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71.
抗性家蝇蛹期多肽的双向电泳分析 总被引:5,自引:0,他引:5
分析抗性家蝇蛹期多肽,以了解蛋白质变化情况。方法:对家蝇的抗性株、对照株和敏感株蛹体内的多肽进行了聚丙烯酸胺凝胶电泳分析。结果:抗性株具有一特异的多肽点,且有3个多肽点在量上明显多于对照株。结论:杀虫剂的作用可使抗性家蝇体内的蛋白在质和量上发生改变。 相似文献
72.
目的 分离和纯化母婴血型不合母体的特异性高效价的IgG抗体。方法 采用半饱和硫酸铵低温沉淀法分离IgG抗体,SephedexA50层析柱纯化,然后用B型红细胞(RBC)吸收放散IgG,用聚乙二醇(PEG)沉淀,真空泵脱水回收IgO。结果 200ml血浆经半饱和硫酸铵低温沉淀后得IgG粗制品2.26g,Sephedex A50层析柱纯化后得纯制品1.84g,经B型RBC吸收放散后得特异性IgG 0.55g,回收率达29.89%(0.55/1.84)。结论 采用半饱和硫酸铵低温沉淀法分离高效价IgG抗体,可以获得高纯度的IgG。 相似文献
73.
A Single-Blind, Crossover Comparison of the Pharmacokinetics and Cognitive Effects of a New Diazepam Rectal Gel with Intravenous Diazepam 总被引:3,自引:1,他引:2
Summary: Purpose: The objective of this study was to compare the pharmacokinetics and cognitive effects of a new diazepam (DZP) rectal gel (Diastat®) with intravenously administered DZP.
Methods: Twenty healthy volunteers were enrolled in a single-blind, randomized, double-dummy, two-period, crossover study. Subjects received either 15 mg of DZP rectal gel or 7.5 mg of DZP by intravenous infusion. Blood samples for DZP and desmethyldiazepam analysis were obtained before the dose and from 3 min to 240 h after the dose. Heart rate and blood pressure were measured over the first 24-h period. Subjects also completed five repetitions of a neuropsychological test battery over the first 8-h period.
Results: Diazepam rapidly appeared in plasma after rectal administration, exceeding 200 ng/mL within 15 min and reaching an initial maximum of 373 ng/ml at 45 min and a second maximum of 447 ± 91.1 ng/ml at ∼70 min. The absolute bioavailability of DZP rectal gel was 90.4%. Subjects receiving intravenous DZP were less alert and performed less efficiently on the WAIS Digit Symbol test 6 min after the dose. Subjects receiving DZP rectal gel performed less well on the WAIS Digit Span test 1 h after the dose and required more time to complete the Letter Cancellation and Grooved Pegboard tests 1 and 2 h after drug administration.
Conclusions: Diastat® displayed rapid, consistent absorption and was well tolerated. Alterations in cognition were mild and dissipated within 4 h of drug administration. This new rectal drug-delivery system offers an easy, safe, and bioavailable method to administer DZP. 相似文献
Methods: Twenty healthy volunteers were enrolled in a single-blind, randomized, double-dummy, two-period, crossover study. Subjects received either 15 mg of DZP rectal gel or 7.5 mg of DZP by intravenous infusion. Blood samples for DZP and desmethyldiazepam analysis were obtained before the dose and from 3 min to 240 h after the dose. Heart rate and blood pressure were measured over the first 24-h period. Subjects also completed five repetitions of a neuropsychological test battery over the first 8-h period.
Results: Diazepam rapidly appeared in plasma after rectal administration, exceeding 200 ng/mL within 15 min and reaching an initial maximum of 373 ng/ml at 45 min and a second maximum of 447 ± 91.1 ng/ml at ∼70 min. The absolute bioavailability of DZP rectal gel was 90.4%. Subjects receiving intravenous DZP were less alert and performed less efficiently on the WAIS Digit Symbol test 6 min after the dose. Subjects receiving DZP rectal gel performed less well on the WAIS Digit Span test 1 h after the dose and required more time to complete the Letter Cancellation and Grooved Pegboard tests 1 and 2 h after drug administration.
Conclusions: Diastat® displayed rapid, consistent absorption and was well tolerated. Alterations in cognition were mild and dissipated within 4 h of drug administration. This new rectal drug-delivery system offers an easy, safe, and bioavailable method to administer DZP. 相似文献
74.
