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21.
Ninety-one high atopy-risk infants were prospectively followed up to 18 months of age with regard to the development of allergic/atopic manifestations and sensitization. They were randomized into one of two feeding groups, i.e., a hydrolyzed, ultrafiltered cow's milk whey formula, Profylac® ( n = 32), or an ordinary cow's milk formula ( n = 39), for 12 months, started after exclusive breast-feeding for 0–9 (median 6.0) months. Lactating mothers avoided milk, egg, and fish, as did the infants up to 12 months of age. Twenty of the 91 infants were breast-fed exclusively for more than 9 months and regarded as a control group. All infants were followed-up by questionnaires, physical examinations, skin prick tests, and determination of serum total IgE and cow's milk-specific IgE. The frequency of allergic/atopic disease was similar in the three groups. However, all three infants who developed cow's milk allergy with skin symptoms belonged to the cow's milk formula group. The skin prick test with whey hydrolysate was negative in all, while with cow's milk it was positive in eight infants. Growth was similar in the three groups. The study comprises too few infants to allow us to make statistically based statements. However, the difficulties encountered and the limited effects obtained by the use of whey hydrolysate at weaning at about 6 months of age made us conclude that we can spare high atopy-risk families this extra burden.  相似文献   
22.
We developed a sensitive sandwich-type ELISA for measuring low levels of cow's milk (CM) β-lactoglobulin. Purified anti-β-lactoglobulin was used as coating antibody and also as second antibody conjugated with alkaline phosphatase. Polyethylene glycol 6000 was added to the incubation buffers to improve sensitivity. The detection limit of the assay was 0.002 μg/l, which is much better than sensitivities reported for other β-lactoglobulin assays. The sensitivity was not impaired by the presence of other CM proteins. The recovery from breast milk was 93% and from the diluting buffer 127%. The coefficient of variation within day was 5–15% and between days 10%. One hour after oral intake of milk, P-lactoglobulin could be detected in the breast milk of three mothers at concentrations of about 1–2 μg/l. Widely different concentrations of β-lactoglobulin were measured in two protein hydrolysates based on CM whey and casein proteins; the observed concentrations were 200 and 0.0056 μg P-lactoglobulinμ/g dry weight, respectively.  相似文献   
23.
Fuzzy rules to predict degree of malignancy in brain glioma   总被引:2,自引:0,他引:2  
The current pre-operative assessment of the degree of malignancy in brain glioma is based on magnetic resonance imaging (MRI) findings and clinical data. 280 cases were studied, of which 111 were high-grade malignancies and 169 were low-grade, so that regular and interpretable patterns of the relationships between glioma MRI features and the degree of malignancy could be acquired. However, as uncertainties in the data and missing values existed, a fuzzy rule extraction algorithm based on a fuzzy min-max neural network (FMMNN) was used. The performance of a multi-layer perceptron network (MLP) trained with the error back-propagation algorithm (BP), the decision tree algorithm ID3, nearest neighbour and the original fuzzy min-max neural network were also evaluated. The results showed that two fuzzy decision rules on only six features achieved an accuracy of 84.6% (89.9% for low-grade and 76.6% for high-grade cases). Investigations with the proposed algorithm revealed that age, mass effect, oedema, post-contrast enhancement, blood supply, calcification, haemorrhage and the signal intensity of the T1-weighted image were important diagnostic factors.  相似文献   
24.
目的:分析地黄在中药类保健食品中生熟异用下的配方规律。方法:收集国家市场监督管理总局(SAMR)特殊食品信息查询平台公布的生、熟地黄保健食品数据,对其保健功能及中药组方等进行统计,运用Apriori算法和Kulc、不平衡比参数对地黄生熟异用的保健食品配方规律进行分析。结果:保健食品中,生地黄主要用于辅助降血糖,熟地黄主要用于增强免疫力、缓解体力疲劳、改善营养性贫血。在辅助降血糖类生地黄保健食品中,生地黄主要与补气药、补阴药、解表药、解热药配伍,代表性组合为生地黄-黄芪-苦瓜;在增强免疫力类熟地黄保健食品中,熟地黄主要与补气药、补血药、补阴药配伍,代表性组合为熟地黄-党参-阿胶;在缓解体力疲劳类熟地黄保健食品中,熟地黄主要与补气药、补阳药、补阴药配伍,代表性组合为熟地黄-人参-淫羊藿、熟地黄-人参-枸杞子;在改善营养性贫血类熟地黄保健食品中,熟地黄主要与补气药、补血药配伍,代表性组合为熟地黄-黄芪-阿胶、熟地黄-黄芪-当归。结论:地黄在保健食品中的使用遵循生熟异用的规律,在不同保健功能中,组方配伍基本符合中医理论和现代医学理论,可为生、熟地黄保健食品研发提供借鉴和依据。  相似文献   
25.
