found to have altered chromatographic properties when added to BAL fluid; this suggested that BAL fluid contained proteins which interacted with the C5a/C5a des Arg. Immunoreactive IL-8 (iIL-8) was also detected but its concentration or chemical form was insufficient to induce neutropbil chemotaxis. Conclusion This study demonstrates that bronchial asthmatic lavage fluid contains C5a/C5a des/Arg and iL-8, together with other as yet unidentified factors which may contribute to neutropbil recruitment in this disease.  相似文献   
97.
在建设学习型社会和新课改的新形势下,高中生物教师应确立三种意识:"学习意识、信息意识、科研意识",不断提高自身素质,使自己成为一名学者型、研究型的现代生物教师.  相似文献   
98.
99.
研制了可以直接连续测量大鼠游泳输出功率的仪器,建立了一个理想的动物模型,通过分析对功率曲线进行函数拟合,得出了代表疲劳发生、作功能力下降的双曲线方程,通过分析衰竭时间和功、功率等参数的关系提出了衰竭阈概念。  相似文献   
100.
抗肿瘤药复方三生注射液的研究   总被引:1,自引:0,他引:1  
复方三生注射液是由生附片等六味中药组成的静注用灭菌水溶液。本文综合报道了该制剂的制备方法,质量分析,抗肺癌作用的药理及临床等研究的主要内容。结果表明,本品是治疗中晚期肺癌有效的中药复方注射剂。  相似文献   
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