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831.
J.-P. Coudereau Marcel Debray Claire Monier Jean-Marie Bourre Henriette Frances 《Psychopharmacology》1997,130(2):117-123
Morphine (8–100 mg/kg IP) induces place preference conditioning in mice. The effect of two different periods of isolation
(15 and 30 days) was examined. Mice isolated for 15 days but not 30 days exhibited place preference conditioning to morphine
(8 mg/kg). After 30 days of isolation morphine could not induce place preference conditioning with the following doses (8, 16, 64, 100 mg/kg).
Social regrouping of male mice previously isolated for 30 days with naive female mice for 15 or 30 days resulted in a reappearance
of the conditioned place preference to morphine (16 mg/kg). The specificity of this associative deficit was examined by testing
learning in isolated compared to non-isolated mice in two distinct settings: escape learning in the Morris water maze and
passive avoidance acquisition and retention. On the Morris water maze isolated mice did not differ from non-isolated mice
regarding place learning, the probe trial or extinction. Isolated mice were unimpaired in passive avoidance acquisition and
retention. It was concluded that the deficits in place preference conditioning were not the result of a global learning impairment
in isolated mice.
Received: 10 April 1996 /Final version: 20 September 1996 相似文献
832.
Veena Kumari Jeffrey A. Gray Philip J. Corr Owen F. Mulligan Paul A. Cotter Stuart A. Checkley 《Psychopharmacology》1997,129(3):271-276
The effects of an indirect dopamine-agonist, d-amphetamine, and a non-selective dopamine receptor antagonist, haloperidol, were investigated in normal male volunteers using
a between-subjects double-blind design in a procedural learning task, thought mainly to involve unconscious/automatic learning.
The results showed: (1) d-amphetamine facilitated response speed, whereas haloperidol inhibited it, in comparison to placebo; (2) the linear increase
in procedural learning corresponded with pharmacological manipulation of degree of dopaminergic activity, i.e. subjects given
haloperidol showed the least, and subjects given d-amphetamine the greatest, procedural learning. The implications of these findings are discussed in relation to investigation
of abnormalities of procedural learning processes in schizophrenia.
Received: 28 June 1996/Final version: 2 October 1996 相似文献
833.
H. Nilsson J. Johansson K. Svanberg S. Svanberg G. Jori E. Reddi A. Segalla D. Gust A. L. Moore T. A. Moore 《British journal of cancer》1997,76(3):355-364
The biodistribution of two recently developed tumour markers, trimethylated (CP(Me)3) and trimethoxylated (CP(OMe)3) carotenoporphyrin, was investigated by means of laser-induced fluorescence (LIF) after i.v. injection into 38 tumour-bearing (MS-2 fibrosarcoma) female Balb/c mice. At 3, 24, 48 or 96 h after administration, the carotenoporphyrin fluorescence was measured in tumoral and peritumoral tissue, as well as in the abdominal, thoracic and cranial cavities. The fluorescence was induced by a nitrogen laser-pumped dye laser, emitting light at 425 nm, and analysed by a polychromator equipped with an image-intensified CCD camera. The fluorescence was evaluated at 490, 655 and 720 nm: the second and third wavelengths represent the carotenoporphyrin (CP)-related peaks, whereas the first one is close to the peak of the tissue autofluorescence. The tumour and the liver were the two tissue types showing the strongest carotenoporphyrin-related fluorescence, whereas the cerebral cortex and muscle consistently exhibited weak substance-related fluorescence. In most tissue types, the fluorescence intensities decreased over time. A few exceptions were observed, notably the liver, in which the intensity remained remarkably constant over the time period investigated. 相似文献
834.
A wound, in the broadest sense, is a disruption of normal anatomic structure and function. Acute wounds progress through a timely and orderly sequence of repair that leads to the restoration of functional integrity. In chronic wounds, this timely and orderly sequence goes awry. As a result, people with chronic wounds often face not only physiological difficulties but emotional ones as well. The study of body image and its damage as a result of a chronic wound fits well with Selder's transition theory. This article describes interviews with seven patients with chronic wounds. The themes that emerged from those interviews were compared with Selder's theory to describe patients' experience with chronic wounds as a transition process that can be identified and better understood by healthcare providers. 相似文献
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839.
A. Heinig S. H. Heywang-Köbrunner P. Viehweg D. Lampe J. Buchmann R. P. Spielmann 《Der Radiologe》1997,37(9):710-717
Summary
Early recognition of recurrence and work-up of clinically indeterminate lesions may be impaired after reconstruction with
silicone implants due to superimposition of the implant or to scarring. This study was undertaken to evaluate the use of contrast-enhanced
MRI in patients with silicone implant after breast cancer. Contrast-enhanded MRI was offered to 169 patients. Comparative
two- to three-view mammography was also performed in 169 patients, as well as comparative sonography in 144 patients. Conventional
imaging and clinical examination detected only 8/13 recurrences, whereas 12/13 were detected by MRI. One recurrence had been
visible as a strongly enhancing 2-mm dot in a previous examination (2 years before), but was not called. It was therefore
counted as false negative. In addition, multicentricity was detected by MRI alone in two of three cases. MRI correctly diagnosed
scar tissue in all cases with indeterminate findings. However, due to false-positive calls caused by enhancing granulomas
specificity could not be improved. Contrast-enhanded MRI allowed decisive additional information in our study group and improved
the sensitivity significantly (concerning all diagnoses). Contrast-enhanded MRI is recommended in patients with diagnostic
problems or high risk of recurrence after silicone implants.
相似文献
840.