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991.
A comparative statistical analysis of "synaptic ribbons" evolution over a 24 hour period during two different photoluminous seasons (September, and winter) is carried out. Seventy male rats were used. Statistical analysis involved the Kolmogorov-Smirnov test, variance analysis, the Student t-test and Pearson's correlation test. The results show that "synaptic ribbons" evolve during the circadian phase and through two different seasons, with a clear and marked influence of point-time (p < 0.0001) and season (p < 0.0001).  相似文献   
992.
Italy's mental health law of 1978 provided for the gradual phasing out of psychiatric hospitals (PH) and the creation of comprehensive community-based systems. However, these changes have taken place at different times and in different forms. There are now three different organizational and care models operating in Italy: in the first, common in Southern Italy, the former PH and the new general hospital general wards (GHPW) coexist; in the second, outpatient departments complement the above facilities, but the hospital activity remains central; in the third model, a community model has been given priority-the so-called community priority. While many reports have been published describing the activity of some of the services adhering to the third model, no report has been published specifically describing the activity of services which work according to the second model, such as Cremona. In this paper, the activity of the Cremona psychiatric services is described, and the consequences of the reform law and the problems related to an hospital-based activity are emphasized.  相似文献   
993.
Upon the development, divulgation and improvement of the Ambulatory Electrocardiographic Monitoring (AEM) techniques, the problem of the arrhythmias after an acute myocardial infarction (AMI) has acquired a new acuteness. Its importance becomes clearly evident from the fact today recognized that about 10% of the patients die within the first year after AMI and that the great majority of them dies suddenly. The prognostic value of certain types of ventricular arrhythmias is now well proved to be an independent risk factor respecting to the late complications of AMI, namely the sudden death issue. In this paper, after referring the prognostic criteria for the ventricular arrhythmias, the Author proposes an AEM execution calendar for the AMI patients, since the late hospital phase (hospital discharge). Afterwards, the controversial therapeutic problem of the ventricular arrhythmias is approached, quoting the pharmacological set-backs and pointing out the AEM limitations in regard to the selection and efficacy confirmation of the anti-arrhythmic drugs. At last, a few conclusions of the "Cardiac Arrhythmia Pilot Study" (CAPS, 1986) are mentioned and an other ongoing multicenter study is referred, whose conclusions will be of capital importance to define the anti-arrhythmic therapy utility in the setting of the post-AMI patients.  相似文献   
994.
A monoclonal antibody (mAb 62-3G1) to the GABAA receptor/benzodiazepine receptor/Cl- channel complex from bovine brain was used with light and electron microscopy in goldfish retina and light microscopy in chicken retina to localize GABAA receptor immunoreactivity (GABAr-IR). GABAr-IR was found in the outer plexiform layer (OPL) in both species, in three broad bands in the inner plexiform layer (IPL) of goldfish, and in seven major bands of the chicken IPL. A small percentage of amacrine cell bodies (composing at least three types) were stained in chicken. In goldfish OPL, GABAr-IR was localized intracellularly and along the plasma membrane of cone pedicles, whereas rod spherules were lightly stained, but always only intracellularly. In chicken, all three sublayers of the OPL were GABAr-IR. The presence of GABAr-IR on photoreceptor terminals is consistent with data indicating feedback from GABAergic horizontal cells to cones. In the goldfish IPL, GABAr-IR was localized to postsynaptic sites of amacrine cell synapses; intracellular staining of processes in the IPL also was observed in presumed "GABAergic" targets. A comparison of GABAr-IR with the distributions of 3H-muscimol uptake/binding, glutamate decarboxylase-IR, GABA-IR, and 3H-GABA uptake in the IPL showed either a reasonable correspondence or mismatch, depending on the marker, species, and lamina within the IPL. The distribution of GABAr-IR in the retina corresponded better with the 3H-muscimol than with 3H-benzodiazepine binding patterns yet overall was in excellent agreement with many other physiological and anatomical indicators of GABAergic function. We suggest that intracellular GABAr-IR represents the biosynthetic and/or degradative pathway of the receptor and we conclude that mAb 62-3G1 is a valid marker of GABAA receptors in these retinas and will serve as a useful probe with which to address the issue of mismatches between the localization of GABAA receptors and indicators of presynaptic GABAergic terminals.  相似文献   
995.
This review examines the role of serotonin (5-HT) in depression. Dysfunction of serotonergic neurons has been implicated as one of the causes of endogenous depression. Since serotonergic neurons innervate the hypothalamus and these neurons send collaterals to several other brain areas, it is possible that hypothalamic sites which control hormone secretion receive the same serotonergic afferents that innervate other limbic areas in the brain. Several investigators have devised neuroendocrine challenge tests measuring the effect of 5-HT agonists on plasma cortisol and prolactin in depressed patients. These tests help to identify dysfunctional 5-HT neurons, and are a "window into the brain." The secretion of cortisol and prolactin is increased predominantly by 5-HT1 receptors. However, changes in 5-HT2 receptors have also been implicated in depression. Results from our laboratory and by others suggest that brain serotonergic neurons stimulate renin and vasopressin secretion by activation of 5-HT2 receptors. Therefore, the renin and vasopressin response to 5-HT agonists should be included in neuroendocrine tests of serotonergic function in affective disorders. Since antidepressants produce a decrease in the density of 5-HT2 receptors, renin and vasopressin could be used to evaluate the antidepressant potential of new drugs.  相似文献   
996.
