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931.
Motivated by a question of W. Rautenberg, we prove that any matrix that is term-equivalent to the well-known nonfinitely based matrix of A. Wroski is itself also nonfinitely based. 相似文献
932.
BACKGROUND: Brain morphology and physiological measures in schizophrenia have yielded inconsistent results. This may be due in part to difficulties in ascertaining precisely to what degree each measure deviates from its genetically and environmentally determined potential level. We attempted to surmount this problem in a paradigm involving monozygotic twin pair discordant for schizophrenia. In this paradigm, the difference score and reaction time between the unaffected member and affected member of a twin pair should represent the degree of pathologic involvement irrespective of actual level. METHOD: We investigated, using fMRI, the neural substrate underlying encoding and retrieval of aversive and neutral IAPS pictures. RESULTS: An ANOVA on reaction time (RT) between schizophrenia patient (J) and normal sister (D) significant difference, (F = 5.2, p < or = .02) for J had less RT than D. Conversely, the ANOVA for the correct pictures retrieved was insignificant (F = 1.8, p < or = .2). When the brain activity associated with the encoding and retrieval of the aversive pictures was subtracted (J-D and D-J) from that associated with the neutral ones, significant loci of activation were found. During encoding: for J-D the right fusiform gyrus was significantly activated (p < .0001) and for D-J the orbitofrontal cortex was significantly activated (p < .05). During retrieval: for J-D the right anterior cingulate (p < .0001) was activated and the dorsolateral prefrontal cortex (p < .002). For D-J only the cerebellum showed activation (p < .0001). CONCLUSION: Results indicated subtle attenuations in some aspects of memory, thus providing another evidence for cognitive markers of a genetic component in schizophrenia. New approaches in neuropsychiatry-based on genetic methodologies should further define the cerebral physiology responsible for schizophrenia. 相似文献
933.
Puzyński S 《Science and engineering ethics》2004,10(1):135-142
The paper presents major ethical, legal and methodological problems related to the use of placebo in mental disorders, especially
in depression. It is pointed out that although authoritative groups of experts and numerous publications in the field of psychopharmacology
indicate advisability of the double blind design with placebo in clinical trials of antidepressants, in recent years there
have been more and more voices questioning legitimacy of this method. Objections of an ethical nature are raised, and reliability
of this approach is put into doubt from the methodological viewpoint. These issues are discussed in more detail in the paper.
Available alternative solutions should be implemented in psychotropic drug studies. The author shares these objections and
doubts of an ethical nature, and believes that the placebo procedure is not a necessity in clinical trials of antidepressants.
An earlier version of this paper was presented at an international conference, “Placebo: Its Action and Place in Health Research
Today,” held in Warsaw, Poland on 12–13 April, 2003. 相似文献
934.
Baillargeon R 《Developmental science》2004,7(4):391-414
Research over the past 20 years has revealed that even very young infants possess expectations about physical events, and that these expectations undergo significant developments during the first year of life. In this article, I first review some of this research, focusing on infants' expectations about occlusion, containment, and covering events, all of which involve hidden objects. Next, I present an account of infants' physical reasoning that integrates these various findings, and describe new experiments that test predictions from this account. Finally, because all of the research I discuss uses the violation-of-expectation method, I address recent concerns about this method and summarize new findings that help alleviate these concerns. 相似文献
935.
An experiment was conducted to investigate people’s ability to vary a response criterion strategically, in a recognition memory task, as a function of the length of time given to process the test stimuli (from 100 to 1,500 msec). The experiment used the response signal procedure, in which the participants responded after a signal that came at a variable time delay from stimulus onset. The proportion of new versus old test items was varied systematically with the time of the response signal, with the proportion of new test items rising, falling, or staying constant at later signals. It was found that the participants’ response biases changed adaptively, becoming more conservative at later signals in the rising condition, becoming less conservative in the falling condition, and not changing significantly in the constant condition. Theoretical and methodological implications for recognition memory research are discussed. 相似文献
936.
