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881.
882.
We studied the matrilinear genetic structure of the Siberian tit Parus cinctus by sequencing 911 bp of the mitochondrial control region of 56 birds from Fennoscandia and 3 from Yakutia, central Siberia, representing subspecies P. c. lapponicus and P. c. cinctus , respectively. One major haplotype comprised 35.7% of all birds and was present in all Fennoscandian populations. Sequence variation of 5 museum specimens from Norway fitted with the pattern of the present-day birds. The nucleotide diversity was 0.00205±0.00025 in the Fennoscandian population and no population structuring was detected. The star-like phylogeny suggests a recent expansion of the population size in the evolutionary time scale. A modern decline of the population size from 200 000 pairs to 50 000 pairs in Finland has resulted from cutting and fragmentation of old-growth forests, but the effects of this could not yet be detected in the mtDNA pattern. However, the nucleotide diversity differed among populations being the highest at Kuusamo, close to the Russian border. Conceivably, the gene flow maintained by the substantial migration of Siberian tits is sufficient to prevent differentiation of local populations in Fennoscandia. Presumably the large conservation areas in NE Finland and on the Russian side of the border contribute to the high genetic variation observed in the Kuusamo population. Comparison of the mtDNA phylogeny of the Siberian tit with the phylogenies of the great tit, the blue tit and the willow tit showed that the Siberian tit and some other non-migratory species of the foliage gleaning guild share similar post glacial histories in the western palaearctic. 相似文献
883.
L. Kalevi Korhonen Elsa Korhonen Markku Hyyppä Reijo Punnonen 《Histochemistry and cell biology》1966,6(2):164-167
Summary Positive histochemioal reaction for carbonic anhydrase (CAH) activity was observed in the glandular and lining epithelium of human and rat uteri. The CAH activity in the rat endometrium showed cyclic changes during the estrous cycle. Only one main component of CAH activity was revealed by electrophoresis, under conditions when the erythrocytes showed several isozymes. 相似文献
884.
Juha Karjalainen Minna Rahkola Markku Viljanen Inna N. Andronikova Valentin A. Avinskii 《Hydrobiologia》1996,322(1-3):249-253
The results of a joint Russian-Finnish investigation on zooplankton in Lake Ladoga are presented, and a comparison is made between two sampling techniques, tube sampler and plankton net, and between two counting methods. The precision of subsampling and sampling is further discussed on the basis of zooplankton data gathered in Lake Saimaa, Finland. The comparison clearly indicates that a tube sampler is required for reliable sampling of small-sized animals, while a plankton net saves time and is a more economical sampler for large, rare or active animals. The comparison between the results obtained by Finnish and Russian workers, using different counting procedures, shows that the main groups of crustacean zooplankton are similarly counted and identified in the two laboratories. 相似文献
885.
886.
Kati Pasanen Jari Parkkari Matti Pasanen Hannele Hiilloskorpi Tanja M?kinen Markku J?rvinen Pekka Kannus 《BMJ (Clinical research ed.)》2008,337(7661):96-99
Objective To investigate whether a neuromuscular training programme is effective in preventing non-contact leg injuries in female floorball players.Design Cluster randomised controlled study.Setting 28 top level female floorball teams in Finland.Participants 457 players (mean age 24 years)—256 (14 teams) in the intervention group and 201 (14 teams) in the control group—followedup for one league season (six months).Intervention A neuromuscular training programme to enhance players’ motor skills and body control, as well as to activate and prepare their neuromuscular system for sports specific manoeuvres.Main outcome measure Acute non-contact injuries of the legs.Results During the season, 72 acute non-contact leg injuries occurred, 20 in the intervention group and 52 in the control group. The injury incidence per 1000 hours playing and practise in the intervention group was 0.65 (95% confidence interval 0.37 to 1.13) and in the control group was 2.08 (1.58 to 2.72). The risk of non-contact leg injury was 66% lower (adjusted incidence rate ratio 0.34, 95% confidence interval 0.20 to 0.57) in the intervention group.Conclusion A neuromuscular training programme was effective in preventing acute non-contact injuries of the legs in female floorball players. Neuromuscular training can be recommended in the weekly training of these athletes.Trial registration Current Controlled Trials ISRCTN26550281. 相似文献