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1.
Manganese dioxide is shown to be the catalyst of oxygen evolution at the oxidation of water by the one-electron oxidant Ru(bpy)33+ in neutral and slightly acidic media. Catalytic activity of MnO2 depends on the method of preparation, the most active samples being those consisting of the smallest particles, i.e., having the largest surface-to-volume ratio. Ru(bpy)33+ was found to be formed at the irradiation of Ru(bpy)32+ solutions by visible light (λ = 436 nm) in the presence of such acceptors as Ce(IV), Hg(II), and Mn(IV) pyrophosphate. Continuous O2 evolution from water is observed when the system Mn(IV) pyrophosphate plus Ru(bpy)32+ plus MnO2 is irradiated by visible light. The system is discussed in connection with the active center of photosystem II of plant photosynthesis. 相似文献
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T V Bakalkin GYaYakovleva L A Nikitina N V Korobov V A Vinogradov M I Titov 《Biochemical and biophysical research communications》1983,117(3):718-724
Binding sites with high affinity for [3H]naloxone, but not for [3H]morphine and [3H] (D-Ala2, D-Leu5) enkephalin, have been found in membranes of Bufo viridis oocytes. The binding is reversible and saturable. Bound [3H]naloxone is easily displaced both by unlabeled naloxone and bremazocine, much worse by morphine and SKF 10,047; (D-Ala2, D-Leu5) enkephalin and beta-endorphin practically fail to displace [3H]naloxone. Scatchard analysis is consistent with the existence of two classes of binding sites with Kd 15 nM and 10(3) nM. The number of binding sites with high affinity for naloxone is 16 pmol/mg protein of homogenized oocytes which is 20-50-fold higher than in, toad or rat brain. Oocyte extract displaces [3H]naloxone bound with oocytes' membranes and inhibits electrically evoked contractions of the rabbit vas deferens. This inhibition is reversed by naloxone. It is suggested that compounds similar to opiate kappa-agonists exist in oocytes. It cannot be ruled out that they participate via specific receptors in the regulation of oocyte maturation and egg development. 相似文献
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Activation of a nuclease by pppA2'p5'A2'p5'A in intact cells. 总被引:1,自引:0,他引:1
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Na+, K+, H+ and Cl- permeability properties of rabbit skeletal muscle sarcolemmal vesicles 总被引:1,自引:0,他引:1
The ion permeability properties of rabbit skeletal muscle sarcolemmal vesicles were investigated by means of radioisotope flux, membrane potential, and light-scattering measurements. An enriched sarcolemmal fraction was obtained from the 22-27% region of sucrose gradients after isopycnic centrifugation. The presence of contaminating sarcoplasmic reticulum was assessed with the use of a purified sarcoplasmic reticulum vesicle fraction. 22Na+, 86Rb+, 36Cl-, and [3H]sucrose flux measurements indicated that the sarcolemmal fraction possessed isotope spaces ranging between 1.5 and 4 microliters/mg protein. Membrane potential measurements using the voltage-sensitive fluorescent probe 3,3'-dipentyl-2,2'-oxadicarbocyanine iodide (diO-C5-(3)) indicated that sarcolemmal vesicles were impermeable to H+ and Na+ but that 10-15% of the vesicles were permeable to K+. Light-scattering measurements indicated a small fraction of sarcolemmal vesicles were permeable to both K+ and Cl-. Whether the low permeability of sarcolemmal vesicles to Na+, K+, and Cl- is the result of a low concentration of ion channels or the inactivation of these channels during isolation is at present uncertain. 相似文献
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The authors visited Soviet medical institutions as part of a USA-USSR Professional Exchange Program sponsored by the Fogarty International Center. The primary purpose of this visit was to obtain a general view of the Soviet use and care of laboratory animals in biomedical research and to lay a foundation for a continuing exchange of information and models. 相似文献
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B A Lapin 《Journal of medical primatology》1983,12(3):124-128
A short historical survey and a more extensive presentation on the present developments of research using primates in the USSR are given. 相似文献
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《Microbes and infection / Institut Pasteur》2021,23(8):104838
