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排序方式: 共有4929条查询结果,搜索用时 15 毫秒
1.
DNA was efficiently and quantitatively isolated from extremely small quantities of mycelia (0.1–10 mg) of different phytopathogenic
moulds by grinding freeze-dried mycelia with glass beads and then using a commercial DNA extraction kit. The efficiency of
disruption of the mycelia and the quantitative DNA extraction was proved by microscopy and the quantification of isolated
DNA by real time PCR.
Presented at the 27th Mykotoxin-Workshop, Dortmund, Germany, June 13–15, 2005
Financial support: German Research Foundation (DFG grant Pr 708/2). J.M. thanks the Cusanuswerk for a doctoral scholarship 相似文献
2.
RegB is involved in the control of the phage T4 life cycle. It inactivates the phage early mRNAs when their translation is
no more required. We determined its structure and identified residues involved in substrate binding. For this, all backbone
and 90% of side-chain resonance frequencies were assigned. 相似文献
3.
The results of a detailed analysis of 100 supernumerary limbs generated by 180° ipsilateral rotation (on the same limb stump) of regeneration blastemas is presented. The limbs were analyzed in terms of their position of origin, frequency, cartilage structure by Victoria blue staining, and muscle structure by serial sections. Single, double, or triple supernumeraries can be produced at no unique position of origin, although the posterodorsal quadrant was preferred. Four classes of supernumerary limbs were generated by such operations—normal; double dorsal or double ventral; part normal/part mirror imaged; part normal/part inverted in approximately equal frequencies. After amputation of these supernumeraries the same muscle patterns are faithfully regenerated. A hypothesis to explain the production of these abnormal limbs is proposed based on the observed phenomenon of fusion of supernumerary blastemata, but their regenerative behaviour presents problems for current models of pattern formation. Similar results have been obtained with developing limb buds and the relation between development and regeneration is discussed. 相似文献
4.
Summary Adsorption isotherms for the adsorption of chromium onZoogloea ramigera are developed. The rates were affected by the pH and temperature of adsorption medium. The biomass ofZ. ramigera at pH 2.0 where the optimum pH for biosorption lies exhibited the highest chromium adsorptive uptake capacity. In general, higher adsorptive uptake was observed at 25°C than 35°C and 45°C. 相似文献
5.
Mehmet Yaar can 《American journal of physical anthropology》1989,78(1):3-8
This study analyzes and compares the dental size variation and sexual dimorphism of the Highland Beach Mound people, a late southeastern prehistoric aboriginal Florida population (ca. 800-1200 AD) with a somewhat earlier midwestern group (ca. 200-800 AD) and an Archaic sample (ca. 4160-2558 BC). The lengths and breadths of maxillary and mandibular permanent teeth of 99 individuals were measured, and crown surface areas were calculated for the molars. Results indicated that there was little sexual dimorphism. Only the mesiodistal dimensions of the upper P2 and lower C were significantly different at the P less than 0.05 level. In terms of dental size, what appears to be a chronologically based reduction in most points of comparison was seen in all three groups, with the exception of the molars, which were larger in the Highland Beach sample than in the earlier Schultz Mound. 相似文献
6.
Matthias Kirsch Mustafa B. A. Djamgoz Hans-Joachim Wagner 《Cell and tissue research》1990,260(1):123-130
Summary A negative feedback interaction between luminosity type horizonatal cells (HCs) and green-sensitive cones generates the long-wavelength-sensitive depolarizing response in biphasic chromaticity type HCs. This interaction is suppressed in the dark and is potentiated by light adaptation of the retina. HCs are morphologically plastic; during light adaptation, their dendritic terminals within cone pedicles extend, giving rise to spinules. This paper examines whether there is a quantitative correlation between the time course of light-dependent formation of the spinules and enhancement of the feedback interaction. The strength of the feedback interaction in isolated retinac of the roach was determined as the neutral wavelength at which reversal of spectral response polarity occurred in biphasic HCs. A good correlation was found between the neutral wavelength and the spinule/ribbon ratios of retinae. Biphasic HCs were intracellularly stained with horseradish peroxidase and the correlative ultrastructure of the contacted pedicles was examined. Neutral wavelength was found to be correlated with the spinule number, weighted according to the number of synaptic contacts mediating feed-forward transmission. The latter was estimated from the total number of labelled Cb/H2 HC processes (central and lateral) at synaptic triads. A model in which spinules mediate the negative feedback interaction of HCs in the retina of cyprinid fish is presented. 相似文献
7.
Mustafa Özilgen 《Applied microbiology and biotechnology》1988,29(6):536-543
Summary Large amounts of data indicated that most of the metabolic processes of the acidogenic (acid producing) and the solventogenic (solvent producing) fermentations were regulated by product accumulation. A simple unstructured model simulated microbial growth, product formation and substrate utilization in six different fermentations, where five different microorganisms produced various combinations of ten different products. Specific growth rates of these microorganisms decreased proportionally with overall product accumulation. The products were excreted in non-growth associated pattern. Excretion of some of these products were inhibited by the overall product accumulation similarly as the microbial growth. A substrate consumption model which considered the biomass and individually all the products as separate substrate sinks simulated the data satisfactorily. 相似文献
8.
A protein antigen of Mycobacterium leprae is related to a family of small heat shock proteins. 总被引:15,自引:4,他引:11 下载免费PDF全文
A H Nerland A S Mustafa D Sweetser T Godal R A Young 《Journal of bacteriology》1988,170(12):5919-5921
The gene encoding an immunologically important 18-kilodalton protein antigen of Mycobacterium leprae has been sequenced, and the amino acid sequence of the antigen has been deduced. The 18-kilodalton antigen is strikingly similar in size and sequence to a family of eucaryotic heat shock proteins. 相似文献
9.
10.
Analysis of molecular deletions with cDNA probes in patients with Duchenne and Becker muscular dystrophies 总被引:2,自引:0,他引:2
H Gilgenkrantz J Chelly M Lambert D Récan J C Barbot G J van Ommen J C Kaplan 《Genomics》1989,5(3):574-580
In the course of a systematic survey of DMD and BMD patients with intronic probes and with cDNA probes covering three-fourths of the coding sequence, 45 molecular deletions within the DMD gene were investigated. Forty-two percent of the breakpoints were located in the intronic sequence containing probe P20, whereas the other deletions were widespread around the more proximal part of the gene. Most of the BMD deletions were in the P20 region. Pulsed field gel electrophoresis was used to determine the size of some deletions and allowed us to estimate the physical distance between the intronic probes JBir and P20. The reading frame was checked in 11 cases with proximal deletions and found to be disrupted in 6 of 7 DMD patients, in 1 intermediate case, and, unexpectedly, in 3 BMD patients. 相似文献