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71.
Ramesh S 《Clinical reviews in allergy & immunology》2008,34(2):217-230
Food allergies have increased significantly in the past decade. An accurate history is crucial in approaching the management.
At the outset, food intolerance must be distinguished from food allergies and, furthermore, these allergies should be classified
into either an IgE, Non-IgE, or a mixed response. The clinical features vary from life-threatening anaphylaxis to milder IgE-mediated
responses, atopic dermatitis, and gastrointestinal symptoms. The severity of the reaction and the potential risk for anaphylaxis
on reexposure should be assessed. Milk, soy, egg, wheat, and peanut allergies are common in children, whereas peanut, tree
nut, fish, shell fish allergies, and allergies to fruits and vegetables are common in adults. Structural proteins are important
determinants of the severity of the reactions and may often predict the natural history and cross reactivity. Diagnostic work
up must be guided by the clinical history. Skin testing and food-specific IgE done by standard methods are very useful, whereas
oral challenges may be indicated in some situations. Majority of the patients outgrow their allergies to milk, soy, egg, and
wheat, and some to peanut also, therefore, patients should be periodically reassessed. Novel diagnostic techniques which detect
specific allergenic epitopes have been developed. Several newer therapies are promising. 相似文献
72.
Extracts from plastrum testudinis (PTE), an important traditional Chinese medicine, have been demonstrated promotion of osteoblastic function in vitro. This study aims to investigate the protective effect of PTE on glucocorticoid-induced osteoporosis(GIOP) in vivo and analyze therapeutic targets of PTE on GIOP. SD rats were randomly assigned to two experiments: preventive and therapeutic experiments, in which rats respectively received oral PTE at the same time of glucocorticoid injection or after glucocorticoid injection inducing osteoporosis. BMD, microarchitecture, biomechanics, bone metabolism markers and histomorphology were evaluated. mRNA and protein expression of OPG, Runx2, CTSK and MMP9 were examined.Results showed bone quality and bone quantity were significantly elevated by PTE. Histomorphometry showed thicker and denser bone trabecularsand more osteoblasts and less osteoclasts in group of PTE intervention. The mRNA expression of OPG was significantly upregulated whereas expression of CTSK was significantly downregulatedin different groups of PTE intervention. Stronger immunostaining for Runx2 and weaker immunostaining for CTSK were observed in groups of PTE intervention. This demonstrated that PTE may reverse GIOP in prevention and management via targeting OPG, Runx2 and CTSK in mRNA and protein levels. 相似文献
73.
HPLC-ELSD-UV法同时测定氨酚那敏三味浸膏胶囊中长梗冬青苷、白花前胡甲素、白花前胡乙素 总被引:1,自引:0,他引:1
目的 建立氨酚那敏三味浸膏胶囊中长梗冬青苷、白花前胡甲素和白花前胡乙素的定量分析方法.方法 采用HPLC-ELSD-UV法测定长梗冬青苷、白花前胡甲素和白花前胡乙素,色谱柱为Venusil XBP-C18 (4.6 mm× 250 mm,5 μm),流动相为乙腈-水,梯度洗脱,体积流量为1.0 mL/min,紫外检测波长为320 nm;ELSD参数:漂移管温度为80℃,氮气体积流量为2.5 mL/min,雾化温度为36 ℃,柱温30℃.结果 长梗冬青苷在1.071 6~5.358 μg范围内的线性关系良好(r =0.999 1),平均回收率100.3%,RSD为2.05%(n=9);白花前胡甲素和白花前胡乙素分别在0.892 4~4.462 μg(r =0.999 9)和0.486 8~2.434 μg(r =0.999 7)范围内线性关系良好,平均回收率分别为100.03%、99.02%,RSD为2.01%、1.98%(n=9).结论 本方法测定结果准确可靠,重复性好,可为氨酚那敏三味浸膏胶囊的质量控制提供定量评价方法. 相似文献
74.
目的 比较家兔口服菊花提取物(CME)及其酸水解产物后,其效应成分(木犀草素和芹菜素)的动力学参数,阐明菊花黄 酮给药形式对其生物利用度的影响。方法 健康家兔单剂量(200mg·k-1)灌胃CME及其酸水解产物,以RP-HPLC测定给药 后不同时间点木犀草素和芹菜素血浆药物浓度。使用3P87软件拟合药动学参数,Microsoft Excel软件进行数据统计分析。结 果 家兔灌胃CME或其酸水解产物,血浆中木犀草素浓度较高,其药动学过程符合一室模型,血浆中芹菜素浓度在定量限以 下。两种形式给予家兔灌胃后,所得木犀草素药动学参数表明,与CME给药比较,以水解CME给家兔灌胃,木犀草素在其体 内的血药浓度达峰时间tmax滞后,最高血药浓度ρmax降低,而平均滞留时间MRT延长。结论 经Microsoft Excel软件统计分析, 以原型CME或水解CME给健康家兔灌胃,即CME中黄酮类化合物以苷或苷元的形式给药,在家兔体内的生物利用度无显著 性差异(P>0.05)。 相似文献
75.
76.
植物激素及生长调节剂对三七种子的效应 总被引:4,自引:0,他引:4
七种植物激素及生长调节剂对三七种子的处理结果,烯土、养植宝、三十烷醇等植物生长调节剂能明显提高三七出苗率,增加种苗产量。GA虽能打破三七种子休眠,使三七提前出苗,增加植株高度,但出苗率及产量均比对照明显下降。 相似文献
77.
