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101.
Chronic morphine treatment produced increases in [3H]-flunitrazepam binding in some hippocampal areas of the rat brain. The differences in binding were statistically significant in some cases. Both morphine-dependent and morphine-deprived (abstinence syndrome) animals showed an identical response in binding, which confirms a real, although small, increase in benzodiazepine binding sites in the hippocampus after morphine treatment, that is not affected by a naloxone-induced abstinence syndrome under the conditions studied. These findings support the hypothesis of a morphine-induced up-regulation of benzodiazepine binding sites in the hippocampus. A possible different response in benzodiazepine binding sites 1 and 2 could explain the different findings reported in the literature. Our data suggest that the detected increase in benzodiazepine binding would be mainly due to type 2 binding sites, since the hippocampus has a higher density of this type of benzodiazepine binding sites. 相似文献
102.
Physician/patient decision aids for adjuvant therapy. 总被引:2,自引:0,他引:2
103.
Patric M Schiltz German G Gomez Susana B Read Nisha V Kulprathipanja Carol A Kruse 《Journal of interferon & cytokine research》2002,22(12):1209-1216
To enhance the efficacy of cellular immunotherapy for gliomas, we tested the concept of using proinflammatory cytokine treatment with interferon-gamma (IFN-gamma) or interleukin-1beta (IL-1beta) or both to render glioma cells more susceptible to cytolysis by alloreactive cytotoxic T lymphocytes (aCTL). The cytokines, separately or in combination, were able to upregulate major histocompatibility complex (MHC) class I antigen or intercellular adhesion molecule-1 (ICAM-1) on Fischer rat 9L gliosarcoma cells. 9L cells were incubated in vitro for 24, 48, or 72 h with varying concentrations of rat IFN-gamma (0-2000 U/ml) or recombinant human IL-1 (rHUIL-1) (0-1000 U/ml) or both. By 48 h, IFN-gamma (500 U/ml) maximally induced the percentage of positive expressing cells and the relative antigen density of MHC class I and ICAM-1 on 9L cells, whereas IL-1 induced only ICAM-1 expression. Simultaneous incubation of IL-1 with IFN-gamma did not further affect the induction of class I on 9L cells more than that achieved with IFN-gamma alone. 9L cells with upregulated MHC class I and ICAM-1 expression were more sensitive to lysis by aCTL in in vitro cytotoxicity assays, regardless of whether the precursor aCTL came from naive or from 9L-immunized rats. Furthermore, inhibition of 9L cytotoxicity in assays that included blocking antibodies to MHC class I or to ICAM-1 revealed that T cell receptor (TCR) interactions with MHC class I and that ICAM-1 interactions with lymphocyte function-associated-1 (LFA-1) antigen account for a portion of the glioma lysis by aCTL. 相似文献
104.
Renato S. Gomez L. O. F. Andrade J. R. Rezende Costa 《Journal canadien d'anesthésie》1997,44(7):732-734
Purpose To present a case of brainstem anaesthesia as a complication of peribulbar anaesthesia.
Clinical features A 75-yr-old woman received peribulbar anaesthesia for cataract surgery. A few seconds after the block was performed, she had
a respiratory arrest, became unconscious, and developed hypertension and tachycardia followed by hypotension and bradycardia.
Ventilatory and haemodynamic support were performed before the patient regained adequate spontaneous breathing and normal
heart rate and blood pressure.
Conclusion Peribulbar anaesthesia generally cames a low risk of serious complications. However, respiratory arrest and brainstem anaesthesia
may occur as complications of peribulbar blocks.
Résumé Objectif Présenter un cas d’anesthésie du tronc cérébral compliquant une anesthésie péribulbaire. éléments cliniques Un bloc péribulbaire était réalisé chez une femine de 75 ans pour l’extraction d’une cataracte. Quelques secondes après l’injection, la patiente cessait de respirer et perdait conscience. Elle devenait hypertendue et tachycarde puts hypotendue et bradycarde. La ventilation et la circulation devaient être supportées jusqu’au retour spontané à la normale. Conclusion En général, l’anesthésie péribulbare comporte un faible risque de complications sérieuses. Un arrêt respiratoire par anesthésie du tronc cérébral est toujours possible.相似文献
105.
106.
