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101.
目的建立痛可舒酊中冰片的含量测定方法。方法气相色谱法。PEG-20M为固定相,涂布浓度为10%,柱长3.2m,检测器为FID,载气为氮气,色谱柱温:150℃。结果在2.50~20.0mg/ml的范围内线性关系良好,平均回收率为99.06%,RSD为2.70%。结论该法简便高效,结果准确可靠,可用于痛可舒酊的质量控制。  相似文献   
102.
目的 分析刺五加功能基因密码子的使用方式及其影响因素。方法 以刺五加的17条功能基因为材料,利用CodonW和SPSS软件进行多元统计分析和对应性分析。结果 刺五加功能基因密码子3个位置的GC量依次为51.03%、41.23%和40.04%,三者均与整个编码区的GC量显著相关(P<0.05),GC12与GC3的相关系数为0.262,未达到显著水平。同义密码子的相对使用频率大于1的密码子共27个,其中22个以A或T碱基结尾。对应性分析的结果表明,第1轴显示了22.78%的差异,与GC3、密码子适应指数和密码子偏好指数均极显著相关(P<0.01),相关系数分别为0.786、0.686和0.617,与有效密码子数的相关性未达显著水平。第2轴显示了19.28%的差异,且仅与有效密码子数极显著相关(r=0.635)。确定了刺五加功能基因的17个最优密码子。结论 刺五加的功能基因偏好使用以A或T碱基结尾的密码子,其使用模式受选择和突变的共同影响。  相似文献   
103.
目的 观察甲基强的松龙联合盐酸溴己新治疗儿童毛细支气管炎的远期效果.方法 85例毛细支气管炎患儿随机分为观察组(n=43)和对照组(n=42),对照组在常规治疗的基础上给予甲基强的松龙1~2 mg/kg,7 d,观察组在对照组的基础上给予盐酸溴己新4~8 mg/d,7 d.观察两组患儿的病情变化以及2年内喘息复发情况.结果 观察组患儿的症状、体征消失时间以及住院时间均明显低于对照组(P<0.05),喘息复发率也明显低于对照组(P<0.05).观察组总有效率为100.0%,明显高于对照组的88.0%,差异有统计学意义(P<0.05).观察组的不良反应发生率为9.3%,低于对照组的14.3%,但差异无统计学意义(P>0.05).结论 甲基强的松龙联合盐酸溴己新不仅能快速改善患儿的症状和体征,减少住院时间,还能减少喘憋发作,安全可靠,但仍需要进一步大样本多中心随机对照研究证实结论.  相似文献   
104.
董超  李东宝  周进 《中国肿瘤临床》2021,48(18):946-949
胃癌是发病率高且进展较快的消化道恶性肿瘤之一。随着手术、化疗、靶向治疗等多种治疗方法的不断进步,胃癌患者的5年生存率较过去有所改善,但由于胃癌早期缺乏有效的诊断方法,多数患者在确诊时往往已发生转移,预后较差。因此,对胃癌转移机制的探寻始终是胃癌研究领域的热点之一。外泌体是一种可以传递蛋白质、核酸等多种分子、实现细胞间信息交流的胞外囊泡。外泌体运载的分子参与了胃癌的转移过程,并且可能成为诊断胃癌的新型分子标志物,为胃癌的精准治疗提供了新方向。本文就外泌体在胃癌转移中的作用及机制进行综述。  相似文献   
105.
Helicobacter pylori (H. pylori) are pathogenic bacteria that infect a half of the human population, colonize gastric mucosa and can be found in gastric juice. Reflux of gastric juice has been suggested to be associated with glue ear in children. It has been suggested that tonsil and adenoid tissues are potential reservoirs of H. pylori infection. These observations raise the question as to whether H. pylori infection might have a role in otitis media with effusion (OME) in children. The objectives of this research were to evaluate the incidence and possible role of H. pylori in the pathogenesis of OME in children and to evaluate the clarithromycin-resistant strains. Molecular assessment was done to evaluate the culture results vs. molecular study. A total of 60 children, who were prone to ventilation tube insertion, adenoidectomy and/or tonsillectomy were included in the study. The control group consisted of 40 children who underwent adenoidectomy and/or tonsillectomy without the history of OME. Samples of the middle ear fluid and mucosa, adenoid tissue, tonsillar tissue and gastric lavage were cultured and underwent polymerase chain reaction (PCR) analysis then were assembled by using QIAxcel System as capillary electrophoresis for H. pylori detection. There was significant difference between the results of cultures and PCR (P < 0.05). Middle ear fluid culture was positive for H. pylori in 40% of the patients vs. 56.7% PCR results while middle ear mucosa culture was positive in 20% vs. 26.7% PCR results. Gastric lavage culture was positive in 46.6% of the patients and PCR was positive in 63.3% of the patients. Adenoid culture and PCR were positive in 56.3% for each, while tonsil culture was positive in 70% and PCR was positive in 90%. H. pylori presence in the gastric lavage, the tonsillar and adenoid tissues by culture and PCR was significantly more frequent in the study group compared to the control group. The minimum inhibitory concentration (MIC) values of clarithromycin-resistant isolates ranged from 1.5 to 8 μg/ml. This study showed the presence of H. pylori in around 50% of the patients with OME. PCR revealed its sensitivity than culture techniques. The incidence of clarithromycin resistance was found to be high among the isolates (39.6%).  相似文献   
106.
目的建立气相色谱法测定卡培他滨原料药中二氯甲烷、乙醇、甲醇和乙酸乙酯4种有机溶剂。方法采用DB-624毛细管柱,FID检测器,以DMSO为溶剂。结果各有机溶剂的平均加样回收率为93.7%~97.6%,RSD为2.5%~3.7%。结论该方法稳定准确,可用于卡培他滨中有机溶剂残留的检测。  相似文献   
107.
