Search PubMed⌕ Search

Biomedical subjects

J Walker

Publications and source records attributed to J Walker.

At least 451 records · Page 25Linked to original sources
PubMed1980

[Experimental study of bacteriophage removal from the lagoon basin].

Polluted river water was studied in an experimental lagoon to determine efficiency of removal of bacteriophages injected at the inlet of the lagoon. The bacteriophages were not significantly affected by the purification process and were found to migrate to the outlet in 4 to 5 days. They were detected 143 days after injection although about 80% of the added virus was removed by the lagoon treatment. These results contrast with those obtained with Salmonella, 99.9% of which were removed.

Adsorption↗
PubMed1979

Radioimmunoassay of class-specific antibodies to Streptococcus mutans in monkey serum and saliva.

A radioimmunoassay (RIA) has been developed to measure class-specific antibodies to Steptococcus mutans in the serum and saliva of monkeys (Macaca fascicularis). Anti-human immunoglobulin antibodies purified by affinity chromatography on immobilised monkey immunoglobulins and labelled with 125I were employed. Formolised cells of S. mutans and an extract of culture supernatant adsorbed to polystyrene wells were used as solid-phase antigens. The coefficients of variation for IgG, IgA and IgM assays were less than or equal to 10% for both antigen systems. Two monkeys were immunised with formolised cells of S. mutans by subcutaneous injection and subsequent instillation of bacterial cells into their right parotid ducts. IgG, IgA and IgM antibody responses to S. mutans in samples of serum and saliva were quantitated by RIA. Immobilisation of purified components of S. mutans on polystyrene wells enabled the measurement of antibody response to a number of antigens to be made. The RIA is a sensitive, reproducible and quantitative method of measuring serum and salivary antibody responses in monkeys.

Adsorption↗
PubMed1979

Caloric requirements for weight gain in anorexia nervosa.

The caloric requirements for weight gain were studied in 29 patients during 35 days of treatment for anorexia nervosa. Associations between the caloric requirements for weight gain and the amount of body weight depletion at the beginning of treatment were analyzed. There was a positive correlation between the percentage standard weight on the 1st day of treatment and the excess calories required to gain a kilogram. This highly significant correlation was possibly due to differences in type to tissue formed and/or an increase in metabolic rate as part of an adaptive response, as the patient nears target weight.

Adolescent↗
PubMed1979

Characterization of pyrimidine deoxyribonucleoside kinase (thymidine kinase) and thymidylate kinase as a multifunctional enzyme in cells transformed by herpes simplex virus type 1 and in cells infected with mutant strains of herpes simplex virus.

Pyrimidine deoxyribonucleoside kinase (thymidine kinase [TK]) was purified from two herpes simplex virus type 1 (HVS-1)-transformed TK-deficient mouse (LMTK-) cell lines and from LMTK- cells infected with HSV-1 mutant viruses coding for variant TK enzymes. These preparations exhibited normal or variant virus-induced thymidylate kinase activities correlating with their relative TK activities. Neither virus-induced activity was detected in LMTK- cells infected with an HSV-1 TK-deficient mutant. These results suggest that HSV-1 thymidylate kinase activity and TK activity are mediated by the same protein.

Animals↗
PubMed1979

The distinction between the affective psychoses and schizophrenia.

In an attempt to demonstrate a valid boundary between schizophrenia and the affective psychoses, discriminant function analyses have been carried out with history, mental state and follow-up data in two populations of patients. A bimodal distribution of discriminant scores was obtained in one of them (a general psychotic sample of 128 patients), using a discriminant function derived from the same sample; but when the function was applied to the second population (a schizoaffective sample of 106 patients) the distribution was ambiguous. Functions derived from the schizoaffective sample produced highly skewed distributions of discriminant scores in the general psychotic sample. Kraepelin's hypothesis that the functional psychoses consist of two distinct disease entities receives some support from our findings, but there is still no compelling evidence that the universe of psychotic patients falls naturally into these two groups.

Bipolar Disorder↗
PubMed1978

Antibodies to donor B lymphocytes and mixed lymphocyte culture blocking in cadaveric renal transplantation.

In 33 renal allograft recipient-donor pairs, B and T lymphocyte complement-dependent cytotoxicity crossmatches and mixed lymphocyte culture (MLC) blocking experiments were performed and the results were correlated with graft outcome. MLC blocking particularly in the unidirectional culture against donor-stimulating cells, was highly correlated with the presence of complement-dependent cytotoxicity antibodies against donor B lymphocytes. Grafts in both MLC blocking and B lymphocyte crossmatch-positive groups fared equally as well as those without positive tests. No difference in graft outcome was noted when the presence or absence of MLC blocking was examined in relationship to positive or negative B lymphocyte complement-dependent cytotoxicity crossmatching.

B-Lymphocytes↗
PubMed1978

Multiple-scored tablets. Weight and content uniformity of subdivisions and distribution of active constituent within and between tablets.

Using three brands of multiple-scored levodopa tablets, B.P. (500 mg) and one brand of sulphamethoxypyridazine tablets B.P. (500 mg) the weight and content uniformity of the subdivisions has been examined. It is shown that quartering of such tablets can result in subunits which do not conform to recognized standards of weight uniformity, and in some instances content uniformity may be questionable. The homogeneity of distribution of active constituent between tablets has been determined and compared with that within tablets (between quarters of individual tablets). Statistical evaluation of the results is presented.

Drug Compounding↗
PubMed1978

Donor-specific preformed B-lymphocyte antibodies and mixed lymphocyte culture (MLC) blocking in cadaver renal allograft recipients.

B- and T-lymphocyte CDC crossmatches and MLC blocking experiments were performed for 33 cadaver renal allograft donor-recipient pairs. Unidirectional MLC blocking was highly correlated with a positive B-cell crossmatch. Grafts in both the MLC blocking and B-cell crossmatch positive groups fared equally as well as those without positive tests. No difference in graft outcome was noted when the presence or absence of MLC blocking was examined in relationship to B-cell crossmatch results.

B-Lymphocytes↗