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41.
D Scott S M Galloway R R Marshall M Ishidate D Brusick J Ashby B C Myhr 《Mutation research》1991,257(2):147-205
42.
R. R. Hill Jr. F. L. Kolb H. G. Marshall 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1991,81(1):79-82
Summary Parameters estimated from a Gardner-Eberhart analysis of the F2 generation of a six-parent diallel in oats (Avena sativa L.) were used to compare methods for predicting the performance of F3 row plots. The prediction methods were: (1) individual F2 plant performance (F2I), (2) parent average plus F2 plot deviations (PF2), (3) parent average plus weighted F2 plot deviations (PF2P), (4) best linear unbiased prediction (BLUP) of parent average plus F2 plot deviations (BPF2), and (5) BLUP plus weighted F2 deviations (BF2). The F2 single-plant traits used for prediction were biological yield to predict F3 biological yield, whole plant and primary tiller grain yield for prediction of F3 grain yield, and whole plant and primary tiller harvest index (HI) to predict F3 HI. Prediction methods were evaluated by correlations between predicted and observed F3 performance. Prediction methods and traits for which correlations were greater than for F2I included: BF2 for biological yield, PF2, PF2P and BF2 for whole plant grain yield, PF2, BPF2, and BF2 for primary tiller grain yield. None had a correlation significantly greater than F2I for either measure of HI, where heritability was large. PF2 is the recommended method for traits with low heritability because of its simplicity and because it had the largest or nearly the largest correlation for each of the yield traits. F2I is the recommended method for traits with larger heritability.Contribution No. 8821 of the U.S. Regional Pasture Research LaboratoryDeceased 相似文献
43.
Piero Pollesello Renato Toffanin Erminio Murano Roberto Rizzo Sergio Paoletti Bjarne J. Kvam 《Journal of applied phycology》1992,4(2):149-155
Lipid extracts of the red algaGracilaria longa were studied by1H- and13C-NMR spectroscopy. Peaks in the13C-NMR spectra attributable to sterols, chlorophylls and carotenoids allowed free and acylated cholesterol, chlorophylla and lutein to be identified as the most abundant components of these classes. A content of 0.5 ± 0.1 μmoles of total cholesterol/g
wet alga was estimated from the1H-NMR spectrum, which also allowed the determination of the phosphatidylcholine/total lipid molar ratio (9.5 ± 0.5%). The13C-NMR spectroscopic experiments provided information on the position of the double bonds on the fatty acid residues. A comparison
between NMR spectra of lipid extracts obtained for wet and dried alga showed that the alga undergoes both a dramatic peroxidation
and some glycolipid degradation during the drying process. 相似文献
44.
The AXB and BXA set of recombinant inbred mouse strains 总被引:1,自引:1,他引:0
Jan D. Marshall Jian-Long Mu Yin-Chai Cheah Muriel N. Nesbitt Wayne N. Frankel Beverly Paigen 《Mammalian genome》1992,3(12):669-680
The recombinant inbred (RI) set of strains, AXB and BXA, derived from C57BL/6J and A/J, originally constructed and maintained at the University of California/San Diego, have been imported into The Jackson Laboratory and are now in the 29th to 59th generation of brother-sister matings. Genetic quality control testing with 45 proviral and 11 biochemical markers previously typed in this RI set indicated that five strains had been genetically contaminated sometime in the past, so these strains have been discarded. The correct and complete strain distribution patterns for 56 genetic markers are reported for the remaining RI strain set, which consists of 31 living strains and 8 extinct strains for which DNA is available. Two additional strains, AXB 12 and BXA 17, are living and may be added to the set pending further tests of genetic purity. The progenitors of this RI set differ in susceptibility to 27 infectious diseases as well as atherosclerosis, obesity, diabetes, cancer, cleft palate, and hydrocephalus. Thus, the AXB and BXA set of RI strains will be useful in the genetic analysis of several complex diseases. 相似文献
45.
46.
OBJECTIVES--To follow up severely mentally ill residents of hostels for the homeless to determine their social and psychiatric outcome. DESIGN--Follow up at 18 months of hostel residents previously assessed with psychiatric and behavioural measures. SETTING--Two Oxford hostels for the homeless. SUBJECTS--48 hostel residents previously identified as disabled by mental illness. MAIN OUTCOME MEASURES--Current housing, admissions to psychiatric hospital, violent or antisocial behaviour, and score on standardised behavioural rating. RESULTS--45 of the 48 residents were traced. 27 had remained in the hostels; only 10 had been rehoused, mainly in bedsits or with their families. 16 had a poor outcome as judged by death (four subjects), lengthy hospital readmission (two), marked deterioration in behaviour (six), sleeping rough (one), or disappearance (three). CONCLUSION--More effort is needed to provide suitable housing for homeless mentally ill people. 相似文献
47.
