Search PubMed⌕ Search

Biomedical subjects

P Rubin

Publications and source records attributed to P Rubin.

At least 307 records · Page 17Linked to original sources
PubMed1980

A comparative study of automated blood pressure recorders.

Four automated blood pressure machines (Arteriosonde 1225, Bosomat 11D, Elag Koln BE 237R and Omron HEM 3) have been compared with each other and with the Hawksley Random Zero Sphygmomanometer in 18 subjects with a wide range of BP. Each form of measurement provided a high degree of internal consistency. The Arteriosonde 1225 consistently recorded systolic and diastolic pressures which were below the values obtained with the Random Zero instrument (P=0.001). The other 3 automated machines recorded BPs which did not differ significantly from the Random Zero or from each other. Heart rate readings did not differ significantly for any of the machines compared to manual recording. The disparity attributable to the Arterisonde could result from its being the only form of measurement to use an ultrasonic rather than a microphonic recording technique. However, the cheaper and more portable automated machines produce results which closely reflect those obtained by using a mercury sphygmomanometer.

Blood Pressure Determination↗
PubMed1980

Medulloblastomas.

"Analysis of 29 cases evaluated at SMG, Rochester, N.Y." This study analyzed 29 patients with the diagnosis of medulloblastoma evaluated at Strong Memorial Hospital, Rochester, New York. Twenty-three patients received combined (surgery and radiotherapy) treatment. Six had surgery alone. Chemotherapy was never employed as a primary treatment, however, two cases were treated with drugs at the time of relapse. The patients having craniospinal irradiation had a better survival rate when compared with the group receiving cranial irradiation or surgery alone. The five year survival rate for the first group was 50% versus 20% for the second group and 0% for the third group. The main cause of failure was recurrence in the posterior fossa. Fifteen patients failed in this area representing 88% of the total failures. Seeding to the spinal cord was determined in 5 patients, four of whom did not have spinal cord irradiation. One patient failed outside the field of treatment in the conus medullaris six months after radiation.

Adolescent↗
PubMed1979

Atenolol determination by high-performance liquid chromatography and fluorescence detection.

A high-performance liquid chromatographic procedure using a fluorescence detector for the analysis of atenolol in plasma and whole blood is described. It employs a simple and rapid method of preparation. Atenolol and metoprolol as the internal standard are chromatographed as ion pairs with heptanesulfonic acid. The method is sensitive and reproducible with accurate detection at concentrations as low as 2 ng/ml in whole blood and plasma, and a coefficient of variation of 4.7% over the range 2 ng/ml to 1000 ng/ml.

Atenolol↗
PubMed1979

Comparative study of automatic blood-gas analysers and their use in analysing arterial and capillary samples.

Three automatic blood-gas analysers were compared for ease of use; calibration; reproducibility and accuracy of results; maintenance; fault-finding; and use of expert technician time. Results obtained from arterial and capillary blood were compared with duplicate values obtained with a semi-automatic analyser controlled and calibrated with tonometered blood. No analyser was fully automatic, and all three needed maintenance by expert technicians. Difficulties were encountered when inexperienced operators used the machines. One automatic blood-gas analyser gave aberrant values for oxygen pressure (PO2) due to electrode dysfunction that was not indicated by the fault-finding system. A second analyser gave significantly lower values for blood pH than the standard machine. A comparison of pH, carbon dioxide pressure (PCO2), and PO2 measured in 40 simultaneous paired samples of arterial and arterialised capillary blood showed no significant difference for pH or PCO2, but the PO2 values were significantly lower in the capillary samples over the range studied. We conclude that all machines perform satisfactorily in terms of blood-gas analysis, but none may be regarded as fully automatic. Some degree of technical supervision is essential, as is proper training for all potential users.

Arteries↗
PubMed1979

Influence of congestive heart failure on prazosin kinetics.

The kinetics of oral prazosin was studied in 10 healthy normal subjects (NS) and in 9 patients with congestive heart failure (CHF). NS received a single 5-mg dose, and blood concentrations of prazosin (CB) were measured, using a specific HPLC assay, during an 8-hr period. CHF patients received a 2-mg dose after which CB was measured for 10 hr. These patients then received 2 to 5 mg prazosin every 8 hr for 48 hr. After the last dose of prazosin, CB was measured for 24 hr. After the initial dose, time to peak CB did not differ significantly between that of the NS (123 +/- 19 SEM min) and of patients with CHF (132 +/- 31.3 min). AUC/mg prazosin was greater (p less than 0.001) in patients with CHF (3,385 +/- 380 Ng x min/ml) than in NS (1,603 +/- 208 ng x min/ml). Elimination of prazosin from blood was slower in CHF patients (t1/2 = 374 +/- 33.4 min) than in NS (t1/2 = 144.5 +/- 4.3 min) (p less than 0.001). These data suggest that in patients with CHF the elimination of prazosin is substantially slower than in NS and therefore higher steady-state prazosin concentrations can be expected in CHF patients than in NS.

