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81.
Lignocellulose biotransformation with immobilized cellulase,d-glucose oxidase and fungal peroxidases
Three enzymes, cellulase [see 1,4-(1,3;1,4)-β-d-glucan 4-glucanohydrolase, EC 3.2.1.4], d-glucose oxidase (β-d-glucose: oxygen 1-oxidoreductase, EC 1.1.3.4) and peroxidase (donor:hydrogen peroxide oxidoreductase, EC 1.11.1.7) immobilized on glass beads, have been incubated with lignocellulose. Fungal peroxidases from Trametes versicolor and Inonotus radiatus when mixed with cellulase and d-glucose oxidase were able to liberate phenolic compounds and d-glucose from lignocellulose. Three lignin monomers were identified. When the immobilized enzymes were incubated individually with lignocellulose they did not degrade lignin. 相似文献
82.
Barbara Siemieniako Ewa M. Rakowicz-Szulczyńska Antoni Horst 《Molecular and cellular biochemistry》1985,65(2):131-141
Non-histone chromatin proteins synthesized during chicken embryonic liver development were labeled with [3H]tryptophan and [3H]methionine and characterized by electrophoresis. During embryonic development protein/DNA ratio in chromatin was low (1.30-1.62) but synthesis of non-histone protein was high. Especially one characteristic fraction K (MW 18 000), tightly bound with DNA was preferentially associated with DNAase II sensitive, active transcribed sequences. In 7-day old and adult chicken synthesis of all non-histone proteins was low, fraction K was absent or synthesized only in small amounts in association with non-active sequences, however protein/DNA ratio in chromatin was high (2.30-2.33). 相似文献
83.
J Uchmański 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》1985,310(1142):1-75
The basic and simplest system that one can consider in ecology is a group of individuals of equal age and representing one species, that is, a cohort. This paper is an attempt to show that analysis of such a system may be of great importance to understanding basic ecological problems, such as, intraspecific competition and the dynamics of a single population. It is easy to observe that in even-aged populations individuals differ in weights. A close look can show that weight distributions in even-aged populations may have different skewness. Most common are distributions with coefficients of skewness greater than zero. Sometimes weight distributions are symmetrical or with skewness coefficients less than zero. In a cohort of growing individuals the coefficient of skewness changes with time: most often starting from zero (symmetrical distribution), it increases in time; sometimes after an initial increase it can decrease in the final stage of growth, which is related to an increased mortality of individuals. The rate of change in skewness, and the skewness itself depend on the density of individuals in a cohort and on food conditions. They are greater at higher densities and increase with deteriorating food conditions. Weight distributions are symmetrical at low densities and optimal food conditions. The differences in individual weights measured by variance of weight distributions or coefficient of variation follow the same pattern, but observed changes with time, density and food conditions are not so clear. These conclusions rest upon the review of numerous papers concerning both plants and animals, which is presented in this paper. In the past, the properties of weight distributions in even-aged populations were explained not by interactions between individuals, but rather as a natural outcome of the growth process of non-interacting individuals. The exponential equation of growth, with relative growth rate having a normal distribution in populations, was used to support this hypothesis. Obtained weight distributions were of positive skewness; however, this model, which in fact is able to describe the growth process only in its initial stage, cannot explain the changes of skewness of weight distributions with density and food conditions. A model has been developed which includes competitive interactions among members of even-aged populations to explain observed properties of weight distributions in them. The basic assumption is that intraspecific competition leads to uneven partitioning of resources, which are the object of competition. Functions describing resource partitioning among individuals are included into the model.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
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A fluorometric methods is described for determination of cardiac and urinary 3-methoxytyramine, a metabolite of dopamine. Methoxy metabolites were isolated on Amberlite CG-50 resin and oxidation to emitter form was performed with K3Fe(CN)6. Good specificity and sensitivity of determination, and a high recovery of 3-MT were obtained. 相似文献
88.
A. Wiercińska 《International Journal of Anthropology》1986,1(3):277-280
The traditional cranioscopic traits possess undoubted taxonomic value in interpreting interpopulational relationships. However,
there is a lack of studies on the correlations between particular traits. In order to fill this gap, the following set of
4 traits was analysed by use of the multiple stachastic correlations method of Wanke: 1. prominence of maxilla, 2. lower margin
of nasal aperture, 3. depth of canine fossa and 4. depth of maxillary incisure. These traits were examined by use of the photographic
scales of Michalski within the series of 104 crania from a local population of Wislica, Poland, dated to the Early Medieval
Period. The significant associations appeared in the combinations 1–2, 1–3, 3–4, 1–2–3, 1–2–4, 1–3–4, 2–3–4 and 1–2–3–4. After
removal of all the possible interactions, still significant associations remained in 1–2–4, 2–3–4, and 1–3–4. Moreover, the
places of significant surpluses appeared in the extreme places, i.e. those characterising the Europoid and Mongoloid crania. 相似文献
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