Free-Operant Acquisition with Delayed Reinforcement
The acquisition of free-operant lever pressing by hungry rats was investigated under a schedule in which the first lever press in each second programmed a reinforcer delivery after a fixed delay. In… Expand
The Effect of Age on the Creatine in Red Cells
The creatine in packed red cells was estimated by the diacetyl‐i‐naphthol technique. The error due to the presence of other guanidino compounds in the cells was found to be small.
Alcohol and sleep in young adults
- O. H. Rundell, B. Lester, W. J. Griffiths, H. L. Williams
- Psychology, Medicine
In two separate experiments, sleep patterns of 17 young male adults were examined following single and repeated doses (0.9 g/kg body weight) of alcohol. A third study of 10 additional Ss measured the… Expand
Tryptophan and sleep in young adults.
- W. J. Griffiths, B. Lester, J. D. Coulter, H. Williams
- Psychology, Medicine
- 1 May 1972
Oral administration of L-tryptophan increases brain serotonin levels by following normal 5-hydroxyindole pathways (Moir & Eccleston, 1968). Since recent studies (Jouvet, 1969) suggest that serotonin… Expand
The effect of different environments during infancy on adult behavior in the rat.
Sleep patterns in growth hormone deficient children and age-matched controls: developmental considerations.
- W. Orr, G. Vogel, M. Stahl, W. J. Griffiths, J. R. Seely
- Biology, Medicine
- 1 July 1977
Ten patients with isolated growth hormone (GH) deficiency and 13 age-matched normal controls were studied. All patients were below the 3rd percentile in height and weight. All but 1 subject were… Expand
The factors influencing the concentration of hydrochloric acid during gastric digestion
Rapid Colorimetric Micro-method for Estimating Glucose in Blood and C.S.F. Using Glucose Oxidase
Case 2. Epistaxis as a Presenting Symptom.-A 5-yearold Chinese boy was admitted on May 15 with the complaint of fever for four days, bleeding from the nose the night before admission, and vomiting of… Expand
Estimation of creatine in red cells.
- W. J. Griffiths
- Chemistry, Medicine
- Journal of clinical pathology
- 1 May 1968
Because there is a considerable decline in the creatine of the human red cells with increasing age, the creatine in a mixed population of cells is a sensitive index of their mean age and therefore of… Expand
The Estimation of Noradrenaline in Urine and Its Excretion in Normal and Hypertensive Subjects
Recognition of the association of paroxysmal a hypertension with phaeochromocytomata, actively I secreting tumours of the chromaffin tissue of the i adrenal medulla, has resulted in the need for more… Expand