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91.
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93.
吖啶橙失活处理应用于不对称融合初步探讨 总被引:1,自引:0,他引:1
马铃薯栽培种和野生种叶肉原生质体经过吖啶橙(AO)处理后,暗培养两天,再光照4h而失活.失活程度取决于AO处理时间、AO浓度、光照时机等.四倍体失活浓度高于二倍体,处理后马上光照失活效果最强烈,8d后光照其小细胞团同未光照处理相差不大。AO失活的栽培种NO7同罗丹明6G(R6G)失活的Solanumbulbocastanum融合后可以发生代谢互补恢复分裂,已得到假定的杂种小愈伤组织. 相似文献
94.
The effects of cold treatment on the cortical microtubules (MTs) of Chaetomorpha moniligera Kjellman were investigated by immunofluorescence microscopy. Cortical MTs in Chaetomorpha thallus are arranged longitudinally. In this study, 70–75% of MTs disassembled within 4 h on ice while the others remained stable under these conditions. Reticulate background immunofluorescence, assumed to indicate the presence of a tubulin monomer, was distributed about the stable MTs. Immunofluorescence was prominent in only 50% of the cells. Tubulin polymerization was noted where the background and MT immunofluorescence was strong. New MTs grew transversely as single strings or clusters from the sides of MTs after cold treatment for 4 h and elongated with time to take on a reticulate form at 24 h. The significance of this tubulin polymerization under cold treatment is discussed.Abbreviations MT
microtubule
- MTOC
microtubule-organizing center 相似文献
95.
The interaction of chlorpromazine (CPZ) with artificial membranes (egg-yolk phosphatidylcholine liposomes) has been studied. Measurements of the surface electric potential, which is modified in the presence of the ionized form of the drug, were obtained by electron paramagnetic resonance spectroscopy (EPR) using a positively charged amphiphilic spin-probe. This probe partitions between the aqueous and lipidic phases depending on the surface potential and on the structural state of the membrane. The surface potential was measured as a function of drug concentration in the range where the spectral line-shapes are not affected by the incorporation of the drug. From these experimental results and through an appropriate formalism we obtain information on the binding of the drug to the lipid bilayer and on the ionization of the drug in the lipidic phase.
Correspondence to: C. Anteneodo 相似文献
96.
Tijhuis L Huisman JL Hekkelman HD van Loosdrecht MC Heijnen JJ 《Biotechnology and bioengineering》1995,47(5):585-595
For a stable and reliable operation of a BAS-reactor a high, active biomass concentration is required with mainly biofilm-covered carriers. The effect of reactor conditions on the formation of nitrifying biofilms in BAS-reactors was investigated in this article. A start-up strategy to obtain predominantly biofilm-covered carriers, based on the balancing of detachment and a biomass production per carrier surface area, proved tp be very successful. The amount of biomass and the fraction of covered carrier were high and development of nitrification activity was fast, leading to a volumetric conversion of 5 kg(N) . m(-3) . d(-1) at a hydraulic retention time of 1h. A 1-week, continuous inoculation with suspended purely nitrifying microorganisms resulted in a swift start-up compared with batch addition of a small number of biofilms with some nitrification activity. The development of nitrifying biofilms was very similar to the formation of heterotrophic biofilms. In contrast to heterotrophic bio-films, the diameter of nitrifying biofilms increased during start-up. The detachment rate from nitrifying biofilms decreased with lower concentrations of bare carrier, in a fashion comparable with heterotrophic biofilms, but the nitrifying biofilms were much more robust and resistant. Standard diffusion theory combined with reaction kinetics are capable of predicting the activity and conversion of biofilms on small suspended particles. (c) 1995 John Wiley & Sons Inc. 相似文献
97.
