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R Pike

Publications and source records attributed to R Pike.

12 recordsLinked to original sources
PubMed1992

Characterisation of the activity and stability of single-chain cathepsin L and of proteolytically active cathepsin L/cystatin complexes.

The activity of single-chain cathepsin L was found to be markedly dependent on cysteine concentration, while a covalent, proteolytically active cathepsin L/cystatin complex was less cysteine-dependent. Cysteine levels and ionic strength did not affect the stability of either enzyme form and both enzyme forms were found to be stable for significant periods of time at or near physiological pH.

Animals↗
PubMed1989

A high yield method for the isolation of sheep's liver cathepsin L.

A method, giving twice the yield of the previous method, for the isolation of sheep's liver cathepsin L is described. The method uses three phase partitioning (TPP) in t-butanol/water/ammonium sulphate mixtures, followed by two chromatographic steps, at different pH values, in a single column of S-Sepharose.

Animals↗
PubMed1984

The pictorial scale of perceived competence and social acceptance for young children.

A new pictorial scale of perceived competence and social acceptance for young children, a downward extension of the Perceived Competence Scale for Children, is described. There are 2 versions of this instrument, 1 for preschoolers and kindergartners and a second for first and second graders, each tapping 4 domains: cognitive competence, physical competence, peer acceptance, and maternal acceptance. Factor analyses reveal a 2-factor solution. The first factor, general competence, is defined by the cognitive and physical competence subscales. The second factor, social acceptance, comprises the peer and maternal acceptance subscales. The psychometric properties were found to be acceptable. Weak correlations between children's and teachers' judgments are discussed in terms of the young child's tendency to confuse the wish to be competent or accepted with reality. It is urged that this instrument not be viewed as a general self-concept scale but be treated as a measure of 2 separate constructs, perceived competence and social acceptance.

Child↗
PubMed1983

Further analysis of the Crist data on matching performance and the similarity structure of the stimulus set.

We argue that Crist's (1981) analysis of his data on letter matching is incomplete because he did not sufficiently distinguish overall context similarity from the similarity of the other letter present on a trial. That is, the separation of the effects of context similarity and visual similarity is required for a complete analysis. Accordingly, for different trials, modified indices of context similarity are derived and linear regression analyses made to determine the separate effects of context and visual similarity. The results of these analyses show that on different trials, visual similarity is much more predictive of latency than context similarity and that subjects must therefore be making visual similarity judgments, that considerably affect latency variation on these trials. Consequently, we argue that visual similarity judgment may be likewise affecting latency on same trials. However, some simple correlations indicate that context may be more predictive of latency on physically different same trials. We concluded that what can be said about context depends on the type of trial and that the comparative strength of name processing should also be assessed by the method described here.

Discrimination, Psychological↗
PubMed1979

Biosynthesis and characterisation of IgMlambda in a case of chronic lymphocytic leukaemia with intracellular immunoglobulin inclusions.

Lymphocytes from a patient with chronic lymphocytic leukaemia were found to contain crystalline inclusions in the cytoplasm. These crystals were characterised as IgMlambda immunoglobulin. The cells did not have detectable surface immunoglobulin. No paraprotein was detected in the serum and no excess of immunoglobulin was detected in the urine. The cells incorporated radioactive leucine into mu and lambda chains during an 18-hour culture. Studies of labelled lysate immunoglobulin revealed a molar excess of heavy chain over light chain while in contrast free light chain was the only detectable secreted immunoglobulin product during the culture period. These findings are discussed in relation to immunoglobulin synthesis by normal and other neoplastic lymphocyte preparations.

Aged↗