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71.
72.
A method to immobilize fungal hyphae onto the wells of 96-well microplates for use in an in-direct ELISA to screen for antifungal antibodies in sera and cell culture supernatants is described. The hyphae from three genera (Penicillium, Eurotium andFusarium) were successfully attached by overnight drying onto wells precoated with poly-L-lysine and glutaraldehyde. Microscopy revealed that the hyphae remained attached to the wells throughout the ELISA and antiserum titrations showed that the attached hyphae were uniformly coated and remained reactive. Background absorbances were low and the plates could be stored at –20 °C without loss of reactivity. 相似文献
73.
Serological differentiation of acute and chronic schistosomiasis using Schistosoma mansoni recombinant protein RP26 总被引:1,自引:0,他引:1
We obtained a recombinant protein encoded by Schistosoma mansoni gene which was able to differentiate acute from chronic schistosomiasis when applied as antigen in enzyme-linked immunosorbent assay (ELISA). A cDNA clone encoding a 26 kDa recombinant protein (RP26) was selected by screening of an adult worm S. mansoni λZAP expression library with rabbit sera produced against PIII, an adult worm protein fraction already known to possess protective and immunomodulating effects. The clone cDNA presented 99% identity with S. mansoni Sm22.3 gene. We assayed IgG reactivity of sera from 18 patients with acute, 25 patients with chronic S. mansoni infection and 20 uninfected donors with RP26 in ELISA. Our results showed that 89% of sera were positive in acute schistosomiasis group, and only 26% in chronic group, without false-positive reactions in uninfected group. In mice the immune response to RP26 increased up to week 9 after infection and then diminished. We proposed that production of antibodies binding to RP26 stopped at the chronic stage of disease. The testing of sera from eight other parasitic infections with RP26 revealed no positive reactions in majority of sera. However, we observed low positive reaction in sera from 20% of leishmaniasis patients. Our results indicate that a recombinant protein RP26 can be used as immunodiagnostic reagent for detection of acute phase of schistosomiasis mansoni. 相似文献
74.
研究了污染沉积物泥浆液、固两相五氯酚(PCP)厌氧生物降解.结果表明,投加10g·kg-1厌氧颗粒污泥,经31d处理泥浆液、固两相PCP降解率达98.9%,平均降解速率达到80mg·kg-1·d-1,对照处理平均降解速率仅为4.4mg·kg-1·d-1,颗粒污泥生物强化作用明显.作为泥浆修复过程的调控因子,有机溶剂、共基质和表面活性剂对PCP降解效应不同,投加乙醇,可提高PCP解吸和降解速率,4d内两相PCP降解速率达到54.3mg·kg-1·d-1;而投加共基质和非离子表面活性剂乙二醇丁醚后,液、固两相PCP降解均出现迟滞,两者均不同程度地抑制PCP降解. 相似文献
75.
Bohong Liao Lingrong Peng Jin Zhou Huiting Mo Jialan Zhao Zike Yang Xiaowen Guo Peiquan Zhang Xin Zhang Zhibo Zhu 《化学与生物多样性》2019,16(5)
Human nasopharyngeal carcinoma is a common head and neck malignancy with high incidence in Southeast Asia and Southern China. It is necessary to develop safe, effective and inexpensive anticancer agents to improve the therapeutics of patients with nasopharyngeal carcinoma. A series of small molecular compounds based on 6‐(pyrimidin‐4‐yl)‐1H‐indazole were synthesized and evaluated for antiproliferative activities against human nasopharyngeal carcinoma cell lines SUNE1. Compounds 6b , 6c , 6e and 6l showed potent antiproliferative activities similar to positive control drug cisplatin in vitro with lower nephrotoxicity than it. N‐[4‐(1H‐Indazol‐6‐yl)pyrimidin‐2‐yl]benzene‐1,3‐diamine ( 6l ) was selected for further study. It was found that 6l induced mitochondria‐mediated apoptosis and G2/M phase arrest in SUNE1 cells. Furthermore, compound 6l at 10 mg/kg can suppress the growth of an implanted SUNE1 xenograft with a TGI% (tumor growth inhibition) value of 50 % and did not cause serious side effects in BALB/c nude mice. This study suggests that 6‐(pyrimidin‐4‐yl)‐1H‐indazole derivatives are a series of small molecule compounds with anti‐nasopharyngeal carcinoma activities. 相似文献
76.
