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61.
Background and purpose:
In the mammalian brain, histaminergic neurotransmission is mediated by the postsynaptic histamine H1 and H2 receptors and the presynaptic H3 autoreceptor, which also acts as a heteroreceptor. The H1 receptor has been implicated in spatial learning and memory formation. However, pharmacological and lesion studies have revealed conflicting results. To examine the involvement of histamine H1 receptor in spatial reference and working memory formation, H1 receptor knockout mice (KO) were tested in the eight-arm radial maze. Previously, we found that the H1 receptor-KO mice showed reduced emotionality when confronted with spatial novelty. As it is known that emotions can have an impact on spatial learning and memory performance, we also evaluated H1 receptor-KO mice in terms of emotional behaviour in the light–dark box.Experimental approach:
Mice lacking the H1 receptor and wild-type mice (WT) were tested for spatial reference and working memory in an eight-arm radial maze with three arms baited and one trial per day. Emotional behaviour was measured using the light–dark test.Key results:
The H1 receptor-KO mice showed impaired spatial reference and working memory in the radial maze task. No significant differences between H1 receptor-KO and WT mice were observed in the light–dark test.Conclusions and implications:
The spatial memory deficits of the H1 receptor-KO mice might be due to the reported changes in cholinergic neurochemical parameters in the frontal cortex and the CA1 subregion of the hippocampus, to impaired synaptic plasticity in the hippocampus, and/or to a dysfunctional brain reward/reinforcement system. 相似文献62.
63.
Patty H Spruit Sabine Siesling Marloes AG Elferink Ernest JA Vonk Carel JM Hoekstra 《Radiation oncology (London, England)》2007,2(1):1-6
Background
To correlate the metabolic changes with size changes for tumor response by concomitant PET-CT evaluation of lung cancers after radiotherapy.Methods
36 patients were studied pre- and post-radiotherapy with18FDG PET-CT scans at a median interval of 71 days. All of the patients were followed clinically and radiographically after a mean period of 342 days for assessment of local control or failure rates. Change in size (sum of maximum orthogonal diameters) was correlated with that of maximum standard uptake value (SUV) of the primary lung cancer before and after conventional radiotherapy.Results
There was a significant reduction in both SUV and size of the primary cancer after radiotherapy (p < 0.00005). Among the 20 surviving patients, the sensitivity, specificity, and accuracy using PET (SUV) were 94%, 50%, 90% respectively and the corresponding values using and CT (size criteria) were 67%, 50%, and 65% respectively. The metabolic change (SUV) was highly correlated with the change in size by a quadratic function. In addition, the mean percentage metabolic change was significantly larger than that of size change (62.3 ± 32.7% vs 47.1 ± 26.1% respectively, p = 0.03)Conclusion
Correlating and incorporating metabolic change by PET into size change by concomitant CT is more sensitive in assessing therapeutic response than CT alone. 相似文献64.
Barbara V. Howard Anthony Comuzzie Richard B. Devereux Sven O.E. Ebbesson Richard R. Fabsitz Wm. James Howard Sandra Laston Jean W. MacCluer Angela Silverman Jason G. Umans Hong Wang Neil J. Weissman Charlotte R. Wenger 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2010,20(5):350-358
Background and aimsAlthough Eskimos were thought to be protected from cardiovascular disease (CVD), state health data show a large proportion of deaths from CVD, despite traditional lifestyles and high omega-3 fatty acid intake. This article explores CVD prevalence and its relation to risk factors in Alaska Eskimos.Methods and resultsA population-based cohort of 499 Alaska Eskimos > age 45 from the Norton Sound region was examined in 2000–2004 for CVD and associated risk factors as part of the Genetics of Coronary Artery Disease in Alaska Natives study. CVD and atherosclerosis were evaluated and adjudicated using standardized methods. Average age was 58 years; diabetes prevalence was low and high-density lipoprotein cholesterol (HDL-C) concentrations were high, but a large proportion smoked and had high pathogen burden. CVD was higher in men (12.6%) than in women (5.3%) (prevalence ratio 2.4, CI 1.3–4.4). Rates of stroke (6.1% in men, 1.8% in women) were similar to those for coronary heart disease (CHD) (6.1% men, 2.5% women). MI prevalence was low in both genders (1.9% and 0.7%). CVD was higher in men and in those >60 years. Hypertension, diabetes, high LDL-C, high apoB, and low HDL-C were all strong correlates (<.002) and albuminuria and CRP were also correlated with CVD (p < .05) after adjustment for age and gender. Carotid atherosclerosis was correlated with CVD (p = .0079) independent of other risk factors.ConclusionThese data show high CHD and stroke prevalence in Alaska Eskimos, despite low average LDL-C and high HDL-C. Hypertension and high LDL-C were independent correlates; identifying these risk factors early and treating to target is recommended. 相似文献
65.
AG Hamburg 《MedR Medizinrecht》2001,19(1):47-49
Ohne Zusammenfassung 相似文献
66.
AG Rüsselsheim 《MedR Medizinrecht》2006,24(7):435-436
Abstrakt 1. Hinsichtlich der Frage der Anerkennung einer Heilmethode kommt es nicht darauf an, ob eine Methode von der überwiegenden
Mehrheit der sogenannten Schulmediziner anerkannt wird, aber auch nicht, ob die betreffende Methode „therapieimmanent“, also
von denjenigen, die diese Methode entwickelt haben oder sie anwenden, als wirksam eingesch?tzt wird. Entscheidend ist vielmehr
auf die Anerkennung derjenigen Personen abzustellen, die sich von dritter Seite als Wissenschaftler in einem wissenschaftlichen
Verfahren mit der Frage der Wirksamkeit der betreffenden Methode auseinandergesetzt haben.
2. Der Wirkmechanismus der Bioresonanztherapie ist nach strengen naturwissenschaftlichen Untersuchungen nicht zu erkl?ren.
Diese Methode ist jedoch von der Hufelandgesellschaft, die sich aus 25 ?rztegesellschaften zusammensetzt, die allesamt auch
Naturheilverfahren betreiben, anerkannt. (Leits?tze des Bearbeiters) 相似文献
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