Biomedical subjects

D Parra

Publications and source records attributed to D Parra.

22 records · Page 2Linked to original sources

PubMed1983

Gastro-intestinal parasites in calves in Colombia.

This study was conducted at Carimagua Research Centre in a high savanna area in the eastern plains of Colombia. The objectives were to identify the pathogenic parasites prevalent in the area and to study their seasonal variations and ecological conditions for use in planning control measures. The calves from two groups of 50 cows each (zebu crossbred) were used. Group I calves were born at the beginning of the rainy season and Group II calves later in the same period. The highest faecal egg counts observed were of trichostrongylid eggs. In necropsied animals Cooperia had high populations followed by Haemonchus. Throughout the rainy season there were favourable conditions for development and transmission of calf nematodes; animals born towards the end of the rainy season developed a lower infestation level which is probably easier to control. The animals were particularly susceptible to infestation with gastro-intestinal parasites at weaning. From these observations and in view of the relatively low stocking rate and the sequential burning of the savanna it is suggested that deworming be done at eight and 18 months of age.

Animals↗

PubMed1976

Venezuelan equine encephalitis virus: comparison of infectivity and virulence of strains V-38 and P676 in donkeys.

Two strains of Venezuelan equine encephalitis (VEE) virus were examined for the ability to replicate in, as well as to produce death among donkeys. One, a low passage strain known as strain P676 was originally isolated from mosquitos in Venezuela. The other, strain V-38 was isolated from a horse brain in 1938 and had undergone an unknown number of laboratory passages; it is used extensively for the preparation of inactivated VEE vaccine. Both strains were found to be approximately equal in their ability to infect donkeys. However, a quantity as small as 50% hamster intraperitoneal infectious units of strain V-38 resulted in fatal infection. On the other hand, as much as 631 million infectious units of strain P676 were nonfatal in one of two donkeys. It appears that strain V-38 is approximately 100 million times more virulent than strain P676 in equine species. One donkey which received strain P676 demonstrated a biphasic pattern of clinical illness and viremia, and there is suggestive evidence that another animal experienced a second and fatal clinical response 3 weeks after virus inoculation.

Animals↗

PubMedDate not supplied

[Applications of stable isotopes in biomedical sciences].

The employment of stable isotopes technology allows to perform a wide range of studies in vivo avoiding the utilisation of radioactive isotopes. As stable isotopes naturally occur in nature, the technique detects the enrichment in breath air of the tracer administered. Stable isotopes technology is increasingly being used in biomedical investigation due to the security of its use and the development and availability of new substrates. Breath tests such 13C-urea in the detection of Helicobacter pylori and 13C-octanoic acid for gastric emptying are the most important clinical applications.

Amino Acids↗

PubMedDate not supplied

Clinical and pharmacologic management of chronic heart failure associated with left ventricular systolic dysfunction.

Despite many recent advances, heart failure continues to be a major cause of morbidity and mortality in the United States. Once a patient is identified and evaluated as having heart failure, nonpharmacologic therapies such as a dietary restrictions, lifestyle changes, exercise strategies, and patient education are initiated as well as pharmacologic therapy. Angiotensin-converting-enzyme inhibitors, diuretics, and digoxin all are considered traditional therapy in the management of chronic heart failure associated with left ventricular systolic dysfunction. The role of newer therapies such as beta-blockers and angiotensin II receptor antagonists in the treatment of heart failure is in the process of being defined. Furthermore, new data is appearing concerning calcium channel blockers, spironolactone, and combinations of the various agents. Appropriate use of the traditional agents accompanied by a through understanding of the newer therapies and their roles is essential to the continued reduction of the morbidity and mortality associated with heart failure.

Adrenergic beta-Antagonists↗