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1.
S. Guerra  L. Allegra  F Blasi  M. Cottini 《Allergy》1998,53(9):863-869
The aim of our study was to analyze the clinical features, particularly the age at symptom onset, of allergic subjects (asthma and/or rhinitis) on the basis of the etiologic elements (sensitization to various allergens). We identified a group of monosensitized patients and a group of polysensitized patients. Within these groups, we identified subgroups of subjects monosensitized to one of the five main allergenic mixes (mites, Gramineae, trees, Parietaria, and Artemisia) and five subgroups of patients sensitized nonexclusively, that is, polysensitized, to the same allergens. The comparison between the two groups and among the various subgroups enabled us to conclude that:
  • 1)

    mono- and polysensitized patients present some clinical features so different as to constitute two clearly distinct clinical groups

  • 2)

    analysis of the clinical features associated with the sensitization to a specific allergen brings us to significantly different conclusions when we consider subgroups of monosensitized or polysensitized patients

  • 3)

    the parameter "age at symptom onset" shows great heterogeneity among both the mono- and the polysensitized subgroups - in particular, the great differences in mean age among the monosensitized subgroups (trees>y4rtemi.s(fl>Pflrie/flria>Gramineae>mites) appear very interesting and are open to various interpretative hypotheses

  • 4)

    unlike the polysensitized group, in the monosensitized group and subgroups, mean age is similar between men and women and, only for tree- and parietaria -monosensitive patients, also between asthmatic and rhinitic subjects.

  相似文献   
2.
Objective: To establish a high-performance liquid chromatographic method (HPLC) for the simultaneous determination of sixteen compounds from Artemisia ordosica. Methods: HPLC was used to analyze 16 quality indicators of A. ordosica. The HPLC conditions were as follows: Agilent Eclipse Plus C18 column (250 mm × 4.6 mm, 5 μm) with acetonitrile (A)-water (B) as mobile phase, gradient elution: 0?10 min, 75%?65% B; 10?30 min, 65%?35 % B; and finally 30?40 min, 35%?15% B. The flow rate was 1.0 mL/min, the column temperature was 40 °C, the injection volume was 10 μL, and monitored by absorbance at 285 nm for compounds 1?10, 12 and 225 nm for compounds 11, 13?16. Results: Under the selected experimental chromatographic conditions, compounds 1?16 showed good linearity (r > 0.9993) in a wide concentration range. Their average recoveries were 99.50%, 95.38%, 97.75%, 96.00%, 98.20%, 97.50%, 95.50%, 99.33%, 96.75%, 96.50%, 98.50%, 97.83%, 99.20%, 95.33%, 97.33% and 96.30%, respectively, and the RSD were 1.99%, 1.81%, 1.63%, 1.98%, 1.67%, 1.92%, 1.74%, 1.67%, 1.90%, 1.72%, 1.88%, 1.83%, 1.79%, 1.76%, 1.81% and 1.96%, respectively. Conclusion: Based on the results of the HPLC analysis, it was concluded that p-hydroxycinnamic acid (1), O-hydroxycinnamic acid (2), coniferyl alcohol (5), 5,4''-dihydroxy-7,3''-dimethoxyflavanone (8), 5,4''-dihydroxy-7-methoxyflavanone (9), 5-hydroxy-7,4''-dimethoxyflavanone (12), dehydrofalcarindiol (13), arteordoyn A (14), dehydrofalcarinol (15) and capillarin (16) are best suited for the role of quality indicators of A. ordosica grown in different ecological environments.  相似文献   
3.
The antioxidant activity ofArtemisia iwayomogi was determined by measuring the radical scavenging effect on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical The methanol extract ofA. iwayomogi showed strong antioxidant activity, and thus fractionated with several solvents. The antioxidant activity potential of the individual fraction was in the order of ethyl acetate>n-butanol>water>chloroform>n-hexane fraction. The ethyl acetate andn-butanol soluble fractions exhibiting strong antioxidant activity were further purified by repeated silica gel and Sephadex LH-20 column chromatography. Antioxidant chlorogenic acid was isolated as one of the active principles from then-butanol fraction, together with the inactive components, 1-octacosanol, scopoletin, scopolin, apigenin 7,4′-di-O-methylether luteolin 6,3′-di-O-methylether (jaceosidin), apigenin 7-methylether (genkwanin), 2,4-dihydroxy-6-methoxyacetophenone 4-O-β-D-glucopyranoside and quebrachitol. The antioxidant activity of chlorogenic acid was comparable to that of L-ascorbic acid, which is a well known antioxidant.  相似文献   
4.
茵陈提取液对实验性动物肝损伤的作用   总被引:4,自引:0,他引:4  
目的 研究茵陈提取液对实验性肝损伤的作用。 方法  用茵陈提取液连续给小鼠灌胃 7d后 ,采用四氯化碳 (CCL4 )腹腔内注射造成小鼠急性肝损伤 ,造型 2 0h后摘除眼球取血 ,测ALT、AST、ALP、TP、G、A等指标 :给大鼠每周二次皮下注射 10 %CCL4油液 0 .5ml/ 10 0g ,造成慢性肝损伤 ,于中毒第三个月初起开始 ,每日用茵陈提取液连续给大鼠灌胃一个月 ,于末次给药 2 4h眶静脉取血 ,分离血清 ,AT、AST、总蛋白、白蛋白、白蛋白 /球蛋白 (A/G)等指示。 结果 CCL4造成小鼠急性肝脏损伤 ,出现明显肝功能异常 ,茵陈提取液治疗组小鼠各项指标较CCL4模型组均有所降低 ,但差异无显著性意义 (P >0 .0 5 ) ;在CCL4所致大鼠慢性肝损伤模型中 ,茵陈提取液治疗组可显著地降低大鼠由CCL4造成的AST活性升高 ,与模型组比较 ,P <0 .0 1。 结论  茵陈提取液对CCL4所致大鼠慢性肝损伤有较好的治疗作用 ,但对CCL4造成小鼠急性肝伤模型没有保护作用。  相似文献   
5.
目的 :研究滨蒿花蕾的化学成分。方法 :各种色谱法分离纯化 ,波谱法鉴定结构。结果 :从干燥花蕾中分离得到 4个黄酮类化合物 ,鉴定为金丝桃苷 (Ⅴ ) ;泽兰黄酮 (Ⅵ ) ;胡麻素 (Ⅶ ) ;5 ,7,2′,4′-四羟基-6 ,5′- 二甲氧基黄酮 (Ⅷ )。结论 :化合物Ⅴ ,Ⅵ ,Ⅶ ,Ⅷ为首次从该植物中获得。  相似文献   
6.
滨蒿化学成分的研究(Ⅲ)   总被引:5,自引:0,他引:5  
目的 :研究滨蒿花蕾的化学成分。方法 :采用硅胶、聚酰胺、SephadexLH - 2 0柱色谱和高压液相色谱法分离化学成分 ,UV ,NMR和MS等方法进行结构鉴定。结果 :从干燥花蕾中又分离鉴定了 6个化合物 ,为 β-谷甾醇 (Ⅸ ) ,6 ,7-二甲氧基香豆素 (Ⅹ ) ,6-去甲基茵陈色原酮 (Ⅺ ) ,茵陈香豆酸乙 (Ⅻ ) ,华良姜素 ( ) ,异东莨菪苷 ( )。结论 :化合物Ⅺ ,Ⅻ , ,为首次从该植物中分离得到 ,其中化合物Ⅺ为一新化合物。  相似文献   
7.
News and Notes     
Abstract

