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641.
642.
Christel Dtsch 《Journal of morphology》1986,189(1):25-43
High-speed cinematography shows that Suncus murinus (Crocidurinae) masticates fast (mean 5.5, 5–10 masticatory cycles per sec). Their grasping behavior is not stereotyped. The unilateral mandibular movements combine vertical, anteroposterior, and lateral displacements; and any masticatory sequence may include crushing, repositioning, shearing, and grinding components. Size and consistency of food influence the duration of individual chewing cycles. As food is transferred to the new working side, the chewing direction reverses, either near maximum closure or near maximum opening. An unfused mandibular symphysis permits tilting movements of the two halves of the mandible. Food may be squeezed between the lower incisors. The working side tilts outward during closing; this may improve shearing or grinding action. The closing phase is posteriorly directed. Thus, the masticatory movements of these shrews differ from those that have been described in many other mammals. 相似文献
643.
The monoclonal antibody Z-3Bl (Schneider-Poetsch et al., Planta 173 [1988] 61–72) was used to localize phytochrome in the Mougeotia cell by indirect immunofluorescence. The antibody detected a protein of about 110 kD in the immunoblot. Immunofluorescence indicated abundant phytochrome throughout the cytoplasm. In Mougeotia, a large cytoplasmic pool of phytochrome is presumably in equilibrium with a probably reactant-bound Pfr-pool at the plasmalemma, the latter being responsible for the physiological response. 相似文献
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Daily examinations of monocyte blood counts in healthy individuals indicated the presence of a monocyte cycle. The cycle length was between 3 and 6 days. The predominant period was 5 days. A similar oscillation frequency resulted from a computer simulation of a feedback loop which linked the blood monocyte compartment (controlled variable) to the stem cell differentiation rate (controlling variable). 相似文献
647.
Christel Munk 《Pal?ontologische Zeitschrift》1979,53(3-4):220-229
Heteromorph Ammonites of the generaParapatoceras Spath,Paracuariceras Schindewolf undAcuariceras Spath from the Lower Callovian (“Macrocephalen-Schichten” of the Northern Franconian Alb are described. The species of the genusParapatoceras Spath are dominant. New finds of the generaParacuariceras Schindewolf andAcuariceras Spath show that their first occurence is in the Lower Callovian. The optimal biotope of the heteromorphs with vagile benthonic mode of life was probably, similar to the Swabian Dogger, in stillwater areas. 相似文献