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41.
Dinesh S. Bhoj 《Biometrical journal. Biometrische Zeitschrift》1989,31(3):279-288
Two statistics are proposed for testing the hypothesis of equality of the means of a bivariate normal distribution with unknown common variance and correlation coefficient when observations are missing on both variates. One of the statistics reduces to the one proposed by Bhoj (1978, 1984) when the unpaired observations on the variates are equal. The distributions of the statistics are approximated by well known distributions under the null hypothesis. The empirical powers of the tests are computed and compared with those of some known statistics. The comparison supports the use of one of the statistics proposed in this paper. 相似文献
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46.
Dipak Kumar Banerjee 《Journal of biosciences》1987,11(1-4):311-319
Radio-labelled amphomycin (3H-amphomycin) forms a complex with dolichylmonophosphate in presence of Ca2+. Complex formation has also been documented with retinylmonophosphate and perhydromonoeneretinylmonophosphate. Analysis of
the space-filling model suggested both fatty acylated aspartic acid residue at the N-terminus of the lipopeptide and phosphate
head group of dolichylmonophosphate are necessary for the complex formation. The binding ability of amphomycin is then utilized
to localize dolichylmonophosphate in the microsomal membrane. Studies with microsomal membranes from hen oviduct suggested
that dolichylmonophosphate is located in the cytoplasmic side of the membrane. 相似文献
47.
S. K. Podder A. Chakraborti K. Vijayalakshmi P. Lalit Kumar Singh 《Journal of biosciences》1987,11(1-4):495-502
To examine how surface Potential controls the reactivity of glycoconjugates at cell surface, the interaction of galactose-sPecific
lectinse.g. peanut agglutinin,Ricinus cummunis agglutinin with liPosomes bearing asialo GM1 were studied in the Presence of varying amount of ganglioside mixture, GMn. The Presence of 5% GMn causes comPlete slowing down of PreciPitin reaction and thereby make carbohydrate moiety of asialo GM1 comPletely inaccessiblei.e. ‘cryPtic’. In contrast the Presence of 1–2% GMn enhances the aPParent rate and amPlitude of the PreciPitin reaction as surface Potential becomes more negative. The relevance
of the findings has been discussed in relation to the exPression and involvement of the cell-surface sialic acid residues
during develoPment and differentiation. 相似文献
48.
Three compounds capsaicin, curcumin and ferulic acid showing hypolipidemic activity have been tested in adult Wistar rats
fed high fat diets. Capsaicin (0.20 mg%) fed to female rats along with a 30% saturated fat diet lowered the rate of weight
gain, liver and serum triglycerides. In male rats it lowered only the liver and serum total and very low density and low density
lipoprotein triglycerides whether fed continuously for 13 or 8 weeks after interchanging the control and test diets from the
5th week onwards. Capsaicin fed to female rats in 30% mixed fat diet increased the rate of weight gain, lowered liver and
serum triglycerides, lowered adipose tissue lipoprotein lipase, elevated the hormone sensitive lipase and serum free fatty
acids. Capsaicin in 30% saturated fat diet lowered both the enzyme activities to a much lesser extent. Curcumin and ferulic
acid (both at 25 mg%) in 30% saturated fat diet tended to lower the rate of weight gain, liver total lipids and serum triglycerides.
It is of significance that a common dietary compound ‘capsaicin’ in the range of human intake triggers lipid lowering action
in rats fed high fat diets.
This paper was presented at the 55th Annual Meeting of the Society of Biological Chemists (India) held at Trivandrum during
December 15–17th, 1986. 相似文献
49.
The phylogenetic relationships among three derivative forms of the immigrans-Hirtodrosophila radiation viz. Chaetodrosophilella, Zaprionus and the immigrans species group are examined, by comparing the banding patterns of their polytene chromosomes and by analysing the nature of their heterochromatin. Based on the results of these studies it is concluded that D. quadrilineata has a very strong affinity with the members of the immigrans species group, while the genus Zaprionus represents a very distinct evolutionary lineage. This study further indicates that D. quadrilineata is a karyotypically primitive species having five pairs of rods and one pair of dots, while the karyotype of other members of the immigrans species group appears to have undergone modifications through fusions, fissions, inversions and the addition or deletion of heterochromatin to dots and other chromosomes. 相似文献
50.
Lack of dendritic Thy-1+ epidermal cells in mice with severe combined immunodeficiency disease 总被引:1,自引:0,他引:1
J L Nixon-Fulton P L Witte R E Tigelaar P R Bergstresser V Kumar 《Journal of immunology (Baltimore, Md. : 1950)》1987,138(9):2902-2905
C.B-17 scid (severe combined immunodeficiency disease) mice were used to evaluate the relationship of dendritic Thy-1+ epidermal cells (EC) to T lymphocytes (deficient in scid) and to NK cells (replete in scid). Epidermis from scid mice was deficient in dendritic Thy-1+ cells as determined by immunofluorescent staining of epidermal whole mounts. Similarly, epidermal cell suspensions from scid mice failed to proliferate in response to Con A, as compared with epidermal cell suspensions from C.B-17 control mice. Transplantation of normal bone marrow into scid mice reconstituted morphologically identifiable dendritic Thy-1+ EC in whole mounts, as well as Con A responsiveness of EC suspensions, thus indicating that the deficiency in dendritic Thy-1+ EC in scid mice is at the precursor level. These studies demonstrate that Thy-1+ EC are more closely related to T lymphocytes than to NK cells. 相似文献