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Biomedical subjects

H C Carlson

Publications and source records attributed to H C Carlson.

At least 37 records · Page 2Linked to original sources
PubMed1980

Upper abdominal abscess: a continuing and deadly problem.

Subphrenic and other upper abdominal abscesses continue to be associated with high mortality, even in today's era of broad spectrum antibiotics and sophisticated surgical techniques. Most cases represent complications of intraabdominal surgery. Because the clinical presentation is often subtle and nonspecific, the radiologist plays a paramount role in early diagnosis. Conventional radiography remains an effective method in the initial detection of upper abdominal abscesses. In this study, radiographs were reviewed in 82 patients. In retrospect, plain films revealed extraluminal gas or soft-tissue mass due to abscess in 58 patients (71%). Of these, the abscess was accurately reported initially in 42 patients, but it was initially missed in 16 patients. Conventional gastrointestinal contrast studies, which were underutilized, proved extremely accurate in demonstrating abnormality, especially in the left upper abdomen. Computed tomography, gallium scanning, and ultrasound were effective confirmatory procedures in many cases.

Abscess↗
PubMed1980

Physiopathology of lower esophageal diverticulum and its implications for treatment.

This study attempted to define the esophageal motor disturbances and pathogenesis of symptoms in patients with lower esophageal diverticulum. Sixty-five patients were investigated by manometry in addition to roentgenography and endoscopy. Fifty had manometric evidence of abnormal motility, most often diffuse spasm or achalasia. Of the 15 patients with normal esophageal motility, 13 had hiatal hernia, and five of these had a high grade distal esophageal stricture. Pressures in the lower esophagus and lower esophageal sphincter in patients with lower esophageal diverticulum and motor disturbance were the same as for those in matched patients with motor disturbances but no diverticulum. Dysphagia, chest pain and regurgitation were common presenting symptoms. Of 46 patients with dysphagia, only ten had mechanical obstruction to explain this symptom. Of 32 patients with chest pain, only two had ulceration in the diverticulum as a possible cause of pain. We conclude that the development of lower esophageal diverticulum and its symptoms are associated with a motor disturbance of the esophagus in the majority of patients and with an organic obstruction in the minority of patients. The diverticulum itself is usually not the sole cause of the esophageal symptoms, although diverticula can produce symptoms in the absence of other definable conditions. When surgical treatment is indicated, the diverticulum should be excised and the underlying motor or mechanical obstruction should be corrected to prevent serious postoperative complications and recurrence of the diverticulum and its symptoms.

Adult↗
PubMed1979

Pathological studies of "Sudden death syndrome" in broiler chickens.

Sudden death syndrome usually occurs in heavy, fast-growing and healthy-looking broilers. Most of the affected birds are males. The characteristic necropsy changes are seen in well-fleshed broilers with edema and generalized pulmonary congestion, recently ingested feed in the crop and gizzard, distended intestine with creamy content and empty gall bladder. The liver and kidneys are slightly enlarged and the latter have patchy areas of subcapsular hemorrhage. The heart contains clotted blood in the atria but the ventricles are often empty and the left ventricle in particular assumes a hypertrophied appearance. Microscopic examination of heart muscle reveals degeneration of fibers, separation of cardiac muscle fibers by edema and infiltration of heterophils. The lungs have severe vascular congestion, inflammatory cell infiltration in the mucosa of the secondary bronchi and edema fluid in the tertiary bronchi and interlobular connective tissue. The liver has moderate bile duct hyperplasia, periportal hepatitis and mononuclear cell infiltration adjacent to bile ducts which possibly leads to bile duct constriction. The kidneys have subcapsular and parenchymatous hemorrhage.

Animals↗
PubMed1979

Studies on effect of lighting on "Sudden death syndrome" in broiler chickens.

