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991.
992.
OBJECTIVE: To analyze the effects in vitro of alpha- and beta-adrenoceptor agonists on splenocyte proliferation and on proinflammatory cytokine production in splenocytes and peritoneal macrophages (MF) in different stages of EAE. METHODS: Splenocytes and peritoneal macrophages were harvested in the acute phase of EAE and in remission, and from controls. The beta-agonist terbutaline, the alpha(1)-agonist methoxamine, and the alpha(2)-agonist UK-14304 were added with ConA or lipopolysaccharide (LPS). TNF-alpha and IFN-gamma contents in supernatant and splenocyte proliferation were determined. RESULTS: Terbutaline and UK-14304 significantly suppressed TNF-alpha production by MF. However, EAE acute phase rats were resistant to the suppressive effect of UK-14304. Terbutaline significantly suppressed IFN-gamma and TNF-alpha production by splenocytes. EAE acute phase and remission animals showed reduced terbutaline-induced inhibition of IFN-gamma production. CONCLUSIONS: Disturbed sympathetic-immune communication in EAE is characterized by alterations in adrenergic sensitivity via both alpha- and beta-adrenergic pathways.  相似文献   
993.
Moderate hypothermia and application of brain-derived neurotrophic factor (BDNF) have separately been identified as neuroprotective strategies in experimental cerebral ischemia. To assess their separate and combined effects on striatal glutamate release in the hyperacute phase of stroke, we inserted microdialysis probes into the striatum of rats 2 h before permanent middle cerebral artery occlusion (MCAO). The animals (N = 28) were randomly assigned to one of four treatment strategies commencing 30 min after MCAO: (1) hypothermia at 33 degrees C (n = 7); (2) intravenous BDNF infusion [300 microg/(kg/h) for 2 h, n = 7]; (3) combination of hypothermia and BDNF (n = 7); (4) control group (saline, n = 7). Infarct size at 5 h after MCAO was assessed with the silver-staining method. Total infarct volume was significantly reduced in the hypothermia (202.7 +/- 3.5 mm(3), P = 0.0002) and BDNF group (206.5 +/- 6.9 mm(3), P = 0.0006) as compared to control group (254.4 +/- 9.3 mm(3)). In the combination group, infarct size was further reduced with overall significance in post hoc tests (157.3 +/- 6.2 mm(3), P < 0.0001). Postischemic glutamate concentrations in the control group constantly remained significantly higher than in all other treatment groups. At 255 and 270 min after MCAO, striatal glutamate in the combination group decreased significantly more than in animals treated with hypothermia or BDNF alone.Combining hypothermia and BDNF therapy in the acute stage of ischemia has a synergistic effect in attenuating striatal glutamate release and reducing early infarct size.  相似文献   
994.
995.
OBJECTIVES: In the past, some moonshine products contained potentially toxic contaminants. Although moonshine production continues in the United States, no studies have analyzed the content of moonshine since the early 1960s. We hypothesize that moonshine continues to contain potentially toxic concentrations of contaminants. METHODS: Forty-eight samples of illicitly distilled moonshine were obtained from law enforcement agencies. An independent laboratory, blinded to both the moonshine source and a control sample of ethanol, conducted the analysis. Lead content was determined using atomic absorption spectrophotometry with a graphite tube atomizer. Alcohol content, including ethanol, acetone, isopropanol, methanol, and ethylene glycol, was determined using gas liquid chromatography with flame ionization detection. RESULTS: Ethanol content ranged from 10.5% to 66.0% with a mean value of 41.2%. Lead was found in measurable quantities in 43 of 48 samples with values ranging from 5 to 599 parts per billion (ppb) with a mean value of 80.7 ppb. A total of 29 of 48 (60%) of samples contained lead concentrations above or equal to the EPA water guideline of 15 ppb. Methanol was found in only one sample at a concentration of 0.11%. No samples contained detectable concentrations of acetone, isopropanol, or ethylene glycol. CONCLUSIONS: Many moonshine samples contain detectable concentrations of lead. Extrapolations based on the described moonshine lead content suggest that chronic consumers of moonshine may develop elevated lead concentrations. Physicians should consider lead toxicity in the differential diagnosis when evaluating patients consuming moonshine.  相似文献   
996.