Human lymphocytes (HL) as well as lymphocytes (RL), hepatocytes (RH), and gastric mucosa cells (GM) of Sprague-Dawley rats were treated in vitro for 1 h with methylmercury chloride (MMC, 0.5–4 μg/ml) and dimethylmercury (DMM, 5–40 μg/ml). The cytotoxicity of the two organic mercury compounds was assessed by dye exclusion, and the extent of induced DNA fragmentation was measured with a single-cell microgel electrophoresis assay. Both MMC and DMM induced DNA damage and cytotoxicity in a dose-related manner in HL, RL, and GM. MMC was more effective in causing a significant increase in median DNA migration than DMM at doses yielding approximately the same degree of cytotoxicity. In rat hepatocytes the MMC-induced DNA damage was, however, lower than in the other cells. An analysis of repair kinetics following exposure to 2 μg/ml MMC was carried out in human lymphocytes obtained from an adult male donor. The bulk of DNA repair occurred 90 min after in vitro exposure, and it was about complete by 120 min following cessation of exposure. Finally, in order to have a basis for extrapolating to the human situation, in vivo studies were performed with Sprague-Dawley rats, also assessing the DNA damage and cytotoxicity in the lymphocytes and gastric mucosa cells. These in vivo results after oral exposure may be directly compared to the in vitro data obtained in the same cells. © 1993 Wiley-Liss, Inc. 相似文献
75.
[目的] 研究三七总皂苷眼用凝胶在兔眼组织的药物分布。[方法] 选取12只新西兰大白兔,随机分为4组,每组3只兔子。每只兔眼分别给予凝胶41.67 μL/kg(即三七皂苷R1 0.132 mg/kg,人参皂苷Rg1 0.452 mg/kg)。给药后于0.5、1、1.5、2 h空气栓塞各处死1组兔子。取眼球,分离各眼组织。采用UPLC-MS检测不同时间点各眼组织的药物含量。[结果] 兔眼给予三七总皂苷眼用凝胶后,三七皂苷R1在兔角膜、晶状体、房水、玻璃体中的最大含量分别为13.16、1.16、0.86、0.10 μg/g,人参皂苷Rg1在角膜、晶状体、房水、玻璃体中的最大含量分别为38.49、4.50、3.38、0.28 μg/g。[结论] 三七总皂苷眼用凝胶滴到兔眼后,三七皂苷R1和人参皂苷Rg1可透过角膜分散到各眼组织。在0~2 h内,各眼组织中的药物含量由高到低依次为角膜、晶状体、房水、玻璃体,表明三七皂苷R1和人参皂苷Rg1可透过角膜,到达眼后部组织,在2 h时各眼部组织的药物含量依然较高,在眼组织的保留时间长。 相似文献
76.
Terry M. Maloney Philip L. Paine Jose Russo 《Breast cancer research and treatment》1989,14(3):337-348
Summary The protein populations of epithelial cells cultured from two neoplastic and five non-neoplastic human breast tissues were resolved and displayed by two-dimensional polyacrylamide gel electrophoresis and silverstaining. With a computer-based image analysis system, we identified eight polypeptides which are present in both of the neoplastic cell lines, but absent from all five of the cultures of non-neoplastic breast cells. The eight polypeptides are not unique to cells cultured from neoplastic breast, because they are also found in cells cultured from non-breast tissues, both neoplastic and non-neoplastic. Two of the eight polypeptides ( Mr 25,000/pI 4.4 and Mr 31,000/pI 5.5) are present in the patterns of whole tissue samples from infiltrating ductal carcinomas and absent in most normal breast tissue. 相似文献
77.
