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91.
The distribution of grooming and touching behaviours was recorded in a group of captive ring-tailed lemurs. Grooming was found to be performed chiefly by older, higher ranking animals; touching (i.e., “reach out and touch” behaviour) was directed primarily by younger, low ranking animals to older, high ranking individuals. It is suggested that such touching is a submissive gesture in this species.  相似文献   
92.
Extensibility, contractile function and resistance to excess calcium of the right atrium myocardium were studied in normotensive Wistar-Kyoto and August rats and in spontaneously hypertensive rats (SHR). It was shown that long-term stress results in a decrease in the measured parameters in normotensive animals. SHR do not show any stress-induced disturbances. It was discovered that in intact SHR rats, the myocardium has a greater resistance to excess calcium, indirect evidence for higher efficiency of the Ca-pump of the sarcoplasmic reticulum in cardiomyocytes of SHR animals, which is apparently a constituent part of the mechanism of such animals' heart increased resistance to stress-induced damage.  相似文献   
93.
THE TIMING OF DIVISION IN CHLAMYDOMONAS   总被引:3,自引:2,他引:1  
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94.
The neutrophil-stimulating properties of 38 S. aureus strains and 32 S. epidermidis strains were studied in the reaction of luminol-mediated chemiluminescence. All S. aureus strains and 29 S. epidermidis strains were found to possess neutrophil-stimulating activity, the mean activity index for S. aureus being significantly higher. The stimulating activity of the strains varied within a wide range (the variation coefficient was 120.0 +/- 21.9%) and did not correlate with the content of protein A in bacterial cells and the degree of their hydrophoby. The opsonization of staphylococci with normal human serum enhanced the neutrophil reaction 1.5- to 100-fold and simultaneously leveled out the chemiluminescence indices in experiments with different strains (the variation coefficient was 8.0 +/- 1.5%). The nature of the neutrophil-stimulating effect of staphylococci and its relationship to the exploratory reactions of phagocytes are discussed.  相似文献   
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Samples of marine pleuston were collected from the sea-surface along considerable sections of the track of Eye of the Wind during its 2-year circumnavigational expedition 'Operation Drake' from November 1978 to October 1980. One hundred and eleven of the tow samples contained insects of the genus Halobates . They were assigned to four oceanic species: H. micans, H. sericeus, H. germanus and H. splendens; two coastal species: H. maculatus, H. princeps, and one undescribed species. Various development stages of the oceanic species were found. The locations, time of collection and surface temperatures where sea-skaters were collected are tabulated. Distributional boundaries and population densities of the oceanic species collected are discussed.  相似文献   
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Rosette and single-element strain gauges were implanted on the tibia in 2 dogs and recordings were made during locomotion on a treadmill. At foot contact and during the swing phase of locomotion, bone strains were low and directions of the principal strains were variable. There was a large shift in the directions of the principal strains at the beginning of the stance phase and bone strains were considerably higher. Peak strain occurred midway through the stance phase. At that time, the maximum principal strain (tension) was directed upwards and anteriorly between 30 and 60 degrees with respect to the long axis of the tibia. These bone strain patterns in the dog are similar to those found in sheep while both differ markedly from those found in humans.  相似文献   
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