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目的:采用核磁共振氢谱(~1H-NMR)植物代谢组学技术比较青海产区枸杞子与其他产区(宁夏、甘肃、新疆、内蒙古)枸杞子的化学成分差异。方法:收集5个产区共97份枸杞子样本,其中青海61个样本,采用50%甲醇提取,检测~1H-NMR图谱,结合多元统计分析,对比青海产区枸杞子与其他产区枸杞子的化学差异性,并对各产区样本的枸杞多糖进行含量测定(以无水葡萄糖计),检测波长490 nm。结果:枸杞子的~1H-NMR图谱共检测到32个化学成分,多元统计分析表明青海产区枸杞子与其他产区样本相比,无明显分离趋势;青海产区枸杞子与宁夏产区相比,以及青海省6个不同地区的枸杞子相比,重叠样品较多,均不能显著分开。相似度结果表明,大多数样品的相似度0.85;化合物的单变量分析结果显示,除了蔗糖、葡萄糖、脯氨酸等个别代谢物在各产区样本中存在显著差异外,其余代谢物在各产区样品中的含量分布基本一致。青海与其他产区样本中枸杞多糖含量无显著性差异,且枸杞多糖含量与~1H-NMR指认的小分子化合物的相关系数处于-0.2~0.4。结论:采用~1HNMR植物代谢组学技术从整体化学组成上分析了青海产区枸杞子的化学特征,并结合枸杞多糖含量测定,显示青海产区枸杞子与其他产区枸杞子的化学差异较小。建立的基于~1H-NMR的枸杞子质量评价方法可为其质控水平提升及种植产区选择提供科学依据。 相似文献
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The impact of the COVID-19 pandemic on radiotherapy services in England,UK: a population-based study
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Michel Kahaleh Everson LA Artifon Manuel Perez-Miranda Monica Gaidhane Carlos Rondon Takao Itoi Marc Giovannini 《World journal of gastroenterology : WJG》2015,21(3):726-741
Endoscopic retrograde cholangiopancreatography(ERCP) is the preferred procedure for biliary and pancreatic drainage.While ERCP is successful in about 95% of cases,a small subset of cases are unsuccessful due to altered anatomy,peri-ampullary pathology,or malignant obstruction.Endoscopic ultrasound-guided drainage is a promising technique for biliary,pancreatic and recently gallbladder decompression,which provides multiple advantages over percutaneous or surgical biliary drainage.Multiple retrospective and some prospective studies have shown endoscopic ultrasoundguided drainage to be safe and effective.Based on the currently reported literature,regardless of the approach,the cumulative success rate is 84%-93% with an overall complication rate of 16%-35%.endoscopic ultrasoundguided drainage seems a viable therapeutic modality for failed conventional drainage when performed by highly skilled advanced endoscopists at tertiary centers with expertise in both echo-endoscopy and therapeutic endoscopy 相似文献
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Oral ulcerations associated with HIV infection include recurrent aphthous ulcers (RAU). Whereas RAU prevalence is not increased, lesion severity is: among a group of HIV+ patients, 66% had the more severe herpetiform or major RAU. This increased severity suggests that HIV disease-related changes in the immune system may exacerbate RAU. In the peripheral blood of healthy subjects with RAU, CD4:CD8 cell ratios may be reversed and the proportion of T cell receptor-γδ+ cells increased. HIV disease-related immune system changes are characterized by reversed CD4:CD8, lowered CD4 cell counts and an inverse correlation between CD4 cell counts and per cent activated γδ lymphocytes. Adhesion molecules and cytokines involved in lymphocyte homing may be important in RAU pathogenesis: ICAM-I and ELAM are strongly expressed, and TNFα production is increased in peripheral blood lymphocytes of healthy patients with RAU. In patients with active HIV disease/AIDS, serum TNFα levels are increased. Thalidomide, which inhibits TNFα production, is effective treatment for RAU. Some RAU patients have vitamin B12 or folate deficiencies, levels of which are commonly low in HIV+/AIDS patients. However, in a case control study of HIV+ patients, vitamin B12- or folate-deficiencies were not found to be significant risk factors for RAU. 相似文献
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This prospective, randomized, crossover study of 16 patients with obstructive sleep apnoea (OSA) [12 males, four females; median body mass index (BMI) 29.2 kg/m(2) (range 23.8-51.1); median age 44.8 years (range 24.0-68.4)] analysed the efficacy of the Twin Block (TB) in relation to the Herbst appliance as a mandibular advancement splint (MAS). Each subject was fitted with a TB and Herbst MAS in a random order with a washout period of 2 weeks between appliances. Once each patient was subjectively happy with the performance of each appliance, questionnaires and a visual analogue scale (VAS) were used to determine differences in snoring, daytime sleepiness, quality of life, side-effects of the appliances and patient preference. All patients underwent overnight domiciliary sleep recordings prior to and after fitting each appliance in order to objectively assess sleep quality in terms of the apnoea-hypopnoea index (AHI), snoring frequency and arterial oxygen saturation.The results suggested that there was no difference in the treatment performance of the TB and Herbst MAS for AHI (P = 0.71), snoring frequency (P = 0.49), arterial blood oxygen saturation (P = 0.97), quality of life and side-effects. The Herbst MAS proved to be the more effective appliance for reducing daytime sleepiness (P = 0.04) and was the more popular appliance among the patients. Side-effects with both appliances were minor and improved in the longer term. The TB MAS represents a viable alternative to the Herbst MAS in the treatment of patients with OSA. 相似文献
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JM Palefsky M-E Penaranda LT Pierik LA Lagenaur LA MacPhail D Greenspan JS Greenspan 《Oral diseases》1997,3(Z1):S171-S176
Hairy leukoplakia (HL) is a lesion found on the side of the tongue of immunocompromised individuals, including those with human immunodeficiency virus (HIV) infection. The lesion has unique histopathologic features and is characterised by high-level Epstein-Barr virus (EBV) replication, multiple EBV strains, and extensive inter-and intra-strain recombination. Expression of EBV genes spanning the entire viral life cycle from latency-associated genes to late, replicative genes has been detected in the lesion. HL thus provides a unique opportunity to study EBV expression in oral epithelium, and to study expression of novel EBV genes. We therefore constructed a cDNA library from an HL biopsy and detected expression of two genes not previously described in vivo: BMRF-2 and BDLF-3. Sequence analysis of the cDNAs revealed few amino acid changes from the B95-8 sequence. Expression of both genes was localized to the lower prickle cell layer of the tongue epithelium. BMRF-2 protein expression was primarily detected in the cell nuclei of the upper prickle cell layer. BDLF-3 protein expression was observed in the perinuclear space and Golgi compartment. The function of these proteins is currently under investigation. 相似文献