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A Steinbach

Publications and source records attributed to A Steinbach.

8 recordsLinked to original sources

The role of staging bronchoscopy in the preoperative assessment of a solitary pulmonary nodule.

In order to assess the role of a staging fiberoptic bronchoscopy in the preoperative assessment of an indeterminate solitary pulmonary nodule (SPN), we reviewed our experience in 33 SPNs identified among 1,269 bronchoscopies performed at the Albert Einstein Medical Center between 1985 and 1989. All lesions were less than 4 cm in greatest diameter and were not associated with symptoms of weight loss, chest pain, hemoptysis, localized wheezing, or hoarseness. A tissue diagnosis was established in 25 patients, 23 of whom had a malignant SPN. This study failed to detect a single case in which a fiberoptic bronchoscopic examination of the airway discovered a lesion that would preclude surgery and potentially curative resection. We recommend the abandonment of a staging bronchoscopy in the evaluation of a patient with an indeterminant SPN in whom history, physical examination, laboratory, and imaging studies fail to document contraindications to surgery. No additional useful information is derived and a substantial cost savings to the patient can be realized if the procedure is eliminated.

Adenocarcinoma

Effect of hyperbaric oxygen exposure on oxygen tension within the medullary canal in the rabbit tibial osteomyelitis model.

The effect on intramedullary oxygen tension of 100% oxygen exposure at 1, 2, 2.4, and 3 atm pressure was studied in 12 New Zealand white rabbits with chronic right tibial osteomyelitis. The model, modified from that described by others, incorporates a multipuncture silastic closure plug placed transcortically in the proximal tibial metaphysis through which platinum needle, polarographic electrode oxygen tension determinations can be made without repeat surgical exposure. In 40% of the control, left, noninfected tibial metaphyses the baseline oxygen tension with the animals breathing room air at sea level was suboptimal for leukocyte bacterial killing. This oxygen tension was depressed further in the infected right tibia. Medullary canal oxygen tension increased in response to hyperbaric oxygen exposure in both the infected and noninfected tibiae. Whereas the amount of the oxygen tension increase varied with the presence of infection and depth of dive, neither the time for oxygen tension to plateau nor the time required for return to baseline tension after completion of hyperbaric oxygen exposure varied with the presence of infection or depth of dive. After completion of hyperbaric oxygen exposure, the oxygen tension within the medullary canal returned to baseline within 15 min.

Animals

Neutron microscopy. The low-damage imaging of specialized organic materials.

It is shown that, insofar as radiation damage is concerned, transmission neutron microscopy using neutrons in the energy range approximately 0.0001-1.0 eV is extremely attractive for the imaging of specialized organic materials. By "specialized organic materials" is meant organic specimens composed entirely of specific isotopes that have been selected on the basis of their favorable properties with regard to radiation damage. In connection with such specimens, it is demonstrated that at a resolution of, for example, 100 A, neutrons will have an advantage over soft X-rays in terms of radiation damage, provided that the inherent (neutron) bright field image contrast turns out to be greater than 10(-5). Suggestions relating to (a) the comprehensive calculation of the radiation damage sustained by specialized organic specimens under slow neutron irradiation, (b) the construction of a theory of image formation in the neutron microscope, (c) the development of neutron lenses/focusing devices, and (d) the development of a brighter neutron source (essential for neutron microscopy) are outlined in some detail. The paper concludes with two appendices, which provide important background material.

Animals

Pap smear adequacy.

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Female