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Biomedical subjects

J T Tierney

Publications and source records attributed to J T Tierney.

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

Controlling physician oversupply through certificate of need.

By 1990 the aggregate supply of physicians in the United States is likely to exceed the population's requirements by 10 percent or more. State and regional aggregate and specialty-specific surpluses may be more extreme. Since the demand for physician services appears to be determined to a significant degree by the supply of physicians, the number of physicians who can maintain financially viable practices in a region is not likely to be limited effectively by the normal market interaction of supply and demand. Excessive physician supplies may, however, have a number of deleterious effects, including rapid escalation of health care costs, fragmentation of patient care, and a decrease in the quality of patient care. In this Article, the authors review the potential effectiveness of a number of policy interventions that might be employed to optimize physician supplies in areas of excess. They evaluate the following alternatives: (1) a limit on the number of medical school graduates; (2) control of physician residencies by number and by specialty; (3) creation or implementation of incentive policies; (4) control by hospitals--indirectly by limiting the number of beds, or directly by denying staff privileges; (5) widespread development of HMOs; (6) direct employment by the federal government of the majority of practicing physicians; and (7) creation of certificate of need for physician licensure is the alternative that shows the greatest promise of enabling the number and specialties of physicians providing patient care in areas facing a physician surplus to be managed in such a way that the populations of such areas can obtain adequate medical care at a reasonable cost.

Certificate of Need↗
PubMed1978

Potential sources of error during virus thermal inactivation.

A review of virus thermal inactivation data published in the literature demonstrated variations in reported virus resistance. Examination of the methods used indicated that numerous studies were made by heat processing virus suspensions in test tubes. Duplication of some of the methods using milk suspensions of poliovirus 1 showed virus persistence after heating as a result of uneven temperature distribution inside the test tubes. Unless the containers (preferably sealed ampoules or capillary tubes) are completely submerged in the water bath and agitated vigorously, apparent virus persistence may be encountered.

Animals↗
PubMed1977

Persistence of poliovirus 1 in soil and on vegetables grown in soil previously flooded with inoculated sewage sludge or effluent.

Land disposal of sewage sludge and effluent is becoming a common practice in the United States. The fertilizer content and humus value of such wastes are useful for agricultural purposes, and the recycling of sewage onto the land eliminates many of our stream pollution problems. The potential exists for crops grown in such irrigated soil to be contaminated by viruses that may be present in the sewage. Studies were initiated to determine viral persistence in soil and on crops grown under natural conditions in field plots that had been flooded to a depth of 1 inch (2.54 cm) with poliovirus 1-inoculated sewage wastes. Lettuce and radishes were planted in sludge- or effluent-flooded soil. In one study, the vegetables were planted 1 day before flooding, and in another they were planted 3 days after the plots were flooded. Survival of poliovirus 1 in soil irrigated with inoculated sewage sludge and effluent was determined during two summer growing seasons and one winter period. The longest period of survival was during the winter, when virus was detected after 96 days. During the summer, the longest survival period was 11 days. Poliovirus 1 was recovered from the mature vegetables 23 days after flooding of the plots had ceased. Lettuce and radishes are usually harvested 3 to 4 weeks after planting.

Poliovirus↗
PubMed1975

Collaborative study of the glass wool filtration method for the recovery of virus inoculated into ground beef.

A method for estimating viral population levels in ground beef was studied collaboratively in 7 laboratories. The collaborators recovered virus from 6 inoculated samples. Three samples were replicates of the high virus concentration 050 plaque-forming units (pfu)/g) and 3 replicates represented the low concentration (10 pfu/g). Six of the 7 collaborators recovered acceptable levels of virus from the samples. The per cent of variation was 30.6 for the high concentration and 18.5 for the low concentration. Collaborators did not differ from one another significantly in the results obtained for the 10 pfu/g samples, but results from one collaborator were significantly low for the recovery of virus from the 50 pfu/g samples. The results indicate that the glass wool filtration method is adequate for the detection of a number of viruses that may be found in foods. The method has been adopted as official first action.

Animals↗
PubMed1973

Comparison of methods for the recovery of virus inoculated into ground beef.

Various methods for the recovery of virus inoculated into ground beef were investigated in an attempt to develop a sensitive system that could be used to detect viral contaminants in market foods. A 100-g sample, inoculated with poliovirus 1, was suspended in 150 to 900 ml of Eagle minimum essential medium, pH 8.5, and mixed in either plastic bags or plastic cups on a mechanical shaker. The particulate materials were removed by means of cheese cloth, glass wool, woven fiber glass, or low-speed centrifugation. Large volumes of fluid were concentrated by ultrafiltration. Microbiological contamination was controlled by high antibiotic concentrations or by filtration. Quantitative plaque-forming-unit recovery of the virus was determined by utilizing an agar overlay technique on Vero cell cultures. The data indicated that from 20 to 50% of the seeded virus could be recovered from a 100-g sample of ground beef. The glass wool and woven fiber glass methods were the most effective, with recovery of approximately 50% of the inoculated virus.

Acetates↗
PubMed1971

Thermal resistance of certain oncogenic viruses suspended in milk and milk products.

Thermal destruction rate curves were determined for adenovirus 12, reovirus 1, and herpes simplex virus in sterile milk, raw milk, raw chocolate milk, and raw ice cream mix. At 40 to 60 C, the curves were asymptotic to the base line. At 65 C, which is near the pasteurization standard, the curves approached a first-order reaction. Thermal resistance studies, by means of in vivo assays, of Moloney and Rauscher leukemia viruses and Moloney and Rous sarcoma viruses indicated that Rous sarcoma was the most resistant. A comparison of the 12D processes of Rous sarcoma virus, reovirus 1, adenovirus 12, and herpes simplex virus in ice cream mix (the most protective of the suspending menstrua studied) with the U.S. Public Health Service pasteurization standard indicated an adequate safety factor in current pasteurization practices.

Adenoviridae↗