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61.
62.
A procedure for investigating the patellar reflex is described for isometric conditions when the position of the shin relative to the thigh is rigidly fixed by a special device. The sensors of the device record the development of the moment of force in each knee joint separately. The results obtained with an electromyogram and a mechanogram are compared.  相似文献   
63.
The present work demonstrates that the injection of cysteine hydrochloride, a reducing agent, into animals has a pronounced effect on the character of immune response to proteinaceous antigen (bovine serum albumin): the formation of antibodies is enhanced, the synthesis of IgM is prevented from being changed over to the synthesis of IgG, the time of the circulation of free antigen is reduced and the time of their circulation in the blood is increased.  相似文献   
64.
Plasma Physics Reports - When developing the stationary fusion reactor, an unresolved issue is the design of its intra-chamber plasma-facing elements. It has now become obvious that among the...  相似文献   
65.
66.
A series of new fine-tunable monodentate phosphite and phosphoramidite ligands based on carboranes have been synthesized and used for asymmetric Rh-catalyzed hydrogenation of prochiral olefins with the result of up to 99.8% ee. Dependence of the enantioselectivity on the electron-withdrawing or electron-donating properties of the carboranyl substituent has been studied.  相似文献   
67.
Mechanical and electrical properties of a synthetic polyelectrolyte hydrogel considered as a model of the cytoskeletal gel were studied. Hydrogels were synthesized from polymethacrylic acid by radical polymerization in aqueous solution. The electrical charge was introduced into the gel network by partial neutralization of monomer acids with magnesium hydroxide. Through the use of a motor, triangular longitudinal (axial) deformations were applied to gel samples. Simultaneously, the electrochemical (Donnan) potential of the gel was measured using conventional microelectrodes. We found that: (1) the Young modulus of the gel is 0.53 kPa; (2) at a given deformation velocity, the extent of gel deformation closely correlates with the gel potential; and (3) at the same level of gel deformation, the lower the deformation velocity, the higher the relative change of gel potential. These findings show a striking similarity to the data obtained in living cells, particularly in cardiac myocytes. A hypothesis involving the deformation-induced solvent migration from the gel to the surrounding solution is considered. It is concluded that the physicochemical features of the cytoskeletal gel may play a role in determining the mechanoelectric properties of excited cells.  相似文献   
68.
Results of experiments on proton acceleration from aluminum foils and organic films irradiated by laser pulses with intensities of up to 2 × 1019 W/cm2 are presented. To prevent thin targets from destruction by the superluminescence prepulse, a fast light shutter based on a Pockels cell was introduced in the amplifying system of the SOKOL-P facility. As a result, the energy contrast with respect to the superluminescence prepulse increased to 4 × 106, which made it possible to carry out experiments on the irradiation of targets with thicknesses less than 100 nm. It is found that the target material insignificantly affects the yield of accelerated protons.  相似文献   
69.
Analyses of allozyme (18 loci) and partial mitochondrial DNA (mtDNA) sequences (1295 bp, 16S rRNA) support the classification of phoxinin minnows from the northern Far East into 2 genera of 8 species: Phoxinus phoxinus, Rhynchocypris oxycephalus, R. perenurus, R. czekanowskii, R. kumgangensis, R. semotilus, R. lagowskii and R. sp. (bergi ?). Although R. lagowskii from Japan and the Amur basin and R. sp. from Vladivostok region to Korea have been classified into a single species by many authors as R. lagowskii, they form separate clusters in both analyses, suggesting different specific status. Some R. oxycephalus and R. perenurus had the mtDNA haplotypes of R. lagowskii and R. czekanowskii, respectively, which probably indicates that local introgression of mtDNA occurred through inter-specific hybridization. Rhynchocypris forms a monophyletic cluster with dace genera Tribolodon and Pseudaspius, not with Phoxinus. Eurasian and American Phoxinus are suggested to be paraphyletic.  相似文献   
70.
Electron microscopic study of total preparations of synaptonemal complexes of spermatocytes I from sterile heterozygous male mice--t12/tw18; tw5/twPa-1; twPa-1/tw18 was performed. T/tw18 and C3H/N fertile heterozygotes were used in each variant as control. The cells are karyotyped in all experiments, as based on the measurements of the length of 19 SC autosomes and SC sex complex. All sterile compounds (spermatocytes) demonstrate high frequency of different types of associations (72%) between sex chromosomes and the autosome 17 carrying a chromosomal aberration in the region of the T-locus. The heterozygotes tx/ty used in our experiments show no disruption of chromosome synapsis, when even studied under electron microscope, though some atypical changes in the ultrastructure of chromosome axes and frequent atypical associations of the axes of XY-sex bivalents in sterile heterozygous animals exist.  相似文献   
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