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991.
An overview of research seeking and studying the potential low temperature sensors in plants is provided. It was shown that the number of potential candidates for low temperature sensors is quite wide and includes both individual intracellular structures and substances: membranes, cytoskeletal elements, chromatin, phytochromes, DNA, RNA, specific proteins, and sugars. It was noted that, depending on the mode of thermal exposure (intensity, cooling rate, duration, etc.), the leading role of temperature sensors may be played by different structures or substances. Apparently, this variety allows plants to respond to cold more flexibly and appropriately.  相似文献   
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The antigen-antibody interaction occurring previous to the triggering of the immunological response is analyzed as a relational process in terms of lattices. Accordingly, this process is expressed as a lattice belonging to a pseudo-Boolean algebraic variety. The Heyting arrow operation, which appears in this kind of algebra, is used to analyze behaviors between non-comparable biological states expressed by the lattice. The resulting states coming from the arrows are connected with the influence of increasing and decreasing energies involved in the linking process.  相似文献   
995.
The effects of β-endorphin under the conditions of naloxone hydrochloride blockade of opiate receptors, as well as the effects of the selective agonists of μ-and δ-receptors DAGO and DADLE and the effects of melanocyte-potentiating factor (MPF), on the in vitro proliferative response of lymphocytes were studied. The dose-effect dependence indicated stimulating effects of β-endorphin, DAGO, and DADLE on the proliferative response in the presence of phytohemagglutinin (PHA). The tetrapeptide MPF, which is the C-terminal sequence of β-endorphin, had almost no effect on the proliferative activity of lymphocytes. β-Endorphin, naloxone, and the μ-and δ-receptor selective agonists enhanced the proliferative response of lymphocytes in an unfractionated cell culture, whereas β-endorphin, naloxone, and DAGO suppressed the proliferative activity of lymphocytes in the mononuclear fraction purified of monocytes. In both cases, the naloxone blockade of opiate receptors enhanced rather than eliminated the β-endorphin effect.  相似文献   
996.
Delusions are currently characterised as false beliefs produced by incorrect inference about external reality (DSM IV). This inferential conception has proved hard to link to explanations pitched at the level of neurobiology and neuroanatomy. This paper provides that link via a neurocomputational theory, based on evolutionary considerations, of the role of the prefrontal cortex in regulating offline cognition. When pathologically neuromodulated the prefrontal cortex produces hypersalient experiences which monopolise offline cognition. The result is characteristic psychotic experiences and patterns of thought. This bottom-up account uses neural network theory to integrate recent theories of the role of dopamine in delusion with the insights of inferential accounts. It also provides a general model for evolutionary psychiatry which avoids theoretical problems imported from evolutionary psychology.  相似文献   
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Summary A child with cri-du-chat syndrome, 46,XY,5p-, was born to a mother who had two normal children and two abortuses. The mother was shown to carry a balanced translocation. Giemsa and fluorescent banding demonstrate the exact location of the translocated segment. The deleted short arm of chromosome number 5 was shown to be attached to the long arm of chromosome number 11.
Zusammenfassung Ein Kind mit Cri-du-chat Syndrom und Karyotyp 46,XY,5p- wurde von einer Mutter geboren, die zuvor zwei gesunde Kinder und zwei Aborte gehabt hatte. Bei der Mutter wurde eine balancierte Translokation nachgewiesen; Chiemsa- und Fluorescens-Bandenmuster zeigten die genaue Lokalisation des translozierten Segmentes: Der deletierte kurze Arm des Chromosoms Nr.5 war an den langen Arm vom Chromosom Nr. 11 angeheftet.


We are indeed indebted to Dr. G. R. Hennigar for facilities and Dr. C. D. Barnett for financial assistance.  相似文献   
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