stem from|源于 #每日一词#

• Statistical issues stem from the choice of molecular marker type and marker set used, in addition to sampling strategy. (Wilson, Ferguson, 2002)
• For conifers, these limitations stem from the large, repetitive genomes that make gene cloning and chromosome walking very difficult (Neale and Williams 1991), and from the large physical distances between genetically mapped loci, probably exceeding 4000 kilobases per centimorgan (cf. (Strauss, Lande, Namkoong, 1992)
• Many of the applications and simplifications which stem from the definitions and concepts developed herein for groups or subdivisions of populations remain to be elaborated. (Cockerham, 1967)
• Seminal work has illuminated the possibility that many of the adaptive responses by forest trees to their environments, however, may stem from epigenetic effects ( Johnsen et al. (Eckert et al., 2009)