Administration, Oral↗
PubMed1979

Plasma catecholamines in man are not influenced by the inhibition of prostaglandin synthesis.

Indomethacin has been reported to potentiate the release of noradrenaline from sympathetic nerve endings in vitro and to increase urinary noradrenaline excretion in rats. We have studied the influence of indomethacin on plasma catecholamine levels in 10 normal men, using measurement of plasma renin activity (PRA) as an index of the pharmacodynamic effect of indomethacin. Both in the supine and standing positions indomethacin failed to alter the plasma concentrations of noradrenaline, adrenaline or dopamine, while PRA was markedly suppressed. It is concluded that in the intact human indomethacin does not influence catecholamine concentrations.

Adult↗
PubMed1978

The management of clinical stage I endometrial carcinoma.

A retrospective analyses of 307 cases with clinical Stage I endometrial carcinoma was done in an attempt to determine the role of radiation therapy in the optimal treatment of this disease. A review of the modern literature with over 9000 cases served as a useful tool to corroborate inferences and conclusions. The present series has 155 patients (51%) treated with preoperative megavoltage external pelvic radiation with a variation in doses of less than 6%. Five-year survival estimates (79%-83%) in clinical Stage I endometrial carcinoma are similar among the several main treatment combination that are employed; they become a useless parameter for any comparison. The pelvic failure rate constitutes a more useful guideline in assessing the most adequate therapy. The pathologic grade of the tumor is the main prognosticator in endometrial carcinoma. Intimately related to the tumor grade is the depth of myometrial invasion of the carcinoma. The size of the uterus and/or its cavity carry less prognostic significance than traditionally thought. For grade I lesions, there is little error in diagnosis, few pelvic failures and excellent survival (96%); they could be approached with initial surgery and postoperative radiation reserved for selected patients. For grade 2 tumors, the error in diagnosis and the failure rate increases with an overall survival of 87%. For grade 3 tumors, the error in diagnosis and failure rates are quite high with a 5 year survival of only 70%. Preoperative radiation, especially external beam therapy, is suggested for grades 2 and 3 Stage I tumors. The use of this treatment modality yields only 3% pelvic failure and an overall 5 year survival of almost 90%.

Carcinoma↗
PubMed1978

Thyroid abnormalities following neck irradiation for Hodgkin's disease.

Thyroid function and scans were evaluated in fifty disease-free patients 2 to 16 years after receiving neck irradiation for the treatment of Hodgkin's disease. Twenty-five of 50 patients had abnormal thyroid studies: eight were hypothyroid, two were hypothyroid and had abnormal scans, and fifteen had abnormal scans. Of the 15 patients with abnormal scans, one had an isolated elevation of TSH (thyroid stimulating hormone) and one developed exophthalmos. These data, obtained within a relatively short follow-up period, indicate that morphologic and functional abnormalities of the thyroid gland are not uncommon in patients who have received irradiation to the thyroid gland in the course of treatment for Hodgkin's disease. There is need for continuous reevaluation of the thyroid status in such patients.

Adolescent↗
PubMed1978

Fine structural studies of radiation-resistant human squamous cell carcinomas.

Squamous cell carcinomas of the oral cavity are relatively common lesions, and often can be controlled by radiation therapy. Recently, a series of these tumors has been encountered which did not respond positively to irradiation, necessitating subsequent extensive surgery. This report describes some fine structural changes which were observed in squamous cell carcinomas following exposure to x-irradiation. In addition to the common, keratin-forming differentiated cell, others which were observed were secretory-like, undifferentiated and phagocytic cells. Undifferentiated tumor cells occasionally became incorporated, at least temporarily, as a component of the blood vessel wall, perhaps reflecting metastatic potentiality. It is proposed that irradiation may either increase potential avenues of tumor cell differentiation or inactivate inhibitors thereof.

Aged↗
PubMed1978

The Radiation Therapy Oncology Group: a progress report.

The Radiation Therapy Oncology Group (RTOG), founded in 1971, comprises 35 university hospitals which are participating in 21 active protocols, four registries and eight pilot studies, including Phase I/II studies. Case accession has grown to over 1000 in 1977 with 19,801 patients being entered in the RTOG initial registration. Goals of the RTOG include: advancing knowledge of the role of radiation therapy in disease management; improving control of primary and regional disease; reducing morbidity and complications from treatment; and collaborating with other oncology disciplines to obtain data on multimodality therapy.

Clinical Trials as Topic↗
PubMed1977

Radiation toxicology: quantitative radiation pathology for predicting effects.

Radiation toxicology is the quantification of radiation pathophysiology. It is based upon the development of more precise and accurate radiation dose response data in humans. Such information is particularly important because of the development of combined radiation therapy and chemotherapy. The search for models which will predict radiation injury is presented along with innovative approaches to the 3-dimensional reconstruction of isodose curves in autopsy material, and ultrastructural studies.

Animals↗