Labelled proteins conveyed by fast axonal transport into the sensory axons of frog sciatic nerve following axotomy have been studied by 2D gel electrophoresis. Previous work showed that in frogs acclimatized to 25 °C a cell body reaction occurs, along with regeneration of axons to their targets. In contrast, frogs acclimatized to 15 °C showed no cell body reaction and though regeneration began, it stalled after approximately 35 days. We found that axotomy at 25 °C was followed by an increase in transport of specific labelled proteins corresponding to growth-associated proteins (GAPs) identified in other regenerating systems. Surprisingly, axotomy at 15 °C also induced a similar increase, though with a slower onset, so that the highest levels of expression of GAPs occurred during the time when the axons had stalled. We conclude that sensory neurons in 15 °C frogs do detect that their axons have been injured, as shown by their ability to increase GAP synthesis. Slow and limited axonal growth is possible during a period when GAP synthesis is low compared to levels in rapidly regenerating nerves, but even when the ability to produce GAPs increases, this alone is not sufficient to sustain regeneration in the absence of other components of the cell body reaction to injury.  相似文献   
997.
Summary Animal studies have demonstrated that neuropeptides modulate nervous system functions. It has been postulated that disturbances in neuropeptide systems may be aetiological factors in psychiatric and neurological disorders. Neuropeptides related to ACTH/MSH, including ORG 2766, increase motivation and attention and facilitate recovery processes after nerve damage. These peptides may be effective during the early stage of dementia. Vasopressin and related peptides improve memory processes in animals and humans. In addition, these peptides influence social behaviour, mood and addictive behaviour. The non-opioid -type endorphins have neurolepticlike activities in animals and antipsychotic effects in a category of schizophrenic patients. Peptides related to CCK have also been found to be effective in these patients. Some neuropeptides, e.g. TRH and PLG, have been reported to exert antidepressant effects. Further research may eventually produce neuropeptides with therapeutic action in psychiatric and neurological diseases.Parts of this article were presented on the occasion of the inauguration ceremony of the Department of Psychiatry of the University of Mainz on April 2 and 3, 1987  相似文献   
998.
We have studied the effect of environmental sulfate concentration on the glycosaminoglycan synthesis of anatomically intact patellar cartilage of the mouse in vitro. Incubation of mouse patellae in medium with sulfate concentrations below 0.5 mM resulted in a diminished incorporation of sulfate but in unaltered incorporation of glucosamine. This suggested the synthesis of undersulfated glycosaminoglycans under these conditions. We characterized glycosaminoglycans synthesized at three different sulfate concentrations: a sulfate concentration physiological for the mouse (1.0 mM), a sulfate concentration in the range where sulfate incorporation was strongly diminished (0.1 mM), and an extremely low sulfate concentration (10 nM). Analysis of glycosaminoglycan disaccharides and DEAE anion chromatography of the glycosaminoglycans could not confirm the synthesis of undersulfated glycosaminoglycans at 0.1 mM. The chromatogram of glycosaminoglycans synthesized in medium containing 10 nM showed the presence of a very low sulfated glycosaminoglycan pool not observed at higher medium sulfate concentrations. Intermediately sulfated glycosaminoglycans were also synthesized during incubation with 10 nM sulfate. So, our data indicate that only very low sulfate concentrations in the medium lead to the synthesis of undersulfated glycosaminoglycans and that the sulfation mechanism of murine patellar cartilage chondrocytes does not seem to fit completely in an "all-or-nothing" pattern.  相似文献   
999.
A reduced version of the Face-Hand Test (FHT), the FHT-R, was applied to a random sample of 91 elderly subjects living in the community (S. Paulo-Brazil), to study the instrument's ability to detect Organic Brain Syndrome (OBS). The scores of the FHT-R test were then compared with a psychiatric assessment using the Clinical Interview Schedule. Five persons were regarded as OBS "cases" and 86 as OBS "non cases". At the cut-off point 0/1 the validity coefficients were as follows: Sensitivity 60%, Specificity 94%, Positive Predictive Value 38%, Negative Predictive Value 98% and Overall Misclassification Rate 8%. The usefulness of this clinical test to screen for OBS in epidemiological surveys is discussed.  相似文献   
1000.
In order to evaluate the clinical usefulness of indocyanine green video-angiography (IA), the angiographic features of choroidal neovascular membranes (CNM) were investigated in 27 eyes with choroidal neovascular diseases by means of standard fluorescein angiography (FA) and IA. FA showed the existence of CNM in 21 eyes and IA demonstrated evidence of CNM in 19 eyes, as "fan, comb or spotty hyperfluorescence" in the early stage and "leakage" in the late stage. In 6 out of 19 eyes the existence of CNM was shown by IA, while FA failed to identify the precise location and size of CNM due to the masking effect of overlying turbid fluid, massive hemorrhage or a large amount of serous fluid. The results imply that IA has an advantage over FA in cases where FA shows only the sign of occult choroidal neovascularization, and that IA can be applied to neovascular maculopathy as a routine examination.  相似文献   
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