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111.
The psychophysiology of real-time financial risk processing 总被引:6,自引:0,他引:6
A longstanding controversy in economics and finance is whether financial markets are governed by rational forces or by emotional responses. We study the importance of emotion in the decision-making process of professional securities traders by measuring their physiological characteristics (e.g., skin conductance, blood volume pulse, etc.) during live trading sessions while simultaneously capturing real-time prices from which market events can be detected. In a sample of 10 traders, we find statistically significant differences in mean electrodermal responses during transient market events relative to no-event control periods, and statistically significant mean changes in cardiovascular variables during periods of heightened market volatility relative to normal-volatility control periods. We also observe significant differences in these physiological responses across the 10 traders that may be systematically related to the traders' levels of experience. 相似文献
112.
Kelmanson IV Shagin DA Usman N Matz MV Lukyanov SA Panchin YV 《The European journal of neuroscience》2002,16(12):2475-2476
Neurons can communicate with each other either via exchange of specific molecules at synapses or by direct electrical connections between the cytoplasm of either cell [for review see Bruzzone et al. (1996) Eur. J. Biochem., 238, 1-27]. Although electrical connections are abundant in many nervous systems, little is known about the mechanisms which govern the specificity of their formation. Recent cloning of the innexins--gap junction proteins responsible for electrical coupling in invertebrates (Phelan et al. (1998) Trends Genet., 14, 348-349], has made it possible to study the molecular mechanisms of patterning of the electrical connections between individual neurons in model systems. Here we demonstrate that intracellular injection of mRNA encoding the molluscan innexin Panx1 (Panchin et al. 2000 Curr. Biol., 10, R473-R474) drastically alters the specificity of electrical coupling between identified neurons of the pteropod mollusc Clione limacina. 相似文献
113.
Vielhaber S Varlamov DA Kudina TA Schröder R Kappes-Horn K Elger CE Seibel M Seibel P Kunz WS 《Journal of neuropathology and experimental neurology》2002,61(10):885-895
To assess the detailed expression pattern of mitochondrial-encoded proteins in skeletal muscle of patients with mitochondrial diseases we performed determinations of cytochrome content and enzyme activities of respiratory chain complexes of 12 patients harboring large-scale deletions and of 10 patients harboring the A3243G mutation. For large-scale deletions we observed a mutation gene dose-dependent linear decline of cytochrome aa3 content, cytochrome c oxidase (COX) activity, and complex I activity. The content of cytochromes b and the complex III activity was either not affected or only weakly affected by the deletion mutation and did not correlate to the degree of heteroplasmy. In contrast, in skeletal muscle harboring the A3243G mutation all investigated enzymes containing mitochondrial-encoded subunits were equally affected by the mutation, but we observed milder enzyme deficiencies at a comparable mutation gene dose. The results of single fiber analysis of selected biopsies supported these findings but revealed differences in the distribution of COX deficiency. Whereas predominantly type I fibers were affected in A3243G and deletion CPEO biopsies, we observed in MELAS and KSS biopsies higher quantities of COX-deficient type 2 fibers. Our findings indicate different pathomechanisms of deletion and A3243G mutations. 相似文献
114.
Chen J Körner S Craig SL Lin S Rudkevich DM Rebek J 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(5):2593-2596
Autocatalysis and chemical amplification are characteristic properties of living systems, and they give rise to behaviors such as increased sensitivity, responsiveness, and self-replication. Here we report a synthetic system in which a unique form of compartmentalization leads to nonlinear, autocatalytic behavior. The compartment is a reversibly formed capsule in which a reagent is sequestered. Reaction products displace the reagent from the capsule into solution and the reaction rate is accelerated. The resulting self-regulation is sensitive to the highly selective molecular recognition properties of the capsule. 相似文献
115.
Andrei P Kozlov Yuri P Galachyants Ilya V Dukhovlinov Nickolai A Samusik Ancha V Baranova Dmitry E Polev Larisa L Krukovskaya 《Infectious agents and cancer》2006,1(1):8-10
Background
Earlier we suggested the concept of the positive evolutionary role of tumors. According to this concept, tumors provide conditions for the expression of evolutionarily new and/or sleeping genes in their cells. Thus, tumors are considered as evolutionary proving ground or reservoir of expression. To support this concept we have previously characterized in silico and experimentally a new class of human tumor-related transcribed sequences. 相似文献116.
