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排序方式: 共有3544条查询结果,搜索用时 31 毫秒
41.
V C Abílio F M Freitas M S Dolnikoff A M Castrucci R Frussa-Filho 《Neuropsychopharmacology》1999,45(12):1622-1629
BACKGROUND: This study examines the effects of long-term continuous exposure to light on dopaminergic supersensitivity induced by repeated treatment with haloperidol in rats. METHODS: Spontaneous general activity in an open-field (SGA) and stereotyped behavior induced by apomorphine (SB-APO) or amphetamine (SB-AMP) were used as experimental parameters. Rats were allocated to four groups in each experiment: saline-treated animals kept under a 12-hour light/dark cycle (LD) or 24-hour light/light cycle (LL), and 2 mg/kg haloperidol-treated animals kept under the above cycles. Plasma corticosterone concentration was also measured by radioimmunoassay in saline-treated rats kept under a LD or LL cycle. RESULTS: All the behavioral parameters used showed the development of central dopaminergic supersensitivity in rats kept under both cycles. Continuous exposure to light enhanced SGA and SB-AMP in both saline- and haloperidol-treated rats, but did not modify SB-APO. Animals kept under the LL cycle presented an increased plasma corticosterone concentration. CONCLUSIONS: Our results suggest that continuous exposure to light leads to an increase in dopaminergic function in both normal and "supersensitive" rats. This effect seems to be mediated by a presynaptic mechanism possibly involving corticosterone actions. 相似文献
42.
Kathryn L. Chapman Michael D. Briggs Geert R. Mortier 《Fetal and pediatric pathology》2003,22(1):53-75
This review reports on multiple epiphyseal dysplasia (MED), first described clinically in the early part of the 20th century. Over 50 years later, we are now beginning to unravel the mystery behind the genetic mutations involved in triggering the changes in cartilage observed in this condition. In the past decade considerable progress has been made in identifying the underlying genetic defect in some forms of MED. Understanding the precise effect that these molecular changes have on the integrity of the cartilage extracellular matrix will lead the way in identifying the complex disease pathophysiology that defines MED. In addition, a greater understanding of the role and interactions of specific cartilage molecules may reveal the basis of more widespread cartilage disorders such as osteoarthritis. 相似文献
43.
Expression of Adhesion Molecules and Cytokines on Saphenous Veins in Chronic Venous Insufficiency 总被引:9,自引:0,他引:9
The objective of this study was to assess the relationship of signaling molecules to monocyte/ macrophages as a precursor to venous valve and venous wall dysfunction in patients with varicose veins. One of the hallmarks of venous dysfunction is destruction of venous valves with subsequent reflux and elevation of distal venous pressure. We recently observed that monocytes/macrophages migrate into the venous walls and valves of patients with venous insufficiency. There, they may play a role in the pathogenesis of primary venous insufficiency. If so, an important element in their performance would be the interaction between the monocytes and the endothelium as a precursor of damage to venous valves and the venous wall. To explore this interaction, immunohistochemistry was carried out to detect adhesion molecules and cytokines in surgical specimens removed during surgical therapy. Twenty-four surgical specimens consisting of proximal saphenous vein and subterminal valve were obtained using minimally traumatic technique in 6 males and 18 females who ranged in age from 31 to 79 years. Reflux was confirmed preoperatively by duplex technique, and severity was classified by the CEAP classification of the American Venous Forum. Ten patient limbs were class 2, eight were class 3, four were class 4, and two were class 6. The venous specimens were labeled using monoclonal antibody against ICAM-1, E-selectin, IL-1alpha, and TNF-alpha. CD68 was used for detection of monocytes/macrophages. Our results indicate that not only luminal venous endothelium but also endothelium in the vasa vasora of refluxing saphenous veins is activated, as indicated by the up-regulation of ICAM-1. However, IL-1alpha and TNF-alpha were increased in only selected specimens and are mainly detected in the vein wall. The factors that serve as trigger mechanisms to activate cells in the pathogenesis of primary venous dysfunction remain to be explored. 相似文献
44.
Cornelis P. J. Vendrik Anne Marie J. Fichtinger-Schepman Wilhelmina C. M. van Dijk-Knijnenburg W. H. de Jong Anke C. E. van der Minnen Gerard de Groot Geert Frits Berends P. A. Steerenberg 《Cancer chemotherapy and pharmacology》1997,39(6):479-485
An IgM immunocytoma cell line sensitive to cis-diamminedichloroplatinum(II) (CDDP) and a subline with acquired resistance were grown in LOU/M rats. In a previous study
with such rats that had been treated with a high dose of CDDP (10 mg/kg) the tumors did not show differences in cellular platinum
content or DNA-adduct levels, either immediately after treatment or 24 h later. Recently, this high dose was found to overcome
resistance. Therefore, the study was repeated with a 10-fold lower dose (1 mg/kg, i.v.). At 1 and 24 h after treatment, tumor
and kidney tissue were assayed for cellular platinum (atomic absorption spectroscopy, AAS) and DNA platination (immunochemical
detection of the four CDDP-DNA adducts). The results were compared with previous data. All tissues showed a linear response
to dose with regard to platinum uptake as well as adduct formation, with no quantitative difference being seen between the
tumors. Also the relative occurrence of the four adducts was very similar. Between 1 and 24 h, in tumors a substantial decrease
occurred in both platinum content and adduct level; the kidneys showed little reduction, if any. At the lower CDDP dose a
somewhat larger loss of platinum and removal of DNA adducts was observed for the resistant tumor, but these differences could
be explained by “dilution”, as this tumor continues to grow after low-dose treatment (about 20% within 24 h). Since the strong
difference observed between the tumors in sensitivity to CDDP cannot be attributed to differences in CDDP uptake, efficiency
of adduct formation, or repair capability, other mechanisms are held responsible.
Received 10 August 1995 / Accepted: 14 August 1996 相似文献
45.
Abstract Impending surgery provides a natural stress paradigm within which the effect of stress on cognitive functioning can be assessed. Cardiac patients scheduled for open-heart surgery were tested for cognitive and emotional status on the day before (N = 130) and 7 days after surgery (N = 109). We correlated the self-reported anxiety and depression scores with the performance on 11 neuropsychological tests on both pre-and postoperative examinations. The results indicate that the significantly elevated emotional arousal in these patients has no relevant effect on their cognitive performance. This finding underlines the validity of neuropsychological testing in more acute clinical settings. 相似文献
46.
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Gleason grade 4 prostate adenocarcinoma patterns: an interobserver agreement study among genitourinary pathologists 下载免费PDF全文
Charlotte F Kweldam Daan Nieboer Ferran Algaba Mahul B Amin Dan M Berney Athanase Billis David G Bostwick Lukas Bubendorf Liang Cheng Eva Compérat Brett Delahunt Lars Egevad Andrew J Evans Donna E Hansel Peter A Humphrey Glen Kristiansen Theodorus H van der Kwast Cristina Magi‐Galluzzi Rodolfo Montironi George J Netto Hemamali Samaratunga John R Srigley Puay H Tan Murali Varma Ming Zhou Geert J L H van Leenders 《Histopathology》2016,69(3):441-449
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Childhood socioeconomic conditions and teeth in older adulthood: Evidence from SHARE wave 5 下载免费PDF全文