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Biomedical subjects

C H Brown

Publications and source records attributed to C H Brown.

At least 109 records · Page 6Linked to original sources
PubMed1982

Vertical and horizontal sound localization in primates.

Minimum audible angles for localization in the vertical and horizontal planes were psychophysically determined in Old World monkeys (Macaca). In the vertical condition the test stimuli consisted of primate vocalizations and bands of noise. Minimum audible angles ranged from 3 degrees to greater than 20 degrees for signals of various bandwidths. The acuity of vertical localization was dependent upon the high-frequency content of the signal. Two of the three monkeys were unable to vertically localize sounds if the high-frequency limit of the signal was below 2000 Hz. The acuity of horizontal localization was tested for pure tones 500, 2000, and 8000 Hz in frequency, positioned at several referent locations in the right frontal quadrant. The acuity of horizontal localization decreased as the test azimuth was displaced from the midline. Minimum audible angles ranged from approximately 4 degrees to greater than 20 degrees and varied as a function of test azimuth.

Animals↗
PubMed1982

Cancer in families of former medical students followed to midlife: prevalence in relatives of subjects with and without major cancer.

In an ongoing longitudinal study of former medical students, now physicians in midlife, the prevalence of cancer among relatives of 46 probands affected by cancer has been compared with that of two control groups of cancer-free probands. Overall, the prevalence of cancer among relatives of the three groups of probands was similar. However, male probands with cancer appeared to have a greater prevalence of cancer among their relatives than did male cancer-free probands, while the corresponding comparisons for the smaller groups of female probands showed the opposite tendency. Among the relatives of cancer probands of either sex, there was evidence of familial clustering of cancer. Where two relatives in a proband's family had the same type of cancer, the two relatives were usually on the same side (paternal or maternal) of the family. Ages at onset of cancer and types of cancer in relatives of the cancer and cancer-free probands did not reveal any significant differences.

Adult↗
PubMed1981

Biochemical abnormalities of platelets in renal failure. Evidence for decreased platelet serotonin, adenosine diphosphate and Mg-dependent adenosine triphosphatase.

The platelet content of adenosine triphosphate (ATP), adenosine diphosphate (ADP), serotonin and ouabain-insensitive, magnesium-dependent adenosine triphosphatase (ATPase) was determined in patients with chronic renal failure, patients on chronic hemodialysis, and kidney transplant recipients. Platelet ATP content was normal in all. By contrast, ADP content, expressed in mumol/10(11) platelets, was significantly lower in renal failure: 1.82 +/- 0.96 compared to 2.51 +/- 0.97 in normals (p less than 0.05), but not in dialyzed or transplanted patients; 2.27 +/- 0.96 and 1.87 +/- 0.87, respectively. The mean content of serotonin was also significantly lower in renal failure patients: 0.52 microgram/10(9) platelets as compared to 0.90 microgram/10(9) platelets in normals (p less than 0.05) but was not significantly different in dialyzed and transplanted patients. ATPase was significantly lower in renal failure: 3.13 +/- 1.2 mumol Pi/10(9) platelets in whole suspension and 0.71 +/- 0.22 Pi/mg protein/h in membrane preparation compared to 4.74 +/- 1.1 and 1.18 +/- 0.19, respectively, in normals, and was significantly lower in dialyzed and transplanted patients. Experimental azotemia (BUN 65-86 mg/100 ml), induced by the oral ingestion of urea 2-3 g/kg body weight over 24 h, failed to induce any of these abnormalities. The abnormality in platelet ADP and serotonin content in renal failure paralleled the functional platelet defects which characterize these patients and were reversible following dialysis and transplantation.

Adenosine Diphosphate↗
PubMed1981

Automatic stop-order policy for PRN medications in skilled nursing facilities.

From the data collected during this 4-month investigation of 37 skilled nursing facility (SNF) patients, one may conclude that using automatic stop-order policies for PRN medications is effective in controlling and eliminating unnecessary medications that are not being used by nursing home patients. PRN medications were reduced significantly from 4.1 to 2.1 per patient (p less than 0.01). Also, a significant amount of savings to these patients or their third-party payers, potentially $1500 per year in this SNF, resulted from the credit issued for discontinued unit-of-use medications. The reported potential cost savings could not have been obtained from medication being dispensed in traditional prescription packaging. Therefore, this study's data should influence state and governmental agencies to begin considering reimbursing vendor pharmacies for implementing unit-of-use packaging in their nursing homes. The data illustrate and support another method in which pharmacy consultants can prove cost-effectiveness when they are used properly in SNFs.

Aged↗
PubMed1981

Compliance with federal regulations for pharmaceutical services in skilled nursing facilities.

The extent of consultant pharmacist compliance with federal regulations for pharmaceutical services in skilled nursing facilities is reported. Twenty geriatric nursing facilities in Indiana were surveyed over a five-month period. The performance of consultant pharmacists was rated with regard to their facility and patient monitoring functions and their administrative (policy development) activities. Their facility monitoring functions and their patient monitoring functions consisted of both clinical and supervisory responsibilities. Performance was rated on a 4-point scale with a ranking of less than 75% considered unsatisfactory. Eighty percent of the pharmacists were performing their facility monitoring clinical activities at or above an 80% performance level. Ninety-five percent of the pharmacists were performing their facility monitoring supervisory functions at or above an 80% performance level. The supervisory components of patient monitoring were being performed at a mean level of 89%, in contrast to a level of 62% found for the clinical components of patient monitoring. The patient monitoring functions were being performed below the satisfactory level of 75% of the consultant pharmacists. The younger pharmacist (ages 25-28) were performing the patient monitoring clinical functions at a significantly higher level (p less than 0.01) that the pharmacists in the older age group. Seventy percent of the pharmacists were performing their administrative functions at a satisfactory level.