Demetrius M Maraganore Mariza de Andrade Timothy G Lesnick Matthew J Farrer James H Bower John A Hardy Walter A Rocca 《Movement disorders》2003,18(6):631-636
The identification of pathogenic mutations in the three genes alpha-synuclein, parkin, and ubiquitin carboxy-terminal hydrolase L1 (UCHL1) has elucidated the ubiquitin proteasome system (UPS) and its potential role as a causal pathway in Parkinson's disease (PD). In addition, polymorphisms of these three genes have been shown to be independently associated with PD. In a sample of 298 unrelated PD cases and 185 controls, we applied a two-phased approach of recursive partitioning and logistic regression analyses to explore complex interactions. For women only, we observed an epistatic interaction of UCHL1 and alpha-synuclein genotypes with significant effects on PD risk (odds ratio = 2.42; P = 0.003). Our findings are consistent with the hypothesis that PD is a multigenic disorder of the UPS. 相似文献
107.
Standing posture is made possible by hip extension and lumbar lordosis. Lumbar lordosis is correlated with pelvic parameters, such as the declivity angle of the upper surface of the sacrum and the incidence angle, which determine the sagittal morphotype. Incidence angle, which is different for each individual, is known to be very important for upright posture, but its course during life has not yet been established. Incidence angle was measured on radiographs of 30 fetuses, 30 children and 30 adults, and results were analysed using the correlation coefficientr and Student's t test. A statistically significant correlation between age and incidence angle was observed. Incidence angle considerably increases during the first months, continues to increase during early years, and stabilizes around the age of 10 years. Incidence is a mark of bipedism, and its role in sagittal balance is essential. 相似文献
108.
Thedevelopmentinmicrosurgicaltechniqueshasgreatlyimprovednervefunctionalrecovery .However ,owingtotheinabilitytocoaptateandsuturethousandsofnervefiberstotheirfunctionallysimilarnervefibersandinaccuratesutureofthenervestumps ,regeneratednervefiberspartiallylosethechancetoselectivelyregrowintotheirtargetendoneurialtubes,1 4whichresultsinaninevitablemismatchofmotorandsensorynervefibers .Thus,thecontact guidance basedmicrosurgicalnerverepairhasfailedtoachieveconsistentsatisfactoryfunctionalrecover… 相似文献
109.
A 68-year-old man receiving long-term therapy with oral sustained-release theophylline 450 mg twice/day was admitted to the hospital after failing treatment with azithromycin for an acute exacerbation of obstructive lung disease. Peak serum theophylline concentration was 20 μg/ml (normal 10–20 μg/ml). Azithromycin was discontinued and the theophylline dosage reduced by 33%. The subsequent 80% decrease in serum theophylline to 4.6 μg/ml was unexpectedly large. Two rechallenges produced similar transient depressions of serum theophylline concentrations after withdrawal of azithromycin, suggesting an interaction. Withdrawal of azithromycin may leave an increased number of active enzyme sites available as the drug is cleared from the system. In some circumstances, it may be useful for pharmacokinetic interaction studies to continue measuring concentrations after the suspected interacting agent is stopped. 相似文献
110.
Folding of the conserved domain but not of flanking regions in the integrin β2 subunit requires association with the α subunit 下载免费PDF全文
Chichi Huang Chafen Lu Timothy A. Springer 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(7):3156-3161
We have used immunoprecipitation with mAbs to probe folding during biosynthesis of the β2 integrin subunit of lymphocyte function-associated antigen 1 (LFA-1; CD11a/CD18) before and after association with the αL subunit. An evolutionarily conserved region is present in the β2 subunit between amino acid residues 102 and 344. mAbs to one subregion before the conserved region, and two subregions after the conserved domain, immunoprecipitated both the unassociated β′2 precursor and mature αL/β2 complex, suggesting portions of these subregions are folded before association with αL. An activating mAb to the C-terminal cysteine-rich region, KIM127, preferentially bound to the unassociated β subunit, suggesting that it may bind to an epitope that is in an αβ interface in unactivated LFA-1. By contrast, mAbs to five different epitopes in the conserved region did not react with unassociated β′2 precursor, suggesting that this region folds after αL association and is intimately associated with the αL subunit in the αL/β2 complex. mAbs to two different epitopes that involve the border between the conserved region and the C-terminal segment, were fully or partially reactive with the β′2 precursor, suggesting that this region is partially folded before association with αL. The findings suggest that the conserved region is a distinct folding and hence structural unit, and is intimately associated with the α subunit. 相似文献