蛋白质序列特性的研究对于蛋白质的结构及功能具有重要意义。该文为了研究蛋白质序列是否具有混沌行为,先将蛋白质序列通过氨基酸电子离子相互作用势(electron interaction potential,EIIP)转化为时间序列,再根据混沌理论对其进行相空间重构,利用去偏自相关系数,经典G-P算法确定系统的时间延迟t和嵌入维数m,系统的最大Lyapunov指数则用改进的最大Lyapunov指数计算方法计算,其结果绝大多数为正,从而确认了蛋白质时间序列的混沌行为,并对特例进行了说明。 相似文献
77.
78.
The use of isochronal reference standards in phase and modulation fluorescence lifetime measurements
Errors in phase and modulation lifetime measurements observed with the only commercially available instrument are readily apparent when the Debye-Sears modulation tank is not perfectly tuned. Unfortunately, we have found that exact tuning was extremely difficult to achieve and maintain. We report that these errors could be reduced by using single-lifetime (homogeneous) reference standards whose fluorescence lifetime approximated that of the unknown sample (isochronal standards). A number of useful standards are suggested. In the proposed method, the phase shift and relative modulation of the sample emission are measured using the isochronal standard as a reference to determine the effective characteristics of the sinusoidal excitation. The importance of the improvement in accuracy accomplished by the proposed methods is illustrated by the accurate resolution of fluorescence lifetime heterogeneity for two known heterogeneous samples. 相似文献
79.
I. J. Mackay J. P. Gibson 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1993,87(1-2):152-160
Selection reduces additive genetic variation by generating gametic-phase disequilibrium, a phenomenon largely ignored when predicting response in plant breeding programs. The development of gametic-phase disequilibrium is here taken into account when predicting the response to selection for various schemes of recurrent selection applicable to plant populations. A general program permits prediction of response to selection from schemes of recurrent selection in which two or more rounds of selection occur in each cycle. An example from Sugar Beet, with alternate rounds of half-sib and S1 family selection, is illustrated. It is shown that failure to take into account the effects of gametic-phase disequilibrium can result in substantial overestimation of the response to selection as well as to changes in rank of the merits of alternative breeding schemes. For a given scheme, ignoring gametic-phase disequilibrium has only small effects on defining the optimum allocation of plots and the numbers of families tested. 相似文献
80.
Bruno Hoste Lieve Luyten Ilse Claeys Elke Clynen Mazibur M. Rahman Arnold De Loof Michael Breuer 《Entomologia Experimentalis et Applicata》2002,104(2-3):281-288
In order to unravel the physiological, endocrine, and behavioral differences between gregarious and solitarious forms of the desert locust, Schistocerca gregaria (Forsk.) (Orthoptera, Acrididae), a constant supply of rather large numbers of solitary individuals has to be guaranteed. This represents a bottleneck, mainly because of the intensity of the labor involved and limited laboratory accommodation. The method we describe here substantially reduces the space and manpower needed. The survival rate we obtained in the solitarised population was relatively high, reaching about 55%. The optimal rearing temperature proved to be 32–36 °C. Cabbage leaves and oat flakes sufficed for feeding all year round. Special racks have been designed that enable high density stacking and easy handling. The solitarisation process was monitored over ten consecutive generations. Changes in morphometrics, eye stripes, color, and behavior were recorded, of which only morphometrics, temperature related development, and mortality are discussed. A shift towards the solitarious phase was recorded, with clear differences between gregarious, 1st generation and 7th to 10th generation solitarious locusts. 相似文献