Search PubMed⌕ Search

Biomedical subjects

R E Lewis

Publications and source records attributed to R E Lewis.

At least 145 records · Page 8Linked to original sources

Right ventricular enlargement in heartworm disease.

The size of the right ventricle of 15 dogs with spontaneous Dirofilaris immitis microfilaria was evaluated by thoracic radiography, electrocardiography, and right ventricular free wall weights. Based on electrocardiography and right ventricular weights, none of the 15 dogs had evidence of right ventricular hypertrophy. Based on radiography, only 2 of the 15 dogs had right ventricles of normal size. Right ventricular dilation in the absence of right ventricular hypertrophy was demonstrated. The right ventricle appears to dilate, prior to hypertrophy, in response to D immitis infestation.

Animals↗

Contrast study of the gastrointestinal tract in the goat (Capra hircus).

Radiographic anatomy of the gastrointestinal tract of the goat (Capra hircus) was studied. Intraluminal contrast medium was used to evaluate the mucosal surfaces of stomach and intestines, and extraluminal contrast medium was used to evaluate the serosal surfaces of organs in the peritoneal cavity.

Abomasum↗

Susceptibility of dogs with heartworm disease to hypoxia.

Dogs with Dirofilaria immitis microfilariae and early radiographic pulmonary artery changes, but without pulmonary hypertension or clinical signs of heartworm disease, were studied. An exaggerated pulmonary hypertensive response was found in these dogs if subjected to 10% inspired oxygen. The mean pulmonary artery pressure of control dogs was increased from base line (prehypoxia control) of 15.8 +/- 2.3 (SEM) mm of Hg to 20.2 +/- 2.3 during hypoxia, and the mean pulmonary pressure of dogs with heartworm disease increased from base line of 16.4 +/- 2.4 to 26.4 +/- 1.6 during hypoxia. Pulmonary blood flow was not affected by hypoxia indicating that the increased pulmonary artery pressure was the result of increased pulmonary vascular resistance. There was an individual variation of this pulmonary hypertensive response of dogs with heartworm disease that did not appear related to the severity of the pulmonary arterial lesions, as evaluated by pulmonary arteriography.

Animals↗

Canine bone scanning: its use as a diagnostic tool for canine hip dysplasia.

The developing coxofemoral joint was evaluated in 7 dogs by means of pelvic scintigraphy (bone scanning) and pelvic radiography. Each procedure was performed monthly for 10 months to determine if early degenerative changes associated with canine hip dysplasia could be detected scintigraphically before they could be detected radiographically. At the end of the experiment, it was obvious that pelvic scintigraphy was a less sensitive tool for the diagnosis of canine hip dysplasia than pelvic radiography.

Animals↗

Hematologic and radiographic changes in cats after inoculation with infective larvae of Dirofilaria immitis.

Hematologic and radiographic findings in 15 domestic cats inoculated with 25, 100, or 200 to 400 infective larvae of Dirofilaria immitis and in 5 uninoculated cats were compared. Eosinophilia and leukocytosis developed 3 to 5 months after inoculation; packed cell volume and hemoglobin values were similar for inoculated cats and controls. Changes detected in radiographs of inoculated cats were: (1) increased visualization of the pulmonary arteries; (2) right-side cardiac enlargement; and (3) diffuse to focal areas of density in the pulmonary parenchyma. At least one of these lesions was visible radiographically by 3 to 7 months after inoculation in all 15 cats. The severity of changes was not directly proportional to the number of infective larvae inoculated, adult worm burden, or age of cat. However, male cats had more severe cardiopulmonary lesions than did females, and cats that had microfilaremia during the course of infection had more severe pulmonary lesions, as determined radiographically. Parenchymal densities decreased in 8 of the 15 inoculated cats 6 to 14 months after inoculation. Cardiac enlargement was detected radiographically in 10 of the inoculated cats. Enlargement of the pulmonary arteries was the most consistent sign of D immitis infection; it developed and persisted in 12 cats found to be infected at necropsy.

Animals↗

Effectiveness of coronary care units in small community hospitals.

A prospective study was undertaken from 1969 to 1974 to evaluate a program establishing coronary care units in small community hospitals. Crude mortality rates from acute myocardial infarction in these small hospitals were 14.5%, slightly higher but not statistically different from concurrently collected data in three larger comparision hospitals (11.5%). Mutivariate discriminate analysis of clinical characteristics was used to calculate a risk score for each patient admitted. Observed deaths exceeded expected deaths (134 versus 119) (P greater than 0.30) in small hospitals but observed deaths were less than expected (55 versus 77)(P less than 0.05) in comparison hospitals. Mortality was significantly greater in those units admitting fewer than 60 patients with infarctions yearly (20.9%) than in those admitting more than 60 (10.7%) (P less than 0.001). These data suggest that coronary care units in small community hospitals can provide adequate coronary care, but their level of performance drops when fewer than 60 patients with infarctions are admitted yearly.

Acute Disease↗

A review of the South American flea subgenus Ectinorus Jordan 1942, with descriptions of two new species and a key (Siphonaptera: Rhopalopsyllidae).

Ectinorus (E.) chilensis sp. n. from Abracoma bennetti and E. (E.) matini sp. n. from Aconaemys fuscus are described from collections from Chile. A diagnosis for the genus Ectinorus is given and differences between the nominate subgenus and the subgenus and the subgenus Dysmicus are briefly discussed. A key to the presently recognized species of the subgenus Ectinorus is included.

Animals↗