Search results for "MDA"

Lower Ovetian (Lower Cambrian) trilobites and biostratigraphy of the Pedroche Formation (Sierra de Córdoba, southern Spain)

2005

The low Lower Cambrian rocks from the Sierra de Cordoba, which consist of well exposed mixed facies and abundant fossil assemblages showing long stratigraphic ranges throughout the Pedroche Formation, represent one of the best successions of this age in Europe. The fossil assemblages include diverse Ovetian archaeocyaths, trilobites, small shelly fossils, calcimicrobia, trace fossils and stromatolites. Trilobites are still poorly known, and thus they are the main objective of this work. The trilobites studied originate from three sections. At the Arroyo de Pedroche 1 section, cf. Bigotinella and Bigotina bivallata are replaced towards the top by Lemdadella linaresae, Lemdadella perejoni sp.…

Postsynaptic NO/cGMP Increases NMDA Receptor Currents via Hyperpolarization-Activated Cyclic Nucleotide-Gated Channels in the Hippocampus

2013

The nitric oxide (NO)/cyclic guanosine monophosphate (cGMP) signaling cascade participates in the modulation of synaptic transmission. The effects of NO are mediated by the NO-sensitive cGMP-forming guanylyl cyclases (NO-GCs), which exist in 2 isoforms with indistinguishable regulatory properties. The lack of long-term potentiation (LTP) in knock-out (KO) mice deficient in either one of the NO-GC isoforms indicates the contribution of both NO-GCs to LTP. Recently, we showed that the NO-GC1 isoform is located presynaptically in glutamatergic neurons and increases the glutamate release via hyperpolarization-activated cyclic nucleotide (HCN)-gated channels in the hippocampus. Electrophysiologi…

Nitric oxide and excitatory postsynaptic currents in immature rat sympathetic preganglionic neurons in vitro.

1997

Neuronal nitric oxide synthase immunoreactivity was localized to sympathetic preganglionic neurons of the intermediolateral cell column and cyclic GMP immunoreactivity to nerve fibers projecting into the intermediolateral cell column of 20-25-day-old rats. Whole-cell patch-clamp recordings were made from sympathetic preganglionic neurons in spinal cord slices of immature rats and the role of nitric oxide and cyclic GMP on excitatory postsynaptic currents was studied. Superfusing the slices with the nitric oxide precursor L-arginine (300 microM) increased the amplitude of evoked excitatory postsynaptic currents as well as the frequency of spontaneous miniature excitatory postsynaptic current…

Pathway-specificity in N-methyl-d-aspartate receptor-mediated synaptic inputs onto subplate neurons

2007

The subplate plays an important role in forming neuronal connections during early cortical development. We characterized by the use of whole-cell and cell-attached patch-clamp recordings in coronal brain slices from newborn mice (postnatal day [P] 0-3) the functional properties of two major pathways onto subplate neurons (SPn), the thalamocortical and the intra-subplate synaptic input. The two afferent pathways were stimulated extracellularly with bipolar electrodes placed in the thalamus and the subplate, respectively. Synaptically evoked and pharmacologically isolated N-methyl-d-aspartate receptor (NMDAR) -mediated responses with an onset latency of approximately 6 ms could be reliably re…

Neuroprotective effect of flupirtine in prion disease

2003

Apoptotic neuronal cell death is a hallmark of prion diseases. The apoptotic process in neuronal cells is thought to be caused by the scrapie prion protein, PrPSc, and can be experimentally induced by its peptide fragment, PrP106-126. This process is a target for potential drugs to combat prion disease or to ameliorate its symptoms. Flupirtine (Katadolon), a pyridine derivative that is in clinical use as a nonopioid analgesic, has a potent cytoprotective effect, at concentrations above 1 microg/mL, on neuronal cells treated with PrP(Sc) or PrP106-126. This drug acts as an N-methyl-D-aspartate (NMDA) antagonist, but does not bind to NMDA receptors. Flupirtine normalizes the level of intracel…

Latvijas lauku pašvaldības finanses: diplomdarbs

1939

4 - 5 gadu vecu bērnu izziņas interešu par dabu veidošanās pētījumdarbībā

2016

Diplomdarba pētījuma mērķis ir teorētiski un praktiski pētīt 4-5 gadus vecu bērnu izziņas interešu veidošanos par dabu pētījumdarbības procesā pirmsskolā.Teorētiskajā daļā analizēti pedagoģiski psiholoģiskie nosacījumi 4-5 gadīgu bērnu izziņas interešu par dabu veidošanās procesā, raksturota bērnu pētījumdarbība pirmsskolā un atlasītas metodes bērna izziņas interešu veidošanās sekmēšanai pētījumdarbībā. Teorētiskās analīze rezultātā izveidoti izziņas intereses par dabu 4 – 5 gadus veciem bērniem kritēriji, rādītāji un līmeņu apraksti. Praktiskajā daļā pārbaudīta atlasīto metožu efektivitāte 4 – 5 gadus vecu bērnu izziņas intereses par dabu veidošanās sekmēšanā pētījumdarbībā pirmsskolā. Sec…

Audzinātāja personības problēma modernajā audzināšanā: diplomdarbs

1939

Brīvības princips paidagoģikā: diploma darbs [Brīvības princips pedagoģijā...]

1933

Three Patterns of Oscillatory Activity Differentially Synchronize Developing Neocortical Networks In Vivo

2009

Coordinated patterns of electrical activity are important for the early development of sensory systems. The spatiotemporal dynamics of these early activity patterns and the role of the peripheral sensory input for their generation are essentially unknown. We performed extracellular multielectrode recordings in the somatosensory cortex of postnatal day 0 to 7 rats in vivo and observed three distinct patterns of synchronized oscillatory activity. (1) Spontaneous and periphery-driven spindle bursts of 1-2 s in duration and approximately 10 Hz in frequency occurred approximately every 10 s. (2) Spontaneous and sensory-driven gamma oscillations of 150-300 ms duration and 30-40 Hz in frequency oc…