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141.
Graham Oppy 《Biology & philosophy》1996,11(4):519-534
There seems to be a widespread conviction — evidenced, for example, in the work of Mackie, Dawkins and Sober — that it is Darwinian rather than Humean considerations which deal the fatal logical blow to arguments for intelligent design. I argue that this conviction cannot be well-founded. If there are current logically decisive objections to design arguments, they must be Humean — for Darwinian considerations count not at all against design arguments based upon apparent cosmological fine-tuning. I argue, further, that there are good Humean reasons for atheists and agnostics to resist the suggestion that apparent design — apparent biological design and/or apparent cosmological fine-tuning — establishes (or even strongly supports) the hypothesis of intelligent design. 相似文献
142.
A crown rot disease in wheat caused by the fungusFusarium graminearum Schw. Group 1 is a widespread problem in chronically Zn-deficient Australian soils. A link between crown rot and Zn deficiency
was established by Sparrow and Graham (1988). This paper reports a test of a further hypothesis, that wheat genotypes more
efficient at extracting zinc from low-zinc soils are more resistant to infection by this pathogen. Three wheat cultivars (Excalibur,
Songlen and Durati) of differential Zn efficiency were tested at three zinc levels (0.05, 0.5 and 2.0 mg Zn kg−1 of soil) and three levels ofF. graminearum S. Group 1 inoculum (0.1 g and 0.3 g kg−1 live chaff-inoculum and control having 0.1 g kg−1 dead chaff inoculum). Six weeks after sowing dry matter production of shoots and roots was decreased byFusarium inoculation at 0.05 mg and 0.5 mg kg−1 applied Zn.Fusarium inoculum at 0.1 g was as effective as 0.3 g kg−1 for infection and decreasing dry matter. The infection at the basal part of culm decreased significantly by increasing the
rate of Zn application. Excalibur, a Zn-efficient cultivar (tolerant to Zn deficiency) produced significantly more shoot and
root dry matter, and showed less disease infection compared with Zn-inefficient cultivars (Durati and Songlen) at low (0.05
mg Zn kg−1 soil) and medium (0.5 mg Zn kg−1 soil) Zn fertilization rates. Higher rate of Zn fertilization (2.0 mg Zn kg−1 soil) reduced the disease level in Durati to the level of Excalibur but the disease level of Songlen was still high, indicating
its high Zn requirement and or sensitivity to crown rot. The data on Zn uptake show that Excalibur, being Zn-efficient, was
able to scavenge enough Zn from Zn-deficient soil, we suggest that besides sustaining growth Excalibur was able to build and
maintain resistance to the pathogen; inefficient cultivars needed extra Zn fertilization to achieve performance comparable
to that of Excalibur. The present study indicates that growing Zn-efficient cultivars of wheat along with judicious use of
Zn fertilizer in Zn-deficient areas where crown rot is a problem may sustain wheat production by reducing the severity of
the disease as well as by increasing the plant vigour through improved Zn nutrition. ei]Section editor: R Rodriques-Kalana 相似文献
143.
