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11.
Giovanni Savettieri Rosa Guarneri Giuseppe Salemi Vincenzo La Bella Donatella Ferraro Salvatore Scondotto Federico Piccoli 《Neurochemical research》1990,15(8):773-776
[3H]Flunitrazepam (FNZ) binding to cortical neurons from fetal rat brain was investigated in vitro. The use of a synthetic medium specific for neurons made it possible to plot a developmental curve of3H-FNZ binding in an almost pure neuronal culture. Detectable specific binding was present in vitro at time 0 (that is, the 16th gestational day). A progressive increase of binding, due to an increment in the number of recognition sites, was observed on the subsequent days. The affinity of the specific binding sites to3H-FNZ was enhanced by the addition of exogenous GABA, whereas the density was not affected. 相似文献
12.
Elvira D'Alessandro Corinna De Matteis Vaccarella Maria Luisa Lo Re Francesco Cappa Angela D'Alfonso Stefania Discepoli Maria Rosa Della Penna Giuseppe Del Porto 《Human genetics》1988,80(2):203-204
Summary Pericentric inversion of chromosome 19 has been found in several members of three unrelated families from a restricted geographical region. In one of the families, an additional pericentric inversion of chromosome 9 was observed. Reproductive problems, multiple abortions in two families and a neonatal death in the third, were present. A review of previously described cases is included, and the genetic risk connected with this type of rearrangement is also discussed. 相似文献
13.
Most growth active hormones and peptides are mitogenic only in the presence of other growth factors [e.g., Platelet Derived Growth Factor (PDGF) and Epidermal Growth Factor (EGF) in "competence-progression" fibroblast model]. We have previously described that EGF alone is able to induce the signals which appear necessary for the mitogenic stimulation of EL2 rat embryo fibroblast line. Recently, we have demonstrated that Transforming Growth Factor beta (TGF beta) slightly stimulates the mitogenic response in EL2 cells. Here, we show that in EGF-treated EL2 cells the induction of at least four inducible-secreted proteins (ISPs, range from 29,000 to 68,000 Mr) is accompanied by a marked increase in DNA synthesis. In contrast, TGF beta or different concentrations of EGF induce a slow increase of the ISPs proportional to slow induction in DNA synthesis. Our results suggest that the mitogenic response in EL2 cell line may be connected with the qualitative and quantitative induction of these secreted proteins. 相似文献
14.
Summary The effects of positive and negative ions on man and on animals have been widely studied by numerous teams of researchers.
It is well-known that negative ions have beeeficial effects on chronic and allergy-related bronchopathies in man; they stimulate
the activity of the endocrine glands and psychomotor, muscular and cerebral functions. They have a beneficial effect on general
circulation, and in particular on the microcirculatory system, such that they are suggested for use in prophylaxis and prevention
of senescence, in acute, chronic and allergy-related pneumopathies, and in neuro-vegetative dystonia. The use of artificial
negative ion producers may be a useful tool for both preventive and therapeutic purposes, as well as hygienic/domestic applications.
Systematic measurements ere taken of negative ions artificially produced in a confined space. The spatial distribution of
artificially-produced negative ions in a confined space is presented. Applications relative to artificial generators are also
suggested in order to obtain repeatable experimental conditions. 相似文献
15.
Bianca Colonna Maria Bernardini Gioacchino Micheli Francesco Maimone Mauro Nicoletti Mariassunta Casalino 《Plasmid》1988,20(3):221-231
Tn1935, a 23.5-kb transposon mediating resistance to ampicillin, kanamycin, mercury, spectinomycin, and sulfonamide was isolated from pZM3, an IncFIme virulence plasmid from Salmonella wien. Tn1935 possesses the entire sequence of Tn21 and contains two additional DNA segments of 0.95 and 2.7 kb carrying the ampicillin and kanamycin resistance genes, respectively. The latter is part of a composite element since it is flanked by two IS15-like insertion sequences (IS1936) in direct orientation. IS1936 is about 800 bp long and is closely related to IS15 delta, IS26, IS46, IS140, and IS176. Functional analysis of IS1936-mediated cointegrates shows that both insertion sequences are active and able to form cointegrates at the same frequency. Resolution of the cointegrates requires the presence of the host Rec system. The presence of the composite IS1936-element within Tn1935 supports the hypothesis that multidrug resistance transposons evolved by insertion of antibiotic determinants which are themselves transposable. 相似文献
16.
Huub J. M. Op den Camp Frank J. M. Verhagen Amelia K. Kivaisi Federico E. de Windt 《Applied microbiology and biotechnology》1988,29(4):408-412
Summary There appeared to be a clear correlation between the lignin content (% of TS) of several waste and natural materials and their degradability by rumen microorganisms. Materials with lignin contents higher than 25% were not degraded within 72 h. The effects of Kraft pine lignin and some lignin monomers on filter paper degradation, methane production and CMCase activity were tested. Testing these compounds in concentrations comparable to natural conditions showed minor effects. At higher concentrations p-coumaric acid strongly inhibited cellulose degradation and methane production in batch cultures. Influence of lignin compounds on degradation is discussed in relation to structural effects and enzyme or growth inhibition. 相似文献
17.
Distribution of polyamines and their related catabolic enzyme in etiolated and light-grown leguminosae seedlings 总被引:3,自引:0,他引:3
Diamine-oxidase (DAO; EC 1.4.3.6) activity and di-and polyamine levels were estimated along the epicotyl and root of light-grown and etiolated lentil (Lens culinaris Medicus) and pea (Pisum sativum L.) seedlings. The activity of DAO was higher in etiolated epicotyls than in lightgrown ones. In both species there was a positive correlation between DAO activity and the diamine (putrescine and cadaverine) levels along the whole epicotyl and root. Polyamine (spermine and spermidine) distribution seemed to be associated with the meristematic and elongating zone of the epicotyl and root. The physiological function of DAO is discussed in relation to its possible role in providing hydrogen peroxide to peroxidase-dependent reactions occurring in the cell wall.Abbreviations CAD
cadaverine
- DA
diamine
- DAO
diamine oxidase
- PA
polyamine
- PUT
putrescine
- SPD
spermidine
- SPM
spermine 相似文献
18.
Development of tool use in a macaque and a gorilla 总被引:3,自引:0,他引:3
Francesco Natale Patrizia Poti' Giovanna Spinozzi 《Primates; journal of primatology》1988,29(3):413-416
The development of the capacity to use a stick as a tool was tested in a macaque (Macaca fuscata) and a gorilla (Gorilla gorilla gorilla) infants that had previously shown to be able to use strings and supports as dragging tools. Subjects were tested between
15 and 38 months of age. Different levels of competence between the subjects emerged over testing. The macaque developed a
stereotyped strategy to cope with the problem, only getting random successes, whilst the gorilla developed a flexible strategy
and revealed to be able to mentally represent the solution of the problem. In fact, when not successful using the stick, the
gorilla thought out an alternative strategy, choosing and adapting a new object to use it as a tool. 相似文献
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