AimEssential hypertension (EH) is one of the most important public health problems worldwide. However, the pathogenesis of EH is unclear and early diagnostic methods are lacking. Metabolomics demonstrates great potential for biomarker discovery and the mechanistic exploration of metabolic diseases.Data synthesisThis review included human and animal metabolomics studies related to EH in the PubMed and Web of Science databases between February 1996 and May 2020. The study designs, EH standards, and reported metabolic biomarkers were systematically examined and compared. The pathway analysis was conducted through the online software MetaboAnalyst 4.0.Twenty-two human studies and fifteen animal studies were included in this systematic review. There were many frequently reported biomarkers with consistent trends (e.g., pyruvate, lactic acid, valine, and tryptophan) in human and animal studies, and thus had potential as biomarkers of EH. In addition, several shared metabolic pathways, including alanine, aspartate, and glutamate metabolism, aminoacyl-tRNA biosynthesis, and arginine biosynthesis, were identified in human and animal metabolomics studies. These biomarkers and pathways, closely related to insulin resistance, the inflammatory state, and impaired nitric oxide production, were demonstrated to contribute to EH development.ConclusionsThis study summarized valuable metabolic biomarkers and pathways that could offer opportunities for the early diagnosis or prediction of EH and the discovery of the metabolic mechanisms of EH.  相似文献   
108.
The microvascular network formed by the capillaries supplies the tissues and permits their function. It provides a considerable surface area for exchanges between blood and tissues. All pathological conditions cause changes in the microcirculation. These changes can be used as imaging biomarkers for the diagnosis of lesions and optimisation of treatment. Among the many imaging techniques developed to study the microcirculation, the analysis of the tissue kinetics of intravenously injected contrast agents is the most widely used, either as positive enhancement for CT, T1-weighted MRI and ultrasound – dynamic contrast-enhanced-imaging (DCE-imaging) – or negative enhancement in T2*-weighted brain MRI – dynamic susceptibility contrast-MRI (DSC-MRI) –. Acquisition involves an injection of contrast agent during the acquisition of a dynamic series of images on a zone of interest. These kinetics may be analyzed visually, to define qualitative criteria, or with software using mathematical modelling, to extract quantitative physiological parameters. The results depend on the acquisition conditions (type of imaging device, imaging mode, frequency and total duration of acquisition), the type of contrast agent, the data pre-processing (motion correction, conversion of the signal into concentration) and the data analysis method. Because of these multiple choices it is necessary to understand the physiological processes involved and understand the advantages and limits of each strategy.  相似文献   
109.
Interstitial lung disease (ILD) in children (chILD) is a heterogeneous group of rare respiratory disorders that are mostly chronic and associated with high morbidity and mortality. The pathogenesis of the various chILD is complex and the diseases share common features of inflammatory and fibrotic changes of the lung parenchyma that impair gas exchanges. The etiologies of chILD are numerous. In this review, we chose to classify them as ILD related to exposure/environment insults, ILD related to systemic and immunological diseases, ILD related to primary lung parenchyma dysfunctions and ILD specific to infancy. A growing part of the etiologic spectrum of chILD is being attributed to molecular defects. Currently, the main genetic mutations associated with chILD are identified in the surfactant genes SFTPA1, SFTPA2, SFTPB, SFTPC, ABCA3 and NKX2-1. Other genetic contributors include mutations in MARS, CSF2RA and CSF2RB in pulmonary alveolar proteinosis, and mutations in TMEM173 and COPA in specific auto-inflammatory forms of chILD. However, only few genotype-phenotype correlations could be identified so far. Herein, information is provided about the clinical presentation and the diagnosis approach of chILD. Despite improvements in patient management, the therapeutic strategies are still relying mostly on corticosteroids although specific therapies are emerging. Larger longitudinal cohorts of patients are being gathered through ongoing international collaborations to improve disease knowledge and targeted therapies. Thus, it is expected that children with ILD will be able to reach the adulthood transition in a better condition.  相似文献   
110.
BackgroundMultidisciplinary management of patients with locally advanced gastric cancer (LAGC) remains unstandardized worldwide. We performed a systemic review to summarize the advancements, regional differences, and current recommended multidisciplinary treatment strategies for LAGC.MethodsEligible studies were identified through a comprehensive search of PubMed, Web of Science, Cochrane Library databases and Embase. Phase 3 randomized controlled trials which investigated survival of patients with LAGC who underwent gastrectomy with pre-/perioperative, postoperative chemotherapy, or chemoradiotherapy were included.ResultsIn total, we identified 11 studies of pre-/perioperative chemotherapy, 38 of postoperative chemotherapy, and 14 of chemoradiotherapy. In Europe and the USA, the current standard of care is perioperative chemotherapy for patients with LAGC using the regimen of 5-FU, folinic acid, oxaliplatin and docetaxel (FLOT). In Eastern Asia, upfront gastrectomy and postoperative chemotherapy is commonly used. The S-1 monotherapy or a regimen of capecitabine and oxaliplatin (CapOx) are used for patients with stage II disease, and the CapOx regimen or the S-1 plus docetaxel regimen are recommended for those with stage III Gastric cancer (GC). The addition of postoperative radiotherapy to peri- or postoperative chemotherapy is currently not recommended. Additionally, clinical trials testing targeted therapy and immunotherapy are increasingly performed worldwide.ConclusionsRecent clinical trials showed a survival benefit of peri-over postoperative chemotherapy and chemoradiotherapy. As such, this strategy may have a potential as a global standard for patients with LAGC. Outcome of the ongoing clinical trials is expected to establish the global standard of multidisciplinary treatment strategy in patients with LAGC.  相似文献   
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