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81.
82.
W.F. Harris J.H. Darwin M.J. Newman 《Palaeogeography, Palaeoclimatology, Palaeoecology》1976,19(3):231-248
This paper uses the relative frequencies of occurrence of various types of pollen and spores to indicate the comparative temperatures under which Quaternary sediments accumulated in several locations in New Zealand. The application of association measures, and cluster and discriminant function analysis to such information is described and discussed.The analyses show that the types may be divided into groups whose members vary little with locality or with the statistical methods used to establish them. This stability suggests that anomalous dispersion effects are not a major influence. For some of these groups there is a similarity between the present-day climate of known pollen or spore sources and those of the corresponding groups at the time of deposition. The significant groups are used to summarise the results in pollen diagrams which are compared with similar diagrams for the discriminant function. It is also shown that the methods described assist in locating zone boundaries in a series of samples taken from a bore hole.The results obtained are relevant to the interpretation of samples in which southern beech (Nothofagus fusca type) is the most abundant tree pollen. 相似文献
83.
Marked dental disfigurement and abnormal tooth wear patterns were observed in black-tailed deer (Odocoileus hemionus columbianus) taken from an area near an industrial fluoride source in northwestern Washington. Fluoride levels in the bones of these deer were from 10 to 35 times higher than levels in the bones of normal animals. These levels are similar to those associated with fluorosis of cattle. 相似文献
84.
D J Etherington P B Newman R H Dainty S M Partridge 《Biochimica et biophysica acta》1976,445(3):739-752
Four extracellular proteolytic enzymes (I-IV) (EC 3.4.22.-) were identified in static cultures of Chromobacterium lividum (NCIB 10926) by agar gel electrophoresis and isoelectric focusing. Proteinases I-III were freed of non-enzymic protein by chromatography on TEAE-cellulose and CM-cellulose. The enzyme mixture was then fractionated in a pH gradient by isoelectric focusing. All three enzymes were shown to be heat-labile metallo-enzymes. Optimal activity occurred at pH 5.6 for enzyme I and at pH 6.2 for enzymes II and III. Remazolbrilliant Blue-hide powder was a sensitive substrate for these enzymes. Proteinase I was also shown to degrade haemoglobin and casein effectively, but not myoglobin, ovalbumin or bovine serum albumin. Proteinases I-III exhibited molecular weight values of 75 000, 72 000 and 67 000 by exclusion chromatography and 71 000 and 66 000 by sodium dodecyl sulphate-poly-acrylamide-gel electrophoresis for enzyme I and II, respectively. The amino acid compositions of enzymes I and II were somewhat similar. Proteinase I was inhibited by EDTA, 1,2-di(2-aminoethoxy)ethane-N,N,N',N'-tetraacetic activity. Mg2+ could substitute for Ca2+ or Mn2+ for Co2+. The interrelationship of proteinases I-III is discussed. 相似文献
85.
R J Newman 《BMJ (Clinical research ed.)》1976,2(6033):447-449
Metoprolol and acebutolol, two supposedly cardio-selective beta-adrenergic recptor blocking agents, were tested in healthy volunteers against propranolol, a non-selective drug, for their effect on blood glucose levels during insulin-induced hypoglycaemia. There was not significant difference between propranolol and metoprolol, which both potentiated the initial hypoglycaemic action of the insulin and delayed the return to normoglycaemia. Acebutolol, even though potentiating the initial hypoglycaemia, did not possess a significant delaying effect. A similar trial should be undertaken in diabetics to determine with certainty the safety of such drugs in diabetes mellitus. 相似文献
86.
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88.
The Development of Multi-epitope Vaccines: Epitope Identification, Vaccine Design and Clinical Evaluation 总被引:5,自引:0,他引:5
A. Sette B. Livingston D. McKinney E. Appella J. Fikes J. Sidney M. Newman R. Chesnut 《Biologicals》2001,29(3-4):271-276
We have developed efficient methods for epitope identification and vaccine design. Our process for epitope selection based on the combined use of motif analyses, binding assays and immunogenicity evaluations is described. We also describe how the projected population coverage and vaccine design can be optimized. Finally, it is discussed how vaccine potency is evaluated by immunogenicity and antigenicity assays. 相似文献
89.
The effects of minocycline on subgingival plaque samples from patients with chronic periodontitis were investigated in vitro. Minocycline concentrations as low as 1.0 μg/ml inhibited 95.7% of the cultivable bacteria in the samples but 256 μg/ml was necessary to inhibit all of the cultivable bacteria in the samples. Although up to 99.9% of bacteria in the plaque samples were killed by a 6 h exposure to 8.0 μg/ml of minocycline, large numbers of viable bacteria remained. These results imply that adequate reductions in the numbers of viable subgingival plaque bacteria are unlikely to occur after exposure to minocycline at concentrations attainable in gin-gival crevicular fluid after systemic administration. 相似文献
90.
Isolation of fatty acids covalently bound to the gastric mucus glycoprotein of normal and cystic fibrosis patients 总被引:6,自引:0,他引:6
A Slomiany B L Slomiany H Witas M Aono L J Newman 《Biochemical and biophysical research communications》1983,113(1):286-293
Covalently bound fatty acids were found in strictly purified and delipidated gastric mucus glycoprotein of normal and cystic fibrosis individuals. The susceptibility of this linkage to methanolic KOH and hydroxylamine treatment indicated the ester bond between fatty acids and glycoprotein. On the average, 2.9 nmol fatty acid/mg glycoprotein were found in normal samples, and 12.2 nmol/mg glycoprotein in samples derived from cystic fibrosis. In normal gastric mucus glycoprotein the covalently linked fatty acids consisted of hexadecanoate (47.0%), octadecanoate (22.0%), tetracosanoate (5.9%), octadecenoate (14.5%) and tetracosenoate (6.0%). In cystic fibrosis mucus glycoprotein the covalently bound fatty acids were comprised mainly of hexadecanoate (36.5%), octadecanoate (48.7%) and octadecenoate (8.6%). These data indicate that cystic fibrosis gastric mucus glycoprotein is highly acylated and perhaps this is the major defect of glycoproteins in this disease. 相似文献