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91.
The drug rifampin, when added at the time of infection, inhibits synthesis of the phage Qbeta. Both viral ribonucleic acids and viral proteins are made in nearly the same amount as in the absence of rifampin, but the rate of assembly into phage particles is low. 相似文献
92.
Jadwiga Molé-Bajer 《Chromosoma》1967,22(4):465-480
The influence of chloral hydrate on endosperm cells of Haemanthus katherinae was studied. Four types of mitotic disturbances were described: a) Normal bipolar mitosis with one or few chromosomes lying out of the metaphase plate. Bipolar mitoses are sometimes arrested in anaphase and followed by the formation of a restitution nucleus. b) Tri — or multipolar anaphases. c) Diffuse anaphase movements i.e., active anaphase movements without distinct poles followed by the formation of multipolar phragmoplasts and cell walls. d) C-mitosis resembling the effect of colchicine. Some aspects of the described phenomena were discussed. 相似文献
93.
It was shown that Botrytis cinerea, an isolate infecting apples, secreted in vivo and in culture a variety of glycosidic hydrolases with substrate specificity towards the polysaccharides of cell walls. The following enzymes were partially separated by column chromatography on DEAE-Sepharose CL-6B: two cellulases, three xylanases, one arabinanase, polygalacturonase, β-glucosidase, β-xylosidase, β-galactosidase, β-mannosidase and α-galactosidase. The activity of glycosidic hydrolases tested was strongly inactivated by NBS and weaker by PCMB, tetranitromethan, dibromoacetophenon and Fe3+, The results indicate synergistic action of the obtained cellulase, xylanase, polygalacturonase and arabinanase in apple cell wall degradation. 相似文献
94.
Edyta Kostrzewa-Susow Jadwiga Dmochowska-Gadysz Jan Oszmiaski 《Journal of Molecular Catalysis .B, Enzymatic》2007,49(1-4):113-117
As a result of microbial transformation of baicalin and baicalein the products of 4′-hydroxylation of the B ring, O-methylation at C-6, and both O-methylation at C-6 and hydroxylation at C-4′ were obtained. Transformations of baicalin were accompanied by the reaction of hydrolysis. 相似文献
95.
P Sacha J Jaworowska D Ojdana P Wieczorek S Czaban E Tryniszewska 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2012,50(2):322-324
The aim of this study was to investigate the prevalence of the aacA4 gene in a population of multidrug resistant strains of P. aeruginosa isolated from bronchial secretions obtained from the Intensive Therapy Unit (ITU). Twelve MDR isolates were tested for antibiotic susceptibility and the presence of the aacA4 gene. In this study, 58.3% of the strains contained (6')-Ib' aminoglycoside acetyltransferase gene. All of the studied strains (aacA4-positive and aacA4-negative) were susceptible only to colistine (100%). Among other antibiotics, the lowest resistance rates were those shown against ceftazidime (14.3% to 20%) and imipenem (28.6% to 40%). Our studies frequently revealed the presence of the aacA4 gene as a factor responsible for resistance; it is probable that other mechanisms of resistance to aminoglycoside antibiotics also occurred. 相似文献
96.
97.
Aleksandra Rusin Agnieszka Gogler Magdalena Głowala-Kosińska Daria Bochenek Aleksandra Gruca Grzegorz Grynkiewicz Jadwiga Zawisza Wiesław Szeja Zdzisław Krawczyk 《Bioorganic & medicinal chemistry letters》2009,19(17):4939-4943
Genistein, due to its recognized chemopreventive and antitumor potential, is a molecule of interest as a lead compound in drug design. While multiple molecular targets for genistein have been identified, so far neither for this isoflavonoid nor for its natural or synthetic derivatives disruption of microtubules and mitotic spindles has been reported. Here we describe such properties of the synthetic glycosidic derivative of genistein significantly more cytotoxic than genistein, 7-O-(2,3,4,6-tetra-O-acetyl-β-d-galactopyranosyl)-(1→4)-(6-O-acetyl-hex-2-ene-α-d-erythro-pyranosyl)genistein, shortly named G21. We found that G21 causes significant mitotic delay, frequent appearance of multipolar spindles, and alteration of the interphase microtubule array. 相似文献
98.
99.
Jadwiga Ostrowska-Czubenko Magdalena Gierszewska-Drużyńska 《Carbohydrate polymers》2009,77(3):590-598
The polyion complex membrane (PEC) composed of chitosan (Ch) and sodium alginate (NaAlg) designated for the separation of water/organic mixtures by pervaporation and/or direct methanol fuel cell technology was synthesized and analysed by FTIR, DSC, DTG and X-ray diffraction. The polyion complex formation between Ch (cationic polyelectrolyte) and NaAlg (anionic polyelectrolyte) was confirmed by Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TG) and differential scanning calorimetry (DSC). The state of water in pure polyelectrolytes (PE) and PEC was studied by DSC. Results show that freezable and non-freezable water exist in analysed Ch, NaAlg and Ch/NaAlg hydrogels, while there are variations in the amount of non-freezing bound water in PE/water and PEC/water systems. Both ionic crosslinking as well as physical structure influence the state of water, and especially the non-freezable water content, in ionic hydrogel membranes. 相似文献
100.
The aim of the study was to assess salivary fluoride concentrations and ingestion of fluorides after five different techniques
of topical fluoride treatment. Ten volunteers received applications of fluoride gel, toothpaste, and foam. Fluoride concentrations
were determined using ion-selective fluoride electrode in the samples of unstimulated saliva before and after procedures.
The amounts of fluoride applied, recovered from the mouth, and retained in the mouth were calculated for each treatment. It
was proved that fluoride ingestion following tray application of fluoride foam was significantly lower than ingestion following
tray applications of fluoride gel (p < 0.01). The use of limited amounts of fluorides on a tray resulted in similar fluoride retention and lower ingestion comparing
to the method which involves a large portion of fluorides followed by rinsing. Tooth brushing resulted in high salivary retention
rates per amount of fluorides used in the procedure. These data provide initial concept about the possible advantages of some
methods of topical fluoride application over others. 相似文献