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221.
222.
Atanas?I.?Pavlov Milen?I.?Georgiev Mladenka?P.?IlievaEmail author 《World journal of microbiology & biotechnology》2005,21(4):389-392
The relationship between dissolved oxygen (DO) concentration, agitation rate and growth of Lavandula vera MM and rosmarinic acid biosynthesis was investigated in 3 l laboratory bioreactor. Lavandula vera MM cell suspension accumulated the highest amounts of biomass (34.8 g/l) and rosmarinic acid (1870.6 mg/l) on day 12 of cultivation at 50% dissolved oxygen and agitation speed 100 rpm and at 30% dissolved oxygen and agitation speed 300 rpm, respectively. 相似文献
223.
Pei Z Aastrup T Anderson H Ramström O 《Bioorganic & medicinal chemistry letters》2005,15(11):2707-2710
Glycosyldisulfides can interact efficiently with carbohydrate-binding entities. This has been shown for a range of thiosaccharide dimers when tested for their effects against the lectin Concanavalin A using a modified quartz crystal microbalance-technique. Contrary to the thiosaccharide monomers, showing no significant binding up to 10 mM, several of the dimers showed IC(50)-values in the low millimolar range. Three of the glycosyldisulfides tested also displayed very high positive apparent cooperativity effects that were found to be both calcium-dependent and redox-responsive. 相似文献
224.
Studies of regulatory systems in transgenic Drosophila are often compromised by possible genomic position effects on gene expression. As a result, it is desirable to be able to manipulate multiple regulatory elements in a single transgene construct. We developed an I-SceI endonuclease-based method to efficiently delete preassigned sequences from transgenes with the use of direct repeat sequences of just 126 nucleotides. This system can be used in combination with the existing cre-lox and FLP-FRT recombinational mechanisms in order to modify up to three regulatory regions in a given transgene. We validated the utility of our combination approach by demonstrating new properties of the Fab-7 insulator. 相似文献
225.
It was shown that pharmalite is an effective drug in the therapy of urolithiasis. The efficiency of pharmalite was determined from the surface tension of urine. 相似文献
226.
Previously we have described highly unstable yellow mutations induced by chimeric elements that consist of genomic sequences originating from different regions of the X chromosome flanked by identical copies of an internally deleted 1.2 kb P element. To study further the origin and the mechanism of formation of chimeric mobile elements, we analyzed complex y-sc mutations, induced by inversions between P elements located in the neighboring yellow and scute loci. The breakpoints of the inversions are flanked by two P elements in head-to-head orientation on one side and by one P element on the other side. Such an arrangement of P elements leads to frequent duplication into the site between the two P element copies located in head-to-head orientation of the yellow sequences adjacent to the single P element. The duplicated yellow sequences either partly replace the sequence of one of the P elements or are inserted between the conserved head-to-head oriented P elements. In some cases two copies of the yellow sequence are duplicated between the P elements in inverted tail-to-tail orientation. The structure of the P elements at the place of duplication and of the P element- yellow junction suggests that the described duplications, which form chimeric mobile elements, are generated through the previously proposed synthesis-dependent strand annealing mechanism. 相似文献
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229.
N Vlakhov P Georgiev G Angelov T Zheliazkova 《Biulleten' eksperimental'no? biologii i meditsiny》1985,99(1):25-26
The enzymic tests and radionuclide hepatography were used to study and compare liver function after rabbits were exposed to tetrachloromethane poisoning. The activity of serum enzymes of cholinesterase, alkaline phosphatase, aldolase and leucine aminopeptidase was determined. Hepatography was made with the use of 198Au-colloid with an activity 0.74 MBC. The enzymic tests were demonstrated to be more sensitive than radionuclide hepatography in detecting the earliest parenchymatous lesions in the liver. The data obtained correlate with the data of the pathohistological examinations, which demonstrated the presence of marked vacuole parenchymatous fatty dystrophy. The authors recommend that the enzymic tests should be used for detecting early hepatic lesions induced by tetrachloromethane. 相似文献
230.
Metabolically stable and metabolically labile DNA-like RNA 总被引:1,自引:0,他引:1