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Biomedical subjects

J B Shields

Publications and source records attributed to J B Shields.

At least 37 records · Page 2Linked to original sources
PubMed1981

Radioimmunoassay of PCBs in milk and blood.

A radioimmunoassay was developed capable of determining Aroclor 1260 in milk at levels of from 20 to 80 ppb and in blood from 2 to 16 ppb. The values obtained by radioimmunoassay correlate well with those determined by gas-liquid chromatography (r2 = 0.96 for milk and 0.99 for blood) but were lower. Antiserum was produced in rabbits and was specific for 2,2',4,4',5,5'-hexachlorobiphenyl. It cross-reacted with congeners and isomers in Aroclor 1254 and 1260 to the extent that a 20% decrease in binding was observed with 0.1 ng of either mixture. The method requires preliminary cleanup of the extract on alumina and utilizes 25% dimethyl sulfoxide in the assay medium to promote solubilization of the substrates.

Animals↗
PubMed1979

Terminal phalangeal tufts: earliest site of renal osteodystrophy findings in hemodialysis patients.

Direct magnificaiton of the hands of 44 patients on maintenance hemodialysis showed that the earliest unequivocal changes of renal osteodystrophy occur in the tufts. Some workers made a similar observation, but no previous objective study confirmed or refuted the sensitivity of the tufts in the diagnosis of renal osteodystrophy. The macroradiograph is consistently reproducible and serves as an excellent visual record of subtle changes.

Chronic Kidney Disease-Mineral and Bone Disorder↗
PubMed1979

CT as a primary diagnostic method in evaluating intraabdominal abscess.

In 19 cases, a correct diagnosis of intraabdominal abscess was made by CT body scanning. There was one false-positive diagnosis and initially one false-negative diagnosis. CT proved to be an efficient imaging method for diagnosis, for planning of therapeutic procedures, and in monitoring response to operative or conservative treatment. It has advantages over ultrasound and gallium scanning especially in severely ill, postoperative, and obese subjects. In addition, needle aspiration under CT control is readily performed and can be undertaken at the same examination. Confirmation of the diagnosis and therapeutic aspiration with or without introduction of a drainage catheter can then be undertaken.

Abdomen, Acute↗
PubMed1977

Hexachlorobenzene residues and effects on esterase activities in pre-weanling rats after a reciprocal transfer between HCB-treated and control dams.

Female Wistar rats were divided into two groups. One group was fed ad libitum powdered rat chow containing 80 ppm hexachlorobenzene (HCB) and the other was fed HCB-free diet 2 weeks before mating until the termination of the experiment. Immediately after parturition, the pups were randomly culled to 10 per litter and 5 pups were reciprocally transferred between HCB and control dams. All pups within same paired litters were sacrificed on the 16th to 17th day and on the 20th to 23rd day after birth. Liver esterase activity toward indophenyl, thiophenyl, and p-nitrophenyl acetates was determined. The liver to body weight ratio, liver esterase activity and HCB residues were significantly higher in pups nursed by HCB-fed dams than in those nursed by control dams. The HCB residue in the liver, kidney, spleen, heart and brain was analyzed by gas-liquid chromatography. At about the weaning time, the HCB residue levels in pups transferred after parturition from HCB fed to control dams were similar to those in pups which remained with the control dams. The results demonstrated that HCB in tissues at about weaning time was obtained largely through milk. In addition, transmission of HCB through milk had greater effects on esterase activities in suckling pups than placental transmission. The pups born to HCB-treated dams and nursed by the control dams were similar to the pups born and nursed by the same control dams.

Animals↗
PubMed1976

The retrotracheal space.

The retrotracheal space may be abnormal when a frontal chest radiograph is normal. Common abnormalities, seen usually on the lateral view, are widening of the anterior soft tissue stripe separating the tracheal air column from the clear space behind it, and a mass density overlying the space. A barium esophagram generally facilitates the diagnosis.

Radiography↗
PubMed1975

Liver scanning and the intrahepatic gallbladder: Case report.

Hepatic focal defects identified with 99mTc-sulfur colloid imaging procedures are nonspecific. This report describes a case of an ectopic gallbladder localized by cholecystography and 131I-rose bengal studies in a patient with cirrhosis and suspected intrahepatic neoplasm.

Colloids↗
PubMed1975

Misplacement of central venous pressure catheters and unilateral pulmonary edema.

Two instances of misplacement of a central venous pressure monitoring catheter into a pulmonary artery are presented. In one case, reported in detail, unilateral pulmonary edema developed during administration of 0.5N saline for the treatment of diabetic acidosis via the misplaced catheter, and it reverted following repositioning of the catheter in the superior vena caca. Experiments were carried out in dogs to explore possible causes of this phenomenon. The results of these experiments suggest that the release of vasoactive substances, stimulation of neural reflexes, or both are the pathophysiological mechanisms responsible for the development of the pulmonary edema.

Animals↗
PubMed1975

Body burden of hexachlorbenzene in suckling rats and its effects on various organs and on liver porphyrin accumulation.

The hexachlorobenzene (HCB) and porphyrin accumulation in the ograns of 18-day-old Wistar rats, whose mothers were fed a diet containing 80 ppm HCB, were studied. Among the organs examined, the highest HCB residue was in the liver larger than kidney larger than or equal to lung larger than brain larger than spleen larger than heart. The porphyrin level in the liver of the HCB-treated. On the contrary, the weights of the kidney, brain, spleen and heart were significantly reduced. Sex did not influence the organ weight except that of the brain. The results suggested that accumulation of HCB in different organs and porphyrin in the liver of suckling Wistar rats was about equal for the males and females.

Animals↗