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141.
Achim Kostrzewa 《当今生物学》2020,50(1):44-51
Emperor Pinguin – a bird of superlative The antarctic ecosystem is home of 200 million seabirds. 26 million of them belong to the penguins and only 600.000 are Emperor Penguins. They breed along the remote coasts of Antarctica. Their first colony was discovered in 1902. In the course of the 1950ies more colonies were detected and today with the help of satellite technique we know more than 54 in total. The breeding cycle starts during winter, when a 1.000 kilometer sea ice belt surrounds the continent. Emperor Penguins use Polynjas during this time to get access to the food sources in the sea. During incubation and breeding they are very hard to study due to stormy weather and temperatures of sometimes below minus 30° Celsius. From October onwards the first big icebreakers are capable to reach some of these places and biologists can start to study breeding success by counting chicks and adults. The few best monitored colonies are in the reach of Antarctic winter stations. Remote sensing of faeces stain on the ice give an introspection of the spacing of colonies all over the coasts. Counts in the colonies give figures of population sizes in relation to faeces covered areas. So we got a rough idea about the number of individuals. Satellite imaging over the last 40 years has provided data on the sea and glacier ice loss: Most loss is to be found in western Antarctica, but also in eastern Antarctica we can find more and more melting due to raising temperatures. 相似文献
142.
-Prolyl-
-leucyl-glycinamide (MIF-1) is known to attenuate apomorphine-induced stereotypies in adult rats that are lesioned as neonates with 6-hydroxydopamine (6-OHDA). To test whether MIF-1 would affect dopamine (DA) agonist-induced and serotonin (5-HT) agonist-induced oral activity, both intact and neonatal 6-OHDA-treated rats were studied. Rats at 3 days from birth were injected with desipramine (20 mg/kg, IP), 1 h before 6-OHDA HBr (100 μg, salt form, in each lateral ventricle) or its vehicle, saline-ascorbic acid (0.1%). At approximately 6 months rats were treated with MIF-1 (0.1, 1.0, or 10.0 mg/kg, IP), 10 min before SKF 39393 HCl (1.0 mg/kg, IP) or m-chlorophenylpiperazine 2HCl (m-CPP 2HCl; 0.5 mg/kg, IP), DA D1 and 5-HT1C,2 receptor agonists, respectively. Although both agonists increased oral activity in control and neonatal 6-OHDA-treated rats, MIF-1 did not modify the response. In rats that received either of the three doses of MIF-1 for 21 consecutive days, there was still no observed effect of MIF-1 on the oral response of control and 6-OHDA-lesioned rats to SKF 38393 and m-CPP. These findings indicate that MIF-1 does not modify the oral activity response of supersensitized D1 and 5-HT1C receptors in adult rats that are lesioned neonatally with 6-OHDA. 相似文献
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Dr. Achim Kostrzewa 《当今生物学》2012,42(5):320-327
Birds of prey and pesticides During the years of 1940 to the 1960ties the use of persistent organic pestcides (POP's) became common. DDT was used widely to kill pest insects in farming and forrestry. This resulted in the so called “pesticide chrash” in many bird populations namely in Peregrines and Ospreys. These species were poisoned via their food webs, from insects to birds or fish which had accumulated POP's like DDT. Between 1970 and 2004 all POP's were banned and since 1970 the populations grew again supported by nature conservation and wildlife management. Nowadays new generations of pesticides are in use, which are less persitant but still highly toxical for birds of prey. Therefore we need to control them by biomonitoring of relevant species like peregrine falcons and others. 相似文献
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