山药配方颗粒由山药饮片经水煎煮提取、分离、浓缩、干燥、制粒而成,具有调剂简单、使用方便、免煎易服等优势。然而,因山药富含淀粉与黏液质类成分,其提取物粉末与配方颗粒溶化性差,在5 min内难以完全溶化或分散,不溶物即使在水中静置24 h也难以完全溶散,影响了配方颗粒的质量评价与患者的服药心理。因此,通过研究山药提取物及其配方颗粒的溶化过程与机制,发现山药特殊的化学组成、高温提取过程中淀粉的变性及其与蛋白质等物质的复合、喷雾干燥过程中“衣膜”的收缩形成等因素综合叠加,最终形成“衣膜”包覆淀粉粒的特殊微观结构,是山药配方颗粒溶化性差的根本原因。基于课题组前期对粉体结构-性质-功能的研究,笔者提出采用粉体改性工艺改善山药配方颗粒溶化性的技术策略,并通过实验证明改性处理后的山药配方颗粒能在2 min内实现全部溶散,解决了该技术难题,可为其他类似品种的溶化性改善提供借鉴,推动中药配方颗粒产业的高质量发展。  相似文献   
26.
阿尔茨海默病(AD)是最常见的痴呆形式,目前缺少疾病修饰性的治疗药物。中医理论认为肾精亏虚是AD发生发展的内在机制,补肾益精是中医治疗AD的基本原则,贯穿AD治疗的始终。补肾益智方是治疗AD的临床经验方。补肾益智方治疗AD已有大量文献报道,但补肾益智方缺乏临床应用安全性评价,同时其基础研究薄弱,有效成分不明、多靶点作用机制不清。为阐明补肾益智方多成分、多靶点、多途径治疗AD的作用机制,该文综述了补肾益智方治疗AD的研究进展。进一步收集了16个基于高效液相色谱指纹图谱的补肾益智方主要化学成分,并对其成药性与安全性进行评价。利用基于AD重要病理生理学过程的网络药理学与文献综述相结合的方法,深入分析了补肾益智方靶向胆碱能系统、AD神经病理学特征的有效成分及可能机制。该研究为AD对症治疗、疾病修饰性治疗的药物研发提供了一系列有潜力的先导化合物,并为深入拓展补肾益智方的临床应用提供了理论依据。  相似文献   
27.
目的 探讨慢溃宁方对葡聚糖硫酸钠(DSS)诱导的溃疡性结肠炎(UC)小鼠肠道菌群的调控作用,和对NOD样受体(NLR)P3/胱天蛋白酶(Caspase)-1/Gasdermin D(GSDMD)细胞焦亡通路所介导炎症的影响。方法 SPF级C57BL/6小鼠60只,随机分为空白组、模型组、慢溃宁方组(20 g·kg-1)、美沙拉秦组(0.266 g·kg-1),各组15只。小鼠通过自由饮用3%DSS溶液,7 d构建UC模型。造模开始12 h后,治疗组每天灌胃给药,其余组灌胃等体积生理盐水。记录小鼠每日体质量等情况,并评估计算疾病活动指数(DAI)。第8天麻醉后,脱臼颈椎处死小鼠,收集结肠和粪便,记量结肠长度;观察结肠组织苏木素-伊红(HE)染色后的病理学改变;结肠中肿瘤坏死因子-α(TNF-α)、白细胞介素-1β(IL-1β)、白细胞介素-18(IL-18)水平用酶联免疫吸附测定法(ELISA)检测;基于16S rRNA测序技术检测各组小鼠粪便中肠道菌群的差异;NLRP3/Caspase-1/GSDMD蛋白结肠组织中含量用蛋白免疫印迹法(Western blot)检测。结果 相较于空白组,模型组小鼠的DAI升高(P<0.01),结肠长度显著缩短(P<0.01),结肠黏膜损伤严重,TNFα、IL-1β、IL-18水平均明显升高(P<0.01),且结肠组织中NLRP3/Caspase-1/GSDMD蛋白含量显著升高(P<0.01),肠道菌群结构改变,门水平上的放线菌门、拟杆菌门与变形菌门丰度减少,厚壁菌门丰度增加;属水平上的乳酸杆菌、普雷沃氏菌和鼠杆菌属丰度减少,拟杆菌属、芽孢杆菌、毛螺旋菌属NK4A136丰度增加。慢溃宁方组、美沙拉秦组相较于模型组,第3天后DAI显著降低(P<0.01),结肠长度均显著增加(P<0.01),结肠的炎症浸润及黏膜结构损伤减轻,且结肠TNF-α、IL-1β、IL-18水平均显著下降(P<0.01),NLRP3/Caspase-1/GSDMD蛋白在结肠组织中的含量明显降低(P<0.05,P<0.01),门水平上的变形菌门和拟杆菌门丰度增加,厚壁菌门丰度减少。结论 慢溃宁方可通过抑制细胞经典焦亡通路,缓解UC小鼠结肠炎症反应,减轻结肠损伤,并对肠道菌群紊乱有改善作用。  相似文献   
28.