Consultants↗
PubMed1980

Localization of noise bands by Old World monkeys.

The acuity of auditory localization in Old World monkeys (Macaca) was determined psychophysically for 44 noise bands graded in bandwidth and center frequency. The acuity of localization was assessed through the method of constant stimuli under free-field conditions in an anechoic chamber. Monkeys were trained through positive-reinforcement operant-conditioning procedures to report a change in azimuth of the signal by releasing a response disk. The results show that localization thresholds are dependent upon the bandwidth of the signal over much of the macaque's range of audibility. Thresholds for the detection of a change in location varied from 18 degrees (for a signal 250 Hz in bandwidth centered at 11 200 Hz) to 4 degrees (for a signal 8000 Hz in bandwidth centered at 8000 Hz). The results suggest that the localization of spectrally complex signals is determined by a mechanism sensitive to periodicity (time-domain) information across the monkey's range of audibility.

Animals↗
PubMed1980

Use of PRN medications in skilled nursing facilities.

Many elderly individuals in skilled nursing facilities (SNFs), afflicted with an array of acute and chronic diseases, may have as many as 20 different prescribed medications administered on a pro re nata (PRN) basis. In this study, 20 SNFs in Indiana were inspected. Data on PRN medications were taken from medical charts to determine the extent of PRN medication use by the patients. From one to 10 PRN medication were prescribed per patient; 47% of the patients had not used any of their PRN medications. Further data are needed to justify PRN medication prescribing and usage and to decrease the potential for hidden medical costs, adverse drug effects, and drug interactions.

Drug Prescriptions↗
PubMed1979

Characteristics of national and world class female pentathletes.

Nine national and world-class female pentathletes were assessed for body composition, maximal aerobic power (Vo2max), strength, and speed. The subjects averaged 175.4 cm in height, 65.4 kg in weight, 11.0% relative body fat, 45.9 ml kg min-1 in Vo2max, and 8.35 m/sec for maximal running speed. When compared with other athletic females, this group was tall and lean with good, but not exceptional, maximal aerobic power. Group means for one-repetition maximum lifts were 59.7 kg (power clean), 61.5 kg (horizontal bench press), 60.0 kg (pull down), 87.9 kg (squat), 44.9 kg (include bench press), and 36.3 kg (leg curl). Within this elite group the most successful performers were stronger and possessed a greater lean body weight which together suggest the importance of muscle mass for success in the pentathlon.

Adult↗
PubMed1978

Localization of primate calls by old world monkeys.

Monkeys (Macaca) were trained by operant conditioning techniques to report the minimum detectable change in location of a sound in space, and were tested with a series of recorded coo or clear call vocalizations. Acuity of localization varied from approximately 4 degrees to 15 degrees and was a function of the magnitude of the change in pitch (frequency modulation) of the different clear calls.

Animals↗
PubMed1976

Influence of cephalosporin antibiotics on blood coagulation and platelet function.

Administration of cephalothin to normal volunteers in maximal doses of 300 mg/kg per day resulted in a combined defect of platelet function and blood coagulation. No such abnormalities were evident after infusion of cefazolin or cephapirin at a maximal dosage of 200 mg/kg per day. The observed thrombocytopathy was similar to but less severe than that induced by carbenicillin or ticarcillin and was not reflected by a prolonged bleeding time test or impaired prothrombin consumption. Moreover, it was not a consistent finding in those persons receiving cephalothin. A separate defect involving blood coagulation appeared to result from delayed fibrinogen-fibrin polymerization and was evidenced by extended values of the activated partial thromboplastin and thrombin time tests. It remains uncertain whether the abnormalities described may constitute clinically important hemostatic disorders in patients with normal renal function receiving large doses of cephalosporin antibiotics.

Blood Coagulation↗
PubMed1976

Pseudoobstruction in ceroidosis.

Diffuse deposition of ceroid pigment in the muscularis propria of the gastrointestinal tract in a patient with a long history of malabsorption of unknown origin is reported. The depostion of this waste pigment is not reversible and is related to prolonged depletion of vitamin E. Progressive dilatation and hypomotility of the entire gastrointestinal tract are demonstrated by radiographic studies and possibly related to infiltrate of ceroid pigment in the smooth muscle cell with resulting functional impairment. In the differential diagnosis of ceroidosis with other disease, scleroderma has the closest roentgenographic similarity. Pseudoobstruction of the small bowel which can develop must be treated conservatively to avoid unnecessary bowel resection.

Adult↗
PubMed1976

The effect of a low energy diet on the concentration of DDT in the adipose tissue of turkeys.

Turkey hens which had completed a breeding season and contained DDT in their fat were divided into 2 groups of 20 hens each. One group was fed a high wheat control diet throughout a 6 week period while another group was fed a low energy diet for 3 weeks and then the control diet for 3 weeks. Biopsy samples of adipose tissue taken initially and at 3 weeks and carcass adipose tissue samples of 6 weeks were analyzed for DDT and DDE. Total DDT concentration in adipose tissue increased when the hens were fed the low energy diet but decreased again when fed the control diet so that the overall change in DDT concentration over the 6 week period was not different for the two groups. The biopsy technique used in this study was successful in greatly reducing variability and improving precision.

Adipose Tissue↗