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41.
42.
Kirsty E Amos Shahram Anari Charlotte A Buswell Emma J McNeill Athanasia Printza Stephen J Ray Isam Rustom 《Annals of general psychiatry》2006,5(1):1-5
Background
The aim of the current study is to investigate the relationship between physical anhedonia and psychopathological parameters, pharmacological parameters or motor side-effects in a sample of inpatients with schizophrenia in an acute episode of their illness. 相似文献43.
Parvalbumin 3 is an Abundant Ca2+ Buffer in Hair Cells 总被引:3,自引:0,他引:3
Stefan Heller Andrea M. Bell Charlotte S. Denis Yong Choe A.J. Hudspeth 《Journal of the Association for Research in Otolaryngology》2002,3(4):488-498
Ca2+ signaling serves distinct purposes in different parts of a hair cell. The Ca2+ concentration in stereocilia regulates
adaptation and, through rapid transduction-channel reclosure, underlies amplification of mechanical signals. In presynaptic
active zones, Ca2+ mediates the exocytotic release of afferent neurotransmitter. At efferent synapses, Ca2+ activates the
K+ channels that dominate the inhibitory postsynaptic potential. A copious supply of diffusible protein buffer isolates the
three signals by restricting the spread of free Ca2+ and limiting the duration of its action. Using cDNA subtraction and a
gene expression assay based on in situ hybridization, we detected abundant expression of mRNAs encoding the Ca2+ buffer parvalbumin
3 in bullfrog saccular and chicken cochlear hair cells. We cloned cDNAs encoding this protein from the corresponding inner-ear
libraries and raised antisera against recombinant bullfrog parvalbumin 3. Immunohistochemical labeling indicated that parvalbumin
3 is a prominent Ca2+-binding protein in the compact, cylindrical hair cells of the bullfrog's sacculus, and occurs as well
in the narrow, peanut-shaped hair cells of that organ. Using quantitative Western blot analysis, we ascertained that the concentration
of parvalbumin 3 in saccular hair cells is approximately 3 mM. Parvalbumin 3 is therefore a significant mobile Ca2+ buffer,
and perhaps the dominant buffer, in many types of hair cell. Moreover, parvalbumin 3 provides an early marker for developing
hair cells in the frog, chicken, and zebrafish. 相似文献
44.
45.
L H Anderson T L McDonald G M Thiele L W Klassen 《Journal of clinical laboratory analysis》1992,6(3):113-118
Different assay systems have been used to quantitate lymphokine-induced natural cytotoxic activity as a measure of immune status. This study compares the effects of inducing cytotoxicity in a bulk culture system, where effector cells are transferred to a micro culture well for assay, to a micro culture system where the effector cells are not transferred. The effector/target ratio for both the bulk and micro culture systems was calculated using the number of viable effector cells present at the time of target cell addition. After overnight incubation with interleukin-2 (IL-2), the lytic activity of murine spleen cells to targets using a micro culture system was increased two-fold over the bulk culture method. This increase was amplified further after 5 days of activation with IL-2, in that the micro culture system resulted in a four-fold increase in cytotoxic activity. The loss of some adherent cells in the bulk culture system did not explain the overall decrease in recovered cytotoxicity. The difference appeared to be related to cell loss during centrifugation. Therefore, the E/T ratios are different in the two systems if not corrected for the number of viable cells. 相似文献
46.
47.
Enhanced stimulus-reward learning by intra-amygdala administration of a D3 dopamine receptor agonist
The amygdala is considered to be a critical neural substrate underlying the formation of stimulus-reward associations, and
is known to receive substantial innervation from dopaminergic neurons located within the ventral mesencephalon. However, relat-
ively little is known about the function of the mesoamygdaloid dopamine projection in stimulus-reward learning. Recently,
we have found post-session intra-amygdala microinjections of d-amphetamine to enhance appetitive Pavlovian conditioning as assessed in a discriminative approach task. In the present study,
we have examined the effects of dopamine receptor agonists possessing relative selectivity for the D1, D2 and D3 receptor subtypes in order to examine more fully the role of the mesoamygdaloid dopamine projection in stimulus-reward learning.
Thus, subjects were trained to associate an initially neutral stimulus (CS+) with 10% sucrose reward (US). A second, control stimulus (CS−) was also presented but never paired with sucrose reward. In order to measure specifically the conditioned response to CS+/CS− presentation, responding during CS and US presentations was measured separately. Immediately following each training session,
subjects received bilateral intra-amygdala infusion of 0.1, 1 or 10 nmol/side of SKF-38393, quinpirole or 7-OH-DPAT. Infusions
of SKF-38393 or quinpirole were without effect on CS+ approach. However, post-session intra-amygdala infusions of 7-OH-DPAT enhanced selectively CS+ approach in a dose-dependent fashion. No dose of any drug affected CS−approach, US behaviours, or measures of extraneous behaviour. Subsequent acquisition of a novel conditioned instrumental response
was also unaffected. Thus, the present data indicate a selective involvement of the D3 dopamine receptor subtype in the modulation of stimulus-reward learning by the mesoamygdaloid dopamine projection.
Received: 12 December 1996 / Final version: 9 April 1997 相似文献
48.
Meningeal hemangiopericytoma of the posterior fossa and thoracic spinal epidural space: case report.
The rare combination of spinal and intracranial meningeal hemangiopericytomas in the same patient is reported. The coexistence of cerebral and spinal meningiomas of all histological subtypes is distinctly uncommon with only nine cases found in the literature. 相似文献
49.
Sidestream versus mainstream carbon dioxide analyzers 总被引:1,自引:0,他引:1
50.