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81.
82.
Quantitative receptor autoradiography was used to study possible alterations of the densities of multiple serotonin (5-HT) receptor subtypes and of serotonin transporter in the brain of 5-HT(2C) receptor knockout mice. The radioligands employed were [(3)H]citalopram, [(3)H]WAY100,635, [(3)H]8-OH-DPAT, [(3)H]GR125743, [(3)H]sumatriptan, [(3)H]MDL100,907, [(125)I](+/-)DOI, [(3)H]mesulergine, [(3)H]5-HT, [(3)H]GR113808, and [(3)H]5-CT. As expected, radioligands that label 5-HT(2C) receptors showed a complete absence of labeling in mutant mice choroid plexus and significantly reduced densities in other brain regions expressing 5-HT(2C) receptors. With the rest of the radioligands, no significant alterations in the densities of labeled sites were found in any brain region. In situ hybridization showed no changes in 5-HT(2A) receptor and serotonin transporter mRNA levels, whereas 5-HT(2C) receptor mRNA levels were reduced in certain brain regions. The present results indicate that the mouse serotonergic system does not exhibit compensatory up- or down-regulation of the majority of its components (serotonin transporter and most 5-HT receptor subtypes) in response to the absence of 5-HT(2C) receptors.  相似文献   
83.
There are several indications that central nervous system (CNS) lesions in visna are immune-mediated and that cell-mediated immunity (CMI) may be of importance in the initiation of the lesions. To study the role of CMI in the pathogenesis of CNS lesions, five sheep were infected by intracerebral inoculation with visna virus and observed for 1 year. The following parameters were monitored at regular intervals: (1) neutralizing and ELISA antibodies; (2) visna virus-specific stimulation of lymphocytes from peripheral blood; (3) lymphocyte subpopulations in peripheral blood, cerebrospinal fluid (CSF) and brain at sacrifice. The CNS lesions were graded and compared with other parameters. The time course and titers of antibodies did not correlate with the severity of CNS lesions whereas the CMI did, indicating that CMI may play an important role in lesion development. The correlation of the number of CD8-positive cells in the CSF with the severity of lesions and the reversed ratio of CD4/CD8-positive cells in the diffusely infiltrated neuroparenchyma indicates that the CD8-positive T lymphocyte may be an important effector cell in the induction of CNS lesions.  相似文献   
84.
Subchronic administration of cocaine induces behavioral sensitization (increasing hypermotility) to a challenge dose of the drug administered 72 h after the cessation of treatment. The effects of repeated administration of the neurohypophyseal hormones oxytocin (OXT) and arginine8-vasopressin (AVP) on the development of behavioral sensitization induced by subchronic treatment with cocaine were investigated in mice. Repeated treatment of OXT and AVP did not modify the locomotor stimulatory effect of the challenge dose of cocaine in cocaine-naive control animals. OXT in a dose of 0.5 microgram (sc) augmented the cocaine-induced behavioral sensitization. In contrast, AVP (0.005-0.5 microgram/mouse, sc) dose dependently attenuated the development of sensitization to the hypermotility-inducing effect of cocaine. The results suggest that the behavioral sensitization induced by cocaine can be modulated in opposite directions by neurohypophyseal hormones.  相似文献   
85.
The authors' aim was to evaluate the range of uroflowmetry in diagnostics of stress urinary incontinence (sui) in women. The examinations were carried out in 59 women with sui, aged from 35 to 45 years (group I). The control group consisted of 20 asymptomatic women (group II). To evaluate volumes of urine voided during micturition in a unit of time a urological flowmeter UF-1 (produced by COTM, Bia?ystok) was used. Numeric data of flow were analysed, as well as registered curves of flow were ascribed to one of the following flow patterns: normal, multi-peak or interrupted. The conducted studies revealed statistically significant differences in flow values in group I, compared to group II. A more frequent incidence of multi-peak and interrupted flow patterns was found in women with sui, which could be related to a neurogenic component in etiology of the disease.  相似文献   
86.
87.
This study was performed to examine the pattern of Superoxide (O 2 ·) generation from leukocytes using the O 2 · specific chemiluminescence (CL) method.Cypridina luciferin analog, 2-methyl-6-(p-methoxyphenyl)-3,7-dihydroimidazo[1,2-alpha]pyrazin-3-one (MCLA) was used as a CL probe. The appropriate conditions of the MCLA method was first determined for the evaluation of the time course of O 2 · generation by leukocytes. The time course of O 2 · generation obtained by the MCLA-CL system was compared with that by the luminol-dependent CL, electron spin resonance (ESR)/spin trapping, and cytochromec systems. Following stimulation by three different stimulants (PMA, OZ, FMLP), leukocytes continuously generated O 2 · for up to 5 h in the MCLA-CL system, irrespective of the kind of stimulation. The curves obtained by generation ceased more rapidly in the luminol-CL, ESR/spin trapping, and cytochromec systems. A 50% activity of the initial value was observed at 70 min in the MCLA-CL system, but 30, 10 and 35 min in the other systems, respectively. The CL or O 2 · generation value decreased to less than 1% (possible termination) at 300, 90, 120 and 180 min, respectively. With the exception of ESR studies with OZ, the cell viability was not significantly affected in any of the trials. These results indicate that leukocytes can generate O 2 · much longer than previously estimated and that the MCLA-CL-system is the most suitable system for the measurement of the O 2 · generation by leukocytes.  相似文献   
88.
89.
The advantages and limitations of the slowing down of epithermal neutrons and the thermal neutron reflection methods were compared for bulk hydrogen analysis. In both cases, the same sample dimensions were used, i.e. 10cm diameter and 8cm height. It was found that the sensitivity of the slowing down method is higher by a factor of approximately 20 in average and the matrix effect can be neglected as compared to the neutron reflection technique. The simultaneous application of the two methods renders the determination of the H content and the C/H atomic ratio possible. The effect of spatial distribution of hydrogen in the matrix to be investigated on the number of reflected neutrons was also studied.  相似文献   
90.
Neurodevelopmental treatment (NDT) is the most used rehabilitation approach in the treatment of patients with stroke in the Western world today, despite the lack of evidence for its efficacy. The aim of this study was to conduct an intervention check and measure the nurses' competence, in positioning stroke patients according to the NDT approach. The sample consisted of 144 nurses in six neurological wards who were observed while positioning stroke patients according to the NDT approach. The nurses' combined mean competence scores within the wards was 195 (70%) of 280 (100%) possible, and for each ward the mean score varied between 181 (65%) and 206 (74%). This study indicates that nurses working in hospitals where the NDT approach has been implemented have the knowledge and skills to provide NDT nursing.  相似文献   
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