Tumor interstitium exhibits a microenvironment that differs from corresponding normal tissues. Tumor phenotype shows, for example, an elevated intracellular pH (pHi), a lowered extracellular pH (pHe), a low oxygen concentration and low glucose levels. These differences are caused by cell biological (so called intrinsic) factors, e.g. a higher acidification rate, as well as by more systemic (extrinsic) factors, e.g. poor tumor vascularization. They represent important factors for invasiveness, immune suppression and proliferation, and they imply possibilities for diagnosis, prognosis and therapy. We have developed an experimental data-based computer model, which has simulated the potential role of metabolic effects on tumor progression. We show an experiment on cellular metabolism demonstrating the immunosuppressive impact of low pHe on peripheral blood mononuclear cells. Finally, we review important findings on the tumor microenvironment leading to possibilities for therapy which are currently evolving and which promise higher effectiveness for cancer therapy.  相似文献   
997.
PURPOSE: To study the effects of internal limiting membrane (ILM) peeling, usually performed in cases of macular hole formation, on the structural integrity of the human retina. DESIGN: Experimental study. MATERIAL: Two human donor eyes. METHODS: A human donor retina was subjected to ILM peeling shortly after enucleation, fixed, and studied by electron microscopy. MAIN OUTCOME MEASURES: Electron microscopic findings. RESULTS: Within the peeled area, and even at its margins, a substantial number of Müller (glial) cell endfeet and vitreal Müller cell processes was severely damaged. However, many glial cells remained intact, and the cell bodies of the injured cells showed no signs of destruction. CONCLUSIONS: We have shown that ILM peeling results in minor, but demonstrable, damage of the adjacent retina. Clinical studies are required to demonstrate unequivocally that ILM peeling does not induce functional deficits rather than improvement of visual function.  相似文献   
998.
At the Framingham Heart Study under separate research grant funding from the National Institute of Aging, NIH, we are gathering brain structure and cognitive information on the Framingham Offspring, creating one of the largest known data sets to assess changes in brain structure associated with normative ageing and cognitive decline. Subject recruitment, data collection, data management and statistical analysis require a collaborative integrated effort on the part of the Framingham project team. Here we describe this effort, as well as the various brain structure and cognitive function parameters we are now collecting. We are currently performing analyses of data collected through 2002, and we discuss the statistical issues arising relating brain structure parameters to cognitive function.  相似文献   
999.
Self-help groups have found increasing recognition by health professionals in recent years. However, considerable research deficits remain, particularly regarding self-help groups for persons with psychiatric and psychosomatic disorders. We present a survey on the dissemination and differentiation of such groups in Germany and their support by self-help advice centres. Most likely, more than 5,000 of these groups exist covering a broad range of psychiatric disorders, particularly groups for families and partners, bereavement, anxiety disorders, depression, and eating disorders. These groups are supported by self-help advice centres in various ways from information to group counselling in difficult periods. The results of the survey encourage further in depth study of self-help groups, their cooperation with psychotherapists, and their health promoting potentials.Funded by BKK Bundesverband, project grant Self-help groups for psychiatric and psychosomatic disorders.  相似文献   
1000.
Classic Hodgkin's lymphoma is characterised by Hodgkin and Reed-Sternberg cells and in most cases are derived from germinal-centre B cells. Despite progress in basic research showing the natural precursor cells of Hodgkin's lymphoma, most key questions still remain unanswered. Among these are the basic transforming events, the involvement of oncogenic viruses, the mechanisms enabling Hodgkin and Reed Sternberg cells to resist apoptosis in the germinal centre, and the molecular causes of their characteristic phenotype. Beyond the disclosure of these issues, the detection of changes in gene expression, gene mutations, and chromosomal imbalances specific of Hodgkin's lymphoma are central to recent research that may allow one a better understanding of the natural history of this type of lymphoma.  相似文献   
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