Effects of fungal pretreatment and steam explosion pretreatment on enzymatic saccharification of plant biomass 总被引:3,自引:0,他引:3
Sawada T Nakamura Y Kobayashi F Kuwahara M Watanabe T 《Biotechnology and bioengineering》1995,48(6):719-724
The effects of consecutive treatments by a lignin-degrading fungus Phanerochaete chrysosporium and by steam explosion for the enzymatic saccharification of plant biomass were studied experimentally, and the optimal operational conditions for obtaining the maximum saccharification were evaluated. Beech wood-meal was treated by the fungus for 98 days and then by high steam temperatures of 170-230 degrees C with steaming times of 0-10 min. The treatment of the wood-meal by fungus prior to steam explosion enhanced the saccharification of wood-meal. The treated wood-meal was separated into holo-cellulose, water soluble material, methanol soluble lignin, and Klason lignin. The saccharification decreased linearly with the increase in the amount of Klason lignin. It was estimated by the equation for the saccharification of exploded wood-meal expressed as a function of steam temperature and steaming time that the maximum saccharification of wood-meal was obtained by consecutive treatments such as fungal treatment for 28 days and then steam explosion at a steam temperature of 215 degrees C and a steaming time of 6.5 min. (c) 1995 John Wiley & Sons, Inc. 相似文献
98.
Alkaline borohydride treatment is widely used for the release of carbohydrate moieties from O-glycosylated glycoproteins and mucins. We have adapted this procedure to micro quantities of glycoproteins blotted on membranes. After electrophoresis and transfer to nitrocellulose, nylon or polyvinylidene difluoride membrane, alkaline borohydride treatment was done directly on glycoprotein containing areas of membrane which were cut out with the aid of guide strips stained with Coomassie Blue or lectin-digoxigenin. In combination with standard saccharide fractionation techniques, this procedure can be used to characterize the oligosaccharides of mucins or mucin-type glycoproteins that are separated by gel electrophoresis from crude sources. Using this approach we have characterized the saccharides derived from the two species of epitectin, a malignancy-associated mucin type glycoprotein, isolated from metabolically labelled H.Ep2 cells. 相似文献
99.
Edouard Nice Bruno Catimel Martin Lackmann Steven Stacker Andrew Runting Andrew Wilks Nicos Nicola Antony Burgess 《Letters in Peptide Science》1997,4(2):107-120
The isolation of related genes with evolutionary conserved motifs by the application ofpolymerase chain reaction-based molecular biology techniques, or from database searchingstrategies, has facilitated the identification of new members of protein families. Many of theseprotein molecules will be involved in protein–protein interactions (e.g. growth factors,receptors, adhesion molecules), since such interactions are intrinsic to virtually every cellularprocess. However, the precise biological function and specific binding partners of these novelproteins are frequently unknown, hence they are known as orphan molecules.Complementary technologies are required for the identification of the specific ligands orreceptors for these and other orphan proteins (e.g., antibodies raised against crude biologicalextracts or whole cells). We describe herein several alternative strategies for the identification,purification and characterisation of orphan peptide and protein molecules, specifically thesynergistic use of micropreparative HPLC and biosensor techniques. 相似文献
100.
KOLOTKIN, RONETTE L, SUSAN HEAD, ALAN BROOKHART. Construct validity of the Impact of Weight on Quality of Life questionnaire. The Impact of Weight on Quality of Life questionnaire (IWQOL) is a 74-item self-report, condition-specific instrument that (1) assesses the effect of weight on quality of life in eight key areas, and (2) may be used as a treatment outcome measure and/or an evaluation tool for healthcare policy makers and third-party payers. This study explores IWQOL construct validity and provides new information on internal consistency, treatment effects, and differences between men and women. IWQOL total scores correlated highly with other measures of overall quality of life, and subscale scores correlated well with counterparts in the assessment battery. Internal consistency estimates for the IWQOL scales generally were high. For the women, 4-week participants, and the total sample, pretreatment-posttreatment differences were significant for all IWQOL scales and total score. For men, treatment differences were significant for the total score and all subscales except for Work and Mobility. Treatment differences for 2-week participants were significant for all scales except for Work. Consistent with previous IWQOL study results, the Comfort With Food scale scores reflected more discomfort at posttreatment as compared with pretreatment. The IWQOL, already translated into French and Italian, currently is demonstrating clinical and research utility as a quality-of-life outcome measure for clinical trials of antiobesity drugs and surgical treatments for patients with obesity. 相似文献