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In Finland (population 5 million) the organised Pap screening programme for preventing cervical cancer has been in action already for 45 years. Women aged 30 to 64 are targeted (N 1.25 million) and the screening interval is five years. The programme invites women seven times in a lifetime; the attendance rate per one screening invitational round is 73%. The programme has affected markedly the cervical cancer rates in our country. During the decennia of its action there has been about 80% decrease in the age-adjusted cervical cancer incidence and mortality rates. The current age-standardised incidence rate is 4 and mortality rate 1 per 100,000 woman-years. In the current article we describe the organisational aspects of the programme; and pay attention to renovation of the programme taken place during the last decade when novel technological alternatives have been started to be used as the screening tests. By expanding the coverage and compliance of screening we still expect to increase the impact of the programme. Same time, efforts are needed to avoid overuse of services due to spontaneous screening, in order to decrease potential adverse effects and improve overall cost-effectiveness. A large-scale public health policy trial on Human papillomavirus (HPV) screening is on-going. Cross-sectional information available thus far suggests promising results. Follow-up of cancer rates after screening episodes are still required to evaluate optimal screening policies (e.g., screening intervals by age groups, and starting and stopping ages). We propose speeding up the use of modern technological alternatives in organised screening programmes.  相似文献   
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Here, we use a unique long‐term data set on total organic carbon (TOC) fluxes, its climatic drivers and effects of land management from a large boreal watershed in northern Finland. TOC and runoff have been monitored at several sites in the Simojoki watershed (3160 km2) since the early 1960s. Annual TOC fluxes have increased significantly together with increased inter‐annual variability. Acid deposition in the area has been low and has not significantly influenced losses of TOC. Forest management, including ditching and clear felling, had a minor influence on TOC fluxes – seasonal and long‐term patterns in TOC were controlled primarily by changes in soil frost, seasonal precipitation, drought, and runoff. Deeper soil frost led to lower spring TOC concentrations in the river. Summer TOC concentrations were positively correlated with precipitation and soil moisture not temperature. There is some indication that drought conditions led to elevated TOC concentrations and fluxes in subsequent years (1998–2000). A sensitivity analysis of the INCA‐C model results showed the importance of landscape position, land‐use type, and soil temperature as controls of modeled TOC concentrations. Model predictions were not sensitive to forest management. Our results are contradictory to some earlier plot‐scale and small catchment studies that have shown more profound forest management impacts on TOC fluxes. This shows the importance of scale when assessing the mechanisms controlling TOC fluxes and concentrations. The results highlight the value of long‐term multiple data sets to better understand ecosystem response to land management, climate change and extremes in northern ecosystems.  相似文献   
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Taulavuori  Kari  Niinimaa  Ahti  Laine  Kari  Taulavuori  Erja  Lähdesmäki  Pekka 《Plant Ecology》1997,133(2):181-189
The annual course of frost resistance (LT50) and the pH of the cell effusate in needles of two-year-old Scots pine seedlings were monitored in a field experiment in Oulu, Northern Finland (65° N, 25° E) during 1995. The aim of the work was to to develop model to predict the annual variation in frost resistance by pH of the cell effusate and meteorological data. The seedlings were covered with a fibre cloth shelter which transmitted sufficient light for them to experience the photoperiod, but prevented the accumulation of snow over them. The shelter above the seedlings was removed at the beginning of May and erected again at the end of September. The seedlings were watered only for the time when the shelter was removed, and received fertilizer only during the previous summer (1994).Frost resistance was only -5° C during the growing season but more than -100° C during the winter rest period. It was about -10° C at the end of August, increased to -55° C in the next three weeks, and reached -100° C at the beginning of October. The pH of the cell effusate was lowest during the growing season and highest in winter, the difference being about one and half pH unit. Needles exposed to -196° C showed pH from 4.0 in summer to 5.5 in winter, while pH of the non-frozen needles varied from 5.0 to 6.5, respectively. Seasonal variation in frost resistance was explained by a regression model well (R2 = 0.9) when day length, minimum air temperature and pH were entered as variables.  相似文献   
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Summary The pro 2(I) collagen gene has been screened for Bgl II restriction fragment length polymorphisms (RFLPs) in the Finnish population which has a long background of genetic isolation. As genetically isolated populations tend to demonstrate deviations in the degree of heterozygosity, the RFLP markers described in more heterogeneous populations can not be utilized as such in the former. This proved to be the case with Bgl II polymorphism within the pro 2(I) collagen gene, the gene involved in different disorders of connective tissue. This report describes the presence of three new RFLP-loci and the absence of one RFLP-locus, which had been earlier reported from a population with a genetic background remote from the population studied here.  相似文献   
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Phylogenetic relationships and levels of geographic differentiation of two closely related bipolar taxa, Cladonia arbuscula and Cladonia mitis, were cladistically examined with ITS regions, SSU rDNA introns, partial beta-tubulin, and partial glyceraldehyde 3-phosphate dehydrogenase (GAPDH) genes. In the combined analysis of the four genes, C. arbuscula was paraphyletic, while C. mitis, nested within C. arbuscula, formed a strongly supported monophyletic group. C. arbuscula samples were divided into three separate clades: "arbuscula I," appearing as basal to the other ingroup taxa, "arbuscula II," and "arbuscula III" (the latter represented by only one specimen), which were not correlated with any morphological trait. Only C. mitis specimens formed a morphologically and chemically distinct group. None of the main clades was correlated with geographic origin. The separate analyses were poorly resolved, and in most cases samples from "arbuscula I," "arbuscula II," and "arbuscula III" clades were intermixed. An incongruence test revealed conflict among the four gene regions in almost all cases. Only ITS regions and introns were not significantly incongruent, suggesting lack of recombination within the ribosomal DNA locus. Incomplete lineage sorting and recombination were considered to be the main reasons accounting for the incongruencies. The high proportion of shared polymorphisms between the "arbuscula I" and "arbuscula II" clades, especially found from the beta-tubulin gene and from the ITS regions, and the lack of corroborating morphological characters both indicate a short history of reproductive isolation among the groups. The lack of genetic differentiation among the northern and southern samples within the main clades indicates a relatively recent gene flow, which may have resulted from migrations during the Pleistocene glaciations or from more recent long-distance dispersal.  相似文献   
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We estimated year-class strength (YCS) of whitefish and peled by VPA in two boreal reservoirs Lokka and Porttipahta with mean regulation of water level amplitudes of 2.34 and 2.49 m, respectively. YCS of peled Coregonus peled(Gmelin) was related to winter drawdown most probably via egg desiccation. In the relatively shallow Lokka dissolved oxygen deficiency in late winter also had a negative impact on survival of eggs and year-class strength. In contrast to peled, whitefish Coregonus lavaretus(L.) indicated no significant relationship with winter drawdown or dissolved oxygen level. The obvious reason for the pattern is that peled spawn on the reservoir bottom, but whitefish spawn in the ascending rivers, which are mainly unaffected by reservoir regulation.  相似文献   
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Developing leaves of several mature Betula pendula trees planted for landscaping turned red when a sudden cold period occurred during the high light conditions of Spring. At the same time the leaves of other trees remained green. The effect of street lamp light on leaf colouration of the B. pendula trees with Springtime red- and green-emerging leaves was studied in the cool Autumn weather. The result suggests that the chlorophyll a and b, and carotenoid degradation of B. pendula leaves was not delayed by the street lamp light. The intensity of light and the amount of red and far-red light of the white lamp light was obviously very low to delay autumnal leaf colouration of B. pendula.  相似文献   
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