The activation of cAMP response element-binding protein (CREB) after a learning experience is a common feature in the formation of several associative memories. We recently demonstrated that the increase in the hippocampal phosphorylated CREB (pCREB) levels 1 h after a short exploration of an open field (OF) was associated to detection of spatial novelty and was not related to the memory formation of habituation in this non-associative learning paradigm. Moreover, after a long training of three OF sessions, hippocampal pCREB levels were below to that observed in control rats. The present results show that such decrease does not correlate with memory retrieval or improvement in long-term memory of habituation. Instead, it is associated with the familiarity to the arena. Our experiments revealed that the relevant variable to induce CREB deactivation was the prolonged exploration of the arena (30 min). A 15 min OF exploration was ineffective. Furthermore, the last 5 min period of a prolonged exploration was crucial to change CREB phosphorylation state: when exploration took place in a novel arena the level of pCREB increased; in contrast, when it was performed in the familiar OF, pCREB levels decreased. Taken as a whole, our results suggest that CREB phosphorylation state in the hippocampus switches in response to exposure to a novel or to a familiar spatial environment. 相似文献
937.
Van Steendam G Dinnyés A Mallet J Meloni R Casabona CR González JG Kure J Szathmáry E Vorstenbosch J Molnár P Edbrooke D Sándor J Oberfrank F Cole-Turner R Hargittai I Littig B Ladikas M Mordini E Roosendaal HE Salvi M Gulyás B Malpede D 《Science and engineering ethics》2006,12(4):731-793
This paper reports on the meeting of the Sounding Board of the EU Reprogenetics Project that was held in Budapest, Hungary, 6-9 November 2005. The Reprogenetics Project runs from 2004 until 2007 and has a brief to study the ethical aspects of human reproductive cloning and germline gene therapy. Discussions during The Budapest Meeting are reported in depth in this paper as well as the initiatives to involve the participating groups and others in ongoing collaborations with the goal of forming an integrated network of European resources in the fields of ethics of science. 相似文献
938.
Switula D 《Science and engineering ethics》2006,12(1):147-156
Quality in clinical research may be defined as compliance with requirements together with credibility and reliability of the
data obtained. Sponsors usually apply Quality Management Systems (QMS) to ensure, control, maintain, and improve quality.
These systems encompass several preventive measures, tools, and controls. Standard QMS applied by clinical research sponsors
may be based on ISO 9000.
An earlier version of the paper was presented at the 6th International Bioethics Conference on the subject of ‘The Responsible
Conduct of Basic and Clinical Research’, held in Warsaw, Poland, 3–4 June 2005. 相似文献
939.
Pastell M Aisla AM Hautala M Poikalainen V Praks J Veermäe I Ahokas J 《Behavior research methods》2006,38(3):479-486
We have worked on automatically measuring the behavior of dairy cows during automatic milking. A milking robot offers a unique
possibility for a dynamic measurement of physical data. Four strain gauge scales were installed into a milking robot in order
to measure the weight of each leg separately, and a laser distance sensor was placed next to the robot in order to measure
the radial movement of the cow’s body surface. The data were collected into a PC. Three video cameras were installed to observe
the system, and the data were recorded digitally. From the data, the dynamic weight or load of each leg and the respiration
rate of a cow could be measured. Different stages of milking were observed, and the changes in behavior during milking were
analyzed. The acquired information could be used to judge a cow’s restlessness and welfare—for example, leg health and stress. 相似文献
940.
Wietrzych M Meziane H Sutter A Ghyselinck N Chapman PF Chambon P Krezel W 《Learning & memory (Cold Spring Harbor, N.Y.)》2005,12(3):318-326
Retinoid signaling has been recently shown to be required for mnemonic functions in rodents. To dissect the behavioral and molecular mechanisms involved in this requirement, we have analyzed the spatial and recognition working memory in mice carrying null mutations of retinoid receptors RARbeta and RXRgamma. Double mutants appeared deficient in spatial working memory as tested in spontaneous alternation in the Y-maze and delayed nonmatch to place (DNMTP) test in the T-maze. These mutant mice did acquire, however, spatial place reference or right/left discrimination tasks in the T-maze set-up, indicating that basic sensorimotor functions, spatial orientation, and motivational factors are unlikely to account for deficits in working memory-sensitive tasks. Double-mutant mice were also deficient in novel object recognition at intermediate, but not short delays. RXRgamma appeared to be the functionally predominant receptor in modulation of the working memory, as RXRgamma, but not RARbeta single null mutant mice exhibited deficits similar to those observed in the double mutants. The mechanism of this modulation is potentially related to functions of RXRgamma in frontal and perirhinal cortex, structures in which we detected RXRgamma expression and which are functionally implicated in working memory processes. 相似文献