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31.
Chronic obstructive pulmonary disease (COPD) is characterised by a local pulmonary inflammatory response to respiratory pollutants and by systemic inflammation. Tumour necrosis factor (TNF)-alpha has been implicated in systemic effects of COPD and operates by binding the p55 (R1) and p75 (R2) TNF-alpha receptors. To investigate the contribution of each TNF-alpha receptor in the pathogenesis of COPD, the present study examined the effects of chronic air or cigarette smoke (CS) exposure in TNF-alpha R1 knockout (KO) mice, TNF-alpha R2 KO mice and wild type (WT) mice. CS was found to significantly increase the protein levels of soluble TNF-alpha R1 (by four-fold) and TNF-alpha R2 (by 10-fold) in the bronchoalveolar lavage of WT mice. After 3 months, CS induced a prominent pulmonary inflammatory cell influx in WT and TNF-alpha R1 KO mice. In TNF-alpha R2 KO mice, CS-induced pulmonary inflammation was clearly attenuated. After 6 months, no emphysema was observed in CS-exposed TNF-alpha R2 KO mice in contrast to WT and TNF-alpha R1 KO mice. CS-exposed WT and TNF-alpha R1 KO mice failed to gain weight, whereas the body mass of TNF-alpha R2 KO mice was not affected. These current findings suggest that both tumour necrosis factor-alpha receptors contribute to the pathogenesis of chronic obstructive pulmonary disease, but tumour necrosis factor-alpha receptor-2 is the most active receptor in the development of inflammation, emphysema and systemic weight loss in this murine model of chronic obstructive pulmonary disease.  相似文献   
32.
OBJECTIVES: To evaluate a novel method for localization of subdural electrodes in presurgical assessment of patients with drug-resistant focal epilepsy. METHODS: We studied eight consecutive patients with posterior epilepsy in whom subdural electrodes were implanted for presurgical evaluation. Electrodes were detected on post-implantation brain CT scans through a semiautomated procedure based on a MATLAB routine. Then, post-implantation CT scans were fused with pre-implantation MRI to localize the electrodes in relation to the underlying cortical structures. The reliability of this procedure was tested by comparing 3D-rendered MR images of the electrodes with electrode position as determined by intraoperative digital photography. RESULTS: In each patient, all electrodes could be correctly localized and visualized in a stereotactic space, thus allowing optimal surgery planning. The agreement between the procedure-generated images and the digital photographs was good according to two independent raters. The mean mismatch between the 3D images and the photographs was 2 mm. CONCLUSIONS: While our findings need confirmation on larger samples including patients with anterior epilepsy, this procedure allowed to localize subdural electrodes and to establish the spatial relationship of each electrode to the underlying brain structure, either normal or damaged, on brain convessity, basal and medial cortex. SIGNIFICANCE: Being simple, rapid, unexpensive, and reliable, this procedure holds promise to be useful to optimize epilepsy surgery planning.  相似文献   
33.
BACKGROUND: Ankle brachial index(ABI)is widely involved in researches and clinical application of peripheral vascular injury of patients with diabetes (DM);however ,the application in cerebral infarction(CI)is rare.OBJECTIVE: To investigate the possible risk factor of cerebral infarction plus peripheral arterial disease(PAD),compare metabolic characteristics of patients who having CI plus PAD or only having CI,and understand the significance of ABI on screening and diagnosing CI plus PAD of lower limb.DESIGN: Contrast observation based on CI patients.SETTING: Deparment of Neurology,Nanxishan Hospital of Guangxi Zhang Autonomous Region.PARTICIPANTS:A total of 124 CI patients were selected from Department of Neurology.Nanxishan Hospital of Guangxi Zhuang Autonomous Region from July 2005 to April 2006,including 72 males and 52 females aged from 45 to 88 years.All patients met the diagnostic criteria of cerebrovascular disease established by National Academic Conference of Cerebrovascular Diseases in 1995 and determined as cerebral infarction with MRI or CT examination.All patients provided informed consent.There were 46 cases(37.2%)with CI plus PAD and 78 cases(62.8%)only with CI.METHODS: Blood pressure of bilateral ankles and upper extremities was measured at plain clinostatism with DINAMAP blood pressure monitor(GE Company).The ratio between average systolic pressure of lateral ankle and average systolic pressure of both upper extremities was regarded as ABI.The normal ABI was equal to or more than 0.9.If ABI<0.9 occurred at one side,patients were diagnosed as PAD.On the second morning after hospitalization,blood was collected to measure fasting blood glucose(FBG),2-hour postprandial blood glucose(PBG2h),glycosylated hemoglobin(HbAlc),triglycerides(TG),total cholesterol(TC),high-density lipoprotein cholesterol(HDL-C)and low-density lipoprotein cholesterol(LDL-C).Among them,blood glucose.lipid and other biochemical markers were measured with enzyme chemistry assay and HbA1c was measured with HbA1c meter based on high liquid phase.Measurement data and enumeration data were compared with t test and Chi-square test.and multiple factors were deat with Logistic regression analysis and multivariate linear regression analysis.MAIN OUTCOME MEASURES: Results of correlation between ABI and metabolic markers with multivariate linear regression analysis;risk factors of CI plus PAD with Logistic regression analysis;comparisons of metabolic markers between PAD and non-PAD patients.RESULTS:All 124 patients with acute CI were involved in the final analysis.①Comparisons of metabolic markers:Levels of serum LDL-C and uric acid(UA)were higher of PAD patients than those of non-PAD patients(t=2.051 9,3.339 1,P<0.05);however,there were no significant differences among other metabolic markers(P>0.05).②Results of multivariate linear regression analysis:PBG2h,LDL.C and UA were obvious correlation with ABI of posterior tibial artery of lower limb and dorsal pedis artery rpartial regression coefficient:-0.231 to-1.010,P<0.05).③Risk factors of CI plus PAD with Logistic regression analysis:Age.Smoking history,sum of CI focus(≥3)and LDL-C were independent risk factor of CI plus PAD(OR=1.524-5.422,P<0.05-0.01 ).CONCLUSION:①Levels of serum LDL-C and UA of patients with CI plus PAD are high.②ABI of lower limbs is correlation with PBG2h,LDL-C and UA.In addition,measuring ABI is beneficial for early diagnosing PAD of lower limbs of patients who have poorly controlled blood glucose,abnormal lipid and poor renal function.③Age,LDL-C and sum of CI focus(≥3)are independent risk factors of CI plus PAD.It is of significance for screening non-PAD patients to evaluate risk degrees and prognosis and select therapeutic methods based on ABI measurement.  相似文献   
34.
