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991.
Preusser M Wolfsberger S Haberler C Breitschopf H Czech T Slavc I Harris AL Acker T Budka H Hainfellner JA 《Acta neuropathologica》2005,109(2):211-216
We investigated angiogenic patterns and expression of hypoxia-related tissue factors and their prognostic impact in 100 cases of intracranial ependymoma. Angiogenic patterns were evaluated by anti-CD34 immunolabeling. Hypoxia-related factors carbonic anhydrase 9 (CA9) and hypoxia-inducible factor 1 alpha (HIF-1) were visualized by immunohistochemistry, and vascular endothelial growth factor (VEGF) mRNA by in situ hybridization. Expression patterns of VEGF and CA9 are similar with regard to distribution (perinecrotic) and extent. HIF-1 expression occurs in a significantly smaller fraction of cases and only in a few tumor cells without clear association with necrosis. Expression of VEGF and CA9, but not HIF-1, is associated with a bizarre angiogenic subtype. Combined expression of two or three hypoxia markers (high hypoxia score) associates with presence of necrosis, high proliferation index, bizarre vascular pattern, and increased cellularity. Univariate analysis indicated that patients with high hypoxia score had significantly shorter survival. On multivariate analysis, only proliferation index and extent of resection remained independent predictive factors. We conclude that bizarre vascular pattern, necrosis and high hypoxia score are frequently detectable in intracranial ependymoma, but seem less important for patient outcome than tumor cell proliferation. 相似文献
992.
NSF workshop report: Discovering general principles of nervous system organization by comparing brain maps across species
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Georg F. Striedter T. Grant Belgard Chun‐Chun Chen Fred P. Davis Barbara L. Finlay Onur Güntürkün Melina E. Hale Julie A. Harris Erin E. Hecht Patrick R. Hof Hans A. Hofmann Linda Z. Holland Andrew N. Iwaniuk Erich D. Jarvis Harvey J. Karten Paul S. Katz William B. Kristan Eduardo R. Macagno Partha P. Mitra Leonid L. Moroz Todd M. Preuss Clifton W. Ragsdale Chet C. Sherwood Charles F. Stevens Maik C. Stüttgen Tadaharu Tsumoto Walter Wilczynski 《The Journal of comparative neurology》2014,522(7):1445-1453
Efforts to understand nervous system structure and function have received new impetus from the federal Brain Research through Advancing Innovative Neurotechnologies (BRAIN) Initiative. Comparative analyses can contribute to this effort by leading to the discovery of general principles of neural circuit design, information processing, and gene‐structure‐function relationships that are not apparent from studies on single species. We here propose to extend the comparative approach to nervous system ‘maps' comprising molecular, anatomical, and physiological data. This research will identify which neural features are likely to generalize across species, and which are unlikely to be broadly conserved. It will also suggest causal relationships between genes, development, adult anatomy, physiology, and, ultimately, behavior. These causal hypotheses can then be tested experimentally. Finally, insights from comparative research can inspire and guide technological development. To promote this research agenda, we recommend that teams of investigators coalesce around specific research questions and select a set of ‘reference species' to anchor their comparative analyses. These reference species should be chosen not just for practical advantages, but also with regard for their phylogenetic position, behavioral repertoire, well‐annotated genome, or other strategic reasons. We envision that the nervous systems of these reference species will be mapped in more detail than those of other species. The collected data may range from the molecular to the behavioral, depending on the research question. To integrate across levels of analysis and across species, standards for data collection, annotation, archiving, and distribution must be developed and respected. To that end, it will help to form networks or consortia of researchers and centers for science, technology, and education that focus on organized data collection, distribution, and training. These activities could be supported, at least in part, through existing mechanisms at NSF, NIH, and other agencies. It will also be important to develop new integrated software and database systems for cross‐species data analyses. Multidisciplinary efforts to develop such analytical tools should be supported financially. Finally, training opportunities should be created to stimulate multidisciplinary, integrative research into brain structure, function, and evolution. J. Comp. Neurol. 522:1445–1453, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
993.
Sucha Nand MD Leo I. Gordon MD Elmer Brestan MD Charlotte Harris MD Thomas Brandt MD 《Cancer》1982,50(9):1882-1883
Tamoxifen is a useful agent in the management of metastatic breast cancer. We describe a patient who was treated sucessfully with Tamoxifen but developed a benign but symptomatic hepatic cyst during treatment. Development of a solitary hepatic lesion during Tamoxifen therapy should be thoroughly investigated before treatment is changed. Cancer 50:1882-1883, 1982. 相似文献
994.
Circulating endothelial progenitor cells and coronary collaterals in patients with non-ST segment elevation myocardial infarction 总被引:2,自引:0,他引:2
Lev EI Kleiman NS Birnbaum Y Harris D Korbling M Estrov Z 《Journal of vascular research》2005,42(5):408-414
BACKGROUND: Endothelial progenitor cells (EPCs) are bone marrow-derived cells that are augmented in response to ischemia and incorporated into neovascularization sites. We sought to determine whether circulating EPCs are related to collateral formation following non-ST segment elevation myocardial infarction (NSTEMI). METHODS: Twenty patients who underwent percutaneous coronary intervention (PCI) within a week of NSTEMI were divided into two groups: patients without collaterals (coll-, n=10) and patients with Rentrop grade 3--4 collaterals (coll+, n=10). Blood samples were drawn before PCI and 24+/- 2 h after PCI. EPC colonies were grown from peripheral blood mononuclear cells, characterized, and counted. Using flow cytometry the percentage of cells co expressing vascular endothelial growth factor receptor-2 and CD 133 was determined. RESULTS: The coll+ group had higher degree of culprit vessel stenosis and lower initial thrombolysis in myocardial infarction flow grade. The relative number of EPCs before PCI was significantly higher in the coll+ group than in the coll- group (1.49 +/- 0.9% vs. 0.77+/- 0.4%, p= 0.045). There were no significant intergroup differences in the number of EPC colony-forming cells. The number of EPC colonies increased in the coll- group after PCI (9.5 +/- 4.8 to 14.0 +/- 5.9/10(6) cells, p=0.01). CONCLUSIONS: This study supports an association between circulating EPC levels and collateral formation in patients with an NSTEMI. 相似文献
995.
