PubMed Health⌕ Search

Biomedical subjects

W H Kern

Publications and source records attributed to W H Kern.

At least 19 recordsLinked to original sources
PubMed1992

Diel patterns of cat flea (Siphonaptera: Pulicidae) egg and fecal deposition.

The quantity of eggs and feces deposited by replicate populations of cat fleas, Ctenocephalides felis (Bouché), from domestic house cats. Felis catus, were recorded at 1-h intervals over a 24-h period, in a photoperiod of 12:12 (L:D) (photophase, 0600-1800 hours [EST]). Egg production averaged 23.96 +/- 0.83 eggs per female per day and was greatest from 2400 to 0300 hours and lowest from 0700 to 0900 hours and from 1700 to 1900 hours. Daily fecal deposition was 0.77 +/- 0.03 mg feces per flea and did not vary significantly among hours. Flea eggs and adult feces were dropped continuously from infested cats, but significantly more eggs were shed at times of day when cats normally rest. More feces are concentrated in the small areas where cats rest than over the large areas they roam. Consequently, eggs and feces would not be deposited uniformly throughout the hosts home range, resulting in a clumped distribution of larval development sites at host resting areas.

Animals↗
PubMed1992

Spectrophotometric method of quantifying adult cat flea (Siphonaptera: Pulicidae) feces.

Cat flea, Ctenocephalides felis felis (Bouché), feces are an essential part of larval nutrition under natural conditions. The mass values of adult flea feces can be measured by dissolving samples of flea feces in Drabkin's reagent, filtering, centrifuging, and measuring absorbance spectrophotometrically at 540 nm. Either flea feces or air-dried host blood can be used to generate the standard curve used to convert absorbance (optical density) values into mass values. Debris collected from flea-infested house cats averaged 23.02 mg debris per cat per h with an average of 10.41 mg flea feces per cat per h. Flea feces deposited in the environment serve as potential larval food. Adult flea feces comprised an average of 44.28% of the debris deposited from infested domestic house cats in this study.

Animals↗
PubMed1988

Intraluminal thrombosis of coronary arteries in fatal myocardial infarctions and in failed aortocoronary saphenous vein grafts.

A review of autopsies of 648 patients who died of acute myocardial infarction showed the presence of intraluminal thrombi in 314 (48%). The left anterior descending coronary artery was principally involved in 172 cases, the left circumflex in 30, and the right coronary in 112. The length of survival after admission was identical for patients with thrombotic occlusion and those with atherosclerotic occlusion or severe stenosis: 28% of the former and 29% of the latter died during the first 24 hours after admission. The incidence of intraluminal thrombotic occlusion of surgically excised, failed aortocoronary vein grafts was 42 (66%) in 64 patients with nonfibrotic, patent grafts. Most of these vessels were severely atherosclerotic. The presence of intraluminal thrombi in about half of patients who died of acute myocardial infarction and in two thirds of excised, nonfibrotic, previously patent vein grafts indicates how many patients may benefit from thrombolytic therapy.

Coronary Artery Bypass↗
PubMed1986

Exfoliative and aspiration cytology of malignant lymphomas.

A cytologic diagnosis of malignant lymphoma based on fine-needle aspirates or body fluids can be made in 50% to 75% of cases. The diagnosis is more reliable for intermediate and high-grade lymphomas than for low-grade small lymphocytic or mixed small cell and large cell tumors. The cytologic evaluation is useful in the diagnosis of recurrence of a previously diagnosed lymphoma and in the determination of the stage, cavity involvement, and distinction between metastatic carcinoma and lymphoproliferative disease. The prognosis and to some degree the clinical management of lymphomas are based on the morphologic and often the immunologic classification. This initial diagnosis is best based on histologic, cytologic, and histochemical examination of surgically excised specimens.

Adult↗
PubMed1986

Needle aspiration cytologic examination in the management of suspicious lesions of the breast.

The experience of one surgeon with needle aspiration cytologic examination used as an office procedure in the management of suspicious solid lesions of the breast over a period of seven years in presented. Three hundred and thirty-five aspirations were performed with the diagnosis of carcinoma subsequently established in 126 or 37 per cent of the patients. In 79 of these patients (63 per cent) carcinoma was diagnosed preoperatively by positive needle aspiration cytologic examination only. There were no false-positive results. Thus, this group of patients was spared time and added expense of open biopsy before definitive surgical treatment was instituted.

Ambulatory Care↗
PubMed1985

Seminoma with elevated human chorionic gonadotropin. The case for retroperitoneal lymph node dissection.