Clinical characteristics of individuals with germline mutations in BRCA1 and BRCA2: analysis of 10,000 individuals. 总被引:16,自引:0,他引:16
Thomas S Frank Amie M Deffenbaugh Julia E Reid Mark Hulick Brian E Ward Beth Lingenfelter Kathi L Gumpper Thomas Scholl Sean V Tavtigian Dmitry R Pruss Gregory C Critchfield 《Journal of clinical oncology》2002,20(6):1480-1490
PURPOSE: To assess the characteristics that correlate best with the presence of mutations in BRCA1 and BRCA2 in individuals tested in a clinical setting. PATIENTS AND METHODS: The results of 10,000 consecutive gene sequence analyses performed to identify mutations anywhere in the BRCA1 and BRCA2 genes (7,461 analyses) or for three specific Ashkenazi Jewish founder mutations (2,539 analyses) were correlated with personal and family history of cancer, ancestry, invasive versus noninvasive breast neoplasia, and sex. RESULTS: Mutations were identified in 1,720 (17.2%) of the 10,000 individuals tested, including 968 (20%) of 4,843 women with breast cancer and 281 (34%) of 824 with ovarian cancer, and the prevalence of mutations was correlated with specific features of the personal and family histories of the individuals tested. Mutations were as prevalent in high-risk women of African (25 [19%] of 133) and other non-Ashkenazi ancestries as those of European ancestry (712 [16%] of 4379) and were significantly less prevalent in women diagnosed before 50 years of age with ductal carcinoma in situ than with invasive breast cancer (13% v 24%, P =.0007). Of the 74 mutations identified in individuals of Ashkenazi ancestry through full sequence analysis of both BRCA1 and BRCA2, 16 (21.6%) were nonfounder mutations, including seven in BRCA1 and nine in BRCA2. Twenty-one (28%) of 76 men with breast cancer carried mutations, of which more than one third occurred in BRCA1. CONCLUSION: Specific features of personal and family history can be used to assess the likelihood of identifying a mutation in BRCA1 or BRCA2 in individuals tested in a clinical setting. 相似文献
117.
Reperfusion-induced arrhythmias in rats and rabbits are highly temperature-dependent. When the rectal temperature of experimental animals was low, the effects of electroacupuncture at Jian Xi on reperfusion-induced arrhythmias could be observed. The arrhythmias shortened in rabbits, and more ventricular extrasystoles following reperfusion were seen in rats. It is suggested that electroacupuncture at Jian Xi can exert significant influence on reperfusion-induced arrhythmias. 相似文献
118.
Tinkelman D Nordyke RJ Isonaka S George D DesFosses K Nonikov D 《Journal of managed care pharmacy : JMCP》2005,11(1):25-32
OBJECTIVES: Chronic obstructive pulmonary disease (COPD) as a cause of disability with subsequent costs remains poorly recognized. The small, growing body of literature on COPD shows that it is one of the leading causes of missed work.greater than asthma or diabetes. However, much less is known about the impact of COPD on long-term disability (LTD). Because the health care burden for disabled, working-age patients will fall heavily on managed care organizations, better estimates of the economic and pharmacoeconomic costs of COPD are required. We seek to improve understanding of the burden of COPD on several national LTD programs. METHODS: We reviewed occupational health and disability literature and government statistics to determine how long-term, respiratory-related disability is addressed by disability pension programs in 8 developed countries (Canada, France, Germany, Italy, Japan, Spain, the United Kingdom, and the United States). We then applied respiratory-specific disability definitions to country-specific population and pension information to estimate the potential burden of COPD on LTD insurance programs in each country. RESULTS: Comprehensive, relevant data to evaluate respiratory-related disability are lacking. Of the study countries, only the United States has explicit respiratory specific criteria for disability eligibility, which are based solely on spirometry. We estimate that the total burden of COPD in the study countries may range from 5 billion dollars to as high as 25 billion dollars per year if all persons who met U.S. eligibility criteria for respiratory-related disability were granted compensation. CONCLUSION: The potential burden of COPD on LTD programs may be large. The lack of standard criteria for respiratory-related disability may lead to underrecognition of COPD's true potential impact. Further work is needed to develop consistent and cost-effective ways to measure the impact of COPD and to assist in disability determination for COPD patients. 相似文献
119.
120.
Kazakov DV Suster S LeBoit PE Calonje E Bisceglia M Kutzner H Rütten A Mentzel T Schaller J Zelger B Baltaci M Leivo I Rose C Fukunaga M Simpson RH Yang Y Carlson JA Cavazza A Hes O Mukensnabl P Vanecek T Fidalgo A Pizinger K Michal M 《The American journal of surgical pathology》2005,29(6):764-782
We present the largest series of mucinous carcinoma involving the skin, describing the histopathologic, immunohistochemical, electron microscopic, and cytogenetic findings. Our aim was fully to characterize the clinicopathologic spectrum and compare it with that seen in the breast. In addition, we wished to reevaluate the differential diagnostic criteria for distinguishing primary mucinous carcinomas from histologically similar neoplasms involving the skin secondarily, and study some aspects of their pathogenesis. We demonstrate that primary cutaneous mucinous carcinomas span a morphologic spectrum compatible to their mammary counterparts. Both pure and mixed types can be delineated morphologically, and some lesions have mucocele-like configurations. Most lesions seem to originate from in situ lesions that may represent, using mammary pathology terminology, ductal hyperplasia, atypical ductal hyperplasia, or ductal carcinoma in situ or a combination of the three. Inverse cell polarity appears to facilitate the progression of the changes similar to lesions in the breast. The presence of an in situ component defines the neoplasm as primary cutaneous, but its absence does not exclude the diagnosis; although for such neoplasms, full clinical assessment is essential. Mammary mucinous carcinoma involving the skin: all patients presented with lesions on chest wall, breast, axilla, and these locations can serve as clue to the breast origin. Microscopically, cutaneous lesions were of both pure and mixed type, and this correlated with the primary in the breast. Dirty necrosis was a constant histologic finding in intestine mucinous carcinomas involving the skin, and this feature may serve as a clue to an intestinal origin. 相似文献