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61.
Marina V. Lavrentieva Mark I. Rivkin Alexander G. Shilov Marina L. Kobetz Igor B. Rogozin Oleg L. Serov 《Mammalian genome》1991,1(3):165-170
In analysis of the repeats from the mink X Chromosome (Chr), we have identified a B2-like repetitive sequence of 195 base pairs (bp) flanked by short direct repeats of 14 bp. It contains regions homologous to the split intragenic RNA polymerase III promoter and a 3 A-rich region followed by an oligo(dA) sequence. A feature of the repeat is the presence of a perfect polypyrimidine tract 22 bp in length absent from the known Alu- and Alu-like sequences. Alignment of the mink B2-like sequence and mouse B2-consensus sequence allowed us to estimate their similarity as 55%. The repeat is present in 1–2×105 copies per mink genome and 2–4×103 copies per X Chr. In situ hybridization analysis demonstrated a similar distribution pattern of the B2-like repeat along the length of all the mink chromosomes including the X. We also observed the presence of mink B2-like hybridizable sequence in the genomes of other Carnivora species.The nucleotide sequence data reported in this paper have been submitted to EMBL Data Library and have been assigned the accession number X52381 (MVB2RPT). 相似文献
62.
63.
Marina Bandeira Marc-André Bouchard Luc Granger 《Applied psychophysiology and biofeedback》1982,7(3):317-330
This paper discusses the general methodological controversy between individual and group research approaches by comparing the main characteristics of these two methods as applied to the specific context of basic research on voluntary heart rate control. A review of the literature published over the past 19 years in this area of study shows an imbalance in the frequency of utilization of these two methods that strongly favors short-term group designs. Implications of this research tendency are discussed. The relevance and the advantages of applying the individual approach to voluntary autonomic control research are outlined. This area is particularly amenable to the individual approach because the phenomena under study seem to be characterized by, among other things, a smaller intrasubject than intersubject variability. It is suggested that the present imbalanced tendency in the choice of a research method be corrected and that researchers adopt a more flexible attitude in the choice of the best method for studying each specific problem. 相似文献
64.
Summary We describe a reciprocal translocation (10;13) in a man, ascertained through the study of meiosis in semen, and a partial trisomy 10q in his abnormal son. The phenotypic anomalies of the partial 10q trisomy syndrome are probably due to the presence in triplicate of the region q25qter of chromosome 10. 相似文献
65.
A biological method was used in addition to the chemical methods of identification in the screening programme of new antibiotics. The method consists of evaluation of the effect of the crude antibiotic preparations on microbial forms resistant to various antibiotics. The efficiency of the biological method is shown. It provides more complete and rapid characterization of the properties of the new antibiotics and their rough identification at early screening stages. 相似文献
66.
E A Dyskin T M Mefodovskaia M L Moiseeva L P Tikhonova 《Arkhiv anatomii, gistologii i émbriologii》1976,71(11):105-108
The method of detection of lactate dehydrogenase with some modification was used to study the microcirculatory bed in total preparations of serous membranes and plane sections of organs of any square surface. The employment of non-fixed material, the short time (from 15 to 60 min) necessary to obtain preparations of any size and simultaneous determination of the localization and the degree of the activity of the enzyme--are, to the authors opinion, undoubtful advantages of the given method, which can be an addition to the well-known impregnation method of determination of the microcirculatory bed. 相似文献
67.
Nitrate, ammonia, urea, and glycine were compared as nitrogen sources for Acetabularia mediterranea. Cells grew normally in media containing nitrate or urea, while cells did not grow at all when the same amount of N was supplied as ammonium ion. The utilization of glycine remains questionable. Cells in medium without added N (NDM) increased in length and some formed reproductive caps. The whorls of vegetative cells showed considerable hypertrophy in NDM and in glycine. This hypertrophy was due to the elongation of only the first-(a1) and second- (a2) order articles. When cut, the basal portion of cells without added N regenerated new apices with whorls. The development of these whorls was inversely proportional to the NO2 concentration. Analyses showed that the intracellular nitrogen pool in young cells and regenerating bases was very small, about 1/10 of that of fully grown cells. Therefore we suggest that trace amounts of N contaminants in the medium supported growth and development, the uptake of which was facilitated by the hypertrophied whorls, under N-limited conditions. 相似文献
68.
We have previously reported that treatment of CsA with aqueous HCl gives rise to the formation of a number of water-soluble compounds. Two of these were identified from their FAB-MS/MS spectra as open-chain nona- and decapeptides. We describe here the identification of two other main compounds deriving from the same treatment. Identification was rendered possible from the comparison of their FAB-MS/MS spectra with those of methyl and acetyl derivatives. The two compounds are water-soluble, open-chain undecapeptides corresponding to 1,11 seco-CsA and of 4,5 seco-isoCsA, respectively. 相似文献
69.
Aleksandra Topic Marina Milenkovic Snezana Uskokovic-Markovic Dragana Vucicevic 《Biological trace element research》2010,134(3):296-306
Investigations of effective, orally active, and safe antidiabetic metallopharmaceuticals have been carried out during the
last two decades. It has been reported that tungsten compounds mimic the action of insulin in intact cell systems. As insulin
mimetics, the most investigated tungsten compound was sodium tungstate (ST), rarely investigated was tungstophosphoric acid
(WPA), but never alanine complex of tungstophosphoric acid (WPA-A). In this study, the insulin mimetic activity of three different
tungsten compounds, ST, WPA, and WPA-A, was evaluated by means of in vitro measurements of the glucose uptake and inhibition
of free fatty acids release from epinephrine-treated isolated rat white adipocytes. We investigated the influence of concentration
(lower and higher, 0.1 and 1.0 mM, respectively) and solvent: isotonic salt solution—saline (0.9% w/v of NaCl) and dimethyl sulfoxide (DMSO; 2% v/v), on the biological effect of tested compounds. Our experimental data showed that all of the three investigated tungsten
compounds possess insulin mimetic activity in vitro on the isolated adipocytes. Influence of concentration and solvents on
insulin mimetic effect for the certain tungsten compounds were: WPA was shown effect independently of concentration and solvents;
higher concentration and DMSO were significant decreasing insulin mimetic effect of ST; lower concentration and saline led
to decreasing effect of WPA-A. Generally, there were no differences in insulin mimetic effect of three tungsten compounds
in lower concentration and dissolved in DMSO. When saline was used as solvent, it was needed higher concentration of investigated
compounds to accomplish the same effect. In conclusion, our results suggest that low concentration (0.1 mM) of ST, WPA, and
WPA-A dissolved in 2% DMSO could be the good candidates for in vivo investigation of their antidiabetic properties. 相似文献
70.
The paratabulate calcareous cyst of Calciodinellum operosum Deflandre was recorded in a sediment trap sample collected in the Bay of Naples (Tyrrhenian Sea, Italy). The germination of this resting stage produced a phototrophic vegetative cell that had the typical plate pattern of a Scrippsiella species. The cyst morphotypes, observed in a clonal culture of this species, ranged from cysts with well-developed paratabulation to cysts in which the paratabulation was barely visible, to cysts covered by irregularly shaped crystals. The analysis of thin sections of the calcareous cysts using the polarized light microscope equipped with crossed nicols and a gypsum plate showed that the optical orientation of the calcite crystals was tangential in all the morphotypes examined. We suggest that the crystallographic method we describe might provide insights for calcareous cyst taxonomy and phylogeny . 相似文献