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531.
Proteomic technologies revealed products of 2 genes (α-actin and albumin) in a human myocardium tissue. They exist as fragments and their appearance and increased content correlated with age. The age-related variants differ from the mature forms of these proteins by the absence of N-terminal fragments of the amino acid sequences. In the chronic ischemic heart disease (CIHD), these age-related proteins were found in 50% of cases (in the age group 31–40 years), whereas in the control group such combination was detected only in 10% of the examined individuals. Subsequent studies in this field would probably reveal molecular mechanisms responsible for impairment and/or ageing of the myocardium and also of adaptation/disadaptation mechanisms in the CIHD.  相似文献   
532.
Blood levels of lactate and glucose were measured in 15 healthy male athletes with the purpose of evaluating possible correlation between their blood values and intensity and selectivity of attention, after a 30-min steady-state test performed at 60 and 80% of maximal oxygen consumption (VO2max). On the basis of the results, we conclude that, during aerobic exercise, a worsening of attentional capabilities does not occur unless there is an increase of blood lactate above 4?mmol/l.  相似文献   
533.
The disposition of cercarial papillae of 68 pre-identified Schistosoma species was established. All the cercariae originated from Africa and Madagascar and were either obtained from natural or experimental infections, and belonged to three species Schistosoma haematobium, S. bovis and S. curassoni. Discriminant analysis was based on nine characters: average values, skewness and kurtosis of three cercarial indices (AD, AL and U) for each sample or isolate. AD, AL correspond respectively to the relative distance between dorsal and lateral papillae. U corresponds to the total number of tail stem papillae. With the exception of two cases of the 68 (one of them corresponding to cercariae shed by a non-African experimentally infected snail), the method enabled discrimination of S. haematobium, S. bovis and S. curassoni.  相似文献   
534.
We examined modification of clay forms by tufted capuchins (Cebus apella) by presenting groups of subjects with clay, paint, stones, leaves, and sticks. In Experiment 1, 7 of 10 subjects reshaped portable forms with their hands and with stones, and decorated them with leaves and paint. In Experiment 2, 9 subjects marked clay slabs manually and with stick and stone tools. The manipulative propensities of Cebus can help us to understand psychological processes that underlie artistic expression in Homo and Pan.  相似文献   
535.
536.
Opercular and surfacing activity were observed in the Indian catfish Clarias batrachus and Heteropneustes fossilis. In the series A experiments, the opercular activity was monitored under two experimental conditions, viz., (1) surfacing allowed and (2) surfacing prevented. A statistically significant elevation of the rate of opercular activity was observed when air breathing was prevented in both species. In addition, a significant prevention effect and a time of day dependence of that were noticed in both species. In the series B experiments, temporal patterns of surfacing and air-gulping activities were examined under an artificial LD 12:12 schedule at 2-h intervals over a period of 48 h. The inter air-gulping interval in minutes between two consecutive bouts was also recorded four times each day in both species. A significant 24-h rhythm was found for the rate of surfacing activity and length of the inter air-gulping interval in both species. However, the overall activity appears to be much higher in Heteropneustes fossilis as compared to Clarias batrachus.  相似文献   
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