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W J Nalesnik

Publications and source records attributed to W J Nalesnik.

4 recordsLinked to original sources
PubMed1991

Effects of varying potential and electrolytic dosage in direct current treatment of tumors.

The effects of different voltages and dosages during direct current treatment were studied to determine the most effective tumor treatment. Groups of nude mice with subcutaneous human colon cancer nodules were treated with a single electrolytic dose (charge) of direct current using two percutaneously placed needle electrodes. All the treated groups responded and the residual tumor volumes were significantly lower (p less than 0.001) than the control group. 7.5 V gave the greatest tumor reduction, significantly more than for 12.5, 10.0, and 2.5 V. 35 C/ml of tumor was more effective than 30 C/ml (p less than 0.05) and no difference in response was obtained between 35 and 50 C/ml. Hyperthermia did not appear to play a significant part in direct current treatment in the examined voltage range as no intra-tumoral temperature elevation was observed. Direct current may allow effective percutaneous treatment of metastases which are unresponsive or unsuitable for conventional treatment.

Animals↗
PubMed1981

Three- tier rare-earth imaging system.

The increased efficiency of gadolinium oxysulfide intensifying screens as compared to calcium tungstate screens depends primarily on increased absorption of x-ray photons coupled with a twofold increase in light output. Whether this increased efficiency can be effectively used in a routine diagnostic department to significantly decrease radiation dose was the subject of this study. Consecutive radiographic examinations (5,806) were conducted using these "rare earth" screens. Each radiographic room used three individual rare earth screen/orthochromatic film combinations in order to obtain different speeds. These were labeled A, B, and C and ranged from "par" speed high detail to "ultra high" speed with less detail but correspondingly less patient radiation exposure. The system selected for a particular examination was based on the radiologists' requirements for imaging of anatomic detail. Those examinations requiring less detailed resolution (such as bone alignment through a wet plaster cast) were assigned the fastest speed available. The use of a rare earth/3-tier system resulted in an overall reduction in radiation exposure of about 80%.

Child↗
PubMed1980

CT in localization of impalpable cryptorchid testes.

Computed tomography was used for preoperative localization in 12 patients with undescended testes. Because three patients had bilateral involvement, 15 absent or undescended testes were studied. Surgical confirmation of the CT findings was obtained in 12 instances. Confirmation was not obtained in one patient who refused operation and it was considered incomplete in another due to limited surgical exploration. There was one incorrect localization. The procedure is quick, simple, noninvasive, and can be performed at all ages. The testicular radiation exposure was considered acceptable on the basis of phantom measurement. The lowest possible exposure factors were used on all patients. CT findings assisted planning of operative procedures and in some cases enabled more limited and shorter operations.

Adolescent↗