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11.
OBJECTIVES: To determine the spectrum of N and G genotypes of respiratory syncytial virus (RSV) causing respiratory tract infection and whether particular genotypes are associated with severity of infection. PATIENTS AND METHODS: Nasopharyngeal aspirates (NPAs) were obtained from 114 infants with acute respiratory tract infection due to RSV over two seasons. Viral mRNA was extracted from NPAs or cultured virus, reverse transcribed, and the cDNA amplified by the polymerase chain reaction using primers directed to parts of the N and G gene respectively. Amplicons were separately digested with four different restriction endonucleases for each gene. The fragments were separated by agarose gel, electrophoresis, and the electrophoretic patterns used to assign the various genotypes. Disease severity was assessed as very mild (upper respiratory tract signs only), mild (coryza and signs of lower respiratory tract infection), moderate (requiring nasogastric or intravenous fluids), and severe (requiring oxygen or ventilation). RESULTS: Five of the six known N genotypes were detected, but NP4 and NP2 were found most frequently. There was no association between N genotype and disease severity. Six G (SHL) genotypes were detected. Significantly (p = 0.04) more of the infants infected with the SHL2 genotype had severe or moderate disease. CONCLUSIONS: During the seasonal peaks of RSV respiratory tract infection at least 10 different RSV genotypes cocirculated. While there is no association between N genotypes and disease severity, infection with the SHL2 G genotype appears to result in moderate to severe disease.  相似文献   
12.
目的:利用葡萄糖定量法检测根管微渗漏模型,评价侧向加压充填技术、垂直加压充填技术及固核载体充填技术对根管微渗漏的影响.方法:选取71颗直根管上前牙,根管预备后随机分为7组,A组(14颗)用热牙胶垂直加压加AH Plus充填;B组(8颗)仅用热牙胶垂直加压充填;C组(13颗)用侧方加压加AH Plus充填;D组(8颗)仅用侧方加压充填技术;E组(11颗)用Thermafil加AH Plus充填;F组(7颗)仅用Thermafil充填;G组(10颗)为阴性对照组,用粘蜡充填根管.牙根外表面、根管口及根尖孔处涂二层指甲油.于第7 d、14 d、21 d、28 d用葡萄糖氧化酶法检测从冠方向根方漏出的葡萄糖量.结果:采用重复测量方差分析,发现第7 d、14 d、21 d、28 d A、C组及C、E组微渗漏值有显著性差异(P<0.001),但A、E组无显著性差异(P>0.05).各时间点C、D组比较有显著性差异(P<0.001),但A、B组与E、F组比较无显著性差异(P>0.05).第7 d、14 d及第21 d、28 d各组内比较无显著性差异(P>0.05),但各组第14 d与第21 d比较有显著性差异(P<0.05).结论:侧方加压充填技术封闭根管的能力优于垂直加压充填技术及固核载体充填技术,而后两种充填技术封闭根管的能力相当.  相似文献   
13.
Background We aimed to assess the safety, tolerability and pharmacokinetics of a novel anti-angiogenic peptide.Methods We used an open-label, multicentre, dose-escalation Phase I trial design in patients with solid tumours. ALM201 was administered subcutaneously once daily for 5 days every week in unselected patients with solid tumours.Results Twenty (8 male, 12 female) patients with various solid tumours were treated (18 evaluable for toxicity) over eight planned dose levels (10–300 mg). ALM201 was well-tolerated at all dose levels without CTCAE grade 4 toxicities. Adverse events were predominantly grades 1–2, most commonly, localised injection-site reactions (44.4%), vomiting (11%), fatigue (16.7%), arthralgia (5.6%) and headache (11%). Thrombosis occurred in two patients at the 100 mg and 10 mg dose levels. The MTD was not reached, and a recommended Phase II dose (RP2D) based on feasibility was declared. Plasma exposure increased with dose (less than dose-proportional at the two highest dose levels). No peptide accumulation was evident. The median treatment duration was 11.1 (range 3–18) weeks. Four of 18 evaluable patients (22%) had stable disease.Conclusions Doses up to 300 mg of ALM201 subcutaneously are feasible and well-tolerated. Further investigation of this agent in selected tumour types/settings would benefit from patient-selection biomarkers.Subject terms: Drug development, Drug safety  相似文献   
14.
视神经周围炎(OPN)是指涉及视神经鞘膜的一系列病理性炎症.OPN的经典三联征包括单侧视神经病变伴随疼痛和/或视盘水肿,此病症与其它视神经病变相似,导致诊断延迟和治疗欠佳.2016年1月,我们对发表于Medline和Ovid数据库的关键词为“视神经周围炎”的各种语言的文献进行了检索,共查找到60篇文献,发表于1956-2015年.两位作者(Tai ELM和Tevaraj JMP)分别对论文摘要进行了独立筛选,并筛选出相关文章.本次综述,我们强调OPN的特点,特别是OPN和视神经炎之间的临床差异.虽然大多数OPN的病例是特发性的,但仍需进行调查以排除特异性感染和继发性OPN的炎症原因.MRI是非常重要的检查方法,由于OPN视神经周围炎症的影像学诊断.糖皮质激素治疗可使症状与体征迅速好转,长期口服糖皮质激素并慢速递减可以降低复发的风险.  相似文献   
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16.