Wang L Zhu YF Guo XJ Huo R Ma X Lin M Zhou ZM Sha JH 《Journal of molecular medicine (Berlin, Germany)》2005,83(10):812-821
The ovary plays a central role in oogenesis and gonadal hormone secretion. Proteomic analysis is a valuable approach for gaining an increased understanding of the molecular nature of the ovary. In this work, two-dimensional electrophoresis for protein separation followed by matrix-assisted laser desorption/ionization mass spectrometry and database searches, identified 231 protein spots corresponding to 138 individual proteins that were found in gels representing both the follicular and luteal phases. The data were used to construct a database online (). The identified proteins were functionally classified into seven groups: (1) cell signaling/communication, (2) cell division, (3) gene/protein expression, (4) metabolism, (5) cell structure and motility, (6) cell/organism defense, and (7) unclassified. Among the proteins identified, 47% had not been previously reported in the human ovary. In addition, a number of disease-related proteins were identified in this protein map, including some cancer- and polycystic ovarian syndrome-related proteins. Two proteins with phosphorylation were verified by Western blot analysis. Comparison of protein abundance between follicular and luteal stages produced seven protein spots that had been identified in our database. This study provides a preliminary reference map of normal human ovary that will form a basis for comparative studies on normal and pathological conditions of the human ovary and may serve as a potential tool for clinical diagnosis, therapeutics, and prognosis.Electronic Supplementary Material Supplementary material is available in the online version of this article at L. Wang and Y.-F. Zhu contributed equally to this work 相似文献
78.
金属表面TiO2薄膜的溶胶-凝胶法制备及其血液相容性研究 总被引:8,自引:1,他引:8
通过溶胶 凝胶法制备TiO2 薄膜对 316L不锈钢和NiTi形状记忆合金进行表面改性处理。研究发现 ,经 5 0 0℃处理 1h的薄膜结构致密 ,膜层均匀平滑 ,薄膜主要由锐钛矿相TiO2 构成 ,随热处理温度的提高 ,锐钛矿相逐渐转变为金红石相。电化学腐蚀和动态凝血时间及溶血率测试表明 ,通过溶胶 凝胶法制备TiO2 膜进行表面改性的 316L不锈钢和NiTi合金的抗模拟体液腐蚀性提高 ,动态凝血时间延长 ,溶血率下降 ,说明溶胶 凝胶法制备TiO2 膜可以提高金属植入物的血液相容性 相似文献
79.
BACKGROUND: Cypress pollen allergy is a major cause of rhinoconjunctivitis and asthma in the Mediterranean area. The nonstandardized cypress allergen extracts currently available for the diagnosis of cypress allergy have a low level of activity. The search for an active material has led to the selection of Juniperus ashei (Ja) pollen because of its very high cross-reactivity with cypress extracts and its superior allergenic activity. The aim of this study was to characterize in vitro and calibrate in vivo an in-house reference extract (IHRS) of J. ashei pollen and determine the specificity and sensitivity of a standardized Ja extract for the prick test diagnosis of cypress allergy. METHODS: Juniperus ashei pollen extract was analysed by 2-D electrophoresis. The IHRS Ja extract was calibrated by skin prick testing in 28 cypress-allergic patients. The sensitivity and specificity of cypress allergy diagnosis using a standardized Ja extract was studied by skin prick test in 42 cypress-allergic patients and 53 nonallergic patients. Jun a 1 content of the IHRS was determined by a monoclonal antibody-based electrophoretic technique. RESULTS: The Jun a 1 content of the 100 IR/ml Ja IHRS extract was 180 microg/ml. For in vivo diagnosis of cypress allergy, Ja pollen extract demonstrated a sensitivity of 95%, a specificity of 100%, a negative predictive value of 96%, and a positive predictive value of 100%. CONCLUSION: Standardized Ja pollen extract is therefore a very appropriate tool for the in vivo diagnosis of cypress pollen allergy and good candidate for specific immunotherapy. 相似文献
80.
Microscale Transport and Sorting by Kinesin Molecular Motors 总被引:1,自引:0,他引:1
As biomolecular detection systems shrink in size, there is an increasing demand for systems that transport and position materials at micron- and nanoscale dimensions. Our goal is to combine cellular transport machinery-kinesin molecular motors and microtubules-with integrated optoelectronics into a hybrid biological/engineered microdevice that will bind, transport, and detect specific proteins, DNA/RNA molecules, viruses, or cells. For microscale transport, 1.5 microm deep channels were created with SU-8 photoresist on glass, kinesin motors adsorbed to the bottom of the channels, and the channel walls used to bend and redirect microtubules moving over the immobilized motors. Novel channel geometries were investigated as a means to redirect and sort microtubules moving in these channels. We show that DC and AC electric fields are sufficient to transport microtubules in solution, establishing an approach for redirecting microtubules moving in channels. Finally, we inverted the geometry to demonstrate that kinesins can transport gold nanowires along surface immobilized microtubules, providing a model for nanoscale directed assembly. 相似文献