Abstract Guillain-Barré syndrome (GBS) is a disease of the peripheral nervous system, which is caused by aberrant immune responses directed against some components of peripheral nerves. GBS is rarely accompanied by cardiovascular involvement. We describe a case of acute neuropathy complicated by sudden heart failure and left ventricular dysfunction which had a presumably neurogenic origin. Pathogenesis of acute heart failure is probably due to transitorial stunned myocardium and neurogenic cardiac injury. We show a rare case of transitorial and acute cardiac dysfunction by echocardiography and laboratory markers of heart failure.  相似文献   
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37.
Vitiligo and psoriasis are both common skin disorders. However, psoriasis strictly confined to pre-existing vitiligo areas is rare and suggests a causal relationship. We report here on two patients with a strict anatomical colocalization of vitiligo and psoriasis. The histopathological examinations showed typical changes for both diseases together with a dense infiltrate of CD4+ and CD8+ T cells. By immunohistochemistry, intracytoplasmatic granzyme B and tumour necrosis factor alpha (TNF-alpha) were detected within the T-cell population, suggesting the functional activity of these cells and the creation of a local T helper 1 (Th1)-cytokine milieu. Additionally, in one patient we could identify anti-melanocytic T cells by tetramer staining and enzyme-linked immunospot (ELISPOT) analysis. These skin-infiltrating lymphocytes might trigger, by the local production of Th-1 cytokines such as TNF-alpha and interferon-gamma (IFN-gamma), the eruption of psoriatic plaques in patients with a genetic predisposition for psoriasis.  相似文献   
38.
AIM: Cardiovascular risk factors can be present in children and young adults. We previously found abnormal microvascular function in children who had glucose intolerance and insulin resistance. The aim of the present study was to investigate whether they also have abnormalities in left ventricular mass (LVM) and arterial stiffness. METHODS: We measured heart dimensions and LVM using echocardiography, and arterial stiffness using pulse wave analysis in 23 children with good glucose handling (postfeeding glucose: 3.9 to 5 mmol/L) and 21 with poor glucose handling (7.7 to 11.4 mmol/L). RESULTS: The time to pulse reflection was slightly shorter in the poorer glucose handlers (mean+/-SD: 143+/-10 vs 153+/-20 ms, P=0.04), suggestive of increased arterial stiffness. Also in this group, there were significant relationships between intraventricular septal thickness, blood pressure and body mass index, but not in the normal glucose handlers. CONCLUSIONS: We have found that normal children who are in the lowest quintile of glucose tolerance in comparison with their peers are exhibiting the first signs of arterial stiffening. In addition, we have seen the beginnings of a relationship between blood pressure, body mass index and left ventricular enlargement in this group. While these changes may not yet be clinically significant, their emergence might be further evidence of early predisposition to cardiovascular disease.  相似文献   
39.
目的:描述胚胎种植前遗传诊断在1例携带Ⅰ型白细胞黏附缺陷病(LAD-1)携带者并完成健康妊娠夫妇中的应用。设计:病例报道。机构:大学医院生殖中心。患者:1例男女双方都是LAD-1携带者的夫妇,女方CD18基因的外显子4携带有G400A置换,男方的外显子5携带有C562T置换。干预:标准体外受精(IVF)后第3天行卵裂期活检和分裂球遗传分析以检测2处突变以及21号染色体标记物。主要观察指标:1个未罹患LAD-1婴儿的出生。结果:得到15个卵母细胞,其中10个受精。8个胚胎适宜胚胎活组织检查。  相似文献   
40.
Setting goals to maintain hope.   总被引:3,自引:0,他引:3  
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