Phase I clinical trial of O-acetylated pectin conjugate,a plant polysaccharide based typhoid vaccine
Background
Typhoid fever remains an important cause of morbidity and mortality in the developing countries. Vi capsular polysaccharide conjugate vaccine demonstrated safety and efficacy in young children in high endemic regions. A novel typhoid conjugate vaccine based on plant polysaccharide pectin was studied in a phase I trial.Methods
Fruit pectin, having the same carbohydrate backbone structure as Vi, was purified from citrus peel and used as the polysaccharide source to prepare a semi-synthetic typhoid conjugate vaccine. Pectin was chemically O-acetylated (OAcPec) to antigenically resemble Vi and conjugated to carrier protein rEPA, a recombinant exoprotein A from Pseudomonas aeruginosa. 25 healthy volunteers, 18–45 years old, were injected once with OAcPec-rEPA. Safety and IgG antibodies reactive with Vi and pectin were analyzed.Results
No vaccine associated serious adverse reaction was reported. Six weeks after the injection of OAcPec-rEPA, 64% of the volunteers elicited >4-fold rise of anti-Vi IgG. At 26 weeks the level declined, but the difference between the levels at 6 and 26 weeks are not statistically significant. There is a direct correlation between the level of anti-Vi IgG before and after the injection (R2 = 0.96). The anti-Vi IgG can be absorbed by Vi, but not by pectin. There was no corresponding increase of anti-pectin after the injection, indicating the antibody response to OAcPec-rEPA was specific to Vi. There is no Vi-rEPA data in US adults for comparison of immune responses. The OAcPec-rEPA elicited significantly less IgG anti-Vi in US adults than those by Vi-rEPA in Vietnamese adults.Conclusion
The O-acetylated pectin conjugate, a plant based typhoid vaccine, is safe and immunogenic in adult volunteers.ClinicalTrial.gov identifier: NCT00277147, NIH Protocol ID number: OH06-CH-0070, FDA BB Investigation New Drug (IND) number 6989. 相似文献78.
AIM OF THE STUDY: The present investigation was carried out to evaluate the safety of an aqueous extract of tansy (Tanacetum vulgare L.) leaves by determining its potential toxicity after acute and chronic administration in rodents. MATERIALS AND METHODS: For the acute study, a lyophilized aqueous extract of tansy leaves was administered to mice in single doses of 0-13 g/kg given by gavage as well as intraperitoneal doses of 0-4.5 g/kg. General behavior adverse effects and mortality were determined for up to 14 days. In the chronic dose study, the extract was administered orally at doses of 0, 100, 300 and 600 mg/kg daily for 90 days to rats. Biochemical and hematological parameters were determined after 30 and 60 days, and then at the end of 90 days of daily administration. RESULTS: In the acute study in mice, the crude aqueous extract of tansy leaves caused dose-dependent general behavior adverse effects and mortality. The no-observed adverse effect levels (NOAEL) of the tansy extract were 7.0 g/kg and 1.0 g/kg, and the lowest-observed adverse effect levels (LOAEL) were 9.0 g/kg and 1.5 g/kg, when given by the oral and intraperitoneal routes, respectively. Mortality increased with increasing doses, with LD(50) of 9.9 g/kg and 2.8 g/kg for the oral and intraperitonal modes of administration, respectively. In the chronic study in rats, daily oral administration of the crude aqueous extract of tansy leaves for up to 90 days did not result in death or significant changes in the biological (except for hypoglycemia) and hematological parameters. CONCLUSIONS: Because of the relatively high NOAEL values in the acute study in mice, and lack of significant effect on biological and hematological parameters in rats after 90 days of daily doses, the tansy extract does not appear to have significant toxicity. In view of the dose of tansy consumed in traditional medicine, there is a wide margin of safety for the therapeutic use of the aqueous extract of Tanacetum vulgare leaves. 相似文献
79.
目的 探讨银杏叶提取物(EGb761)对培养的人眼视网膜神经节细胞(RGC)的保护作用。方法 对照实验研究。将培养的人眼视网膜细胞分为对照组、谷氨酸组、EGb761组及谷氨酸+EGb761组,用Thy-1作为RGC特异性荧光抗体,以免疫流式细胞技术评价EGb761对人眼RGC的保护作用。多组间细胞存活率比较采用重复测量的方差分析,组间两两比较采用LSD t检验。结果 在不同干预因素作用下,RGC存活率呈现不同变化,对照组为(61.94±7.75)%,谷氨酸组为(44.59 +4.19)%,EGb761组为(75.05 +3.90)%,EGb761+谷氨酸组为(63.19±9.44)%;各组间RGC存活率比较差异有统计学意义(F=13.329,P<0.01)。各组与对照组RGC存活率两两比较,显示谷氨酸组RGC存活率降低(P =0.010),EGb761组RGC存活率升高(P=0.019),EGb761+谷氨酸组与对照组RGC存活率差异无统计学意义(P =0.801);与谷氨酸组相比EGb761组和EGb761+谷氨酸组RGC存活率明显升高(P=0.000,0.020)。死亡RGC中大RGC所占百分比,EGb761组为(24.63+7.21)%,EGb761+谷氨酸组为(25.99±5.05)%,与对照组(36.69±2.92)%比较,两组死亡RGC中大RGC所占百分比均降低(P=0.001,0.002);与谷氨酸组(40.78±3.34)%相比,两组大RGC死亡百分比亦降低(P =0.000,0.000)。结论 EGb761可对抗谷氨酸兴奋性毒性造成的RGC损伤,对体外培养的人眼RGC具有明显的保护作用。 相似文献
80.
岑王老山自然保护区药用植物资源分析 总被引:1,自引:0,他引:1
通过查阅相关文献,确定岑王老山自然保护区有药用植物186科666属1186种,并对保护区药用植物资源的特点进行了分析,提出了保护的建议和对策。 相似文献