Effect of thiamine on auditory evoked potentials of the guinea pig

Application of thiamine (1 X 10(-11)-1 X 10(-3) mol/l) on the membrane of cochlear round window increased the amplitude and decreased the latency of the auditory nerve action potential, waves I and II of brainstem auditory-evoked electrical potentials in response to acoustic clicks of different intensity. The mechanism of thiamine action on auditory-evoked electric potentials is discussed.     

An estimate of phylogenetic relationships among culicine mosquitoes using a restriction map of the rDNA cistron

Restriction maps of the rDNA cistron of twelve species of mosquitoes in six genera of the subfamily Culicinae were constructed using eight 6 bp recognition restriction enzymes. Anopheles albimanus was used as an outgroup. The size of the rDNA cistron ranged from 8.5 kb in Aedes katherinensis to 12.9 kb in Ae. polynesiensis. A total of twenty-six sites were scored; eighteen were polymorphic among ingroup taxa. The proportion of polymorphic nucleotide sites (Pnuc) was 0.059 and the heterozygosity per nucleotide site (Hnuc) was 0.028. Wagner and Fitch Parsimony, Dollo Parsimony and Nei-Li distance/neighbour-joining methods were used to construct phylogenetic trees. The rDNA RFLP dataset did not provide a well-supported phylogeny among culicine taxa. The RFLP phylogenies are incongruent with the morphology character based and molecular phylogenies and derived relationships did not correspond with current taxonomic classifications. The lack of resolution was due to homoplasy arising from frequent independent loss or gain of restriction sites among unrelated taxa.     

Informational technologies in medical support to an interplanetary mission crew]

Plans to send humans to Mars dictate revision of the whole crew medical support system. Autonomy of the mission will extend crew responsibilities for all dimensions of medical support. The article compares and contrasts medical support of crews on orbital and interplanetary missions, and considers the place and functionality of medical informational technologies in a mission to Mars.     

Experience in the organization of heart surgery services to patients with disorders of heart rhythm and conduction in large cities

The article generalizes 17-year experience in the organization of surgical service for patients with disturbed rhythm and conductivity of the heart in Leningrad and the northwest region of the USSR. The work of the city center of surgery of arrhythmias is analysed. Prospective calculations were made. Basically new approaches to determining the regular number of persons on the staff and the number and type or operative interventions are suggested.