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161.
STUDY OBJECTIVE--To determine whether mortality from breast cancer could be reduced by repeated mammographic screening. DESIGN--Birth year cohorts of city population separately randomised into study and control groups. SETTING--Screening clinic outside main hospital. PATIENTS--Women aged over 45; 21,088 invited for screening and 21,195 in control group. INTERVENTIONS--Women in the study group were invited to attend for mammographic screening at intervals of 18-24 months. Five rounds of screening were completed. Breast cancer was treated according to stage at diagnosis. END POINT--Mortality from breast cancer. MEASUREMENTS AND MAIN RESULTS--All women were followed up and classed at end point as alive without breast cancer, alive with breast cancer, dead from breast cancer, or dead from other causes. Cause of death was taken from national mortality registry and for patients with breast cancer was validated independently. Mean follow up was 8.8 years. Altogether 588 cases of breast cancer were diagnosed in the study group and 447 in the control group; 99 v 94 women died of all causes and 63 v 66 women died of breast cancer (no significant difference; relative risk 0.96 (95% confidence interval 0.68 to 1.35)). In the study group 29% more women aged less than 55 died of breast cancer (28 v 22; relative risk 1.29 (0.74 to 2.25)). More women in the study group died from breast cancer in the first seven years; after that the trend reversed, especially in women aged greater than or equal to 55 at entry. Overall, women in the study group aged greater than or equal to 55 had a 20% reduction in mortality from breast cancer (35 v 44; relative risk 0.79 (0.51 to 1.24)). OTHER FINDINGS--In the study group 100 (17%) cancers appeared in intervals between screenings and 107 (18%) in non-attenders; 51 of these women died from breast cancer. Cancers classed as stages II-IV comprised 33% (190/579) of cancers in the study group and 52% (231/443) in the control group. CONCLUSIONS--Invitation to mammographic screening may lead to reduced mortality from breast cancer, at least in women aged 55 or over.  相似文献   
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  1. Scots pine Pinus sylvestris was originally introduced to Iceland in the beginning of the 20th Century. Extensive plantings started in the late 1940s and, in total, 2–3 million Scots pine seedlings were planted, mainly originating from two counties in northern Norway. Part of this plant material was imported as seedlings.
  2. Pine woolly aphid Pineus pini was introduced to Iceland before 1940, most likely on imported seedlings in 1937.
  3. High mortality of Scots pine, concurrent with high infestation of the pine woolly aphid, was observed in Iceland during the late 1950s and 1960s and planting was discontinued.
  4. Provenance trials with Scots pine were established in Iceland in 2004–2006. They consisted of 15 provenances from Norway, four from Finland, four from Scotland, one from Russia, one from the Austrian Alps and three first generation Scots pine provenances from Iceland, collected from survivors of the epidemic in the 1950s and 1960s. In total, there were 28 provenances.
  5. The Icelandic provenances had significantly lower P. pini infestation than all the provenances of non‐Icelandic origin, which indicates that natural selection in Scots pine in Iceland has occurred in favour of individuals less susceptible to P. pini.
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