An elevated serum level of human chorionic gonadotropin (HCG) in a patient whose primary tumor histologically appears to be a pure seminoma implies the presence of syncytiotrophoblastic giant cells either detectable by careful step sectioning of the primary tumor or present in metastatic disease. Inasmuch as the malignant potential and radioresponsiveness of syncytiotrophoblastic giant cells are unknown and the serum elevation of HCG may signal metastatic embryonal carcinoma, retroperitoneal lymph node dissection with adjuvant chemotherapy dependent on pathologic staging should be considered for patients with seminoma and postorchiectomy elevated HCG levels. An illustrative case is herein reported.

Adult↗
PubMed1985

Adenosquamous carcinoma of the lung: a clinical and pathologic study of seven cases.

Adenosquamous carcinoma is a rare, but pathologically distinct, form of lung cancer. Seven cases involving unequivocal squamous and glandular differentiation were studied. These cases accounted for 0.6 per cent of the 1,125 primary lung cancers examined at a metropolitan hospital during a 15-year period. The tumors measured from 1.3 to 5.5 cm in diameter. Five were peripheral, and two were associated with scars. Three of five resected specimens had regional lymph node metastases. Five patients had died of the disease within two years of diagnosis, and two were short-term survivors.

Adenocarcinoma↗
PubMed1985

Sarcoidosis presenting initially as breast mass: report of two cases.

The cases of two patients who presented with breast masses suggesting carcinoma and no other clinical features of sarcoidosis are reported. Biopsies in both patients revealed noncaseating, epithelioid granulomas. Mycobacteria, fungi, and foreign material were not identified. In one of the patients, other sites of involvement were discovered five years later. These cases illustrate that sarcoidosis should be considered in patients with granulomatous breast disease, even without evidence of disease elsewhere.

Aged↗
PubMed1984

The grade and pathologic stage of bladder cancer.

One hundred fourteen cases of bladder cancers treated during a 3-year period by cystectomy were uniformly reclassified, graded, and pathologically staged. One hundred thirty-one cases treated during the same period by transurethral or segmental resection were similarly reclassified and checked for muscle invasion. Sixty-one percent of the cystectomy cases were nonpapillary and 69% of the conservatively treated cases were papillary transitional cell carcinomas. In the pathologically staged cystectomy group, all poorly differentiated (grade III and IV) carcinomas were invasive. Nonpapillary tumors were more aggressive and 79% of the high grade tumors in these categories extended into the outer portions of the muscularis or into perivesical tissues. Muscle invasion could also be demonstrated in 74% of the 23 high-grade nonpapillary carcinomas in the conservatively treated cases. Lymph node and pelvic wall metastases were found in 17% of the cystectomies and were present only in tumor grades III and IV and a pathologic stage of P-3B or higher. None of the well differentiated (grade I) papillary carcinomas were invasive and invasion was superficial in most moderately differentiated (grade II) papillary tumors. The findings confirm that pathologic classification and grading of bladder carcinomas correlate closely with the stage of the disease.

Adolescent↗
PubMed1982

Hormone receptor levels and aspiration cytology in cancer of the breast.

The cytopathologic findings of 196 cases of cancer of the breast were correlated with the hormonal receptor levels. The strict cytologic criteria that allow a positive diagnosis to be used as bases for definitive treatment include adequate cellularity, lack of cohesion, and nuclear abnormalities, including increased nuclear size. On this basis, 58% of the carcinomas of the breast, including 62% of the 157 infiltrating duct carcinomas but none of 12 infiltrating lobular carcinomas, could be diagnosed by aspiration smears alone. Seventy-four per cent of the carcinomas were estrogen-receptor-positive. No correlation could be demonstrated between the cytologic pattern and diagnosis and the level of estrogen, progesterone, or androgen receptors, alone or in any combination.

Biopsy, Needle↗
PubMed1981

The pathology of surgically excised aortocoronary saphenous vein bypass grafts.

The pathologic features of 60 surgically excised failed aortocoronary saphenous vein bypass grafts from 40 patients were reviewed. In 23 cases the grafts were occluded by intimal fibrosis. In five this was associated with thrombotic occlusion of the remaining lumen. The histologic findings in some of these cases indicated that thrombosis preceded intimal fibrosis. Seventeen patients had graft failure caused by advanced arteriosclerosis. In 13 this was associated with thrombotic occlusion, often due to rupture of atheromatous plaques. The average duration of these grafts was 6--7 years compared to an average duration of 3 years for graft failure caused by occlusive intimal fibrosis, and 7 months for those associated with fibrosis and organizing thrombosis. Vein graft in the arterial circulation are susceptible to atherosclerosis; this becomes a significant problem after approximately 5 years. The pathologic changes closely resemble coronary arteriosclerosis.

Adult↗