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1.
M A Chamberlain 《BMJ (Clinical research ed.)》1985,290(6480):1449-1450
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G Chamberlain 《BMJ (Clinical research ed.)》1991,302(6792):1592-1596
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The fossil evidence of the “robust” australopithecines is reviewed with an emphasis on the taxonomic divisions and evolutionary relationships among this group of hominids. The hypodigms of A. robustus, A. crassidens and A. boisei are described, and the significance of morphological variation within and between these species is assessed. Phylogenetic relationships among the “robust” australopithecines are examined using maximum parsimony analysis, and evolutionary scenarios are evaluated in the light of recent discoveries in East Africa. 相似文献
5.
Thomas J. Weissling Lance J. Meinke Donald Trimnell Krista L. Golden 《Entomologia Experimentalis et Applicata》1989,53(3):219-228
The concept of encapsulating semiochemicals into a starch matrix is being studied for potential use in corn rootworm (CRW) management programs. During 1987, experiments were conducted to determine: 1) If volatile plant-derived Diabrotica spp. attractants could be encapsulated in a starch borate matrix (SBM), and 2) If various SBM-semiochemical formulations would attract Diabrotica species over time in field corn. Chemical analyses of fresh SBM formulations indicated that indole, estragole, veratrole, phenylacetaldehyde, and trans-anethole were not retained during formulation but trans-cinnamaldehyde, Beta-ionone, 1,2,4,-trimethoxybenzene, eugenol and isugenol were successfully encapsulated. Encapsulated semiochemical formulations were made into 20 mesh granules, placed in Pherocon ® 1C traps that were tied to corn plants, and sampled for CRW adults every 4 days from 11 July to 8 September. Field data indicated that encapsulated semiochemicals were retained in the SBM for varying lengths of time and were released at rates attractive to CRW adults. A two-component mixture of trans-cinnamaldehyde and 1,2,4-trimethoxybenzene was the most effective formulation tested; however, no formulation was effective during corn silking and pollination. Although seasonal variation in CRW response could limit the usefulness of some plant-derived semiochemicals, the starch matrix concept may be useful as a delivery system for semiochemicals and may have potential as a tool that could be used in the development of new more biorational CRW management programs.
Résumé Le programme expérimental de 1987 était destiné à déterminer: 1) si les substances dérivées de végétaux et attractives pour Diabrotica pouvaient être encapsulées dans de l'amidon additionné d'acide borique; 2) si différentes formules attireraient les différentes espèces de Diabrotica dans un champ de maïs.L'indol, l'estragol, le vératrol, le phénylacétaldéhyde et le trans-anéthol n'ont pas été retenus, tandis que le trans-cinnamaldéhyde, la \-ionone, le 1,2,4-triméthobenzène, l'eugénol et l'isugénol ont été encapsulés avec succès dans des pièges attachés à des pieds de maïs (les détails techniques sont fournis). Les pièges ont été relevés tous les 4 jours du 11 juillet au 8 septembre. Les résultats montrent que les substances allélochimiques sont conservées dans la capsule pendant des durées variables et libérées à des concentrations attractives pour les Diabrotica adultes. Un mélange de trans-cinnamaldéhyde et de 1,2,4,-triméthoxybenzène a été la formule la plus efficace, à l'exception des périodes de formation des barbes et du pollen, où aucune formule n'a été attractive. Bien que la variation saisonnière des réactions de Diabrotica limite l'utilisation des substances allélochimiques d'origine végétale, la capsule d'amidon peut être employée pour libérer des substances allélochimiques et constitue un outil potentiel pour la mise au point d'une méthode plus rationnelle de lutte contre Diabrotica.相似文献
6.
