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李平  郝敏  苏联麟  季德  宋嬿  秦思睿  陆兔林  毛春芹 《中草药》2018,49(23):5665-5671
目的建立天麻饮片UPLC指纹图谱和同时测定天麻饮片中天麻素、对羟基苯甲醇、巴利森苷B、巴利森苷C、巴利森苷A的超高效液相色谱分析方法。方法采用Waters Acquity超高效液相系统,Waters ACQUITY UPLC BEH C18(50 mm×2.1 mm,1.7μm)色谱柱,流动相为乙腈-0.1%甲酸水,梯度洗脱,检测波长270 nm(指纹图谱)、220 nm(含量测定),体积流量为0.3 mL/min,柱温35℃。通过相似度评价、主成分分析、偏最小二乘判别分析对28批天麻饮片指纹图谱进行分析,通过对照品比对对主要共有峰进行指认和含量测定。结果建立了不同产地天麻的指纹图谱,标定了20个共有峰,并指认了其中6个共有峰:天麻素(1号峰)、对羟基苯甲醇(3号峰)、对羟基苯甲醛(7号峰)、巴利森苷B(14号峰)、巴利森苷C(15号峰)、巴利森苷A(18号峰)。28批样品相似度均在0.90以上,主成分分析将不同产地天麻分为5组,并发现对羟基苯甲醇、对羟基苯甲醛、巴利森苷A等6个差异成分。同一成分在各产地天麻饮片中的含量差异明显,不同成分的波动范围不同,各产地5种成分总量贵州(2.52%)云南(2.49%)陕西(2.33%)湖北(2.10%)浙江(1.90%)安徽(1.65%)。结论建立不同产地天麻UPLC指纹图谱结合多成分含量测定方法为完善天麻饮片的质量控制提供了参考。  相似文献   
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采用放射免疫分析法及流式细胞术检测了35例银屑病和30例健康人血清TNFα、HA、LN含量及外周血单一核细胞CD44阳性细胞数。结果显示:银屑病患者血清TNF、HALNI浓度均明显高于对照组,差异显著,CD44一率亦显著增高,与对照组比较差异十分显著,银屑病患者CD4表达 上调与HA浓度增高呈正相关,HA与TNF亦呈正相关。提示CD44作为透明质本以体与TNF、LN共同参与了银屑病发的病理过程。  相似文献   
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Purpose

In hospital-based studies, patients intubated by physicians while in an inclined position compared to supine position had a higher rate of first pass success and lower rate of peri-intubation complications. We evaluated the impact of patient positioning on prehospital endotracheal intubation in an EMS system with rapid sequence induction capability. We hypothesized that patients in the inclined position would have a higher first-pass success rate.

Methods

Prehospital endotracheal intubation cases performed by paramedics between 2012 and 2017 were prospectively collected in airway registries maintained by a metropolitan EMS system. We included all adult (age?≥?18?years) non-traumatic, non-arrest patients who received any attempt at intubation. Patients were categorized according to initial positioning: supine or inclined. The primary outcome measure was first pass success with secondary outcomes of laryngoscopic view and challenges to intubation.

Results

Of the 13,353 patients with endotracheal intubation attempted by paramedics during the study period, 4879 were included for analysis. Of these, 1924 (39.4%) were intubated in the inclined position. First pass success was 86.3% among the inclined group versus 82.5% for the supine group (difference 3.8%, 95% CI: 1.5%–6.1%). First attempt laryngeal grade I view was 62.9% in the inclined group versus 57.1% for the supine group (difference 5.8%, 2.0–9.6). Challenges to intubation were more frequent in the supine group (42.3% versus 38.8%, difference 3.5%, 0.6–6.3).

Conclusion

Inclined positioning was associated with a better grade view and higher rate of first pass success. The technique should be considered as a viable approach for prehospital airway management.  相似文献   
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Poor health outcomes from insufficient physical activity (PA) are a persistent public health issue. Public transit is often promoted for positive influence on PA. Although there is cross-sectional evidence that transit users have higher PA levels, this may be coincidental or shifted from activities such as recreational walking. We use a quasi-experimental design to test if light rail transit (LRT) generated new PA in a neighborhood of Salt Lake City, Utah, USA. Participants (n=536) wore Global Positioning System (GPS) receivers and accelerometers before (2012) and after (2013) LRT construction. We test within-person differences in individuals’ PA time based on changes in transit usage pre- versus post-intervention. We map transit-related PA to detect spatial clustering of PA around the new transit stops. We analyze within-person differences in PA time based on daily transit use and estimate the effect of daily transit use on PA time controlling for socio-demographic variables. Results suggest that transit use directly generates new PA that is not shifted from other PA. This supports the public health benefits from new high quality public transit such as LRT.  相似文献   
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Background and aims Despite improved techniques, the determination of tumor origin in poorly differentiated adenocarcinomas still remains a challenge for the pathologist. Here we report the use of protein profiling combined with principal component analysis to improve diagnostic decision-making in tumor samples, in which standard pathologic investigations cannot present reliable results. Materials and methods A poorly differentiated adenocarcinoma of unknown origin located in the pelvis, infiltrating the sigmoid colon as well as the ovary, served as a model to evaluate our proteomic approach. Firstly, we characterized the protein expression profiles from eight advanced colon and seven ovarian adenocarcinomas using two-dimensional gel electrophoresis (2-DE). Qualitative and quantitative patterns were recorded and compared to the tumor of unknown origin. Based on these protein profiles, match sets from the different tumors were created. Finally, a multivariate principal component analysis was applied to the entire 2-DE data to disclose differences in protein patterns between the different tumors. Results Over 89% of the unknown tumor sample spots could be matched with the colon standard gel, whereas only 63% of the spots could be matched with the ovarian standard. In addition, principal component analysis impressively displayed the clustering of the unknown case within the colon cancer samples, whereas this case did not cluster at all within the group of ovarian adenocarcinomas. Conclusion These results show that 2-DE protein expression profiling combined with principal component analysis is a sensitive method for diagnosing undifferentiated adenocarcinomas of unknown origin. The described approach can contribute greatly to diagnostic decision-making and, with further technical improvements and a higher throughput, become a powerful tool in the armentarium of the pathologist. UJ Roblick and FG Bader contributed equally to this work and should be recognized as first authors.  相似文献   
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