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41.
Lidija Simova Carolyn Williams Georgi D. Efremov Aleksandra Gordova-Muratovska Stojka Suštić Eila K. Watson Robert Williamson 《Human genetics》1990,85(4):432-433
Summary Chromosomes from 19 unrelated Southern Yugoslav families in which cystic fibrosis (CF) occurs were analysed for the presence
of the ΔF508 mutation, using polymerase chain reaction amplification followed by dot blot and polyacrylamide gel analysis.
Of the 38 CF chromosomes, 15 (39.5%) carry the ΔF508 deletion. Restriction fragment length polymorphism haplotypes for KM19/PstI, XV2c/TaqI and J3.11/PstI marker loci were determined and are compared for a total of 34 N and 37 CF chromosomes. 相似文献
42.
Synopsis Evidence is presented which suggests that the nonparasitic lamprey, Lampetra (Eudontomyzon) gracilis Kux, 1965, is conspecific with the parasitic lamprey Eudontomyzon danfordi Regan, 1911. The diagnostic characters of the holotype and of the non-type material of E. gracilis are features found in E. danfordi specimens in their second and final year of adult life, thereby making the former a junior synonym of the latter. 相似文献
43.
Summary Immobilization of Escherichia alcalescens cells into genu-carrageenan gel for L-aspartic acid production was studied with respect to the optimized preparation of heterogenous biocatalyst /2.5–3.0% genu-carrageenan, 15% biomass, 50–55 °C, tannin added/. 相似文献
44.
Elizabeta Pertot Damjana Rozman Stjepan Miličić Helena Sočič 《Applied microbiology and biotechnology》1988,28(2):209-213
Summary The morphological development ofClaviceps paspali immobilized in Ca-alginate gel was examined. During consecutive reincubations, the immobilized mycelia differentiated into swollen, arthrosporoid-like cells, which never appeared during fermentation of free mycelium. Such differentiation could be connected with the improved, prologed vitality and metabolic activity of the immobilized cells. 相似文献
45.
Miroslav Flieger Jaroslav Votruba Vladimír Křen Sylvie Pažoutová Viktor Rylko Přemysl Sajdl Zdeněk Reháček 《Applied microbiology and biotechnology》1988,29(2-3):181-185
Summary Kinetic parameters of production of clavine alkaloids were evaluated in twoClaviceps purpurea strains. Mutagenesis brought about enhanced resistance of the biosynthetic system towards alkaloids. Addition of glucose into the fermentation medium altered the zero order kinetics of production to activation-inhibition kinetics. The glucose treatment allowed performance of both elymoclavine-inhibitionless and clavine alkaloid-decompositionless fermentations if a combination of fermentation and separation units in a closed loop was used.Nomenlacture
k
1
rate constant of agroclavine synthesis (mg Agro · mg Elymo/l·g DW·day for stage 1, mg Agro/g DW·day for stage 2)
-
k
2
parameter describing inhibition of agroclavine formation rate by elymoclavine (mg Elymo/l)
-
k
3
specific rate of agroclavine decay (l/g DW·day)
-
k
4
maximal specific rate of elymoclavine synthesis (stage 1, 1/g DW·day, stage 2, mg Elymo/g DW·day)
-
k
4
–
maximal specific rate of elymoclavine synthesis in stage 1 (inhibition-activation mechanism) (mg Elymo/g DW·day)
-
k
5
physiological constant describing the elymoclavine decay rate (l2/g DW·day·mg Elymo)
-
k
5
–
physiological constant describing the activation of elymoclavine biosynthesis by elymoclavine (mg Elymo/l)
-
k
6
physiological constant describing the repression of elymoclavine biosynthesis by elymoclavine (mg Elymo/l)
-
k
7
maximal specific growth rate (1/day)
-
k
8
specific rate of biomass decay (l/g DW·day)
-
A
agroclavine concentration (mg/l)
-
E
elymoclavine concentration (mg/l)
-
r
A
specific rate of agroclavine biosynthesis (mg Agro/g DW·day)
-
r
E
specific rate of elymoclavine biosynthesis (mg Elymo/g DW·day)
-
r
i
specific rate of alkaloid biosynthesis (mg alkaloid/g DW·day)
-
X
dry biomass concentration (g/l)
-
specific growth rate (1/day)
Abbreviations Agro
agroclavine
- Elymo
elymoclavine
- Chano
chanoclavine
- DW
dry weight of biomass 相似文献
46.
J. Šťovíčková J. Turková B. Urbánek V. Bažant J. Kavalírová 《Biotechnology Techniques》1988,2(2):121-126
Summary The effect was studied of the method of drying chymotrypsin attached to bead cellulose on its chemical and physical characteristics. These characteristics are not deteriorated when replacing the commonly used lyophilisation by fluid drying in the air stream. The preparations saved essentially the same proteolytic activity as well as stability even when increasing the drying air temperature to 70°C. 相似文献
47.
48.
František Krahulec 《Folia Geobotanica》1988,23(2):173-179
The present paper gives comments on the nomenclature of associations ofNardetalia andNardo-Caricion rigidae from Central Europe. A brief list of important homonyms and ambiguous names is added. 相似文献
49.
L. Kádasi J. Gécz J. Matúšek T. Krivušová V. Ferák M. Devoto J. Hruškovič G. Romeo 《Human genetics》1992,89(3):305-306
Summary Analysis of a sample of 50 unrelated cystic fibrosis (CF) patients and 46 nuclear families from Slovakia (Czechoslovakia) by the polymerase chain reaction and Southern hybridization revealed that the proportion of the F508 mutation was 58% in this population, and that the frequency of the B (i.e., KM19/XV2c [1–2]) haplotype was increased in both F508 and nonF508 CF chromosomes (98% and 46%, respectively). These results support the view that the trans-European gradient of the F508 frequency is of a geographical rather than of an ethnic origin, and that in Slavonic populations, there exists an as yet unidentified but frequent CF mutation other than F508, associated with the B haplotype. 相似文献
50.
Zbyněk Roček 《Pal?ontologische Zeitschrift》1991,65(3-4):351-361
Three-dimensionally preserved and chemically prepared skulls and natural casts of representatives of the families Benthosuchidae, Melosauridae, and Capitosauridae yield data on the structure of the ethmoidal endocranium, i. e. of those nasal cranial structures that consisted originally of cartilage. This study demonstrates that the ethmoidal endocranium was principally a dorsoventrally compressed plate, pierced by a broad and oblique canal which communicated anteriorly with the outer dorsal surface by the fenestra endonarina and posteriorly with the mouth cavity by the fenestra endochoanalis(seu foris). The canal was very short, and housed the olfactory organ. The ethmoidal endocranium was connected with the palatoquadrate by the commissura quadratocranialis anterior; there was no lateral ethmoidal commissure, however, in older individuals the anterior section of the palatoquadrate might also contact the postchoanal part of the nasal endocranial skeleton. 相似文献