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11.
Hammerstein P 《Journal of genetics》2005,84(1):7-12
This paper is written in memory of John Maynard Smith. In a brief survey it discusses essential aspects of how game theory
in biology relates to its counterpart in economics, the major transition in game theory initiated by Maynard Smith, the discrepancies
between genetic and phenotypic models in evolutionary biology, and a balanced way of reconciling these models. In addition,
the paper discusses modern problems in understanding games at the genetic level using the examples of conflict between endosymbionts
and their hosts, and the molecular interactions between parasites and the mammalian immune system. 相似文献
12.
Statistics for disinterested scientists. 总被引:11,自引:0,他引:11
This paper presents a brief introduction to some basic statistical tools and techniques with examples applied to biological data. Perhaps after becoming more familiar with statistics and more appreciative of their power in extracting information from data the previously fearful and skeptical researcher may be more inclined to make them an integral part of his research technique and also include them in his publications. For problems of greater difficulty, consultation at the early stages, preferably before undertaking the project, with a good biostatistician is suggested. 相似文献
13.
J. E. Cossentine E. K. Deglow L. B. M. Jensen A. M. R. Bennett 《Biocontrol Science and Technology》2004,14(7):691-699
Apophua simplicipes (Cresson) (Hymenoptera: Ichneumonidae) is a common parasitoid of the oblique banded leafroller, Choristoneura rosaceana (Harris) (Lepidoptera: Tortricidae) in organically managed apple orchards in the southern interior of British Columbia, Canada. The biological characteristics of a laboratory colony of A. simplicipes were studied. When held at 15 and 25°C and provided with honey water, individual females survived an average of 60.6±6.1 and 29.8±4.7 days, oviposited 196.7±50.7 and 326.6±51.3 eggs and parasitized a total of 163.4±40.4 and 229.4±35.8 hosts, respectively. Females oviposited into first through fourth instar oblique banded leafrollers, with significantly more parasitism occurring in the first two instars compared to the third and fourth instars. No parasitoid larvae survived past the first larval stage in parasitized fourth instar hosts. Apophua simplicipes did not parasitize larvae of three-lined leafroller, Pandemis limitata (Robinson) (Lepidoptera: Tortricidae) which is sympatric with oblique banded leafrollers in orchards in the southern interior of British Columbia. Female predation and host feeding from wounds on early instars of both leafroller species was observed under laboratory conditions. In addition, early instar hosts exited diet feeding sites in response to the probing activity of the ovipositing wasps. A similar escape reaction in the orchard may cause a leafroller larva to move away from its feeding site, making it more vulnerable to predation or movement off the tree. Apophua simplicipes larvae emerged from fifth and sixth instar hosts. Parasitized oblique banded leafroller hosts consumed significantly less meridic diet than unparasitized female larvae from fifth instar through to parasitoid emergence or leafroller pupation. Our laboratory results suggest that A. simplicipes may reduce field populations of oblique banded leafroller and decrease pest feeding damage. 相似文献
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In the 3- to 4-day embryonic avian limb bud, a unique zone of mesodermal tissue is located posteriorly at the junction of bud and body wall. Appropriately grafted to a host limb bud, it induces the formation of a supernumerary limb outgrowth from preaxial tissue and determines that its posterior side will face the graft. It is called the zone of polarizing activity (ZPA).When limb-bud mesoderm is isolated, dissociated, reaggregated centrifugally, jacketed in the mesoderm-free hull of another limb bud, and grown as a graft on a host embryo, the recombinant frequently forms a limb-like structure terminating in digits that fail to show differentiation with respect to the anteroposterior axis. When, however, a bit of ZPA tissue is implanted in the recombinant subjacent to the anterior or posterior margin of the ectoderm, the resulting outgrowth shows a characteristic anteroposterior order of digits that corresponds to the placement of the implant, regardless of its relationship with the anteroposterior axis of the ectoderm or of the host embryo.Dorsoventral differentials have been recognized only in limbs formed from reaggregated leg-bud mesoderm. The direction of the dorsoventral axis always corresponds to the original axis of the ectodermal jacket regardless of the orientation of the recombinant on the host. 相似文献
17.
John T. Dombrosky John A. Thomas Michael G. Mawhinney John W. Lloyd 《Life sciences》1973,13(7):795-804
Varying doses of morphine sulfate (10, 20 or 40 mg/kg daily × 10) were observed to suppress metabolic activities in the mouse prostate gland. Prostate gland fructose, an index of androgenic activity, was significantly reduced by these dose regimes of morphine (P < 0.01). Injections of morphine sulfate (20 mg/kg daily × 10) led to an inhibitition in the synthesis of both fructose?14C and sorbitol?14C from glucose?14C by the prostate gland, part of which may have been due to decreased uptake of glucose by the gland. The assimilation of 2-deoxyglucose?14C by the prostate was also reduced by morphine treatment. The actions of morphine (2 × 10?3M) on the metabolism of radioactive glucose by the mouse prostate gland likewise revealed a significant reduction in the formation of sorbitol?14C, but no decrease in fructose?14C formation. These results indicate that both the and actions of morphine can inhibit fructose metabolism in the prostate gland. 相似文献
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The morphological characters of Pterophyllum guizhouense sp. nov. were reported and those of P. astartense Harris were supplied and emended. Meanwhile, the significance of cuticle characters chosen in the identification of fossil plants was also discussed. 相似文献
20.
Among paintings of birds thought to have been bought in 1663 in Nuremberg by Francis Willughby, and now housed in Nottingham
University library, is the painting of a bird called Jangle de Languedoc. Unlike some of the other drawings, this particular
one was never used by Ray in his Ornithology of Francis Willughby (1678), who had difficulty in identifying the bird. We show here that this painting was not bought in Nuremberg, but that it was
obtained by Ray from Sir Thomas Crew, during his stay in Montpellier in 1665. Furthermore, had Ray looked at Gessner (Historiae animalium liber III qui est de avium natura. Christophus Froschoverus, Tiguri, 1555), Aldrovandi (Ornithologiae, tomus alter. Bononiae, apud Franciscum de Franciscis Senensem, 1600), Jonston (Historiae naturalis de avibus libri VI. Matthaeus Merianus, Frankfurt, 1650) and mostly at Charleton (Gualteri Charletoni Exercitationes de Differentiis & Nominibus Animalium. Theatro Sheldoniano, Oxford, 1677), he would have been able to identify the bird of the painting as alchata or “angel”, specifically a pintailed sandgrouse,
Pterocles alchata. 相似文献