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1.
Oligonucleotide mapping of the RNA genome was applied for analysis of poliovirus clinical isolates in Byelorussia in 1967-1985. All the maps have been clearly shown to resemble the reference maps of the corresponding vaccine strains. Examination of the oligonucleotide maps of poliovirus isolates provides a measure of distribution of some of the mutations over the viral genome.  相似文献   
2.
The role of the tube feet in locomotion of the ophiuranAmphipholis kochii Lütken is examined. During stepping movements the anterior tube feet attach themselves to the supporting surface and at the end of the step they detach themselves from it. The signal for detachment is deviation of the foot into the posterior (relative to the direction of motion) position. Because of this arrangement of the "stepping" mechanism of the tube feet the task of coordinating their activity with arm movements is greatly simplified. The feet "automatically" attach themselves to the support when the arm which carries them plays the role of motor; conversely, they detach themselves from the support when this arm moves forward. The CNS thus evidently does not participate in foot and arm movement coordination. It simply assigns the general direction of motion to all the feet and coordination takes place "automatically" as a result of the special properties of the "stepping" mechanism of individual feet.Institute of Oceanology, Academy of Sciences of the USSR, Moscow. Institute of Problems of Information Transmission, Academy of Sciences of the USSR, Moscow. Moscow State University. Translated from Neirofiziologiya, Vol. 8, No. 6, pp. 633–639, November–December, 1976.  相似文献   
3.
During movement of the ophiuranAmphipholis kochii Lutken, any one of its arms can point forward and, consequently, any arm can perform different functions. The arm, when separated from the ophiuran together with the adjacent part of the nerve ring, is capable of complex motor acts, including locomotion. Division of the nerve ring in the ophiuran disturbs coordination of the arms. The results of experiments in which one or more arms were amputated showed that the choice of leading arm and of method of locomotion depends mainly on afferent impulses received from the arms. The results indicate that the neural centers of individual arms possess relative autonomy. Coordinated working of the centers is achieved through their interaction. This interaction ensures the distribution of functions between the arms in accordance with the motor task to be undertaken and coordinates the activity of the arms in time. The dominant role in the distribution of functions between the arms is played by the center of the leading arm, which controls the activity of at least the adjacent centers.Institute of Oceanology, Academy of Sciences of the USSR, Moscow. Institute of Problems in Information Transmission, Academy of Sciences of the USSR, Moscow. Moscow State University. Translated from Neriofiziologiya, Vol. 8, No. 5, pp. 529–537, September–October, 1976.  相似文献   
4.
In the large pyramidal neurons of the pariental cortex of cat during the slow-waved phase of sleep in comparison to the state of awake, an uneven decrease of the level of 3H-leucine inclusion was established in different functionally specialized zones of the cell. Using electron microscopy, a decrease in the number of polysomes and membrane-attached ribosomes was shown in the perinuclear zone of large pyramids in slow-waved phase of sleep. The results obtained suggest a decrease in the intensity of protein synthesis in comparison to the state of awake.  相似文献   
5.
One hundred and eight vaccine-derived strains of types 1, 2, and 3 poliovirus (25 PV1, 34 PV2, and 48 PV3) isolated in Belarus in 1960-1999 were analyzed by double restriction fragment length polymorphism assay (RFLP-1, -3D1). Forty-four (40.7%) of strains were genetically modified. Eight (7.4%) PV were modified by mutation, 16 (14.8%) by recombination, and 20 (18.5%) by both mutation and recombination. The genomes of 16 PV were analyzed by multiple RFLP technique covering VP1-, VP1/VP2A-, P2-, 3AC-, and 3D1-coding regions. The majority of recombinants were "simple" (with one crossing over site). One strain was "double" recombinant (two crossings over sites) and one more "multiple" recombinant (three crossing over sites). Partial nucleotide sequencing of some recombinant strains showed that the degree of these strains' divergence was less than 1% in comparison with the original vaccine viruses.  相似文献   
6.
It is recommended to use the capacity of pathogenic staphylococci to be lysed by polyvalent therapeutic staphylococcal bacteriophage in the capacity of an additional simple and accessible criterion of staphylococcus pathogenicity. Of 147 strains of the pathogenic plasmacoagulating staphylococci 101 were lysed by the phage and of 166 nonplasmocoagulating nonpathogenic strains--only 6. This test correlated with the other signs of staphylococcus (lecithinase and hemolytic activity). The simplicity and sufficient specificity of this test permits to use it in any practical laboratory. Polyvalent diagnostic phage can be used on the basis of therapeutic bacteriophage by its additional adaptation to the pathogenic strains of staphylococcus.  相似文献   
7.
Circahoralian rhythm of the intensity of 3H-lysine incorporation into proteins of the retina ganglionic cells and of the protein synthesis rate in the isolated retina with an amplitude of fluctuations of 35-36% of the mean has been found in active adult susliks. During hibernation, no circahoralian fluctuations of protein metabolism were recorded. Circahoralian rhythms of protein metabolism can serve as a marker of the tissue functional activity.  相似文献   
8.
The method for the calculation of actual hepatitis B morbidity and the formula for such calculation are proposed. The calculations presented in this work have demonstrated that the actual spread of virus B hepatitis is many times higher than the registered morbidity rate and that there are more than 30 undetected hepatitis patients per each manifest case of the disease. This requires additional approaches to the study of the epidemiology of virus B hepatitis, the ways and factors of its transmission.  相似文献   
9.
Using the ecological and natural-science approaches, the authors have come to the conclusion that microorganisms, pathogenic for humans (animals), are their parasites for whom the disease of their biological host is the necessary condition of their existence as a biological species. And accordingly, microorganisms, opportunistic in humans (animals) are their parasites and commensals, as well as saprophytes, for whom the disease of their host is not the necessary condition of their existence in nature. The biological host is a symbion necessary for the existence of pathogenic and most opportunistic microorganisms, but for a pathogenic microorganism the disease of the host is the result of symbiotic relationships, while for an opportunistic microorganism the disease of the host is the consequence of disturbances in symbiotic relationships. Such view of pathogenicity is important for creating a scientifically grounded theory of the liquidation of human infectious diseases.  相似文献   
10.
On the basis of analysis of literature and personal observations and studies the authors explain a number of epidemiological and clinical peculiarities of intestinal infections with various pathogenic doses of the causative agents; under the term pathogenic dose is understood the minimal amount of microbes necessary for the onset of the disease with the natural mechanism of transmission of the infection. Regularities of the effect of the pathogenic dose of the causative agent on the epidemic process common for intestinal infections were formulated.  相似文献   
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