The GTPase stimulatory activities of the neurofibromatosis type 1 and the yeast IRA2 proteins are inhibited by arachidonic acid. 总被引:3,自引:1,他引:2
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M Golubi K Tanaka S Dobrowolski D Wood M H Tsai M Marshall F Tamanoi D W Stacey 《The EMBO journal》1991,10(10):2897-2903
Three proteins, GTPase activating protein (GAP), neurofibromatosis 1 (NF1) and the yeast inhibitory regulator of the RAS-cAMP pathway (IRA2), have the ability to stimulate the GTPase activity of Ras proteins from higher animals or yeast. Previous studies indicate that certain lipids are able to inhibit this activity associated with the mammalian GAP protein. Inhibition of GAP would be expected to biologically activate Ras protein. In these studies arachidonic acid is shown also to inhibit the activity of the catalytic fragments of the other two proteins, mammalian NF1 and the yeast IRA2 proteins. In addition, phosphatidic acid (containing arachidonic and stearic acid) was inhibitory for the catalytic fragment of NF1 protein, but did not inhibit the catalytic fragments of GAP or IRA2 proteins. These observations emphasize the biochemical similarity of these proteins and provide support for the suggestion that lipids might play an important role in their biological control, and therefore also in the control of Ras activity and cellular proliferation. 相似文献
48.
Nigel A. S. Taylor James D. Cotter Stephen N. Stanley Robert N. Marshall 《European journal of applied physiology and occupational physiology》1991,62(2):116-121
Technical limitations of some isokinetic dynamometers have called into question the validity of some data on human muscle mechanics. The Biodex dynamometer has been shown to minimize the impact artefact while permitting automatic gravity correction. This dynamometer was used to study quadriceps muscle torque and power generation in elite power (n = 6) and elite endurance (n = 7) athletes over 12 randomly assigned isokinetic velocities from 30 degrees.s-1 to 300 degrees.s-1. The angle at peak torque varied as a negative, linear function of angular velocity, with the average angle across test velocities being 59.5 degrees (SD 10.2 degrees). Power athletes developed greater peak torque at each angular velocity (P less than 0.05) and experienced a 39.7% decrement in torque over the velocity range tested. Endurance athletes encountered a 38.8% decline in peak torque. Torques measured at 60 degrees of knee flexion followed a similar trend in both groups; however the greatest torques were recorded at 60 degrees.s-1 rather than at 30 degrees.s-1. Leg extensor muscle power increased monotonically with angular velocity in both power (r2 = 0.728) and endurance athletes (r2 = 0.839); however these curves diverged significantly so that the power athletes produced progressively more power with each velocity increment. These inter group differences probably reflected a combination of natural selection and training adaptation. 相似文献
49.
C3 allotyping has been performed on 424 Australian women, 203 with normotensive pregnancies, 161 with hypertensive noneclamptic pregnancies and 60 eclamptic women. The frequency of women heterozygous for 'rare' C3 alleles was 1% in the normotensive women and 3.7% in the hypertensive group. Three out of 25 (12%) of the women with proteinuric hypertension in pregnancy carried 'rare' C3 alleles. This suggested the hypothesis that pre-eclampsia/eclampsia is associated with a higher frequency of rare alleles. The sample of 60 eclamptic women collected to test the hypothesis had no rare alleles, refuting the hypothesis. The frequency of the common (C3F, C3S) alleles did not differ significantly between the three groups. We conclude that there is no evidence for any association between susceptibility to eclampsia and allotypes of the C3 complement component. 相似文献
50.
A highly sensitive and simple method to enhance detection of glycoproteins resolved by either one- or two-dimensional polyacrylamide gel electrophoresis is described. The method is a modification of the procedure described by D. Fargeaud et al. (D. Fargeaud, J. C. Benoit, F. Kato, and G. Chappuis (1984) Arch. Virol. 80, 69-82) that uses concanavalin A conjugated with fluorescein isothyocyanate to detect the carbohydrate moiety of glycoproteins. Briefly, the electrophoresed gel is exposed to the fluorescent lectin, thoroughly washed, and sequentially transferred to 50% methanol in deionized water and to absolute methanol. The result is an abrupt dehydration of the gel which turns evenly white and stiff. At least a twofold enhancement of fluorescence is obtained as detected by exposing the treated gel to an appropriate uv source. The sensitivity of the procedure allows us to detect purified immunoglobulin molecules by their carbohydrate content in the range of 0.2 microgram of total protein. The specificity of the detection is demonstrated by a comparison with the corresponding polypeptide profile obtained by silver nitrate staining of the gel. 相似文献