Publications by authors named "Wittenberg J"

A method for assessing the effect of computed body tomography on diagnostic understanding and therapeutic decision making is described and the results in the first 184 patients are presented. The patients' referring physicians provided the primary data used for the evaluation. CT improved diagnostic understanding in 41% of patients, reassured the physician about previously planned therapy in 43%, contributed to a change in therapy in 17%, and improved precision of previously planned treatment in an additional 10%.

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Clinical examinations with the whole body CT scanner require considerable individualization of examination technique in relation to specific organs, anatomic areas, and clinical problems. Careful selection of radiographic factors, patient position, contrast agents, and pharmacologic adjuncts will optimize diagnostic results and patient throughput.

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Computed tomographic (CT) images of in vitro hearts filled with iodinated contrast medium have delineated right and left ventricular cavities, papillary muscles, major trabeculae, pulmonary artery, and the aorta. Because of relatively good structural definition, this study was undertaken to determine the potential use of CT in the measurement of cardiac dimensions and cavity volumes. Ten isolated arrested canine hearts were filled with an iodinated oil-paraffin mixture and scanned transversely from base to apex.

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The recent wide acceptance of Chiba needle transhepatic cholangiography prompted this elaboration of present techniques, intraprocedure observations, and special interpretive considerations based on a series of 100 consecutive examinations. The established safety margin of this technique now permits up to 15 needle passes to obtain a cholangiogram; thus success rates of duct opacification presently approach 100%. Special phenomena related to the small caliber of the needle include duct filling from "invisible" radicles, perivenous or periductal dissection of contrast, and pseudolesions in an incompletely decompressed stagnant bile column.

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Computerized axial tomography of the brain is a revolutionary noninvasive technique that has provided remarkable resolution of intracerebral structures. This study was undertaken to determine the potential of computerized tomography for defining the anatomy of 40 arrested and 9 beating (ejecting left heart preparation) canine hearts. Using an EMI cranial unit, scanning was performed in hearts under in vitro conditions with a lactated Ringer's interface.

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The capacity of computerized tomography to assess myocardial edema resulting from acute coronary occlusion was investigated in 19 arrested and 2 beating canine hearts. Edematous myocardium was consistently detected as areas of decreased attenuation values. The magnitude of the decrease in attenuation value was linearly related to the severity of the edema.

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This study was undertaken to determine if computerized tomography (CT scanning) with an EMI cranial scanner could detect edema associated with myocardial ischemia in canine hearts. A localized area of decreased density in the posterior papillary muscle and surrounding myocardium was detected on serial 8 mm CT scan slices of each heart after 60 min of circumflex artery occlusion and 45 min of reflow of blood. The wet/dry weight ratios and previous electron microscope studies of the ischemic posterior papillary muscles revealed edema accumulation.

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The effect of formalin, freezing, and refigeration on the attenuation coefficient of fresh abdominal tissue of rhesus monkeys and dogs was investigated over a 1-week period. These techniques were used individually and in combinations designed to simulate circumstances involved in future in vitro investigations of human specimens. Statistically significant alterations of attenuation coefficients were found to occur at all scanning times within the first week except for the first 48 hr of formalin storage.

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Oxygen uptake of fully deoxygenated sickle (SS) erythrocytes is slower than that of normal (AA) erythrocytes, as demonstrated by the half-times of the overall oxygenation reactions: at 25 degrees in an isotonic phosphate buffer the normal red cells have a t1/2 = 82 +/- 4.7 msec, as compared to sickle red cells where t1/2 = 135 +/- 17.6 msec.

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Electron paramagnetic resonance (EPR) and optical spectra are used as probes of the heme and its ligands in ferric and ferrous leghemoglobin. The proximal ligand to the heme iron atom of ferric soybean leghemoglobin is identified as imidazole by comparison of the EPR of leghemoglobin hydroxide, azide, and cyanide with the corresponding derivatives of human hemoglobin. Optical spectra show that ferric soybean leghemoglobin near room temperature is almost entirely in the high spin state.

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Transhepatic cholangiography performed with a newly introduced fine caliber (0.7 mm OD) "Chiba" needle produces a significantly higher success rate of biliary duct opacification with fewer complications than conventional needle or flexible cannula techniques. Distinct advantages over endoscopic retrograde cholangiography are also apparent, including more frequent bile duct opacification, ease of performance, and lower overall cost.

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The effect of vitamin A deficiency and hypervitaminosis A on the urothelial carcinogenicity of N-[4-(5-nitro-2-furyl)-2-thiazolyl]formanmide (FANFT) was determined in female weanling Sprague-Dawley rats. Vitamin A deficiency resulted in squamous metaplasia of the urinary bladder and high incidences of cystitis, ureteritis, and pyelonephritis. Administration of FANFT to vitamin A-deficient rats appeared to accelerate the carcinogenic process, with earlier appearance of urinary bladder tumors and the development of ureteral and renal pelvic carcinomas.

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Hypotonic cholangiography was performed with intravenous glucagon in 12 patients who demonstrated complete nonspecific obstruction of the distal common bile duct during postoperative T-tube or transhepatic cholanglography. In 8 cases (67%), a diagnostic result was obtained. Abolition of smooth-muscle spasm at the choledochal sphincter by glucagon-induced hypotonia appears to be a useful adjunct to roentgenography of the bile ducts.

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One-hour infusion intravenous cholangiography with iodipamide was performed in 3 rhesus monkeys with intact enterohepatic circulations. A series of four different doses including standard (0.3 ml/kg) and "double dose" (0.

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Four cases of ischemic colitis occurring at intervals from 3 months to 7 years after abdominoperineal resection are described. In 3 of the 4 cases patency of the direct arterial supply to the ischemic segment was documented. The lack of collateral circulation provided by the resected colon probably increases the risk of developing ischemic colitis in the remaining colon.

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The contribution of nyoglobin to the oxygen uptake of red skeletal muscle was estimated from the difference in oxygen uptake with and without functional myoglobin. The oxygen uptake of bundles (25 mm long, 0.5 mm mean diameter) of muscle fibers teased from pigeon breast muscle was measured in families of steady states of oxygen pressure from 0 to 250 mm Hg.

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B-mode ultrasound examinations have been useful in demonstrating cholelithiasis and obstructive dilatation of the gallbladder. It is now possible with gray scale ultrasound technique to demonstrate dilatation of the common bile duct, as differentiated from the gallbladder, and also to show fluid containing spaces within the liver. Discrimination between solid and fluid filled intrahepatic structures is readily made, and dilated biliary radicles are frequently discernible.

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A patient with a clinical and angiographic diagnosis of nonocclusive mesenteric ischemia had phenoxybenzamine directly infused into the superior mesenteric artery to counteract the existing splanchnic vasoconstriction. The diagnosis was confirmed by later operative intervention and the patient recovered. Vasodilatory drugs may play a significant role in the management of patients with nonocclusive mesenteric ischemia.

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