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91.
山沉香化学成分研究   总被引:4,自引:5,他引:4  
曾孝杰  王国才  吴霞  李国强  叶文才  李药兰 《中草药》2013,44(13):1721-1725
目的 研究山沉香Syringa pinnatifolia干燥茎的化学成分.方法 采用硅胶、ODS、Sephadex LH-20及RP-HPLC等色谱技术对山沉香干燥茎的化学成分进行分离纯化,根据理化性质及波谱数据鉴定化合物结构.结果 从山沉香干燥茎95%乙醇提取物的醋酸乙酯部位分离得到11个化合物,分别鉴定为开环异落叶松脂醇(1)、(8R,8'R,9R)-3,3',9-三甲氧基-4,4'-二羟基-9,9'-环氧木脂素(2)、(8R,8'R,9S)-3,3',9-三甲氧基-4,4'-二羟基-9,9'-环氧木脂素(3)、左旋松脂醇(4)、(8R,8'R,9'S)-3,3',9 '-三甲氧基-4,4 '-二羟基-9,9'-环氧木脂素(5)、(8R,8'R,9'R)-3,3',9'-三甲氧基-4,4'-二羟基-9,9'-环氧木脂素(6)、(9S)-9-O-methylcubebin (7)、邻苯二甲酸二丁酯(8)、菲律宾胡椒素Ⅵ (9)、蛇菰宁(10)、落叶松萘酮(11).结论 化合物2~11均为首次从该植物中分离得到.  相似文献   
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目的立足于肿瘤转移的生物学特性与痰的病理特征相似基础上,探讨痰在肿瘤转移中发挥作用的可能物质基础。方法以酶联免疫吸附法检测胃癌痰湿证型患者30例治疗前后与非痰湿证型患者32例以及健康对照组10例血清中上皮钙黏附分子(E-Cad)、基质金属蛋白酶(MMP9)的表达;痰湿证组服用消痰散结方1个月,非痰湿证组不治疗。观察治疗前后血清中E-Cad、MMP9的表达变化,并与非痰湿组血清中E-Cad、MMP9的表达进行比较对照。结果两种黏附分子表达在痰湿证型与非痰湿证型中的表达均较健康组升高(P<0.05),痰湿组较非痰湿组升高(P<0.05);治疗组治疗后E-Cad的表达明显降低(P<0.05),MMP9的表达有降低趋势,但差异不显著。结论痰在肿瘤转移中发挥作用的途径可能是通过影响黏附分子的表达,两者存在相关性。  相似文献   
93.
目的研究强力霉素对口腔溃疡的治疗作用,为临床用药提供指导。方法采用60%水醋酸酸蚀SD大鼠口腔颊黏膜建立大鼠溃疡模型。取36只造模成功大鼠随机分为3组,每组12只,分别给予高低剂量强力霉素及空白凝胶作局部治疗,分别于用药第2天、第4天、第6天每组处死4只大鼠,经过切取标本,石蜡包埋,制片,HE染色、麦氏染色和免疫组化染色后,于光镜下进行观察。结果用药后,强力霉素高低剂量组较对照组炎性渗出明显减少,充血情况明显减轻,胶原纤维降解、MMP-9的表达明显减少,溃疡愈合更快。结论强力霉素可能是通过抑制MMP-9的表达,减少胶原纤维的降解,促进口腔溃疡愈合。  相似文献   
94.
BackgroundCoronary tomography angiography (CTA) has been mainly used for chest pain evaluation in low-risk patients, and few data exist regarding patients at intermediate risk.ObjectiveTo evaluate the performance of serial measures of sensitive troponin and CTA in intermediate-risk patients.MethodsA total of 100 patients with chest pain, TIMI risk scores of 3 or 4, and negative troponin were prospectively included. All patients underwent CTA and those with coronary stenosis ≥ 50% were referred to invasive coronary angiography. Patients with coronary lesions <50% were discharged and contacted 30 days later by a telephone call to assess clinical outcomes. Outcomes were hospitalization, death, and myocardial infarction at 30 days. The comparison between methods was performed by Kappa agreement test. The performance of troponin measures and CTA for detecting significant coronary lesions and clinical outcomes was calculated. Results were considered statistically significant when p < 0.05.ResultsCoronary stenosis ≥ 50% on CTA was found in 38% of patients and significant coronary lesions on coronary angiography were found in 31 patients. Two clinical events were observed. Kappa agreement analysis showed low agreement between troponin measures and CTA in the detection of significant coronary lesions (kappa = 0.022, p = 0.78). The performance of CTA for detecting significant coronary lesions on coronary angiography or for predicting clinical events at 30 days was better than sensitive troponin measures (accuracy of 91% versus 60%).ConclusionCTA performed better than sensitive troponin measures in the detection of significant coronary disease in patients with chest pain and intermediate risk for cardiovascular events.  相似文献   
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Guillain-Barré syndrome (GBS) has occasionally occurred in people who have received coronavirus disease 2019 (COVID-19) vaccines. Dysgeusia is rare symptom of GBS. We herein report a rare case of sensory ataxic GBS with dysgeusia just after the second dose of the Pfizer-BioNTech COVID-19 vaccine. Although autoantibodies against glycolipids were not detected, immunotherapy with intravenous immunoglobulin and methylprednisolone pulse therapy effectively ameliorated the symptoms. Our report suggests that the COVID-19 vaccine may induce various clinical subtypes of GBS, including a rare variant with sensory ataxia and dysgeusia.  相似文献   
100.
BackgroundThe selective pressure imposed by chemotherapy creates a barrier to tumor eradication and an opportunity for metastasis and recurrence. As a newly discovered stemness marker of pancreatic ductal adenocarcinoma (PDAC), the impact of CD9 on tumor progression and patient''s prognosis remain controversial.MethodsA total of 179 and 211 PDAC patients who underwent surgical resection with or without neoadjuvant chemotherapy, respectively, were recruited for immunohistochemical analyses of CD9 expression in both tumor and stromal areas prior to statistical analyses to determine the prognostic impact and predictive accuracy of CD9.ResultsThe relationship between CD9 and prognostic indicators was not significant in the non‐neoadjuvant group. Nevertheless, CD9 expression in both tumor (T‐CD9) and stromal areas (S‐CD9) was significantly correlated with the clinicopathological features in the neoadjuvant group. High levels of T‐CD9 were significantly associated with worse OS (p = 0.005) and RFS (p = 0.007), while positive S‐CD9 showed the opposite results (OS: p = 0.024; RFS: p = 0.008). Cox regression analyses identified CD9 in both areas as an independent prognostic factor. The T&S‐CD9 risk‐level system was used to stratify patients with different survival levels. The combination of T&S‐CD9 risk level and TNM stage were accurate predictors of OS (C‐index: 0.676; AIC: 512.51) and RFS (C‐index: 0.680; AIC: 519.53). The calibration curve of the nomogram composed of the combined parameters showed excellent predictive consistency for 1‐year RFS. These results were verified using a validation cohort.ConclusionNeoadjuvant chemotherapy endows CD9 with a significant prognostic value that differs between tumor and stromal areas in patients with pancreatic cancer.  相似文献   
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