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71.
Maria Grazia Daidone Rosella Silvestrini Nadia Zaffaroni Egle Grignolio Fabio Landoni 《Investigational new drugs》1987,5(3):245-250
An in vitro assay, which evaluates drug effect on 3H-thymidine incorporation, was used to investigate the absolute and relative activities of cisplatin (DDP), carboplatin (CBDCA) and iproplatin (CHIP) on 317 specimens from untreated tumors, including breast and ovarian cancers and malignant melanomas. Similar activities were generally observed for DDP and CHIP, whereas CBDCA exhibited a lower, although not significantly different cytotoxicity on breast and ovarian cancers. The relative activities of Platinum analogues were analyzed on 239 two-way drug sensitivity comparisons. The overall agreement rates ranged from 80.2 to 83.9% for the different comparisons. High coresistance, from 61.1 to 93.8%, was observed for all the comparisons, regardless of the tumor type. Cosensitivity rates were poor for breast and ovarian cancers, from 0 to 37.5%, whereas for melanomas an association in sensitivity was observed in 80% of the cases. 相似文献
72.
73.
74.
Recent longitudinal studies using personality questionnaires and ratings have shown remarkable stability across the adult years. In an investigation of age changes and differences in personality as measured by the Holtzman Inkblot Technique (HIT), ninety-three men and women aged twenty-five to ninety were administered Form A of the HIT; forty-four of these were retested one to three years later. Stability coefficients ranged from .07 for Form Appropriateness to .73 for Form Definiteness, with most variables showing significant but moderate stability. Repeated measures analyses of variance showed increases in six variables and decreases in two others, but only one of these changes was paralleled by cross-sectional age differences. Correlations with self-report measures of the broad personality domains of neuroticism, extraversion, and openness to experience failed to show hypothesized relations, and the associations seen were attributable to chance. It was concluded that the HIT measures perceptual-cognitive variables that are moderately stable in adulthood. 相似文献
75.
Muscarinic receptor-stimulated phosphoinositide metabolism has been recently suggested as a possible target for the neurotoxic effects of ethanol during brain development. Since two other alcohols, tertiary butanol and n-propanol, have been shown to cause microencephaly in the rat when administered during the brain growth spurt, in the present study we investigated the in vitro effects of five short chain aliphatic alcohols on muscarinic receptor-stimulated phosphoinositide metabolism in cerebral cortical slices from 7 day-old rats. In neonatal animals all alcohols tested inhibited carbachol (1 mM)-stimulated [3H]inositol phosphates accumulation in a dose- and time-dependent manner. The order of potency was t-butanol greater than n-propanol greater than or equal to iso-propanol greater than ethanol greater than methanol. After 90 min of incubation, ethanol, n-propanol and t-butanol caused a significant inhibition of muscarinic receptor-stimulated inositol metabolism at doses as low as 15 - 50 mM, comparable to the blood concentrations reached after in vivo administration of doses able to induce developmental neurotoxicity. The inhibitory effect of ethanol was additive to that of iso-propanol or t-butanol. Differently from these effects in 7 day-old rats, in cortical slices from adult animals methanol and ethanol had no effect on carbachol-stimulated phosphoinositide metabolism, while the two propanol isomers and t-butanol were less effective than in neonatal animals. These results suggest that muscarinic receptor-coupled phosphoinositide metabolism might be a common neurochemical target for the developmental neurotoxicity of short chain aliphatic alcohols. 相似文献
76.
77.
Paavo Riekkinen Jr. Jouni Sirvi Pekka Jkl Maria Mazurkiewicz Antti Valjakka Minna Riekkinen Paavo Riekkinen 《Brain research bulletin》1991,27(2):287-289
Quisqualic acid NBM lesions had no effect on water maze performance, but slightly impaired passive avoidance acquisition. GammavinylGABA treatment alone had no effect on the passive avoidance and water maze performance, but aggravated acquisition deficit in rats subjected to NBM lesioning. However, gammavinylGABA-treated NBM-lesioned rats reached control level of performance. 相似文献
78.
Marina Quartu Maria Pina Serra Annalisa Manca Paolo Follesa Rossano Ambu Marina Del Fiacco 《International journal of developmental neuroscience》2003,21(6):309-320
The immunohistochemical occurrence of the high affinity neurotrophin (NT) receptors trkA, trkB, and trkC is shown in the pre-term newborn, infant, and adult human post-mortem cerebellum. Immunoreactive neuronal perikarya and processes were observed in all specimens examined, where they appeared unevenly distributed in the cerebellar cortical layers and deep nuclei, and showed regional differences among cerebellar lobules and folia. The trk receptor-antibodies, tested by Western blot on human cerebellum homogenates, revealed multiple immunoreactive bands for trkA and single bands for trkB and trkC. The results obtained show the tissue localization of the trk receptor-like immunoreactivity in the human cerebellum from prenatal to adult age. The analysis for codistribution of the receptors with the relevant ligand and among the receptors in discrete cortical and deep nuclei tissue fields shows a wide variety of conditions, from a good similarity in terms of type and density of labeled structures, to a lack of correspondence, and suggests the possibility of colocalization of trk receptors with the relevant neurotrophin and among them in the cerebellar cortex. These results sustain the concept that the neurotrophin trophic system participates in the development, differentiation, and maintenance of the human cerebellar connectivity and support the possibility of a multifactorial trophic support for the neurotrophins through target-derived and local mechanisms. 相似文献
79.
Presenting a clinical case, the authors reveal the possible cholesteatoma complications arising from otospongious surgery. He notice that there are very few literature about similar cases. Underlining the rarity of this complication, the authors will put forward concisely the principal etiological mechanisms occurring in this kind of pathology. Since the reoperation must often be carried out on fragile inner ears, the authors stress on the necessity to respect the elementary rules of prevention in order to avoid the formation of precholesteatoma states. 相似文献
80.
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