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101.
To test the hypothesis that time of day influences the locomotor effects of cocaine in rats, we measured short- and long-term sensitization to cocaine at five different Zeitgeber times (ZT). Short-term sensitization was expressed equally at all ZTs tested. Long-term sensitization was expressed only at dark onset, suggesting a possible influence of melatonin. Exogenous melatonin given immediately before cocaine challenge slightly enhanced long-term sensitization. Taken together, the present results support a time-of-day influence on locomotor sensitization to cocaine. 相似文献
102.
Ullmann R Morbini P Halbwedl I Bongiovanni M Gogg-Kammerer M Papotti M Gabor S Renner H Popper HH 《The Journal of pathology》2004,203(3):798-807
With the appearance of defect-targeted therapies, the definition of tumour protein expression profiles has gained increasing importance. Two lung carcinoma tissue microarrays, one including 75 primary adenocarcinomas (ACs) and the other comprising 67 primary squamous cell carcinomas (SQCCs), were generated in the present study. On both arrays, each tumour was represented by an average of five cores. In addition, one punch of normal lung parenchyma adjacent to each tumour was included in the array. Immunohistochemical expression of 86 proteins was evaluated and the results were analysed by non-parametric tests, hierarchical clustering, and principal component analysis. In both tumour entities, parenchyma and tumours were clearly separated by hierarchical clustering. By the same statistical approach, it was possible to distinguish ACs from SQCCs with 98% accuracy and to distinguish parenchyma adjacent to ACs from that adjacent to SQCCs with 96% accuracy. It was also possible to separate ACs into three groups that significantly differed in survival. Cathepsin E and hsp105 were identified as previously unknown predictors of survival in lung AC. In summary, this study has shown that protein profiles are feasible tools for anticipating biological behaviour. 相似文献
103.
104.
Jaeger A Braune C Welsch F Sarikaya Y Graichen H 《Archives of orthopaedic and trauma surgery》2004,124(4):226-231
INTRODUCTION: Patients (n=62) with recurrent traumatic anterior or anteroinferior glenohumeral instability were prospectively evaluated with reference to the surgical reconstruction technique performed. MATERIALS AND METHODS: Neer's T-plasty procedure was performed in group I (n=31) while a modified, anatomically orientated, anteroinferior capsular shift was performed in group II (n=31). All patients underwent an additional Bankart repair. After 18.1 (group II) and 22.2 (group I) months, patients were assessed in terms of subjective satisfaction, objective stability, range of motion, and functional outcome. RESULTS: No significant differences (91.5% group II, 87.8% group I) were noted between the study groups regarding the patient's subjective evaluation (p=0.17106). Results of Rowe's (93.1% group II, 87.9% group I; p=0.14419) and Constant's Score (96.5% group II, 93.8% group I; p=0.16582) showed no significant differences for both collectives. Postoperative lack of external rotation remained significantly smaller in group II (5.6 degrees +/-2.5 degrees ) compared with group I (9.8 degrees +/-2.5; p=0.00028). Although no significant differences (p=0.612) were found, the rate of recurrence was obviously smaller in group II (group II vs group I: 6 patients). CONCLUSIONS: Our results demonstrate no significant differences between the two capsular reconstruction techniques regarding patient's satisfaction, Rowe and Constant Scores. However, the anatomically orientated anteroinferior capsular shift leads to a significantly smaller external rotation deficit and seems to offer a more reliable postoperative stability. 相似文献
105.
Peters O Redecker C Hagemann G Bruehl C Luhmann HJ Witte OW 《Cerebral cortex (New York, N.Y. : 1991)》2004,14(10):1081-1087
Freeze-lesion induced neocortical dysplasias in rats mimic numerous aspects of human polymicrogyria and are used as a model for the study of developmental migration disorders. Since memory tests have demonstrated learning deficits in rodents with neocortical malformations, we investigated the expression and properties of long-term potentiation (LTP) in neocortical slices from adult freeze-lesioned and control rats. Field potentials, recorded in layer II/III at a distance of 2-3 mm lateral to perinatally induced microgyri, were strongly enhanced following theta-burst stimulation in layer VI (amplitude: 174 +/- 4%) compared to controls (110 +/- 2%). In contrast, in layer IV of the freeze-lesioned cortex LTP could not reliably be induced. Histochemical analysis, performed to elucidate the cellular basis of the impaired plasticity, revealed diminished amounts of the GABAA-receptor subunit gamma2 in the paramicrogyral zone, likely representing a diminished GABA-ergic filter, which is thought to prevent LTP induced in layer VI under normal conditions. Cytochrome-oxidase staining after electrophysiological examination disclosed that LTP in layer IV of the freeze-lesioned cortex could only be elicited, when stimulation was applied within a preserved barrel cortex. Our study provides evidence that focal cryolesions during cortical development cause an impaired synaptic plasticity that may underlie learning disabilities. 相似文献
106.
We present an extremely rare case of a patient with focal hypertrophic pachymeningitis in association with histologically proven temporal arteritis (giant cell arteritis). It is proposed that focal hypertrophic pachymeningitis in itself is the contributing factor to severe headache rather than temporal arteritis alone. 相似文献
107.
Heiko C. Becker Christian M?llers Albrecht E. Melchinger Eva Bauer Jochen C. Reif 《Archives of dermatological research》2004,296(2):48-48
Editorial
Message from the new Editor-in-Chief 相似文献108.
109.
Recently it was demonstrated by Gautam, et al. that release of neutrophil-borne heparin-binding protein (HBP), also known as CAP37/azurocidin, induced endothelial hyperpermeability and neutrophil efflux. Here, we show that chronic leg ulcer fluid, in contrast to wound fluid from acute wounds, contains highly increased levels of HBP. Immunohistochemistry demonstrated the presence of HBP in chronic ulcer tissues. Furthermore, secreted products of Pseudomonas aeruginosa were found to induce release of HBP from human neutrophils. Our data suggest a possible link between bacterial presence and HBP-release in chronic ulcers. Thus, targeting HBP offers an interesting option for reduction of endothelial barrier dysfunction in chronic ulcers. 相似文献
110.
Angenstein F Niessen HG Goldschmidt J Vielhaber S Ludolph AC Scheich H 《Neuroreport》2004,15(14):2271-2274
Mice over-expressing the mutant human G93A-SOD1 are widely used as an animal model of amyotrophic lateral sclerosis (ALS). ALS is characterized by progressive degeneration of motor neurons in the motor cortex, brain stem and spinal cord. The underlying mechanisms for the selective death of motor neurons are still uncertain. To study factors that cause selective neuron degeneration or therapeutic approaches to delay the progression of the disease, a method is required to monitor the state of motor neurons under in-vivo conditions. Here, we demonstrate that in G93A-SOD1 mice the MRI signal intensities of nucleus V, VII, XII, and nucleus ambiguus show a time-dependent increase starting around day 90, parallel to first behavioral signs of a motoneuron disorder. 相似文献