J Timsit P Chanson E Larger M Duet A Mosse P J Guillausseau A G Harris M Moulonguet A Warnet J Lubetzki 《Acta endocrinologica》1987,116(1):108-112
Multiple sc injections of a long-acting somatostatin analogue (SMS 201-995) are currently used in the treatment of acromegaly. However, plasma GH concentration often reaches a pathological level (less than 5 micrograms/l) between two injections. In seven patients with active acromegaly we compared, in a short-term trial, the effect of SMS 201-995 administered by continuous sc infusion (50 micrograms and 100 micrograms a day) and by three sc injections (100 micrograms each). In six patients, plasma GH levels were significantly reduced regardless of the mode and dose of treatment (P less than 0.05). However, comparing diurnal profiles, 100 micrograms continuous sc infusion was more effective than discontinuous administration in reducing the number of GH levels above 5 micrograms/l (P less than 0.01). In two patients, continuous infusion was the only way to decrease all plasma GH values below 5 micrograms/l during the diurnal profile determination. Moreover, even when, in a long-term study, the dose of multiple injections was progressively increased to 500 micrograms three times a day, GH levels remained consistently elevated in one of these patients. Thus, in some acromegalic patients continuous sc injection seems currently the most efficient way of treatment with SMS 201-995. 相似文献
996.
G S Roubin N A Sadick S D Anderson S Devenish-Meares P J Harris D T Kelly 《The American journal of cardiology》1987,60(4):249-255
Oxygen utilization, arterial and venous blood gas levels, hemodynamic values and exercise tolerance were compared before and after administration of propranolol and verapamil in 10 patients with stable angina pectoris. During exercise, propranolol decreased cardiac output (CO) by 22%; O2 extraction was increased and O2 consumption (VO2) did not change. With verapamil treatment, CO modestly increased (7%), O2 extraction decreased and VO2 did not change. In contrast to O2 utilization, the drugs produced opposite changes in mixed venous and arterial blood gas levels. Propranolol decreased mixed venous pH, increased CO2 tension and decreased the pH of arterial blood. Verapamil increased venous pH and decreased CO2 tension; pH of arterial blood did not change. The drugs yielded similar levels of antianginal efficacy, but patients exercised longer during verapamil therapy and were less fatigued. The hemodynamic and metabolic differences suggest that muscle perfusion during exercise influences the onset of fatigue and may help determine the choice of therapy. 相似文献
997.
Arterial and coronary sinus difference for potassium, lactate, glucose, free fatty acids and creatine kinase was measured every 5 minutes in two patients undergoing successful intracoronary thrombolysis of left anterior descending occlusion. In the first patient, reperfusion, 160 minutes after the onset of pain, was followed by a transient and limited release of creatine kinase in the coronary sinus, improvement in the electrocardiogram and restitution of left ventricular contraction. In the second patient, reperfusion 365 minutes after the onset of pain, was also accompanied by a limited release of creatine kinase. Reocclusion of the left anterior descending coronary artery, however, necessitated further thrombolysis which led to a massive release of creatine kinase and permanent loss of wall-motion. It is suggested that, in this case, reperfusion damage had occurred. The arteriovenous differences showed a wash-out of potassium and lactate during reperfusion in each case. The interpretation of the entire sequence of arteriovenous changes, however, could be shown to depend critically on the state of regional perfusion. 相似文献
998.
Differences in ambulatory test ordering in England and America. Role of doctors' beliefs and attitudes 总被引:1,自引:0,他引:1
Forty-five American and English doctors were surveyed to determine whether differences in their beliefs about the incidence and morbidity of complications and the role of testing for patients with chronic hypertension could be contributing to the large cross-national differences previously demonstrated in ambulatory test use for such patients. For each of nine tests, the number the English doctors thought they "should order" was significantly less than that of the American group. English doctors also estimated a lower incidence for each of seven possible complications of hypertension, but there was no difference in perceived morbidity of the complications. Both groups thought results from testing would alter therapy for only a small proportion of patients; however, the English estimate was significantly smaller than the American (16 percent versus 27 percent: p less than 0.05). The reasons given for testing were very similar in the two countries except that American doctors ranked as more important the reason that patients used the quantity of test ordering as an indicator of quality care. These results suggest that differences in ambulatory test use are consistent with physicians' beliefs about the number of tests they should be ordering, disease incidence, the likelihood that testing will affect patient care, and patient expectations. Further study should be directed toward understanding the contributions that differences in physician beliefs about the natural histories of diseases and patient expectations make to variations in test ordering. 相似文献
999.
1000.
胃、结直肠癌术前区域性动脉化疗几个相关问题 总被引:2,自引:0,他引:2
胃、结直肠癌根治性切除术复发转移是严重影响术后5 a生存率提高的重要原因.以手术为主综合治疗已成为新的趋势,其中术前区域性动脉化疗(preoperative regional-arterial chemotherapy,PRAC)尤为值得重视.本文介绍了术前PRAC的概念、作用机制和影响区域性动脉化疗疗效的相关因素,并就术前区域性动脉化疗在胃、结直肠癌综合治疗中的评价进行讨论. 相似文献