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991.
An investigation of the occurrence of multiple sclerosis (MS) was undertaken in the City of Galion, Ohio, USA, because of a report of an increased number of cases. As of June 1, 1987, there were 18 living cases of MS in Galion and Polk Township, for a prevalence rate of 112 cases per 100,000 population. The expected rate is approximately 65-170 cases per 100,000. In a case-control study, residents of Galion or Polk Township who had MS were compared to residents who did not have MS. The controls were matched to the cases on age and sex and had lived in Galion for at least as long as their matched case. The cases and controls did not differ in the distribution of their present or past Galion addresses, occupational histories or workplace exposures. Cases were more likely to have graduated from high school and college than controls. Cases were more likely than controls to report a history of allergies, to recall two or more relatives who had neurologic diseases that began before their first MS symptoms, to report owning a cat that died of unexplained causes and to recall having received oral polio vaccine. Cases and controls had similar levels of antibodies to measles, chickenpox, cytomegalovirus and the human T-cell lymphotrophic virus I. 相似文献
992.
Dopamine differentially regulates dynorphin, substance P, and enkephalin expression in striatal neurons: in situ hybridization histochemical analysis. 总被引:14,自引:0,他引:14
Dopamine regulation of the levels of dynorphin, enkephalin, and substance P messenger RNAs in rat striatal neurons was analyzed with in situ hybridization histochemistry (ISHH). Relative levels of peptide mRNA expression in the patch and matrix compartments of the dorsolateral striatum were compared among control rats, rats treated for 10 d with apomorphine, rats with unilateral 6-hydroxydopamine (6-OHDA) lesions of the nigrostriatal dopaminergic system, and rats with nigrostriatal dopaminergic lesions followed 2 weeks later by 10 d of apomorphine treatment. Image analysis of ISHH labeling demonstrated that the number of neurons expressing each peptide mRNA remained constant, whereas the relative level of peptide mRNA per neuron changed significantly, depending on the experimental treatment. Dynorphin mRNA expression increased following chronic apomorphine treatment: striatal patch neurons increased to an average of 100% above control values, whereas striatal matrix neurons showed only a 25% increase. Dynorphin mRNA expression decreased following 6-OHDA lesions: patch neurons showed an average 75% reduction in expression, whereas matrix neurons showed no significant change. In animals with 6-OHDA lesions followed by apomorphine treatment, both patch and matrix neurons showed an average increase in dynorphin expression of 300% above control levels. Changes in dynorphin mRNA levels with these treatments were matched by qualitative changes in dynorphin immunoreactivity both in the striatum and in striatonigral terminals in the substantia nigra. Neither substance P nor enkephalin mRNA levels showed a significant difference between the striatal patch and matrix compartments in any experimental condition (in the dorsolateral striatum). Substance P mRNA expression was increased an average of 50% after 10 d of apomorphine treatment and showed an average decrease of 75% following 6-OHDA lesions of the mesostriatal system. There was no significant change in the expression of substance P mRNA in striatal neurons compared to control values in rats with combined 6-OHDA lesion and apomorphine treatment. Enkephalin mRNA expression was not significantly altered by chronic apomorphine treatment but showed an average increase per cell of some 130% above control levels following 6-OHDA-induced lesions of the mesostriatal system. In animals with a 6-OHDA lesion and apomorphine treatment, enkephalin mRNA was also elevated but not significantly above the levels produced by the lesions alone. These data show that the expression of dynorphin, enkephalin, and substance P is differentially regulated by the mesostriatal dopaminergic system and, further, suggests that the mechanisms by which this regulation occurs may be different for the 3 peptide families. 相似文献
993.
994.
R J Katz 《Neuroscience and biobehavioral reviews》1991,15(3):375-381
Intrusive thoughts and images, often of a violent, horrific, or blasphemous nature are the hallmark of Obsessive Compulsive Disorder (OCD). OCD patients frequently also often have reductions in normal serotonergic (5-HT) function. This paper proposes a model of 5-HT function involving the routine filtering and suppression of violent or libidinal impulses. This model accounts for OCD as an instance of failed inhibition. The model also appears to resemble Freud's model of ego-id interactions at least in part, suggesting that it may be possible to psychobiologically substantiate a Freudian metaphor. 相似文献
995.
R Feder 《The Journal of clinical psychiatry》1991,52(4):163-164
Three male patients are described in whom anorgasmia developed during treatment with fluoxetine for depression. During attempts to treat the anorgasmia with cyproheptadine, all three patients suffered a relapse of depressive symptoms. The possible mechanism of this effect is discussed in relation to serotonergic systems. 相似文献
996.
Transneuronal degeneration of thalamic neurons following partial deafferentation was studied using [3H]thymidine autoradiography. Timed-pregnant female Sprague-Dawley rats received systemic injections of [3H]thymidine on embryonic day (E) 13, 14 and/or 15. On the day of birth, pups were anesthetized by hypothermia and subjected to unilateral enucleation, unilateral removal of the inferior colliculus or sham lesion. Animals were sacrificed on postnatal day 10 or 30 and the brains processed for autoradiography. Material from sham-lesioned animals demonstrates that neurons destined for the dorsal lateral geniculate nucleus (LGd) undergo final mitoses on E13, 14 and 15. Neurons in the ventral medial geniculate nucleus (MGv) undergo final mitoses on E13 and 14. Thirty days following neonatal unilateral eye removal, the contralateral LGd displays a loss of approximately 30-35% of [3H]thymidine labeled neurons. Neonatal unilateral removal of the inferior colliculus results in a loss of approximately 30-40% of labeled neurons in MGv. For both LGd and MGv, shorter survival times reveal less severe cell loss. Late generated (E15) LGd neurons show less severe loss following enucleation than do earlier generated neurons. These results document the degree of cell loss in sensory thalamic nuclei following deafferentation and demonstrate that [3H]thymidine autoradiography provides a useful quantitative method for assessing anterograde transneuronal cell loss in targeted populations of neurons in the developing central nervous system. 相似文献
997.
998.
Total gastrectomy is discussed as the operation of choice among different surgical approaches for gastric carcinoma. We prefer the performance of an elective total gastrectomy with systematic lymphadenectomy (compartments I and II) and obligatory splenectomy. A retrospective study of 1,704 consecutive cases of gastric carcinomas showed a better outcome following total gastrectomy in relationship to distal subtotal gastrectomy, but these results cannot be used as evidence because of the lack of a prospective study. Nevertheless, a precise analysis of our cases in regard to tumor site and tumor type could show a frequency of only 6% to maximally 30%, in which elective total gastrectomy may represent a procedure too extensive to justify for an oncological course. 相似文献
999.
1000.