Search PubMed⌕ Search

Biomedical subjects

R Thomas

Publications and source records attributed to R Thomas.

785 records · Page 44Linked to original sources
PubMedDate not supplied

[Ketoacidosis with false hyponatremia and important hyperchylomicronemia (author's transl)].

The ketoacidosis coma is described with plasma lipids at 270 g/l and hyperchylomicronemia. That is completed by a xanthomatosis rash and false hyponatremia (91 mEq/L). This fact is important because the prognosis is better than hyponatremia of ketoacidosis, after treatment evolution is good. Nevertheless because of the non-cooperation of the patient, sucrose level and HBA are high, and triglycerides are still elevated, but of type IV henceforth.

Adolescent↗
PubMedDate not supplied

The importance of appropriate concentrations of inspired carbon dioxide on induced hypothermia under halothane-ether azeotrope anesthesia.

Thirty adult mongrel dogs were divided into 3 equal groups and studied to define the optimal PCO2 level with azeotrope (halothane-diethyl ether) anesthesia under surface hypothermia (Groups I, II and III = F1CO2 0%, 5% and 10%, respectively). All animals were cooled to 18-20 degrees C and were subjected to 30 (Group I) or 60 minutes (Groups II and III) of total circulatory arrest. Group I animals had frequent arrhythmic episodes during cooling and postoperative motor disturbances occurred in 80% despite only 30 minutes of circulatory arrest. By contrast Group II animals were less arrhythmic during cooling; were easily resuscitated following 60 minutes of arrest and only 30% developed moderate reversible motor disturbances postoperatively. Hemodynamics were similar between Groups II and III during cooling but resuscitation using an F1CO2 of 10% (Group III) was extremely difficult and required massive cardiotonic support throughout rewarming. Furthermore, two dogs in Group III died within the first two postoperative days. However, none of the 8 survivors displayed neurological abnormalities. On balance, a ventilatory regimen utilizing 5% CO2 during surface-induced hypothermia under azeotrope anesthesia resulted in optimum intraoperative management and a satisfactory postoperative course and although some CNS disturbance (high-stepping gait) was noted, all animals recovered completely.

Acid-Base Equilibrium↗
PubMedDate not supplied

Experimental application of a multistep kinetic model for natural cytotoxicity: determination of rate constants for lytic programming and killer-cell-independent lysis.

A multistep kinetic model for natural cytotoxicity reactions in vitro is described that includes consideration of the effect of nonlytic target-binding lymphocytes on the experimentally determined kinetic parameters. The expression for the maximal velocity, Vmax, obtained using this model is essentially identical to that obtained using simpler models, whereas the expression for the apparent Michaelis constant, KappM, is considerably more complex. As a first step in the application of this model, experiments were designed to determine the relative contribution of some of the component terms to the value of KappM. Methods were developed that allow for experimental determination of the rate constants for both lytic programming and killer-cell-independent lysis (KCIL) steps in the cytolytic process. The results obtained support lytic programming as the rate-determining step in natural cytotoxicity reactions and demonstrate that terms related to nonlytic target-binding lymphocytes contribute significantly to experimentally determined values for KappM. In addition, the methods developed for the determination of the rates of lytic programming and KCIL should prove useful for various studies of the mechanism of cytotoxicity and the effects of drugs and disease on such phenomena.

Adult↗
PubMedDate not supplied

Prolongation of the safe interval of hypothermic circulatory arrest: 90 minutes.

Twenty-nine adult mongrel dogs were subjected to profound hypothermia and 90 minutes of total circulatory arrest. Pure surface (Group I) hypothermia and combined surface/perfusion techniques with bubble (Group II) and membrane (Group III) oxygenator systems were employed. Circulation was arrested at average esophageal temperatures of 18.4 degrees, 11.9 degrees and 8.5 degrees C in Groups I, II and III, respectively. Three animals in Group I failed to resuscitate. All survivors in the pure surface series developed postoperative gait (hypermetria) disturbances. One intraoperative death occurred in Group II and four of eight dogs arrested at esophageal temperatures above 10 degrees C but less than 15 degrees C developed motor disturbances during a three week neurologic evaluation period. Animals arrested below 10 degrees C (esophageal) did not display postoperative neurological abnormalities. Three dogs in Group III died from a hemorrhagic diathesis of uncertain etiology. None of the survivors (5) that were cooled and arrested below esophageal temperatures of 10 degrees C developed motor or sensory disturbances. We conclude that in the canine model the central nervous system can be protected for 90 minutes of total circulatory arrest at esophageal temperatures less than 10 degrees C.

Animals↗
PubMedDate not supplied

Intraosseous infusion.

Intraosseous infusion is recommended for children aged 6 years or less who have life-threatening conditions and require vascular access which cannot be achieved in a timely manner via another route. It is a reliable, safe procedure with a complication rate of less than 1%.

Age Factors↗
PubMedDate not supplied

The incidence of cataract in India is an overestimate.

BACKGROUND: Data obtained from surveys using distant direct ophthalmoscopy (DDO) with an undilated pupil for the detection of cataracts suggest an annual incidence of 3.8 million cataracts and over 9 million cataract-blind people in India today. METHOD: We recalculated the projections after adjusting for the sensitivity and specificity of DDO. RESULTS: Our calculations suggest that the incidence of cataract may have been overestimated by approximately 60%; corroborative evidence is provided. CONCLUSIONS: The specificity and sensitivity of diagnostic tests used in surveys may distort the projected figures and have adverse implications for the planning of services.

Cataract↗