Cow’s milk protein allergy (CMPA) is associated with dysbiosis of the infant gut microbiome, with allergic and immune development implications. Studies show benefits of combining synbiotics with hypoallergenic formulae, although evidence has never been systematically examined. This review identified seven publications of four randomised controlled trials comparing an amino acid formula (AAF) with an AAF containing synbiotics (AAF-Syn) in infants with CMPA (mean age 8.6 months; 68% male, mean intervention 27.3 weeks, n = 410). AAF and AAF-Syn were equally effective in managing allergic symptoms and promoting normal growth. Compared to AAF, significantly fewer infants fed AAF-Syn had infections (OR 0.35 (95% CI 0.19–0.67), p = 0.001). Overall medication use, including antibacterials and antifectives, was lower among infants fed AAF-Syn. Significantly fewer infants had hospital admissions with AAF-Syn compared to AAF (8.8% vs. 20.2%, p = 0.036; 56% reduction), leading to potential cost savings per infant of £164.05–£338.77. AAF-Syn was associated with increased bifidobacteria (difference in means 31.75, 95% CI 26.04–37.45, p < 0.0001); reduced Eubacterium rectale and Clostridium coccoides (difference in means −19.06, 95% CI −23.15 to −14.97, p < 0.0001); and reduced microbial diversity (p < 0.05), similar to that described in healthy breastfed infants, and may be associated with the improved clinical outcomes described. This review provides evidence that suggests combining synbiotics with AAF produces clinical benefits with potential economic implications.  相似文献   
29.
The present study aims to evaluate the effects of an infant formula supplemented with a mixture of prebiotic short and long chain inulin-type oligosaccharides on health outcomes, safety and tolerance, as well as on fecal microbiota composition during the first year of life. In a prospective, multicenter, randomized, double-blind study, n = 160 healthy term infants under 4 months of age were randomized to receive either an infant formula enriched with 0.8 g/dL of Orafti®Synergy1 or an unsupplemented control formula until the age of 12 months. Growth, fever (>38 °C) and infections were regularly followed up by a pediatrician. Digestive symptoms, stool consistency as well as crying and sleeping patterns were recorded during one week each study month. Fecal microbiota and immunological biomarkers were determined from a subgroup of infants after 2, 6 and 12 months of life. The intention to treat (ITT) population consisted of n = 149 infants. Both formulae were well tolerated. Mean duration of infections was significantly lower in the prebiotic fed infants (p < 0.05). The prebiotic group showed higher Bifidobacterium counts at month 6 (p = 0.006), and higher proportions of Bifidobacterium in relation to total bacteria at month 2 and 6 (p = 0.042 and p = 0.013, respectively). Stools of infants receiving the prebiotic formula were softer (p < 0.05). Orafti®Synergy1 tended to beneficially impact total daily amount of crying (p = 0.0594). Supplementation with inulin-type prebiotic oligosaccharides during the first year of life beneficially modulates the infant gut microbiota towards higher Bifidobacterium levels at the first 6 months of life, and is associated with reduced duration of infections.  相似文献   
30.
提出了将“前-后实验”和“连续实验”两种催速失活的实验方法结合起来的一种新的催化剂活性评价方法,可以较短的实验时间内,获得该催化剂比较全面、完整的活性衰退的信息。使用该评价方法,对ZSM-5分子筛催化剂AB-97催化苯与乙烯的烷基化反应的失活规律进行了实验研究,结果表明:在缓和条件与苛刻条件下,催化剂的失活规律有所不同。在实验基础上,结合Monte-Carlo模拟的方法,对此进行了机理分析,发现在不同的反应条件下,反应物在催化剂晶粒表面上吸附位置以及反应机理均不相同,同时证实了实验结果。  相似文献   
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