Broiler chicken flocks were studied to determine the mortality from sudden death syndrome occurring in the flocks. The difference in the incidence of the syndrome in pullets and cockerels, and the age at which the most birds are affected were also studied. The weight of sudden death syndrome birds was compared with the flock average and the effect of continuous lighting as opposed to intermittent lighting was examined. The results suggest that; continuous lighting produces more sudden death syndrome deaths than intermittent lighting; that the incidence of sudden death syndrome is higher in cockerels than pullets; that the highest death rate occurred during the third and fourth weeks of life, and that sudden death syndrome birds on the average were heavier than the flock average.

Animals↗
PubMed1978

Chronic ulcerative colitis and colon cancer: can radiographic appearance predict survival patterns?

Twenty-four patients with chronic ulcerative colitis and colon carcinoma who underwent barium enema examination prior to the diagnosis of cancer were studied in an attempt to correlate the radiographic appearance of the tumors with their biologic behavior, as well as to assess the accuracy of the barium enema in detection. Of the radiographically detected tumors, 65% displayed an annular infiltrative appearance, with the prime radiographic manifestation being relative nondistensibility of the involved segment. The remaining tumors had various appearances more typical of noncolitic colon cancer. Patients with infiltrative lesions had a much poorer prognosis than those with noninfiltrative lesions. Of 33 gross tumors described pathologically and/or surgically, only 70% were correctly detected by barium enema. It is suggested that periodic barium enema examinations are an unreliable means of following patients with ulcerative colitis if malignant degeneration is to be detected at an early and curative stage. Prophylactic proctocolectomy may be the best therapeutic approach.

Adult↗
PubMed1978

Salmonella investigation in an Ontario feed mill.

The frequency of Salmonella contamination of feedstuffs and finished broiler chicken feeds at an Ontario feed mill were investigated over a four-month period. Samples of feed ingredients and finished pelleted feeds were collected at various points during manufacture and cultured in trypticase soy broth prior to selective enrichment for isolation of Salmonella. Salmonella contamination was found in 4.3% of 93 finished pelleted broiler feeds examined. The contamination appeared to result primarily from the incorporation of contaminated animal protein ingredients into the feed. Meatmeal and the broiler, premix, which contained meatmeal as a filler, were most frequently contaminated followed by feather meal. Pelleting failed to eliminate the Salmonellae from the feeds. The methods used failed to detect Salmonella in the environment of the feed mill or its delivery trucks. Recommendations for control are made.

Animal Feed↗
PubMed1978

Sources of Salmonellae in broiler chickens in Ontario.

Sources of Salmonellae infecting broiler chicken flocks in Ontario were investigated from July, 1975 to April, 1976. Three broiler flocks were investigated on each of four farms which received chicks from a common hatchery. Samples of feed and new litter were preenriched in nonselective broth subcultured to Salmonella-selective enrichment broth and plated on Salmonella-selective differential agar. Samples of used litter, water, culled chicks, insects, mice, wild birds and environmental swabs were not cultured initially in the nonselective broth. Fecal samples from principal and occasional flock attendants were examined for Samonellae. Salmonella infection, as judged by contaminated flock litter was detected in six flocks on two of the farms while the flocks on the other farms remained negative. Salmonellae were isolated from 23 of 412 feed samples (nine serotypes), six of 35 new wood shaving samples (four serotypes), one of 29 pools of culled chick viscera (one serotype) and 44 of 267 used litter samples (14 serotypes). These results indicate that broiler chicken flocks were infected with diverse Salmonellae introduced in day old chicks, pelleted feeds, wood shavings and residual contamination from the preceding flock.

Animal Feed↗
PubMed1977

Secondary neoplasms of the small bowel.

Patterns of small bowel involvement from primary neoplasms elsewhere in the body were studied in order to determine whether the location of the lesions or their radiological appearance could provide criteria for distinguishing secondary from primary lesions. Multiplicity of lesions and the finding of "transverse stretch" were found to be highly indicative of secondary neoplastic involvement of the small bowel.

Humans↗
PubMed1977

The effect of an alexidine mouthwash on dental plaque and gingivitis.

