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S D Rockoff

Publications and source records attributed to S D Rockoff.

At least 37 records · Page 2Linked to original sources
PubMed1983

Physician attitudes toward the competence of general diagnostic radiologists: survey and implications.

Responses to a questionnaire were obtained from 1,539 physicians in 15 medical specialties to measure their attitudes toward general diagnostic radiologists in regard to their medical knowledge and professional competence as consultants. The data were evaluated in terms of the demographic profile of the respondents. Among the detailed results obtained, it was determined that only 8.1% of all physicians believe general diagnostic radiologists are poorly informed about disease processes, but 25% believe that these radiologists need more subspecialty training to be valuable as consultants to them. Physicians who do their own radiographic/sonographic examinations believe general diagnostic radiologists to be unimportant twice as often as do physicians who refer their patients to radiologists (28.2% vs. 14.5%). Most physicians (78%) believe that diagnostic radiologists perform unique functions in hospitals, while only 38% believe this to be true in the office setting. Consistent with this is that physicians practicing primarily in hospitals believe diagnostic radiologists need more training than do the primarily office-based physicians (29.6% vs. 16.8%). Of the specialists surveyed, orthopedic surgeons, neurosurgeons, cardiologists, and neurologists consistently had the lowest opinion of general diagnostic radiologists as consultants. In each of these specialties, less than 30% believed that general diagnostic radiologists are indispensable in the hospital setting. Also, younger (less than 45 years) physicians feel less dependent on general diagnostic radiologists than do older physicians. For example, twice as many younger physicians (17.3% vs. 7.9%) believe that diagnostic radiologists perform few or no unique functions which they cannot do themselves.

Ambulatory Care↗
PubMed1980

Protein-A antibody-binding TPAAB) technique for detection of tumor-associated membrane antigen (TAMA) of Lewis lung carcinoma.

Xenoantisera were prepared in rabbits against intact paraformaldehyde-fixed Lewis lung carcinoma (LLCa) cells and membrane solubilized proteins extracted with Triton X-100 and 3M KCI. The antisera were analyzed for antibodies to tumor-associated membrane antigens (TAMA) by means of a solid-phase radioimmunoassay (RIA). THe immunoassay employed 125-labelled Staphylococcus aureus protein A (SPA) to detect specific antibody binding to glutaraldehyde-fixed Lewis lung tumor target cells. The protein-A antibody-binding (PAAB) method is rapid, sensitive and reproducible. The PAAB revealed a possible LLCa-TAMA as evidenced by the reactivity of xenoantisera raised to LL paraformaldehyde tumor cell vaccine (TCV) and LL tumor Triton X-100 (TTri) and 3M KCI (TKCI) extracts of membrane preparations. The reactivity of our antisera followed linear dose-response kinetics but the degree of reactivity decreased from anti-TCV to anti-TTri to anti-TKCI respectively. The LL-TAMA demonstrated specificity since our antisera did not significantly cross-react with normal C56BL/6 cellular antigens or other known murine tumor-associated surface antigens of virally and chemically-induced tumor systems.

Animals↗
PubMed1980

Theoretical limitations in the immunodiagnostic imaging of cancer with computed tomography and nuclear scanning.

In order to help assess the feasibility of using immunologically tagged agents to render tumors detectable with current computed tomographic and nuclear scanners, mathematical formulations were developed to determine the theoretical limits of tumor detection relative to size and depth of the lesions. The results of our analysis suggest that visualization with computed tomography of a tiny tumor (1 sq mm, cross-sectional area) would require binding in the order of 2 x 10(5) iodine atoms/antigenic site, while imaging of a very large (900-sq mm) tumor would require approximately 10(4) atoms/site. Very low energy scanners might reduce these discouraging estimates by an order of 10(2). The immunological imaging of tumors with nuclear scanning appears quite feasible from our formulations, as has been demonstrated by others clinically. Small (1-sq cm) and deep (greater than or equal to 5-cm) tumors appear detectable with uptake ratios of the order of 5 or higher, which seem to be attainable currently. Smaller and deeper tumors require much higher uptake ratios to be detected.

Antibodies, Neoplasm↗
PubMed1979

Sensitive and convenient quantitation of antibody binding to cellular antigens using glutaraldehyde preserved cells.

As a preliminary step in the identification and isolation of antibodies to human cancers, we have developed a sensitive and convenient assay for antibody binding to cellular antigens. The basis for the method is antibody binding to glutaraldehyde-fixed cells (AbGfC) and quantitation with radioiodinated staphylococcal protein A (SpA). Glutaraldehyde fixation of intact cells, which does not appear to effect the ability to form antigen-antibody complexes, provides a convenient and standard supply of target cells which may be stored at 4 degrees C and used in the assay over a period of several months. The amount of antibody specifically bound to the cells is quantitated by the addition of 125I-labeled SpA. The sensitivity of the method was compared with two complement-dependent cytotoxicity methods (trypan blue exclusion and 51Cr release assays) and tested with two antisera to human lung cancer and one antiserum to a membrane antigen of a murine lymphoma. These comparisons indicated much greater sensitivity when compared with the trypan blue exclusion assay and equivalent sensitivity with greater dose response characteristics when compared with the 51Cr release assay.

Aldehydes↗
PubMed1977

The evolving role of computerized tomography in radiation oncology.

The development and application of computerized tomography of the body have important implications in the diagnosis of tumors and in the planning of the radiotherapy treatment of malignancies because the modality provedes: a) an exact contour of transverse sections of the body; b) distinct representation of anatomic internal structures; c) ability to diagnose the presence and extent of tumor involvement of internal organs; d) opportunity to obtain, quantitatively, the "density" (x-ray absorption) of the anatomical structures in the sections; e) capability to develop isodose curves with inhomogeneity corrections; and f) ability to follow the response of a tumor to treatment, non-invasively. Although the diagnostic efficacy of computerized tomography of tumors, relative to other diagnostic modalities, is still to be defined accurately and the exact role of this new method in radiotherapy treatment planning is still to be determined, computerized tomography appears to provide oncologists with a valuable adjunct in their management of tumor patients.

Adult↗