FGFR2 exon IIIa and IIIc mutations in Crouzon, Jackson-Weiss, and Pfeiffer syndromes: evidence for missense changes, insertions, and a deletion due to alternative RNA splicing. 总被引:8,自引:0,他引:8 下载免费PDF全文
G. A. Meyers D. Day R. Goldberg D. L. Daentl K. A. Przylepa L. J. Abrams J. M. Graham Jr M. Feingold J. B. Moeschler E. Rawnsley A. F. Scott E. W. Jabs 《American journal of human genetics》1996,58(3):491-498
Fibroblast growth factor receptor 2 (FGFR2) mutations have been associated with the craniosynostotic conditions Crouzon, Jackson-Weiss, and Pfeiffer syndromes. Previously, mutations were described in the exons IIIa and IIIc, which form the extracellular, third immunoglobulin-like domain (IgIII) and adjacent linker regions, both of which are normally involved in ligand binding. For all three conditions, mutations were found in exon IIIc. Only in Crouzon syndrome were mutations identified in exon IIIa. In this study, 39 cases with one of these three conditions were screened for exon IIIa or IIIc mutations. Eleven mutations are reported in 17 unrelated cases. Mutations in exon IIIa are identified for not only Crouzon but also Jackson-Weiss and Pfeiffer syndromes. Four mutations in either exon IIIa or exon IIIc reported only in Crouzon syndrome are present also in one of the other two syndromes. Two insertions, one in exon IIIa in a Crouzon syndrome patient and the other in exon IIIc in a Pfeiffer syndrome patient, were observed. The latter mutation has the same alternative RNA splicing effect as a reported synonymous mutation for Crouzon syndrome. A missense mutation was detected in one Pfeiffer syndrome family in which two members had craniosynostosis without limb anomalies. The inter- and intrafamilial variability in expression of FGFR2 mutations suggests that these three syndromes, presumed to be clinically distinct, are instead representative of a spectrum of related craniosynostotic and digital disorders. 相似文献
144.
145.
Joan E. Vickers Glenn C. Graham Robert J. Henry 《Plant Molecular Biology Reporter》1996,14(4):363-368
Amplification of thebar gene usingTaq DNA polymerase in PCR is often not successful, possibly due tobar's high GC content. We describe a PCR protocol in which reliable amplification at a sensitivity of one gene copy per genome
(in this study, barley) present in the reaction was achieved using a novel pair of primers and Expandtm High Fidelity DNA polymerase mix (Boehringer Mannheim). This method should allow for rapid screening of plants putatively
transformed withbar. 相似文献
146.
Caesium accumulation by microorganisms: uptake mechanisms,cation competition,compartmentalization and toxicity 总被引:4,自引:0,他引:4
Simon V. Avery 《Journal of industrial microbiology & biotechnology》1995,14(2):76-84
Summary The continued release of caesium radioisotopes into the environment has led to a resurgence of interest in microbe-Cs interactions. Caesium exists almost exclusively as the monovalent cation Cs+ in the natural environment. Although Cs+ is a weak Lewis acid that exhibits a low tendency to form complexes with ligands, its chemical similarity to the biologically essential alkali cation K+ facilitates high levels of metabolism-dependent intracellular accumulation. Microbial Cs+ (K+) uptake is generally mediated by monovalent cation transport systems located on the plasma membrane. These differe widely in specificity for alkali cations and consequently microorganisms display large differences in their ability to accumulate Cs+; Cs+ appears to have an equal or greater affinity than K+ for transport in certain microorganisms. Microbial Cs+ accumulation is markedly influenced by the presence of external cations, e.g. K+, Na+, NH4
+ and H+, and is generally accompanied by an approximate stoichiometric exchange for intracellular K+. However, stimulation of growth of K+-starved microbial cultures by Cs+ is limited and its has been proposed that it is not the presence of Cs+ in cells that is growth inhibitory but rather the resulting loss of K+. Increased microbial tolerance to Cs+ may result from sequestration of Cs+ in vacuoles or changes in the activity and/or specificity of transport systems mediating Cs+ uptake. The precise intracellular target(s) for Cs+-induced toxicity has yet to be clearly defined, although certain internal structures, e.g. ribosomes, become unstable in the presence of Cs+ and Cs+ is known to substitute poorly for K+ in the activation of many K+-requiring enzymes. 相似文献
147.
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150.
Peter E. Molloy Barbara M. Graham Pauline M. Cupit Steven D. Grant Andrew J. R. Porter Charles Cunningham 《Molecular biotechnology》1995,4(3):239-245
This work describes protocols for the production of single-chain antibody and T-cell receptor fragments inE. coli. A choice of methods is given for the purification of the recombinant fragments that rely on the use of either immunoaffinity
or metal chelate affinity chromatography. The TCR fragments may have to be denatured and refolded before the fragments attain
their proper conformation. 相似文献