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81.
AIM: To investigate whether narrow band imaging (NBI) is a useful tool for the in vivo detection of angiogenesis in inflammatory bowel disease (IBD) patients. METHODS: Conventional and NBI colonoscopy was performed in 14 patients with colonic inflammation (8 ulcerative colitis and 6 Crohn’s disease). Biopsy samples were taken and CD31 expression was assayed immuno- histochemically; microvascular density was assessed by vessel count. RESULTS: In areas that were endoscopically normal but positive on NBI, ther...  相似文献   
82.
目的 研究HIV-1膜蛋白(Env)特定中和表位的改造对功能性假病毒形成及中和活性的影响.方法 采用环形诱变及Dpn I筛选的方法对Env进行定点突变,将2G12和2F5两个中和表位整合入不含该表位的BC亚型的Env上,比较改造对假病毒的形成情况及对2G12和2F5单抗的中和活性的影响.结果 对5株假病毒(BC02、BE03、BC04、BC05和BC12)的Env特定中和表位进行改造,其中BC04和BCl2的2G12表位改造后,不能形成假病毒,BC02、BC03和BC05增加2G12和2F5两个表位后,仍能够形成假病毒,且假病毒滴度较改造前无明显变化,改造后的BC03假病毒较改造前对单抗2G12和2175的中和活性均有所提高,而改造后的BE02和BC05假病毒较改造前对单抗2F5的中和活性增强,而对单抗2G12的中和活性无变化.结论 2G12中和表位部分位点的改造影响假病毒的形成,中和表位的增加能够提高单抗2G12的中和活性,为免疫原的优化提供了新思路.  相似文献   
83.
Multiple sclerosis (MS) is a demyelinating disease of the central nervous system (CNS) mediated by blood-derived immune cells invading the CNS. This invasion could be determined by chemokines, and their role within the MS-affected brain is still poorly defined. We investigated the expression by RT-PCR and protein release by ELISA of the interferon-gamma (IFN-gamma)-inducible chemokines in human brain microvascular endothelial cells (HBMECs) and astrocytes. The monokine induced by IFN-gamma (Mig) behaves as a homing chemokine constitutively expressed in HBMECs and astrocytes, whereas the IFN-gamma-inducible 10-kDa protein (IP-10) and IFN-inducible T cell alpha-chemoattractant (I-TAC) are induced only after inflammatory stimuli. The biologic activity of IFN-gamma-inducible chemokines from an endothelial source was analyzed, and the transendothelial migration of activated lymphocytes was partly antagonized by specific antibodies, especially anti-Mig antibody. Our data highlight the capability of cells of the CNS to activate the chemoattractant machinery in a proinflammatory environment and in MS.  相似文献   
84.
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85.
Objective: To study the relation between CD226 rs763361 gene polymorphism and CD226 serum level and to evaluate their role in susceptibility and disease activity of RA in a cohort of Egyptian individuals.

Methods: The serum level of CD226 was measured using a suitable ELISA kit and the CD226 rs763361 gene polymorphism was typed by PCR-RFLP for 112 RA patients and 100 healthy controls.

Results: Significant association with RA was found with CD226 T allele (OR (95%CI) = 1.6 (1.04–2.4), P = 0.032), and higher CD226 serum level (P = 0.001). Higher CD226 levels were associated with higher ESR values (P = 0.035), positive CRP (0.048), increased number of tender joints (P = 0.045), and higher DAS score (P = 0.035). Serum CD226 is an independent risk factor for the prediction of RA (P = 0.001). No correlations were found between the serum level of CD226 and different CD226 genotypes and also between them and RA activity grades.

Conclusion: The CD226 T allele may be susceptibility risk factors for the development of RA and the higher serum level of CD226 may be involved in the pathogenesis of RA in Egyptian patients. The serum level of CD226 and not CD226 genotypes could be considered as an independent risk factor for the prediction of RA within healthy individuals and also for RA disease activity.  相似文献   

86.
We have recently shown using dansyl-L-lysine exclusion studies that the release of human chorionic gonadotrophin (HCG) in conjunction with L- lactate dehydrogenase (LDH) from first trimester villi during organ culture is symptomatic of syncytiotrophoblast degeneration. The purpose of this study was to examine chorionic villi at the ultrastructural level in order to determine events occurring during organ culture. The tissue was sampled after 0, 24, 48 and 120 h in culture and processed for electron microscopy. In addition to confirming the previously recorded syncytial degeneration, the electron micrographs showed clearly the generation of a new syncytiotrophoblast layer. The new layer, derived from differentiating cytotrophoblast cells, was largely formed by 48 h and was maintained for at least 120 h in culture. This study demonstrates a model which provides an opportunity to study the differentiation of cytotrophoblast cells whilst they retain their anatomical relationships within the villous structure.   相似文献   
87.
88.
目的 探讨勃脉力A注射液对体外循环心脏手术患者肝功能的影响.方法 选择术前肝功能正常、无肝炎病史的行体外循环心脏手术患者60名,随机分为勃脉力A组(P组)和林格液组(R组).所有患者均在术前、术后2h、1d、3d、7d分别采肘正中静脉血和挠动脉血:静脉血分离血清后应用自动血生化分析仪检测血清中天冬氨酸转氨酶和丙氨酸氨基转移酶,以了解患者的肝脏功能改变;抽取动脉血查乳酸浓度.术中及术后密切观察患者血压、心率、中心静脉压、尿量等,观察并记录患者拔管及停留ICU时间.结果 与R组相比较,在术后各时间点P组ALT、AST及乳酸浓度均显著降低(P﹤0.05),并且拔除气管导管时间和停留ICU时间均有所缩短.结论 勃脉力A注射液能够显著降低体外循环术中乳酸浓度,并能改善患者肝功能,非常适用于体外循环手术.  相似文献   
89.
90.

Purpose

Sympathetic nervous system (SNS) hyperactivity is a salient characteristic of chronic heart failure (HF) and contributes to the progression of the disease. Iodine-123 meta-iodobenzylguanidine (123I-mIBG) imaging has been successfully used to assess cardiac SNS activity in HF patients and to predict prognosis. Importantly, SNS hyperactivity characterizes also physiological ageing, and there is conflicting evidence on cardiac 123I-mIBG uptake in healthy elderly subjects compared to adults. However, little data are available on the impact of ageing on cardiac sympathetic nerve activity assessed by 123I-mIBG scintigraphy, in patients with HF.

Methods and results

We studied 180 HF patients (age?=?66.1?±?10.5 years [yrs]), left ventricular ejection fraction (LVEF?=?30.6?±?6.3 %) undergoing cardiac 123I-mIBG imaging. Early and late heart to mediastinum (H/M) ratios and washout rate were calculated in all patients. Demographic, clinical, and echocardiographic data were also collected. Our study population consisted of 53 patients aged >75 years (age?=?77.7?±?4.0 year), 67 patients aged 62–72 years (age?=?67.9?±?3.2 years) and 60 patients aged ≤61 year (age?=?53.9?±?5.6 years). In elderly patients, both early and late H/M ratios were significantly lower compared to younger patients (p?<?0.05). By multivariate analysis, H/M ratios (both early and late) and washout rate were significantly correlated with LVEF and age.

Conclusions

Our data indicate that, in a population of HF patients, there is an independent age-related effect on cardiac SNS innervation assessed by 123I-mIBG imaging. This finding suggests that cardiac 123I-mIBG uptake in patients with HF might be affected by patient age.
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