The present contribution analyses sanitary theatrical performances as a means of anti-tuberculosis propaganda in the early Soviet Union. Starting in the 1920s, sanitary theatrical performances were demonstrated in open-air theatres and clubhouses for workers and farmers. Since 1925, the newly founded Moscow Theatre for Sanitary Culture centrally managed the theatrical hygiene propaganda. It became a role model for other theatres of hygienic enlightenment and numerous sanitary amateur stages. Their anti-tuberculosis repertoire ranged from the so-called “mock trials” where a person or even Koch's bacillus must stand trial for the spreading of tuberculosis, to “living newspapers” which used entertainment elements such as music or acrobatics to provide a mass audience with the hygiene knowledge. The contribution describes in which images, figures and actions knowledge about tuberculosis was presented on stage, which genre traditions and communicative instruments were used and which changing political implications those performances were based on. To achieve this goal, the archive sources, selected texts of theatrical performances, reports and reviews in daily press have been evaluated. 相似文献
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DIANA PUSHKINA 《Mammal Review》2007,37(3):224-245
- 1 The Palaeoloxodon antiquus large‐mammal assemblage was typical of the late middle and late Pleistocene interglacials in Europe. This review examines the assemblage's origins, dispersal and cohesiveness in Eurasia.
- 2 During the more climatically equable middle‐Pleistocene periods, the Palaeoloxodon assemblage (or closely related) species occurred across central Eurasia almost simultaneously. In Central and Western Europe, these species responded to climatic changes together as an unvarying interglacial assemblage, whereas in Eastern Europe and Siberia, they occurred in diverging assemblages. The boundary of the Palaeoloxodon assemblage can be drawn roughly from Poland to Romania.
- 3 In Central and Western Europe this interglacial assemblage last occurred during the Eemian. During this period many of the Palaeoloxodon assemblage species may also have co‐occurred in south‐eastern Europe and, except for Bubalus murrensis and Hippopotamus amphibius, further eastwards. The extinct species of the Palaeoloxodon assemblage disappeared in Siberia and Central Asia prior to Europe and the Caucasus whereas the extant species were already present in their modern distribution areas.
- 4 A quantitative study of faunal associations across Eurasia, following much‐needed comprehensive systematic reviews, would further elucidate the patterns of faunal change associated with local and global climatic changes during the middle to late Pleistocene.
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Percottus glehni is a new colonizer in the ichthyofauna of Lake Glubokoe. Recently, this species, established in the European part of the
USSR nearly 30 years ago, has become common in the lakes and ponds located 3–5 km from Lake Glubokoe. In Lake Glubokoe it
keeps mainly to water thyme (Elodea) in shallow water with individuals up to 7 cm in size being predominant. Apparently, these fishes are not abundant due to
strong predation pressure from larger predators. 相似文献
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Internal structure of Stenopopanoceras mirabilePopow, Parapopanoceras sp., P. mediumMcLearn, P. janaense (Popow), P. paniculatumPopow, P. asseretoiDagys & Ermakova, Indigirites krugiPopow, Nathorstites mcconnelli (Whiteaves), N. gibbosusStolley, N. lenticularis (Whiteaves), N. argatassensis (Popow) is described and also ontogenetic development of species I. krugiPopow and N. mcconnelli (Whiteaves) originating from middle triassic deposits of northern part of Middle Siberia, north-eastern part of the USSR and Svalbard is given. For the species mentioned above data is given on the position of siphuncle, shape and dimensions of protoconch, caecum, ammonitella, the angle of primary varix, structure of septal necks and the nature of their change in the course of ontogeny. Significance of these signs for taxonomy and phylogeny of triassic ammonoidea is analysed. Intergeneric difference of Stenopopanoceras and Parapopanoceras is established according to the position of siphuncle on the first whorl of the shell. On the basis of the analysis of internal structure and ontogenetic development of suture line and morphological signs Indigirites is considered to belong to the family Hungaritidae (subfamily Longobarditinae). Phylogenetic patterns of the ammonoidea species described are discussed. 相似文献
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Estate M. Sokhadze Ph.D. Mark B. Shtark 《Applied psychophysiology and biofeedback》1991,16(3):253-260