The essential oil of nutmeg (600 or 900 mg/kg, IP) altered the young chicks' species-specific response to amphetamine (20 mg/kg, SQ). Nutmeg oil totally blocked the development of chirping and decreased the duration of wing droop and stereotyped behavior “b” (head and neck extended forward, parallel to but not touching floor), but increased the duration of stereotyped behavior “a” (head and neck drawn back with top of head almost touching back). Amphetamine caused a significant decrease in the duration of light and deep sleep in the group that received the higher dose level of nutmeg oil.  相似文献   
8.
目的 制备高纯度3,5-O-二咖啡酰基奎宁酸,并评价其对人宫颈癌HeLa细胞的抗增殖活性。方法 采用柱色谱提取法和中压液相色谱法从奇蒿花中分离、纯化得到高纯度的3,5-O-二咖啡酰基奎宁酸。采用MTT法评价该化合物对人宫颈癌HeLa细胞的体外抗增殖活性。结果 柱色谱提取的提取率和中压液相色谱法的回收率分别为99.0%,61.2%,总回收率为54.0%。随着3,5-O-二咖啡酰基奎宁酸浓度升高,HeLa细胞存活率下降,细胞形态损伤增加,受试药物的IC50值为26.5µg·mL-1结论 本研究提供了一种简单、高效、节能的3,5-O-二咖啡酰基奎宁酸制备方法。3,5-O-二咖啡酰基奎宁酸对HeLa细胞具有一定的体外抗增殖活性。  相似文献   
9.
目的:对10批茵陈的质量进行质量分析比较。方法:薄层色谱法对茵陈进行鉴别,高效液相色谱法测定茵陈主要成分绿原酸的含量。结果:10批茵陈按薄层色谱鉴别均为合格,绿原酸的含量分别为:甘肃0.62%;山东0.13%;宁夏1.10%;安徽0.72%;河北0.28%;四川0.60%;陕西1.50%;河南0.47%;湖南0.70%;山西1.40%。结论:宁夏、陕西、山西产茵陈质量最佳,山东、河北、河南产茵陈绿原酸含量达不到中国药典的标准,本试验结果可为生产厂家优选货源提供参考。  相似文献   
10.
The purpose of the present study was to investigate hypolipidemic and anti-inflammatory effects of Artemisia vulgaris extract in hypercholesterolemic rats. Hypercholesterolemia was induced by feeding of rats with high fat diet containing 3% cholesterol in olein oil, for 8 weeks. Feeding of rats with high fat diet for 8 weeks, leading to a significant increase in serum triglycerides, total cholesterol, low density lipoprotein cholesterol, malondialdehyde and nitric oxide, tumor necrosis factor-α levels and a significant decrease in serum high density lipoprotein cholesterol level, liver hydroxymethylglutaryl-CoA reductase activity and paraoxonase-1 activities as compared to the normal control group. Treatment of high fat diet rats with Artemisia vulgaris extract for 4 weeks at a dose of 100 mg/kg per day, resulted in normalized serum lipid profile, a significant increase in paraoxonase-1 activity and decrease in serum malondialdehyde, nitric oxide and tumor necrosis factor-α level as compared to high fat diet-treated animals. Also the extract caused a significant decrease in hydroxymethylglutaryl-CoA reductase activity as compared with both high fat diet-treated animals and control ones. In conclusion, Artemisia vulgaris extract has hypolipidemic, anti-inflammatory, antioxidant properties; it may serve as a source for the prevention of atherosclerosis and cardiovascular diseases.  相似文献   
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