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21.
Julio M. Singer Frederico Z. Poleto Patrícia Rosa 《Biometrical journal. Biometrische Zeitschrift》2004,46(4):460-473
We compare two models for the analysis of repeated ordinal categorical data: the classical parametric model for means of scores assigned to the categories of the response variable and a nonparametric model based on relative effects derived from the marginal distribution functions of the response. An example in the field of Dentistry is used to illustrate and to compare the models. We also consider a simulation study to evaluate the type‐I error rates and the power of tests under both models in a balanced design setup. The simulation results suggest that both approaches behave similarly for equally spaced scores but may perform differently otherwise. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
22.
After reviewing the use of non-human primates of the Old and New Worlds for human malaria research, we concluded that another experimental animal which is easily available to use and possible to rear indoors is needed. Thus, we studied the susceptibility of the marmoset Callithrix penicillata to Plasmodium falciparum erythrocytic infections. The marmosets received various P. falciparum human isolates, directly from a patient and from continuous cultures. The Palo Alto strain, which has been adapted to the night monkey Aotus trivirgatus and further maintained in the squirrel monkey Saimiri sciureus was also used. In a total of 20 marmosets we performed 31 inoculations, with 10(5) to 10(9) parasites, intraperitoneally, intracardiacly or intravenously. Blood samples from each animal were examined daily up to day 90 post-inoculation. None of the intact marmosets developed patent infections. Four out of 19 C. penicillata, previously splenectomized, showed circulating parasites for up to five days after intravenous inoculation with the Palo Alto strain, becoming negative thereafter. Neither the addition to the simian diet of p-aminobenzoic acid, essential for the parasite metabolism, nor drug-immunosuppression, improved the marmoset susceptibility to P. falciparum. 相似文献
23.
W. L. C. Vaz J. Stümpel D. Hallmann A. Gambacorta M. De Rosa 《European biophysics journal : EBJ》1987,15(2):111-115
Fluorescence recovery after photobleaching was used to investigate the translational diffusion of a fluorescent derivative of a membrane-spanning lipid in L
phase multibilayers of 1-palmitoyl-2-oleoylphosphatidylcholine prepared in water and in glycerol. The translational diffusion coefficient in hydrated bilayers (D
w) ranged between 2 and 5x10–8 cm2/s and in glycerinated bilayers (D
g) the range was between 3 and 24×10–10 cm2/s between 10° and 40°C. These results are discussed in terms of models for diffusion in membranes. 相似文献
24.
25.
The primary structure of human secretogranin I (chromogranin B): comparison with chromogranin A reveals homologous terminal domains and a large intervening variable region. 总被引:18,自引:7,他引:11 下载免费PDF全文
U M Benedum A Lamouroux D S Konecki P Rosa A Hille P A Baeuerle R Frank F Lottspeich J Mallet W B Huttner 《The EMBO journal》1987,6(5):1203-1211
26.
Fragile sites,chromosome evolution,and human neoplasia 总被引:12,自引:0,他引:12
Rosa Miró Inmaculada Concepción Clemente Carmen Fuster José Egozcue 《Human genetics》1987,75(4):345-349
Summary In a study of the possible relationship between human fragile sites, chromosomal rearrangements related to neoplasia, and chromosome regions involved in evolutionary changes, we have found that 17 fragile sites related to cancer, 15 fragile sites not related to cancer, and 17 non-fragile regions also related to human malignancy correspond or are close to bands involved in rearrangements that have taken place during chromosomal evolution in primates. 相似文献
27.
Pablo Rodriguez-Palenzuela Joaquin Royo Luis Gómez Rosa Sánchez-Monge Gabriel Salcedo José Luis Molina-Cano Francisco Garcia-Olmedo Pilar Carbonero 《Molecular & general genetics : MGG》1989,219(3):474-479
Summary A cDNA encoding trypsin inhibitor CMe from barley endosperm has been cloned and characterized. The longest open reading frame of the cloned cDNA codes for a typical signal peptide of 24 residues followed by a sequence which is identical to the known amino acid sequence of the inhibitor, except for an Ile/Leu substitution at position 59. Southern blot analysis of wheat-barley addition lines has shown that chromosome 3H of barley carries the gene for CMe. This protein is present at less than 2%–3% of the wild-type amount in the mature endosperm of the mutant Risø 1508 with respect to Bomi barley, from which it has been derived, and the corresponding steady state levels of the CMe mRNA are about I%. One or two copies of the CMe gene (synonym Itc1) per haploid genome have been estimated both in the wild type and in the mutant, and DNA restriction patterns are identical in both stocks, so neither a change in copy number nor a major rearrangement of the structural gene account for the markedly decreased expression. The mutation at the lys 3a locus in Risø 1508 has been previously mapped in chromosome 7 (synonym 5H). A single dose of the wild-type allele at this locus (Lys 3a) restores the expression of gene CMe (allele CMe-1) in chromosome 3H to normal levels. 相似文献
28.
Summary A basic procedure was developed to produce high-protein amaranth flour (HPAF) using a commercial preparation of heat-stable alpha-amylase. Slurries (20%, w/v) of gelatinized whole flour were liquefied at 70 and 90°C, pH 6.5, 0.1% (w/v) enzyme concentration and 30 min hydrolysis time. Protein content of raw flour was increased from 15 to 29.6 or 39.3% at liquefaction temperatures of 70 or 90°C, respectively. Some physicochemical and functional properties of HPAF were assessed. HPAF might be used as a dry milk extender. 相似文献
29.
C. E. Scanlon N. R. Chalmers M. A. O. Monteiro da Cruz 《International journal of primatology》1989,10(2):123-136
Three wild groups of common marmoset, Callithrix jacchus jacchus,in north-east Brazil, of approximately similar size, had home ranges between 2.5 and 6.5 ha. But their core areas were similar
in size between 1.0 and 1.5 ha, with a monthly area of heavy use between 1.1 and 1.6 ha. The groups were selective in the
use of their home ranges, even though they were small: they used some areas heavily and others lightly. The core areas had
higher densities of trees that produced gum exudates than did other parts of the home ranges. Our data suggest that a group
of marmosets in this habitat may require a minimum of about 50 gum trees in its home range at a minimum density of about 50
trees/ha. In addition, the animals require suitable trees in which to sleep. We suggest that patches of forest with these
desirable properties remain relatively fixed in size and location over the years and that individual animals are constantly
in flux between them. 相似文献
30.
Human bisphosphoglycerate mutase expressed in E coli: purification, characterization and structure studies 总被引:1,自引:0,他引:1
Bisphosphoglycerate mutase (EC 5.4.2.4.) is an erythrocyte-specific enzyme whose main function is to synthesize 2,3-diphosphoglycerate (glycerate-2,3-P2) an effector of the delivery of O2 in the tissues. In addition to its main synthase activity the enzyme displays phosphatase and mutase activities both involving 2,3-diphosphoglycerate in their reaction. Using a prokaryotic expression system, we have developed a recombinant system producing human bisphosphoglycerate mutase in E coli. The expressed enzyme has been extracted and purified to homogeneity by 2 chromatographic steps. Purity of this enzyme was checked with sodium dodecyl sulfate polyacrylamide gel and Cellogel electrophoresis and structural studies. The bisphosphoglycerate mutase expressed in E coli was found to be very similar to that of human erythrocytes and showed identical trifunctionality, thermostability, immunological and kinetics' properties. However, the absence of a blocking agent on the N-terminus results in a slight difference of the electrophoretic mobility of the enzyme expressed in E coli compared to that of the erythrocyte. 相似文献