This paper describes the history of biofeedback research and application in the USSR. The approach of USSR scientists to the study of basic mechanisms of biofeedback and the status of clinical applications of biofeedback in the Soviet Union are described. Trends in the publication of biofeedback-related papers in Russian are presented, and the present state of the art described. Promising prospects for biofeedback research and application are discussed. 相似文献
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N. P. Lukashenko A. G. Vol'fson V. A. Istomin V. Yn. Chernov 《International journal for parasitology》1971,1(3-4):287-296
During an examination, for trichinellosis, of 1489 mammals of 12 different species, in the territory of Chukotka National district (regions of Anadyr', Bering, Iul'tin, Chaun and Chukotka) and in the region of North-Even of Magadan province, Trichinella larvae were detected in 236 (16·4%) of these animals from 6 of the species: in 109 (44·8%) of the blue polar foxes kept in cages, in 12 (15·8%) of the silver-black foxes kept in cages, in 84 (18·2%) of the white polar foxes, in 17 (17·5%) of the common foxes, in 13 (12·1%) of the dogs and in the one European bear examined. Trichinella larvae were not found in 190 marine mammals examined: 178 ringed seals, 7 whales, 4 walruses, and 1 bearded seal, nor in the 8 Siberian squirrels and 159 domestic pigs examined. The high incidence of Trichinella infection amongst blue polar foxes and silver-black foxes on fur-animal farms in Chukotka, where the food ration of these animals is predominately the flesh of marine mammals (walruses and other pinnipeds), suggests that marine mammals may constitute one of the sources of infection to caged animals. In Chukotka, as in other regions of the Extreme North and North-East, the circulation of trichinae in nature may occur between two ecologically different groups of animals: terrestial and marine mammals. A wide distribution of trichinellosis among animals in nature, or kept in cages and among dogs in Chukotka National district and in the North-Even region of Magadan province provides a constant threat of infection to man. Thus the flesh and sub-products of potential hosts of trichinae (including dogs, fur animals, European and polar bears, marine mammals, etc.) should undergo thorough trichinelloscopy examination before being consumed by man. The flesh of sea mammals should be examined for trichinellosis before being used as food for animals; the presence of trichinae in it requires its sterilization. 相似文献
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Vladimir G. Klikushin 《Geobios》1982,15(6):811-843
The theca and the columnals of twenty-two lateCretaceous species of the genus Bourgueticrinus (including two new species), of one species of the genus Democrinus, of four species of the genus Conocrinus (including one new species) and of one species of the genus Paleobathycrinus known from USSR are figured and shortly described. Biometric reconstructions of stems for B. aequalis, B. bellus, B. danicus, B. fischeri and C. tauricus nov. sp. are given. A new index is used to suggest the relative flexibility of stem. Decrease in dimension and flexibility of the arms in several species take place simultaneously with an increase of stem flexibility. This fact seems to be closely related to environmental changes. 相似文献
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Dr. Edward B. Blanchard Guy C. McCoy Robert J. McCaffrey David A. Wittrock Alison Musso Marta Berger Tatyana A. Aivasyan Viktor V. Khramelashvili Boris B. Salenko 《Applied psychophysiology and biofeedback》1988,13(1):25-38
Cardiovascular reactivity (heart rate, systolic, and diastolic BP) to mental arithmetic and cold pressor were measured before and after treatment as part of the cross-cultural (USSR and USA) evaluation of thermal biofeedback and autogenic training (in comparison with self-relaxation) as treatments for mild hypertension in unmedicated males. There were no statistically reliable decreases in cardiovascular reactivity from before to after treatment. However, downward shifts in basal levels of systolic and diastolic BP at post-treatment led treated patients to have lower stress-induced levels of BP.The American portion of this research was supported by a grant from the NHLBI, HL-31189. We express appreciation to officials at the USSR Cardiology Research Center, Academician Igor Shkhvatsabaya, and Professor Vadim Zaitsev for their support, as well as to Dr. Steve Weiss, of NHLBI, for his instigation of this research. 相似文献
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