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B Sibbald 《CMAJ》1998,159(1):64-65
Should vaccination of physicians against hepatitis B, as well as subsequent screening for the virus, be mandatory? The CMA says no: the voluntary route is the way to go. But Health Canada disagrees. Its new guidelines call for mandatory vaccination and subsequent screening of exposure-prone physicians for the virus.  相似文献   

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The nitrogen‐fixing legume Lupinus polyphyllus invaded semi‐natural mountainous grasslands across Europe during the last decades. This invasion resulted in degraded habitats through changes in the structure and function of the mountain meadow vegetation. In our study, we analyzed (1) the effects of increasing cover of L. polyphyllus on the seed bank of mountain meadows, and (2) the potential of the seed bank of these stands for active restoration of mountain meadows in terms of species composition and number. We conducted a seed bank analysis on 84 plots with increasing cover of L. polyphyllus in three mountain‐meadow types of the Rhön Biosphere Reserve, Germany. Seedlings from 119 species germinated from the seed bank samples, including 17 Red List species but only a few seedlings of L. polyphyllus. The species composition of the seed bank matched distinct patterns of the three meadow types, but differed from the species composition of the current aboveground vegetation in a nonmetric multidimensional scaling ordination. While the influence of L. polyphyllus on the current vegetation was visible, no effects on the seed bank were apparent. L. polyphyllus had no influence on total seed density, seed density of typical mountain‐meadow species, or species numbers in the seed bank. Only the seeds of the Red List species were significantly related to the cover of L. polyphyllus. We conclude that the seed bank offers potential for active restoration of species‐rich mountain meadows, but species absent from the seed bank have to be added by other measures.  相似文献   

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Steven Wharry 《CMAJ》1996,155(1):112
The Society of Rural Physicians of Canada and the CMA are cooperating in the production of a new quarterly peer-reviewed journal that will focus on issues facing rural physicians. It will serve as a complement to existing primary care journals.  相似文献   

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Jill Rafuse 《CMAJ》1995,153(5):655-656
The CMA hopes the Commission of Inquity on the Blood System, chaired by Mr. Justice Horace Krever, “will restore faith in a system that is essential for the health and safety of all Canadians.” However, the cost implications any recommendations may have for the health care system must also be taken into consideration. The CMA made several recommendations in response to the commission''s interim report.  相似文献   

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