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OBJECTIVE: To describe the epidemiology of suicide pacts in England and Wales DESIGN: Analysis of the death certificates and coroners'' records of all people who died in pacts between 1 January 1988 and 31 December 1992. SUBJECTS: 124 people who committed suicide in 62 pacts. RESULTS: Suicide in a pact accounted for 0.6% of all suicides (124/19721), a rate of 0.6 per million people aged 15 and over. Forty eight pacts were between married couples and five were between family members. The mean age was 56 years. 99 of the 124 subjects were of occupational social classes I-III. Poisoning by car exhaust fumes and drugs accounted for 116 deaths, with both members of each pair using the same method. CONCLUSIONS: Suicide pacts are rare and less common than they were 35 years ago, although the epidemiological profile is similar. People who commit suicide in a pact are more likely than those who commit suicide alone to be female, older, married, and of a high social class. 相似文献
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Synthesis of basic fibroblast growth factor upon differentiation of rat mammary epithelial to myoepithelial-like cells in culture 总被引:3,自引:0,他引:3
Acidic fibroblast growth factor (aFGF) mRNA was detected in a rat mammary fibroblastic cell line, but not in rat mammary epithelial cell lines or myoepithelial-like cell lines. Basic FGF (bFGF) mRNA was detected in both the fibroblasts and the myoepithelial-like cells, but was absent from the epithelial cells. A series of cell lines representing stages in the differentiation pathway of epithelial cells to a myoepithelial-like morphology showed an increase in the amount of bFGF mRNA and activity present and the FGF from the myoepithelial-like rat mammary 29 cells was able to displace [125I]-bFGF specifically bound to rat mammary fibroblasts. FGF activity was also present in an extract of rat mammary gland. Analysis of cell extracts and conditioned medium indicated that FGF activity was cell-associated. The cell-associated bFGF was resistant to degradation by trypsin. Extraction of myoepithelial-like cells with Triton X-100 and 2 M NaCl showed that 50-65% of the cell-associated bFGF was in a detergent-resistant but 2 M NaCl-labile structure. Thus, the synthesis of bFGF is developmentally regulated in rat mammary cell lines, and at least 50% is present in the extracellular matrix. 相似文献
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Patterns of denitrification loss from grazed grassland: Effects of N fertilizer inputs at different sites 总被引:1,自引:1,他引:0
Factors influencing the seasonal and daily variation in denitrification rates in grazed swards were examined at 5 experimental
sites in England with wide ranging environmental/geographic conditions. There was a wide range of fertilizer inputs at each
site. Rates of denitrification were estimated by a coring and field incubation technique using acetylene to inhibit the reduction
of N2O to N2. Major features of the detailed results from two of the sites were: (i) the large ranges in rates of loss, (ii) the relatively
low contributions to total annual loss during autumn and winter, (iii) the apparent association of high rates of loss with
fertilizer additions made when the soil was wet or immediately preceding a rainfall event, and (iv) significant losses from
soil at 10–30 cm in the profile. Multiple quadratic regression analysis of the effects of soil NO3
--N, soil temperature and water was used to explain variability in rates of loss. When separate regressions were fitted within
each site × year × season × fertilizer level subset, 51% of the variation in loss was explained on a poorly drained fine loam/silt
but only 38% on a freely drained loam. 相似文献