The alexidine mouthrinse used in this study (CP-101) is effective in reducing plaque. There was a reduction in gingivitis after 6-months use but not at a statistically significant level. An extrinsic brown stain occurred at a significant level on the teeth of participants using the active mouthrinse. Blood and urine laboratory results indicated that alexidine can be safely used over a 6-month period.

Adolescent↗
PubMed1977

Antimicrobial susceptibility of Salmonella isolates from the broiler chicken industry in Ontario.

Antibacterial drug resistance among 219 salmonella isolates recovered during 1974 from poultry and poultry environments at the various production stages of broiler chickens in three integrated Ontario companies are recorded. All isolates were susceptible to ampicillin, trimethroprim-sulfamethoxazole complex, furazolidone, cephaloridine and amoxicillin. A relative increase in resistance to tetracycline and streptomycin with an accompanying decrease in resistance to triple sulfa compound was recorded when compared to a previous investigation of avian salmonella isolates in Ontario. The percentage and patterns of antimicrobial resistance were comparable at the various stages of production. Resistance to tetracycline and streptomycin was the most common pattern found among both Salmonella typhimurium and other serotypes. A notably high prevalence of resistance was found among Salmonella enteritidis isolates including some isolates with R factors for chloramphenicol resistance. This latter finding is of particular concern because of the high prevalence of this serotype in poultry and in human salmonellosis.

Animals↗
PubMed1976

Tomography of the gallbladder in oral cholecystography.

Tomography was used to supplement 327 oral cholecystograms in which the findings, including nonvisualized gallbladder, were inconclusive. In 136 cases, operative and tomographic findings were correlated. In 286 cases (87%), tomography provided conclusive diagnostic information. A diagnosis was possible in 108 of 111 cases in which the gallbladder had been visualized on conventional films and in 179 of 216 cases in which the gallbladder had not been visualized. Tomography of the gallbladder is an easily accomplished procedure that usually adds enough information to the inconclusive cholecystogram to permit accurate diagnosis and eliminate the need for reexamination.

Adult↗
PubMed1976

Passive cutaneous anaphylaxis in the domestic fowl.

Passive cutaneous anaphylaxis (PCA) has been demonstrated in young and adult domestic fowl using antisera obtained from actively sensitized chickens on the day of their maximal susceptibility to systemic anaphylaxis. Young chickens are more sensitive to histamine and PCA reaction than adults. The PCA reaction was inhibited by the H1-histamine receptor blocker, mepyramine. In the PCA reaction of 2 h sensitization period, the main exudating cells were heterophils, mononuclear cells (lymphocytes, monocytes and macrophages) and some basophils. This study suggests a possible role for circulating basophils in the mediation of early acute inflammatory reaction of immunological origin.

Aging↗
PubMed1976

Specificity of 99mTc-pertechnetate in scintigraphic diagnosis of Meckel's diverticulum: review of 100 cases.

Numerous reports in the recent literature have questioned the value of abdominal scanning with pertechnetate in the diagnosis of Meckel's diverticulum. In an attempt to evaluate further the specificity of pertechnetate in this condition, the clinical data and scintigrams of 100 patients with suspected Meckel's diverticulum were reviewed. The scintigram correctly identified Meckel's diverticulum before operation in seven of eight patients. One false-negative study occurred in 33 patients who underwent laparotomy. Conditions suggested as possible causes of false-positive studies (hydronephrosis, arteriovenous malformations, and intussusception) were found to give negative scans.

Adolescent↗
PubMed1975

The roentgenographic and clinical findings in Whipple's disease. A review of 8 patients.

Out of 8 patients with Whipple's disease, 7 had roentgenographic findings consisting of slight dilatation of the small bowel, with thickening of the mucosal folds. The eighth patient had no abnormality on roentgenographic study. This series represents the first in which the roentgenographic changes have been quantitatively assessed. Confirmation of the diagnosis by biopsy is important because antibiotic treatment results in marked improvement both clinically and roentgenographically.

Adult↗