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141.
Considering psychiatry as a medical discipline, a diagnosis identifying a disorder should lead to an effective therapy. Such presumed causality is the basis of evidence-based psychiatry. We examined the strengths and weaknesses of research onto the causality of relationship between diagnosis and therapy of major depressive disorder and suggest what could be done to strengthen eventual claims on causality. Four obstacles for a rational evidence-based psychiatry were recognised. First, current classification systems are scientifically nonfalsifiable. Second, cerebral processes are-at least to some extent-nondeterministic, i.e. they are random, stochastic and/or chaotic. Third, the vague or lack of relationship between therapeutic regimens and suspected pathogenesis. Fourth, the inadequacy of tools to diagnose and delineate a functional disorder. We suggest a strategy to identify diagnostic prototypes that are characterised by a limited number of parameters (symptoms, markers and other characteristics). A prototypical diagnosis that may either support or reject particular elements of current diagnostic systems. Nevertheless, one faces the possibility that psychiatry will remain a relatively weak evidence-based medical discipline. 相似文献
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144.
Afanas'ev SS Aleshkin VA Vorob'ev AA Feklisova LV Popov VF Nesvizhskiĭ IuV Meskina ER Afanas'ev MS Man'ko TN Rubal'skiĭ OV 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》2005,(6):94-99
The data contained in literature and obtained in our own investigations, aimed at the evaluation of the significance of interferon preparations for the correction of immunological disturbances are presented. A special place is given to the role of mild medicinal forms of interferon, the necessity of their use is grounded and good prospects for their inclusion into the complex therapy of infectious diseases are shown. 相似文献
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146.
Peculiarities of the genotype effect of cultivated and wild sunflower species on crossability indices and in vitro hybrid embryonic development have been investigated. It was shown that selection of initial material can considerably influence seed-setting and in vitro embryonic development in the cross group of cultivated sunflower with annual and perennial wild species. The range of plant hybrids obtained through somatic embryogenesis and induction of adventitious shoots was higher in comparison with direct growth of embryos in in vitro culture. 相似文献
147.
Severe acute respiratory syndrome coronavirus 3a protein is a viral structural protein 总被引:9,自引:0,他引:9
Ito N Mossel EC Narayanan K Popov VL Huang C Inoue T Peters CJ Makino S 《Journal of virology》2005,79(5):3182-3186
The present study showed the association of a severe acute respiratory syndrome coronavirus (SCoV) accessory protein, 3a, with plasma membrane and intracellular SCoV particles in infected cells. 3a protein appeared to undergo posttranslational modifications in infected cells and was incorporated into SCoV particles, establishing that 3a protein was a SCoV structural protein. 相似文献
148.
A. N. Vasil’eva K. S. Klopovskii A. S. Kovalev D. V. Lopaev Yu. A. Mankelevich N. A. Popov A. T. Rakhimov T. V. Rakhimova 《Plasma Physics Reports》2005,31(4):325-337
The production of O2(a1Δg) singlet oxygen in non-self-sustained discharges in pure oxygen and mixtures of oxygen with noble gases (Ar or He) was studied experimentally. It is shown that the energy efficiency of O2(a1Δg production can be optimized with respect to the reduced electric field E/N. It is shown that the optimal E/N values correspond to electron temperatures of 1.2–1.4 eV. At these E/N values, a decrease in the oxygen percentage in the mixture leads to an increase in the excitation rate of singlet oxygen because of the increase in the specific energy deposition per O2 molecule. The onset of discharge instabilities not only greatly reduces the energy efficiency of singlet oxygen production but also makes it impossible to achieve high energy deposition in a non-self-sustained discharge. A model of a non-self-sustained discharge in pure oxygen is developed. It is shown that good agreement between the experimental and computed results for a discharge in oxygen over a wide range of reduced electric fields can be achieved only by taking into account the ion component of the discharge current. The cross section for the electron-impact excitation of O2(a1Δg and the kinetic scheme of the discharge processes with the participation of singlet oxygen are verified by comparing the experimental and computed data on the energy efficiency of the production of O2(a1Δg and the dynamics of its concentration. It is shown that, in the dynamics of O2(a1Δg molecules in the discharge afterglow, an important role is played by their deexcitation in a three-body reaction with the participation of O(3P) atoms. At high energy depositions in a non-self-sustained discharge, this reaction can reduce the maximal attainable concentration of singlet oxygen. The effect of a hydrogen additive to an Ar: O2 mixture is analyzed based on the results obtained using the model developed. It is shown that, for actual electron beam current densities, a significant energy deposition in a non-self-sustained discharge in the mixtures under study can be achieved due to the high rate of electron detachment from negative ions. In this case, however, significant heating of the mixture can lead to a rapid quenching of O2(a1Δg molecules by atomic hydrogen. 相似文献
149.
Dubnovitsky AP Ravelli RB Popov AN Papageorgiou AC 《Protein science : a publication of the Protein Society》2005,14(6):1498-1507
The X-ray susceptibility of the lysine-pyridoxal-5'-phosphate Schiff base in Bacillus alcalophilus phosphoserine aminotransferase has been investigated using crystallographic data collected at 100 K to 1.3 A resolution, complemented by on-line spectroscopic studies. X-rays induce deprotonation of the internal aldimine, changes in the Schiff base conformation, displacement of the cofactor molecule, and disruption of the Schiff base linkage between pyridoxal-5'-phosphate and the Lys residue. Analysis of the "undamaged" structure reveals a significant chemical strain on the internal aldimine bond that leads to a pronounced geometrical distortion of the cofactor. However, upon crystal exposure to the X-rays, the strain and distortion are relaxed and eventually diminished when the total absorbed dose has exceeded 4.7 x 10(6) Ggamma. Our data provide new insights into the enzymatic activation of pyridoxal-5'-phosphate and suggest that special care should be taken while using macromolecular crystallography to study details in strained active sites. 相似文献
150.
Platikanov S Nikolov S Pavlova D Evstatieva L Popov S 《Zeitschrift für Naturforschung. C, Journal of biosciences》2005,60(7-8):591-599
This paper shows the changes of the volatile compounds from four Astragalus species at three phenological stages: leaf development, flowering and fructification, which might be connected with the plant defense. After GC/MS analyses of Astragalus glycyphyllos L., A. hamosus L., A. cicer L. and A. spruneri Boiss., different groups of volatile compounds were found: hydrocarbons, alcohols, aldehydes and ketones, esters, terpenes, chlorinated compounds, etc. Identified volatiles were used for a cluster analysis in order to make chemotaxonomic conclusions for these evolutionary different species. 相似文献