Search PubMed⌕ Search

Biomedical subjects

L Parker

Publications and source records attributed to L Parker.

At least 235 records · Page 13Linked to original sources
PubMed1979

Menstrual cycle affects kinesthetic aftereffect, an index of personality and perceptual style.

Research suggests that kinesthetic aftereffect (KAE) scores reflect status on a postulated stimulus intensity modulation (SIM) mechanism that damps down subjective stimulus intensity for some (reducing) and increases it for others (augmenting). Such a mechanism would help account for empirically observed individual differences in such behaviors as pain tolerance, sensory deprivation reactivity, and stimulation seeking. It was hypothesized and confirmed in three adult female samples that KAE varies curvilinearly over the menstrual cycle: Greater KAE reduction occurs at the cycle's beginning and end. Neither tiredness, oral contraception, medication, attention, nor social expectations can explain this finding. Of the behaviors studied in the KAE literature, only five are also encompassed by the menstrual cycle literature. Four of these (antisocial behavior, acute schizophrenic episodes, accidents, and activity level) show similar curvilinearity over the cycle. We hypothesize that cyclical variation in the SIM mechanism mediates the curvilinear pattern observed for both these four behaviors and KAE.

Adult↗
PubMed1979

Lack of adrenal androgen stimulation by ACTH in extreme hyperprolactinemia.

Acute and prolonged alpha 1-24 corticotropin stimulation was performed on a treated chromophobe adenoma patient with partial ACTH deficiency and extreme hyperprolactinemia. Cortisol and aldosterone stimulated normally. However, the basal concentrations of androstenedione (A) and dehydroepiandrosterone (DHA) were low, and that of DHA-sulfate (DHAS) was undetectable. Furthermore, A and DHA did not stimulate normally, and DHAS did not stimulate at all. It has been claimed that adrenal androgen production is increased in hyperprolactinemia. However, the inability of prolactin (Prl) to maintain adrenal androgen (AA) secretion, with and without added ACTH, is demonstrated in this patient.

Adenoma, Chromophobe↗
PubMed1979

Clinical results of autotransplantation after nitrosourea therapy.

Bone marrow harvested from two previously treated patients was cryopreserved prior to their first dose of Methyl CCNU. The thawed bone marrow was reinfused 96 hours after a subsequent dose of MeCCNU in one patient after the previous dose caused severe myelosuppression. In the other patient, the bone marrow was given 96 hours after an escalation of the MeCCNU dose. In both patients, myelosuppression was abrogated and viable stem cells were recovered in the peripheral blood.

Adenocarcinoma↗
PubMed1979

Saccades in extremes of lateral gaze.

Saccades (between targets at 30 degrees and 40 degrees) were recorded with DC electro-oculography in 10 normal subjects. Velocity-amplitude relationships were examined on the basis of abduction vs. adduction and centering vs. eccentric movement. In these small peripheral saccades the former pairing showed no consistent differences in peak velocity, whereas centering saccades were consistently faster than both eccentric movements and those made around primary position.

Adult↗
PubMed1978

The nutritional and metabolic effects of a carbohydrate-rich diet in a glycogen supercompensation training regimen.

It has been suggested that glycogen depletion followed by a protein-fat diet and a carbohydrate-rich diet improves performance. This study was designed to determine the nutritional and metabolic effects of a carbohydrate-rich diet in a glycogen supercompensation training regimen. Four male subjects participated in a 5-week protocol of which the first 3 weeks were devoted to a control period and the last 2 weeks to the experimental phase of the study. The variables measured before, during, and following the experimental phase included anthropometric and basal metabolic rate measurements, urinary and serum analysis for vitamins, SMA 12/60 blood profile and aerobic performance (VO2max). Results indicated an appreciable modification of the metabolic and nutritional profile of the subjects as a result of the diets. During the protein-fat diet there was a decrease in serum glucose and resting respiratory quotient and an increase in cholesterol, blood urea nitrogen, riboflavin, and N1-methylnicotinamide excretion. Subsequent to the carbohydrate-rich diet there was an increase in triglycerides and vitamin C, riboflavin, and thiamin excretion while there was a decrease in serum blood urea nitrogen, and N1-methylnicotinamide excretion. Aerobic performance was slightly decreased and the mean postexercise lactate levels were slightly higher after the carbohydrate-rich diet. It was hypothesized that the reduced niacin intake during the carohydrate-rich diet may hamper the aerobic oxidative pathways.

Adult↗
PubMed1978

End-point nystagmus.

Infrared oculography was performed during sustained lateral gaze in 12 normal subjects to investigate end-point nystagmus while fixating a target light. Five failed to develop nystagmus despite deviation up to 40 degrees from 4 to 5 min. Six subjects developed nystagmus immediately or shortly after reaching the deviated position. In one, the nystagmus (0.5 degrees to 1 degree and 1.0 Hz) began with only a 20 degree deviation. In another subject, "fatigue" nystagmus developed after 1 min at 30 degrees, and at 35 degrees nystagmus began within 2 sec. One subject developed only fatigue nystagmus, which began after more than 4 min of sustained deviation. In all instances the slow phase had primarily a linear, rather than exponential, waveform.

Adult↗