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1.
Clinical, bacteriological, serological and epidemiological studies of ozena morbidity among the population of Minsk were carried out in 1970-1980. On January 1, 1981, the ozena morbidity rate among the inhabitants of Minsk was 26.72%. Ozena was found to affect mainly children and women. A wide spread of the family foci of this disease (31.68%) was revealed. The results of this study indicate that the source of K. ozaenae is a sick person who begins to excrete the bacteria in the prodromal period of the disease and may continue to excrete them for many years. The transfer of K. ozaenae occurs probably by droplet or contact infection. The droplet infection is less active in the absence of symptoms (coughing, sneezing) facilitating excretion of the infective agent into the air and in cases of the low susceptibility of persons to ozena. The main measures for controlling ozena are the timely detection and sanitation of the sources of ozena, as well as the current disinfection of the infection foci in apartments.  相似文献   
2.
The effect of mouse anti-mosquito antibodies, present in the bloodmeal, on the infectivity of Plasmodium berghei Vincke to Anopheles farauti Laveran was investigated. Significantly fewer oocysts developed in mosquitoes feeding on mice immunized with sugar-fed mosquito midgut antigens than in mosquitoes feeding on control mice. Mosquitoes feeding on mice immunized with the midgut antigens derived from sugar-fed mosquitoes also showed reduced mortality and had lower infection rates than those fed on unimmunized mice. Blood-fed midgut antigen was less effective in producing these effects than sugar-fed midgut antigen.  相似文献   
3.
Molecular biology of wound-inducible proteinase inhibitors in plants   总被引:4,自引:4,他引:0  
Abstract. The techniques of molecular biology are being employed to investigate at the gene level the systemically mediated, wound-induced accumulation of two defensive proteinase inhibitor proteins in plant leaves. These techniques have added a new dimension to biochemical and physiological studies already underway to understand the mechanism of induction by wounding. The acquisition of cDNAs from the RNAs coding for the two inhibitors facilitated studies of mRNA synthesis in leaves in response to wounding, and provided probes to obtain wound-inducible proteinase inhibitor genes from tomato ( Lycopersicon esculentum ) and potato (Solarium tuberosum) genomes. Successful transformations of tobacco plants with fused genes, containing the 5' and 3' regions of the inhibitor genes with the open reading frame of the chloramphenicol acelyltransferase ( cat ) gene, have provided a wound-inducible chloramphenicol acetyltransferase (CATase) activity with which to seek cis- and transacting elements that regulate wound-inducibility to help to understand the interaction of cytoplasmic and nuclear components of the intracellular communication systems that activate the proteinase inhibitor genes in response to wounding by insect pests.  相似文献   
4.
V G Lebedev 《Radiobiologiia》1991,31(4):510-514
Prodigiozan injected to long-term cultures of mouse bone marrow 24 h before irradiation increased CFUs and CFU-GM number and colony-stimulating factor (CSF) level by the time of delivery of ionizing radiation. As early as 60 min following irradiation of bone marrow structures with a dose of 2 Gy the number of CFUs and CFU-GM decreased considerably, and from day 3 on after irradiation the indices under study were gradually restored. By day 14 the cultures preinjected with prodigiozan exhibited higher recovery levels. The decrease in the number of precursor cells 60 min after irradiation was accompanied by a drastic increase in the CSF content of cultures; the CSF release in cultures protected with prodigiozan was more moderate than in the irradiated controls.  相似文献   
5.
The alkylating derivatives of four individual diastereomers of the oligonucleotide [dTp(Et)]3dTpU and two individual diastereomers of oligonucleotide [dTp(Et)dTp]4 have been synthesized. The reagents with the phosphorus atoms in the enantiomeric p" configuration are shown to be more efficient in reacting with poly(dA) and with nucleic acids in Krebs-2 ascites carcinoma cells compared to those with the phosphorus atoms in the p' configuration.  相似文献   
6.
Relationship between eye ability to perceive smooth motion under stroboscopic stimulation on forward motion (from which stationary positions of the object) in the plane perpendicular to the look line was found. For diagnostics and occupational selection it is suggested to carry out stimulation in several directions thus obtaining additional information about the visual system of the person under test.  相似文献   
7.
A study was made of the effectiveness of a new class of radioprotective agents, polypeptides, obtained from zootoxins of scorpion, tarantula, Lathrodectes tredecimguttatus, and bee under conditions of a short-term and long-term irradiation. The peptide fraction of the scorpion venom, butoxin, was most radioprotective: it provided 65% survival after LD98/30. Butoxin exerted a stimulatory effect on the hypophysis-adrenal system and haemopoiesis of intact and irradiated animals.  相似文献   
8.
Changes in the charge of sarcoplasmic reticulum (SR) vesicles are studied using lipophilic ions, which are adsorbed by the membrane phase. Upon addition of MgATP, phenyldicarbaundecaborane (PCB-) and tetraphenylboron (TPB-) are taken up by the SR vesicles, while tetraphenylphosphonium (TPP+) is released into the water phase. The PCB- uptake occurs as well under conditions when SR membrane is shunted by high Cl- concentration. MgATP induces minor additional binding of PCB- in the presence of oxalate and it is followed by release of the lipophilic anion from the vesicles. EGTA partly reverses the ATP effect, and calcium ionophore A23187 plus EGTA reverses it completely. Vesicles that were preliminarily loaded by Ca2+ demonstrated higher passive and lower ATP-dependent PCB- binding. Activation of isolated Ca2+-ATPase in the presence of 0.1 mM EGTA results in PCB- release into the medium and additional TPP+ binding to the enzyme. We suggest that the redistribution of the lipophilic ions between the water phase and SR membrane reflects charge changes in Ca2+-binding sites inside both SR vesicles and Ca2+-ATPase molecules in the course of Ca2+ translocation.  相似文献   
9.
10.
Antidromic discharges and spontaneous activity of single sympathetic preganglionic neurons in the lateral horns of the second lumbar segment of the spinal cord were recorded extracellularly in cats anesthetized with a mixture of chloralose and pentobarbital. A new technique used to identify antidromic discharges of sympathetic preganglionic neurons is described and the characteristics of discharges and sites where they were recorded are investigated. Changes in the frequency of spontaneous discharges of most neurons were shown to be connected with different types of fluctuation of the arterial pressure. Absence of functional specialization of the sympathetic preganglionic neurons is postulated.I. P. Pavlov Institute of Physiology, Academy of Sciences of the USSR, Leningrad. Translated from Neirofiziologiya, Vol.6, No.3, pp.295–303, May–June, 1974.  相似文献   
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