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Brain morphology in first-episode schizophrenic-like psychotic patients: a quantitative magnetic resonance imaging study 总被引:5,自引:0,他引:5
L E DeLisi A L Hoff J E Schwartz G W Shields S N Halthore S M Gupta F A Henn A K Anand 《Neuropsychopharmacology》1991,29(2):159-175
Brain morphology was examined using magnetic resonance imaging in 30 first-episode patients with a schizophreniclike psychosis, 15 chronic schizophrenics, and 20 neurological controls. Statistical analyses of computer-generated measurements of regions of interest were controlled for gender, age, social class, and total brain volume. Lateral ventricular size was increased in both first-episode and chronic schizophrenic patients, with greater significance on the left than on the right side. Only the chronic patients, however, had reduced temporal lobe size, which also was greater on the left side. No major correlations of regional brain morphological measurements with cognitive functioning were found, although some measurements of verbal memory were correlated with parahippocampal size. This is a report of a preliminary study that suggests that some morphological brain changes may be present at the time of first treatment for a psychotic illness, whereas others may occur later in the course of illness. Future prospective studies may determine the clinical significance of these changes and whether they progress with the development of illness chronicity. 相似文献
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N-Nitrosodibutylamine (NDBA) and its omega-oxidized metabolites N-nitrosobutyl-4-hydroxybutylamine (4-OH-NDBA) and N-nitrosobutyl-3-carboxypropylamine (BCPN) are potent urinary bladder carcinogens. To study putative organ specific activation of BCPN, its alpha-oxidation by liver and urinary bladder microsomal fractions was investigated in comparison to NDBA and 4-OH-NDBA. Additionally, induction of DNA single strand breaks (SSB) was monitored in hepatocytes and in a human lymphoblastoid cell line (Namalva) in the presence and absence of external metabolic activation, including N-nitroso-t-butyl-n-butylamine as a negative control. BCPN was alpha-hydroxylated and dealkylated at both alkyl chains in small rates (about 1 nmol x mg protein-1 x 60 min-1) by microsomes from rat liver and pig urinary bladder epithelium. NDBA and 4-OH-NDBA were dealkylated at similarly low rates by pig urinary bladder microsomes, in strong contrast to the high debutylation rates observed for rat liver microsomes. Correspondingly, SSB induction by NDBA and 4-OH-NDBA was observed in Namalva cells with NDBA and 4-OH-NDBA in the presence of PB-induced rat liver microsomes but not with urinary bladder microsomes or without external activation. BCPN did not induce DNA-damage in Namalva cells (with or without external activation) or in rat hepatocytes. Significant induction of sister chromatid exchanges (SCEs) and micronuclei, however, was observed in Namalva cells after incubation with NDBA and BCPN. Our data suggest activation of BCPN via alpha-oxidation in the urinary bladder, even though activation rate in-vitro is so low that a positive response is not detectable by several short-term tests. 相似文献
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Many patients still suffer from unnessesary pain in the postoperative period. Waiting for new technologies or drugs will not improve the status of acute pain management. The establishment of an acute service is needed to reduce the incidence of postoperative pain. Acute pain therapy is one of the great challenges we have to take up. 相似文献
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Perfluorochemicals as US contrast agents for tumor imaging and hepatosplenography: preliminary clinical results 总被引:3,自引:0,他引:3
Mattrey RF; Strich G; Shelton RE; Gosink BB; Leopold GR; Lee T; Forsythe J 《Radiology》1987,163(2):339-343
In animals, perfluorochemicals (PFCs) are effective ultrasound (US) contrast agents that produce hepatic, splenic, and tumor enhancement. The use of Fluosol-DA 20%, an emulsion of perfluorodecalin and perfluorotripropylamine, was studied in nine non-critically ill patients with cancer who had liver lesions. US studies without Fluosol were compared with studies obtained 24, 48, and 72 hours after Fluosol infusion. Vital signs and extensive laboratory analyses are performed before and after Fluosol infusion. Liver metastases from colonic, pancreatic, and gastric carcinoma exhibited rim or diffuse enhancement after a Fluosol dose of 1.6 g/kg or greater. Fluosol produced echogenic enhancement of the liver and spleen relative to kidney at a dose of 2.4 g/kg, allowing the detection of nonenhancing lesions. In addition, Fluosol at a dose of 1.6 g/kg or greater allowed detection of lesions not seen before contrast medium was administered in three of the seven patients studied. There was a mild increase in the level of serum glutamic oxaloacetic transaminase in two patients, one given 2.4 and the other 3.2 g/kg of Fluosol. Mild and transient allergic reactions without change in vital signs were experienced by two patients. 相似文献
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After exposure to uncontrollable shock training, two distinct groups of rats can be defined in terms of their performance in learning to escape from a controllable stress. Learned helpless rats do not learn to terminate the controllable stress, whereas non-learned helpless rats learn this response as readily as naive control rats do. The present studies were designed to examine the correlations between the behavioral differences and the changes of presynaptic serotonergic activity, seen in these groups of rats. The major findings concerned presynaptic serotonergic effects in the hippocampus and hypothalamus of learned helpless rats. In the hippocampus, these included a statistically significant increase in three presynaptic 5-hydroxytryptamine (5-HT) mechanisms: K(+)-induced release of [3H]serotonin, high affinity uptake of [3H]serotonin and maximum density of binding sites for uptake of 5-HT, measured with [3H]paroxetine. In the hypothalamus, there was a differential modulation of all three presynaptic 5-HT mechanisms. A significant decrease in: K(+)-induced release of [3H]serotonin, in high affinity uptake of [3H]serotonin and the maximum binding site density of [3H]paroxetine binding was observed. No changes in uptake site binding was seen in other regions of the brain examined. These results implicate presynaptic serotonin mechanisms in the behavioral deficit caused by uncontrollable shock. In addition, a limbic-hypothalamic pathway may serve as a control center for the behavioral response to stress. 相似文献
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