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101.
Background. Nephropathy associated with contrast medium exposure is a well-known complication of IVP. However, it is uncertain whether iso-osmolar non-iodinated contrast medium (iodixanol) is less nephrotoxic than low-osmolar contrast medium (iohexol). Materials and Methods. In this single-center, double-blind, prospective study, 50 patients undergoing IVP were randomized into two groups receiving different contrast medium: iodixanol and iohexol. Patients in high risk for contrast nephropathy were included, 28 with renal insufficiency and 19 with diabetes mellitus. We compared the nephrotoxic effect (contrast nephropathy), complement and cytokines profile between the iodixanol and iohexol groups. The mean volume of contrast medium in each IVP procedure was 0.8 mL/kg. Results. The incidence of contrast nephropathy was 4 percent among all patients (one iodixanol and one iohexol). We found no significant differences in contrast nephropathy and allergic reactions between the two groups. There was no significant difference in cytokine profiles in both groups (p > 0.05).The incidence of allergic reaction was 16 percent among all patients. Twelve percent (3/25) had late reaction after iohexol exposure compared to four percent (2/25) with iodixanol (p = 1.0). One patient had severe skin rash due to late adverse reaction after iodixanol. No mortality was found. Conclusions. New iodixanol and iohexol contrast medium for routine IVP examination are safe and have low nephrotoxicity profile, especially in elderly or high-risk patients. Iodixanol contrast medium has an increased risk to induce severe late adverse reaction compared to iohexol. Allergic reaction may be the main adverse effect after contrast medium infusion.  相似文献   
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To investigate the role of plasma calcitonin gene-related peptide (CGRP) in paediatric migraine, we prospectively collected 134 blood samples during or between attacks from 66 migraine, 33 non-migraine headache (non-migraine) and 22 non-headache patients, aged 4–18 years. Plasma CGRP concentrations were measured by enzyme-linked immunosorbent assay and disability by Pediatric MIgraine Disability ASsessment (PedMIDAS) questionnaire. Migraineurs had higher plasma CGRP levels than non-migraine patients ( P  = 0.007). The attack level was higher than the non-attack level in migraine ( P  = 0.036), but not in non-migraine, patients. This was also revealed in paired comparison ( n  = 9, P  = 0.015 vs. n  = 4, P  = 0.47). Using a threshold of 55.1 pg/ml, the sensitivity of the attack level in predicting migraine was 0.81, and specificity 0.75. The PedMIDAS score tended to be higher in the high CGRP (> 200 pg/ml, n  = 7) group than in the low (< 200 pg/ml, n  = 33) group (26.07 vs. 19.32, P  = 0.16) using Mann–Whitney test. Plasma CGRP is useful for diagnosis in paediatric migraine.  相似文献   
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目的:研究ZX-5对缺血后视网膜功能的恢复作用,并比较其光学异构体(R,R)-ZX-5和(S,S)-ZX-5对脉络膜血流及缺血后视网膜功能恢复的影响。方法:用彩色微球技术研究兔高眼压下(40mmHg)脉络膜血流的变化。用视网膜电生理仪测量b波,评价大鼠缺血后视网膜功能的恢复情况。结果:10g/L(R,R)-ZX-5滴眼液50μL能在不同时间点提高脉络膜血流(P<0.05),而(S,S)-ZX-5在相同条件下对提高脉络膜血流没有影响。ZX-5和(R,R)-ZX-5在不同时间点对视网膜缺血后功能恢复作用明显(P<0.05),(R,R)-ZX-5的作用优于ZX-5;而(S,S)-ZX-5对缺血后视网膜功能的恢复作用不明显。结论:ZX-5和(R,R)-ZX-5对增加脉络膜血流量和促进视网膜功能的恢复有显著功效,(R,R)-ZX-5恢复视网膜功能的作用更强,有可能进一步开发成有效防治眼血流障碍相关性眼病的药物。  相似文献   
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目的:探讨在缺氧性损害下肼屈嗪对视网膜色素上皮(ARPE-19)细胞的抗氧化效果以及活性氧(ROS)在此效果中的作用。方法:用人视网膜色素上皮细胞研究肼屈嗪对氧化应激的作用,包括特丁基氢过氧化物(t-BHP)、过氧化氢(H2O2)、叠氮化钠(NaN3),以及缺氧引起的细胞坏死。用MTT检验测试细胞活性。结果:用ROS诱导的氧化应激治疗ARPE-19细胞,肼屈嗪在抵抗t-BHP、H2O2、缺氧引起的细胞坏死中表现出浓度依赖性,但对NaN3不具有浓度依赖性。这一作用中不涉及到一氧化氮(NO)。结论:肼屈嗪在ARPE-19细胞中表现出抗氧化应激诱导的破坏,这一作用可能是因为对ROS的净化剂作用。所以肼屈嗪可能用于治疗老年黄斑变性。  相似文献   
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Chromodomain, helicase, DNA binding 5 (CHD5) is a member of a subclass of the chromatin remodeling Swi/Snf proteins and has recently been proposed as a tumor suppressor in a diverse range of human cancers. We analyzed all 41 coding exons of CHD5 for somatic mutations in 123 primary ovarian cancers as well as 60 primary breast cancers using high-resolution melt analysis. We also examined methylation of the CHD5 promoter in 48 ovarian cancer samples by methylation-specific single-stranded conformation polymorphism and bisulfite sequencing. In contrast to previous studies, no mutations were identified in the breast cancers, but somatic heterozygous missense mutations were identified in 3 of 123 ovarian cancers. We identified promoter methylation in 3 of 45 samples with normal CHD5 and in 2 of 3 samples with CHD5 mutation, suggesting these tumors may have biallelic inactivation of CHD5. Hemizygous copy number loss at CHD5 occurred in 6 of 85 samples as assessed by single nucleotide polymorphism array. Tumors with CHD5 mutation or methylation were more likely to have mutation of KRAS or BRAF (P = .04). The aggregate frequency of CHD5 haploinsufficiency or inactivation is 16.2% in ovarian cancer. Thus, CHD5 may play a role as a tumor suppressor gene in ovarian cancer; however, it is likely that there is another target of the frequent copy number neutral loss of heterozygosity observed at 1p36.  相似文献   
110.
Rogers JV  Hull BE  Fink PS  Chiou HC  Bigley NJ 《Vaccine》2000,18(15):1522-1530
Plasmid DNA encoding herpes simplex virus type-1 glycoprotein D (gD-1) was complexed with asialoorosomucoid conjugated to poly-L-lysine. Following its intravenous injection into BALB/c mice, this complex was targeted to the liver. Liver cells expressing gD-1 were detected immunohistochemically through day 6 post-immunization, while gD-1 DNA was detectable through 14 days post-immunization. Decline of gD-1 expression and detectable gD-1 DNA in the liver correlated with influx of T cells, predominantly CD4(+). The ASOR-poly-L-lysine DNA carrier system promotes hepatic expression of gD-1 and may be useful in vaccination against herpes simplex virus type-1.  相似文献   
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