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901.
The plasmaprotein of a specimen of Grampus griseus
G Cuvier, captured in the Western Mediterranean, is studied for the first time and the data obtained are compared with data previously determined by the same method (microelectrophoresis on cellulose acetate gel) for Stenella, Delphinus and Phocaena. Some hematochemical values related to glycemia, azotemia and cholesterolemia (total and fractional) are also given and discussed, together with data on glutamic oxalacetic and glutamic pyruvic transaminases; special reference is made to the theory of Cornelius (1963) on hepatic glutamic pyruvic transaminase.Contributions on Cetacea: XXIV. Prepared with the assistance of the Schweizerischer Nationalfonds zur Förderung der wissenschaftlichen, Forschung (Swiss National Fund for the Promotion of Scientific Research, Grant No. 4606) and the C.N.R.S. (National Centre for Scientific Research), Paris. 相似文献
902.
903.
Despite its evolutionary significance, behavioural flexibility of social response has rarely been investigated in insects. We studied a host–social parasite system: the slave-making ant Polyergus rufescens and its host Formica rufibarbis. Free-living host workers from parasitized and from unparasitized areas were compared in their level of aggression against the parasite and alien conspecifics. We expected that a seasonal change would occur in the acceptance threshold of F. rufibarbis workers from a parasitized area towards the parasite, whereas F. rufibarbis workers from an unparasitized area would not show substantial changes connected with the parasites peak in activity (raiding and colony-founding season). The results showed a significant adaptive behavioural flexibility of host species workers and are consistent with the acceptance threshold models (Reeve 1989) prediction that recognition systems are not fixed but context-dependent. In particular, host workers from the unparasitized area were highly aggressive towards the parasite regardless of the season, whereas host workers from the parasitized area significantly increased their aggression towards the parasite during its raiding and colony-founding season. Being able to detect and possibly kill a Polyergus scout searching for host nests can be an effective strategy for a Formica colony to avoid being raided or usurped by a parasite queen. 相似文献
904.
Lerchl A 《Die Naturwissenschaften》2004,91(9):422-425
The effects of month of birth (MOB) on life expectancy of a German subpopulation was investigated. Data from people who died in North Rhine Westphalia in the years 1984 (n=188,515) and 1999 (n=188,850) were analyzed. For comparative purposes, all deaths that occurred at an age of <50 years were excluded (1984: 8.4%; 1999: 6.2%). In general, individuals born in May through July had the lowest age at death (1984: 75.27±0.09 years; 1999: 77.58±0.09 years), while those born between October and December had the highest (1984: 75.98±0.08 years; 1999: 78.35±0.09 years), supporting earlier findings. The observed amplitudes (differences between highest and lowest values) were more pronounced in men than in women. When comparing these data of MOB effects on life expectancy with earlier findings in Australia, Austria, Denmark, Ukraine, and the USA, it is evident that a negative correlation exists between the average age at death and the MOB amplitudes. Separate analyses by gender, possible for the data from Germany, the Ukraine, and the USA, revealed a significant negative correlation for men, but not for women. A new hypothesis is therefore presented describing an influence of life quality, as reflected by average life expectancy, on the extent of MOB effects; for example, seasonally variable sensitivities during pregnancy/early childhood. 相似文献
905.
Light,timing of biological rhythms,and chronodisruption in man 总被引:3,自引:2,他引:3
This paper reviews abundant evidence suggesting that causes and course of aging and cancers can be considered as being both light- and rhythm-related. We define chronodisruption as a relevant disturbance of orderly biological rhythms over days and seasons and years in man. Light is the primary external mediator and melatonin a primary internal intermediary of such disturbances, which can result in earlier deaths via premature aging and cancers. We conclude that experimental and epidemiological research can provide further insights into common denominators of these chronic processes and may offer novel and uniform targets for prevention. 相似文献
906.
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909.
Fluorescent in situ Hybridization (FISH) was carried out for three cases of abnormal karyotypes in prenatal studies. Two concerned de novo structural anomalies and the third a marker chromosome. The origin of the extra material could be defined in all three cases, which gives a better insight into the relationship between genotype and phenotype and makes more adequate genetic counselling possible. 相似文献
910.
Fetomaternal haemorrhage (FMH) was studied after 46 cordocenteses. α-Fetoprotein (AFP) concentration and Kleihauer staining of maternal blood, taken both before and after the procedure, revealed increases in AFP values of more than 40 per cent in 30 per cent of the patients examined; fetal haemorrhage of more than 0.25 ml was detected in 46 per cent of the cases by the Kleihauer test. In the second trimester of pregnancy both techniques are comparable, while in the third trimester the Kleihauer technique appears to be more sensitive in detecting FMH after cordocentesis. An anterior position of the placenta is a risk factor for FMH. 相似文献