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11.
Pirjo Rajaniemi‐Wacklin Anne Rantala Maria. A. Mugnai Silvia Turicchia Stefano Ventura Jarka Komrkov Liisa Lepist Kaarina Sivonen 《Journal of phycology》2006,42(1):226-232
In this study, the first reported isolates of the genera Snowella and Woronichinia were characterized by 16S rRNA gene sequencing and morphological analysis. Phylogenetic studies and sequences for these genera were not available previously. By botanical criteria, the five isolated strains were identified as Snowella litoralis (Häyrén) Komárek et Hindák Snowella rosea (Snow) Elenkin and Woronichinia naegeliana (Unger) Elenkin. This study underlines the identification of freshly isolated cultures, since the Snowella strains lost the colony structure and were not identifiable after extended laboratory cultivation. In the 16S rRNA gene analysis, the Snowella strains formed a monophyletic cluster, which was most closely related to the Woronichinia strain. Thus, our results show that the morphology of the genera Snowella and Woronichinia was in congruence with their phylogeny, and their phylogeny seems to support the traditional botanical classification of these genera. Furthermore, the genera Snowella and Woronichinia occurred commonly and might occasionally be the most abundant cyanobacterial taxa in mainly oligotrophic and mesotrophic Finnish lakes. Woronichinia occurred frequently and also formed blooms in eutrophic Czech reservoirs. 相似文献
12.
B Porcelli M Pizzichini A Di Stefano R Leoncini A Taddeo E Marinello 《Bollettino della Società italiana di biologia sperimentale》1989,65(12):1201-1205
The behavior of plasma and urine oxypurines (hypoxanthine and xanthine) and of uric acid has been studied in normal subjects and in gout patients. Oxypurines and uric acid were increased in the plasma of gout patients but only the urinary excretion of hypoxanthine was higher in this group. The interpretation of the observed variations is discussed. 相似文献
13.
A Tabucchi L Terzuoli A Di Stefano M Pizzichini R Leoncini E Dispensa E Marinello 《Bollettino della Società italiana di biologia sperimentale》1989,65(11):1097-1103
Phosphoribosyl-1-pyrophosphate (PRPP) amidotransferase is the "key anabolic enzyme" of purine nucleotide synthesis; PRPP synthetase connects the pentose cycle with the same pathway. We have studied their behavior in 5 control subjects and in 8 affected by CLL. Determination of PRPP amidotransferase was carried out through the evaluation of 14C-glutamic acid (released by 14C-glutamine) in the incubation mixture. PRPP synthetase was followed by adding ATP and ribose 5-phosphate to the incubation mixtures, and by evaluating the PRPP formed through the release of CO2 in a coupled reaction. In the case of PRPP-amidotransferase, our values are in the range reported in the literature: in patients affected by CLL, the enzyme activity is much higher and the increase is more evident when values referred to the patients, than when to the cells. Our values of PRPP synthetase are consistent with those of Peters and Veerkamp, but no definite conclusion is possible in the case of leukemic patients. 相似文献
14.
Valerio Vidotto Giuseppe Picerno Stefano Caramello Giovanna Paniate 《Mycopathologia》1988,104(3):129-135
The passage between the yeast and mycelial forms of Candida albicans B 311-10 was studied by using the minimal syntehtic medium of Shepherd et al. [19] modified without biotin and with low glucose concentrations. It was observed that biotin, aminoacids and particularly pH are not important factors in the dimorphism of C. albicans. The only factor of notable importance in the passage of yeast form to mycelial form in C. albicans was glucose concentration. 相似文献
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Summary pSE211 fromSaccharopolyspora erythraea integrates site-specifically into the chromosome through conservative recombination betweenattP andattB, the plasmid and chromosomal attachment sites. Integration depends on the presence ofint, an open reading frame (ORF) that lies adjacent toattP and encodes the putative integrase. Immediately upstream ofint liesxis (formerly calledorf2) which encodes a basic protein that is thought to exhibit DNA binding.xis andint were cloned in various combinations in pUC18 and expressed constitutively inEscherichia coli from thelac promoter.attP andattB were cloned inStreptomyces orE. coli plasmids containing kanamycin resistance (KmR) or chloramphenicol resistance (CmR) markers. Stable KmR CmR cointegrates formed byattP ×attB orattP ×attP recombination (integration) were obtained inE. coli hosts that expressedint. Co-integrates were not found in hosts expressingint+xis. Excision (intraplasmidatt site recombination) was examined by constructing plasmids carryingattL andattR or twoattP sites separating CmR from KmR and by following segregation of the markers in various hosts. BothattL ×attR andattP ×attP excision depended on bothxis andint inE. coli. pSE211att site integration and excision were not affected by a deletion inhimA, the gene encoding a subunit of integration host factor. 相似文献
18.
B Corman A di Stefano M Wittner G Geelen 《Comptes rendus des séances de la Société de biologie et de ses filiales》1991,185(3):143-155
In the course of aging, the renal concentrating ability is markedly reduced. This defect may result from an inappropriate synthesis of antidiuretic hormone in the central nervous system or may be due to an impaired renal response to vasopressin. The two hypotheses have been studied in vivo in rats and in vitro in mice. The results of these studies indicated that: 1) dehydration induces a comparable release of vasopressin along the hypothalamo-hypophysial axis in 10, 20 and 30 month-old rats; 2) there is no change with age of the number of nephrons, single nephron filtration rate or transport capacity of Henle's loop of cortical nephrons which could account for an impaired renal response to vasopressin; 3) the reduced concentrating ability of the kidney appears to be linked to a decreased response of the medullary thick ascending limb of Henle's loop which in part is responsible for the cortico-papillary gradient of solutes within the kidney. 相似文献
19.
Rita Baraldi Francesca Fasolo Fabbri Malavasi Stefano Predieri Marco Castagneto 《Plant Cell, Tissue and Organ Culture》1991,24(3):187-191
The effects of humic substances on in vitro culture of Golden Delicious apple are reported. Potassium humate (KH) when used in proliferation showed a negative interaction with BA while it enhanced rooting when IBA was not present in the culture medium. In the presence of IBA, KH increased root number and reduced root growth. The highest concentration tested, 500 mg l-1, caused a drastic reduction in root system development. 50 mg l-1 KH hastened rooting and plants grew more rapidly when transferred to soil. 相似文献
20.
Nucleid acid metabolism in the LAM of the rat, both before and after castration, and during testosterone treatment, was investigated. RNA synthesis was increased by testosterone treatment, to varying degree, in adult and in prepubertal castrated rats, and was not merely dependent on the degree of hypertrophy of the LAM. The DNA content and the incorporation rate of formate-14C into DNA showed a characteristic profile under the same conditions: the atrophy of LAM following castration and its subsequent restoration appeared to be accompanied by variations in nuclei number. The possible role of testosterone in DNA duplication and in cell mitosis is hypothesized here; further investigation must be integrated by careful morphometric observation. 相似文献