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51.
强化婴幼儿奶粉中叶酸的测定 总被引:1,自引:0,他引:1
强化叶酸的奶粉在0.05M K_2HPO_4缓冲液中,经均质,调pH4.5,15000g离心20分钟,其清液调pH4.0,进行CGS树脂离子交换层析,用10ml KClK_2HPO_4洗脱,调pH7.0,进行HPLC测定,采用300x3.9mm ODS反相柱,移动相0.05M K_2HPO+MeOH(91+9),流速1ml/分,紫外检测器波长285nm,灵敏度0.0050D。方法相对标准偏差为±3.3%,回收率为87%,最小检测量为0.02μg/ml。 相似文献
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Xiao Er Ke Chuan Ling Oral Liquid (KCL) is a Chinese herbal preparation consisted of 10 herbs such as Prunus armeniacae, Scutelaria baicalensis, Lonicera japonica etc. 30 children suffering from bronchopneumonia and/or acute bronchitis were treated with KCL (treated group) and another 30 cases were treated with penicillin and aminophylline (control group). Results: cure rate and effective rate in treated group was 26.6%, and 93.3% respectively. While in control group was 30% and 96.6% respectively. No significant differences were seen between them(P > 0.05). The pharmacodynamic experiment showed KCL had potent pharmacological action. The experiment on tracheal fragment of Guinea pig in vitro showed it caused moderately strong smooth muscle relaxation, through inhibition the effect of histamine and acetylcholine. Asthma induction experiment of Guinea pig in vivo showed KCL could significantly prolong the latent period of asthma and alleviate asthmatic symptom. Ammonium water cough induction experiment in mice showed it may apparently prolong cough latent period and reduce times of cough relapse and alleviate cough symptom. KCL had potent antipyretic effect on fever model induced by triple vaccine in rabbits. Bacteriostatic and antiviral experiment in vitro showed the drug had quite strong inhibitory effects for Streptococcus hemolyticus, Staphylococcus aureus, Flexners Dysentery bacillus, Diplococcus pneumoniae and Pseudomonas aeruginosa, and it could potently inhibit the respiratory syncytial virus. KCL is an effective drug in treating bronchopneumonia and acute bronchitis. 相似文献
54.
Viral markers were studied in 79 cases of viral hepatitis with hepatic failure. The results were shown as follows: 8 cases were positive for anti-HAV IgM (10.12%); 76 cases positive for HBsAg or anti-HBc IgM (96.20%) and 41 cases positive for anti-HCV antibodies (51.89%). Among those with anti-HCV positive, 35 cases were co-infected with HBV, 5 cases with HAV and/or HCV, only one was infected with HCV alone 2 cases were HD-Ag positive (2.52%) and one not identified (1.27%). With the reference of clinical findings, patients co-infected with HBV/HCV or anti-HBc IgM positive were more critical and usually entail higher mortality. In cases with HCV co-infections, the positive HBV replication markers seems to be reduced. Hepatic failure without HBV replicative markers had a high rate of hepatic coma as well as poor outcome. 相似文献
55.
影响脐血IgE值因素的研究 总被引:2,自引:0,他引:2
目的 本研究对影响脐血IgE值的可疑因素进行分析 ,探讨影响儿童食物过敏的可疑因素。方法 选取孕期妇女 10 5名及其所生婴儿 ,采用标准问卷调查获取资料 ,对影响脐血IgE的因素进行分析。 结果 母亲的过敏性疾病史、父亲过敏性疾病史中的皮炎表现型、孕期妇女过敏性疾病发作史、有过敏史妇女孕后期摄入过量的牛奶和鸡蛋均与脐血IgE值的上升有关 ,且上述 5个因素对脐血IgE水平的影响依次降低。 结论 母亲的过敏性疾病史和父亲过敏性疾病史中的皮炎表现型是导致新生儿脐血IgE值升高的主要危险因素 ;同时 ,妊娠期加强对有过敏史妇女的保护 ,防止过敏性疾病的复发 ,在孕后期控制有过敏史妇女牛奶、鸡蛋等大分子食物致敏原的摄入 ,有助于降低脐血IgE值。 相似文献
56.
目的 :探讨外周血单个核细胞 (PBMC)内上游信号分子及核因子 κB(NF κB)在烧伤后炎症级联反应中的作用。 方法 :体外检测在烧伤血浆作用下的PBMC内游离Ca2 及NF κB活化的变化 ,观察钙通道阻断药对NF κB活化及IL 6、NO表达水平的调控作用。 结果 :不同时相点的烧伤血浆可使体外PBMC内Ca2 明显增加 ,培养的PBMC核内NF κB的积聚明显增加 ,培养上清中NO和IL 6高表达。应用尼莫通 (Nimodipine)和丹曲林 (Dantrium)对NF κB的活化有调节作用 ,对IL 6和NO亦有下调作用。 结论 :烧伤血浆可使PBMC内信号分子浓度明显增高 ,NF κB过度活化 ,并易位进入细胞核内 ,NF κB介导的促炎性细胞因子和NO过度表达。两种钙通道阻断药有调控细胞内信号转导的作用 ,对烧伤后全身炎症反应综合征 (SIRS)可能有防治作用 相似文献
57.
浅谈基因治疗的现状及其面临的困境 总被引:1,自引:0,他引:1
基因治疗将在未来的疾病治疗中扮演重要的角色,然而这一新颖的技术却面临着诸多问题,本文论述了基因治疗的发展现状及其所面临的技术难题。 相似文献
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59.
A difference spectrophotometric procedure is described for the assay of nitrazepam in tablet formulations. The method is based on the measurement of absorbance at 282 nm of a solution of the tablet extract in 0.1 M hydrochloric acid (pH 1) relative to that of an equimolar solution in 0.1 M sodium hydroxide (pH 13). The method is precise and selective for nitrazepam in the presence of the tablet excipients and 2-amino-5-nitrobenzophenone, the principal hydrolysis product of nitrazepam. The absence of a constant isosbestic point in the difference spectrum of nitrazepam during hydrolysis in alkaline solution indicates the presence of a previously unrecognized intermediate hydrolysis product. 相似文献
60.
豚鼠内耳磁微粒栓塞缺血模型初探 总被引:3,自引:0,他引:3
OBJECTIVE: To set up an inner ear ischemic model in guinea pig with ferromagnetic embolism. METHODS: A magnet was fitted in the external auditory canal and carbonyl iron filings (1%, 1 ml/kg) was injected into jugular, then the inner ear vessels were obstructed by ferromagnetic spheres. Cochlear blood flow (CBF) and number of red blood cells in the stria vessels were used to detect the model's ischemia of cochleae. The slice of temple bone and basal membrane stained by silver nitrate were used for inner ear's histopathological observations. RESULTS: The iron spheres were amassed in the one and two-day-later's model of inner ear vessels, which resulted in embolism. The number of red blood cells in the stria vessels decreased and then recovered to normal level after 4 days, but the CBF decreased to 50% +/- 10% of basic level immediately and recovered to 99% +/- 41% 4 days later. Scattered lesion of out hair cell cilium could be seen in cochleae in eight-day-later's model, and degenerations in different degree were found in vascular stria. CONCLUSION: The methods of inner ear ischemic model with ferromagnetic embolism could be practical and the decrease of CBF was reversible, so it may be an ideal model for studying some ischemic inner ear diseases and evaluating the effects of therapeutic drugs. 相似文献