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11.
Ivo Šafařík 《Journal of industrial microbiology & biotechnology》1988,3(4):259-261
Summary A new insoluble chromogenic substrate for the determination of proteolytic activity was developed. This substrate was prepared by incorporating black drawing ink into casein and heating this complex at 200°C for 4 h. It is especially suitable for determining the activity of alkaline bacterial proteinases. 相似文献
12.
In submerged Claviceps cultures the activity of hydroxymethylglutaryl-CoA reductase preceded the increase of alkaloid production and of sterol content. During the first alkaloid phase, cell mevalonate was involved in the biosynthesis of both alkaloids and steroids. In the second production phase, it was predominantly used for alkaloid synthesis. Hydroxymethylglutaryl-CoA reductase appears to be a suitable target for physiological manipulation to increase clavine alkaloid yields. 相似文献
13.
Mathematical modelling of the course of the immune response is undoubtedly one of the most progressive and most promising areas of modern immunology. Mathematical models (along with computer programs) can be taken as "the only means of thoroughly testing and examining a large and intricate theory" (Partridge et al. 1984). The first phase of construction of mathematical models is the formulation of assumptions based on the knowledge of the facts to be modelled (manifested usually in a scheme of the presumed course of the modelled process). The first mathematical models of immune response were based on the hypothesis of a two-stage differentiation of cells participating in the humoral response, published in Prague 23 years ago (Sercarz and Coons 1962; Sterzl 1962) and illustrated by the X----Y----Z scheme. Many contemporary mathematical models still stem from this scheme which undoubtedly fits the fundamental data concerning the immune system. 相似文献
14.
15.
Plate numbers of bacteria and relative incidence of strains capable of mineralization of 2,4-dichlorophenoxyacetic acid (2,4-D)
in chernozem samples incubated for 14 d with the herbicide (50 ppm) in the presence or absence of glucose (1000 ppm) were
compared. Whereas the total number of bacteria increased 1.2-fold in the variant with 2,4-D and 2.4-fold in the variant with
glucose and the herbicide, the number of 2,4-D-mineralizing bacteria increased 12.1-fold and 34.2-fold, respectively. In a
collection of 96 isolates of soil bacteria substantially more strains capable of degradation of 2,4-D in the presence of glucose
were detected as compared with the variant without it, indicating that processes of cometabolic type are involved during the
degradation of this herbicide in the soil. 相似文献
16.
17.
Eva Klozová Jiřina Švachulová J. Smartt E. Hadač Věra Turková Véra Hadačová 《Biologia Plantarum》1983,25(4):266-273
The seed protein patterns of 12Arachis species were compared by polyacrylamide gel electrophoresis (PAGE), similarities between patterns were measured by the Jaccard
index. Results obtained confirm the close relationships established between members of the genus on morphological grounds
and support the more recent classification schemes.A. villosa andA. correntina could well be regarded as distinct species on grounds of protein differences whileA. macedoi andA. villosulicarpa (although members of the same section, Extranervosae) show considerable differentiation of their protein patterns. Surprisingly,
the formA. ×batizogaea showed less similarity in protein pattern to those of its parental species than might have been expected. The principle value
of seed protein pattern data appears to be in distinguishing species within sections. 相似文献
18.
Differential tolerance ofArabidopsis thaliana crown gall tumors and calli to 5-bromo-2′-deoxyuridine
M. Ondřej 《Biologia Plantarum》1983,25(5):391-393
The degree of tolerance of two crown gall tumors and leaf calli ofArabidopsis thaliana to BUdR was compared. The nopaline producing teratoma tumor tolerated BUdR in concentration as high as 2.10?4 M. The tolerance of octopine producing unorganized crown gall tumor to BUdR was lower, but both exceeded significantly the degree of tolerance to BUdR of untransformedA. thaliana calli, where 10?5 M BUdR already show some inhibitory effect on the growth rate. 相似文献
19.
Jana Pospíšilová Jiřina Slavíkovà J. Tupý Ingrid Tiohá T. Gichner 《Biologia Plantarum》1983,25(3):237-240
20.
Jiří Ponert 《Folia Geobotanica》1972,7(3):309-312
From the Caspian coastal region of Iran a new taxon,Sparganium erectum L. subsp.mazanderanicum Ponert, is described and illustrated. This new subspecies in some of its characters is near toSparganium erectum L. subsp.microcarpum (Neumann)Domin (with its east distribution trend); in other characters it is near toSparganium erectum L. subsp.neglectum (Beeby)Schinz etThell. (with ist south distribution trend). A comparative table of diacritical characters of these three subspecies is appended. 相似文献