Complex glycerol kinase deficiency (CGKD) is a contiguous gene syndrome consisting of glycerol kinase deficiency together with Duchenne muscular dystrophy (DMD), congenital adrenal hypoplasia, and/or Aland Island eye disease. Deletion mapping of genomic DNA from patients with CGKD was carried out and allowed definitive ordering of loci DXS28 (C7), DXS68 (L1-4), and DXS67 (B24). Most reports have placed DXS68 centromeric to DXS28 and DXS67 on the basis of the initial mapping of the Iowa patient 3, but others have presented evidence consistent with the placement of DXS28 telomeric to DXS68 and DXS67. Through the use of DNA from CGKD patients with a variety of genomic deletions, this controversy is resolved and the order Xcen...DMD-DXS28-DXS68-DXS67...pter is definitively demonstrated. 相似文献
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J. M. Addington-Hall L. D. MacDonald H. R. Anderson J. Chamberlain P. Freeling J. M. Bland J. Raftery 《BMJ (Clinical research ed.)》1992,305(6865):1317-1322
OBJECTIVES--To measure effects on terminally ill cancer patients and their families of coordinating the services available within the NHS and from local authorities and the voluntary sector. DESIGN--Randomised controlled trial. SETTING--Inner London health district. PATIENTS--Cancer patients were routinely notified from 1987 to 1990. 554 patients expected to survive less than one year entered the trial and were randomly allocated to a coordination or a control group. INTERVENTION--All patients received routinely available services. Coordination group patients received the assistance of two nurse coordinators, whose role was to ensure that patients received appropriate and well coordinated services, tailored to their individual needs and circumstances. MAIN OUTCOME MEASURES--Patients and carers were interviewed at home on entry to the trial and at intervals until death. Interviews after bereavement were also conducted. Outcome measures included the presence and severity of physical symptoms, psychiatric morbidity, use of and satisfaction with services, and carers'' problems. Results from the baseline interview, the interview closest to death, and the interview after bereavement were analysed. RESULTS--Few differences between groups were significant. Coordination group patients were less likely to suffer from vomiting, were more likely to report effective treatment for it, and less likely to be concerned about having an itchy skin. Their carers were more likely to report that in the last week of life the patient had had a cough and had had effective treatment for constipation, and they were less likely to rate the patient''s difficulty swallowing as severe or to report effective treatment for anxiety. Coordination group patients were more likely to have seen a chiropodist and their carers were more likely to contact a specialist nurse in a night time emergency. These carers were less likely to feel angry about the death of the patient. CONCLUSIONS--This coordinating service made little difference to patient or family outcomes, perhaps because the service did not have a budget with which it could obtain services or because the professional skills of the nurse-coordinators may have conflicted with the requirements of the coordinating role. 相似文献
9.
Michael I. Lerman Farida Latif Gladys M. Glenn Lambert N. Daniel Hiltrud Brauch Shigeto Hosoe Krista Hampsch John Delisio Mary Lou Orcutt O. Wesley McBride Karl-Heinz Grzeschik Takashi Takahashi John Minna Patrick Anglard W. Marston Linehan Berton Zbar 《Human genetics》1991,86(6):567-577
Summary A collection of 2,000 lambda phage-carrying human single-copy inserts (> 700 bp) were isolated from two chromosome-3 flow-sorted libraries. The single-copy DNA fragments were first sorted into 3p and 3q locations and about 700 3p fragments were regionally mapped using a deletion mapping panel comprised of two humanhamster and two-human-mouse cell hybrids, each containing a chromosome 3 with different deletions in the short arm. The hybrids were extensively mapped with a set of standard 3p markers physically localized or ordered by linkage. The deletion mapping panel divided the short arm into five distinct subregions (A-E). The 3p fragments were distributed on 3p regions as follows: region A, 26%; B, 31%; C, 4%; D, 4% and E, 35%. We screened 300 single-copy DNA fragments from the distal part of 3p (regions A and B) with ten restriction endonucleases for their ability to detect restriction fragment length polymorphisms (RFLPs). Of these fragments 110 (36%) were found to detect useful RFLPs: 35% detected polymorphisms with frequency of heterozygosity of 40% or higher, and 25% with frequency of 30% or higher. All polymorphisms originated from single loci and most of them were of the base pair substitution type. These RFLP markers make it possible to construct a fine linkage map that will span the distal part of chromosome 3p and encompasses the von Hippel-Lindau disease locus. The large number of single-copy fragments (2,000) spaced every 100–150 kb on chromosome 3 will make a significant contribution to mapping and sequencing the entire chromosome 3. The 300 conserved chromosome 3 probes will increase the existing knowledge of man-mouse homologies. 相似文献
10.
D. A. Chamberlain R. J. White M. R. Howard T. W. Smith 《BMJ (Clinical research ed.)》1970,3(5720):429-432
Plasma digoxin concentrations were measured by radioimmunoassay in 116 patients with atrial fibrillation on long-term oral treatment with the drug, and in 23 patients with digoxin toxicity. The mean concentrations were 1·4 ng./ml. and 3·1 ng./ml., respectively. Though an overlap occurred between the therapeutic and toxic ranges, toxicity is unlikely to occur below a level of 2 ng./ml. Plasma concentration showed a poor correlation with resting heart rate during atrial fibrillation. In patients with good renal function, however, a significant correlation was found between oral dose and plasma concentration. No evidence was obtained for increased sensitivity to therapeutic concentrations of the drug in elderly subjects, but the doses required to achieve these concentrations tended to be less than in younger patients. 相似文献