Background

Adequate vitamin D concentrations during pregnancy are necessary to neonatal calcium homeostasis, bone maturation and mineralization. The aim of study is to evaluate serum vitamin D concentrations in mothers and their newborns and effect of vitamin D deficiency on pregnancy outcomes.

Methods

552 pregnant women were recruited from Tehran University educating hospitals in the winter of 2002. Maternal and cord blood samples were taken at delivery. The serum was assayed for 25-hydroxyvitamin D3, calcium, phosphorus and parathyroid hormone.

Results

The prevalence of vitamin D deficiency in maternal and cord blood samples were 66.8% and 93.3%, respectively (<35 nmol/l). There was significant correlation between maternal and cord blood serum concentrations of vitamin D. In mothers with vitamin D deficiency, cord blood vitamin D concentrations was lower than those from normal mothers (P = .001). Also, a significant direct correlation was seen between maternal vitamin D intake and weight gain during pregnancy.

Conclusion

Consideration to adequate calcium and vitamin D intake during pregnancy is essential. Furthermore, we think it is necessary to reconsider the recommendation for vitamin D supplementation for women during pregnancy.  相似文献   
17.
In this study, we aimed to determine whether a postnatal trans fat diet (TFD) could aggravate prenatal bisphenol A (BPA) exposure effects on offspring’s small intestine and adulthood obesity, due to the relatively sparse findings on how the interaction between these two variables interrupt the small intestinal cells. Twelve pregnant rats were administered with either unspiked drinking water (control; CTL) or BPA-spiked drinking water throughout pregnancy. Twelve weaned pups from each pregnancy group were then given either a normal diet (ND) or TFD from postnatal week (PNW) 3 until PNW14, divided into control offspring on normal diet (CTL-ND), BPA-exposed offspring on normal diet (BPA-ND), control offspring on trans fat diet (CTL-TFD), and BPA offspring on trans fat diet (BPA-TFD) groups. Body weight (BW), waist circumference, and food and water intake were measured weekly in offspring. At PNW14, small intestines were collected for global DNA methylation and histological analyses. Marked differences in BW were observed starting at PNW9 in BPA-TFD (389.5 ± 10.0 g; p < 0.05) relative to CTL-ND (339.0 ± 7.2 g), which persisted until PNW13 (505.0 ± 15.6 g). In contrast, water and food intake between offspring were significantly different (p < 0.01–0.05) at earlier ages only (PNW4–6 and PNW7–9, respectively). Furthermore, substantial differences in the general parameters of the intestinal structures were exclusive to ileum crypt length alone, whereby both BPA-ND (150.5 ± 5.1 μm; p < 0.001), and BPA-TFD (130.3 ± 9.9 μm; p < 0.05) were significantly longer than CTL-ND (96.8 ± 8.9 μm). Moreover, BPA-ND (2.898 ± 0.147%; p < 0.05) demonstrated global small intestinal hypermethylation when compared to CTL-ND and CTL-TFD (1.973 ± 0.232% and 1.913 ± 0.256%, respectively). Prenatal BPA exposure may significantly affect offspring’s physiological parameters and intestinal function. Additionally, our data suggest that there might be compensatory responses to postnatal TFD in the combined BPA prenatal group (BPA-TFD).  相似文献   
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Chemotherapy for cancer causes significant gut toxicity known as mucositis. The pathogenesis of mucositis is ill defined. Recent clinical research guidelines have highlighted epithelial junctional complexes as emerging targets within mucositis research. Given the robust biological evidence linking tight junctions and matrix metalloproteinases, key mediators of mucositis, tight junction proteins have received significant attention. Despite this, the link between tight junctions, matrix metalloproteinases and mucositis development is yet to be established. This critical review therefore aims to describe the role of matrix metalloproteinases in mucositis, and how matrix metalloproteinase-dependent tight junction disruption may contribute to the pathobiology of mucositis.  相似文献   
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