The puckered panniculus--a sign of previous surgery.

On abdominal radiographs, the fatty panniculus, if present, has two possible configurations: firstly, a smooth, uniformly convex bow which is the normal appearance; or secondly, a bow with a central indentation (broken bow). This latter is a useful radiographic sign of previous lower abdominal surgery. The central indentation is created by tissue tethering around the laparotomy scar.

The "inverted V" sign of pneumoperitoneum.

On the supine radiograph, an inverted "V" may be seen over the pelvis in a patient with pneumoperitoneum. While in infants this is produced by the umbilical arteries, in adults it appears to be created by the inferior epigastric vessels.

Encoding variability theory and the spacing effect in associate learning.

Encoding variability theory accounts for the spacing effect by assuming that, as the lag between repetitions increases, the memorial representations approach independence. A method for testing this assumption in determining repetition effects in associative learning is suggested. In the independence hypothesis, we simply assume that each presentation of a word pair is represented independently, so that the expected proportion recalled is simple, P=P1+P2 - PIP2. Two studies are reported using a continuous paired-associate task representing a factorial combination of lag and retention interval as well as single-presentation control conditions. The results indicate that for moderately long retention intervals, as the lag between repetitions increases, the observed proportion recalled is first less, then eventually exceeds, and then returns to the level expected by an independence hypothesis.

Percutaneous biliary drainage: complications of 118 consecutive catheterizations.

We have reviewed our experience with 118 biliary catheterization procedures in 109 patients from 1979 to 1984. Major complications (septic shock, hemorrhage, subphrenic abscess, and formation of an arteriovenous fistula) occurred in five patients (4.2%), three of whom died (2.5%). Minor complications occurred in 41 patients. Our success rate using the procedure was 97%. The complications that occurred are described.

One hundred consecutive laparoscopic cholangiograms. Results and conclusions.

BACKGROUND: In 100 consecutive patients who underwent laparoscopic cholecystectomy, the feasibility, reliability, and cost of routine laparoscopic cholangiography were prospectively studied. METHODS: Fluoroscopic cholangiograms with multiple exposures were successfully completed in all patients in an average time of 6.9 min. RESULTS: Twenty-one percent were abnormal, and 15 common duct stones and 6 significant anatomic anomalies detected. Thirteen out of 15 patients with common duct stones had preoperative suspicion of common duct stones. Two out of 15 were completely unsuspected. The average cost of cholangiography was $768, and there were no complications related to the procedure. There were no false interpretations. CONCLUSIONS: When compared with selective preoperative endoscopic retrograde cholangiopancreatography (ERCP), routine laparoscopic cholangiography is safer, more accurate, and less costly, and may have the added benefit of potentially reducing iatrogenic injuries in patients with anatomic variations. Routine laparoscopic cholangiography should be considered by all surgeons.

The radiographic appearance of erosive duodenitis: a radiographic-endoscopic correlative study.

We studied 12 patients who had had endoscopically proved erosive duodenitis and a radiographic examination of the upper gastrointestinal (UGI) tract, which had been performed within 2 weeks of endoscopy. Radiographic criteria for erosive duodenitis were established by two radiologists and consisted of spasm, thickening of duodenal folds, erosions, and ulcers. Using these criteria, two other radiologists interpreted the radiographs of the 12 patients with duodenitis 15 others with normal duodenums, and five with pancreatic disease. They made correct diagnoses for eight of the patients with erosive duodenitis, nine with normal duodenums, and three with pancreatic disease. A third radiologist interpreted only the 12 misdiagnosed radiographs; he was correct only for three cases of duodenitis. Analysis of these results show that radiographic diagnosis of erosive duodenitis can be made only in advanced disease.

Detection of bluetongue virus serotype 17 in Culicoides variipennis by nucleic acid blot and sandwich hybridization techniques.

Molecular hybridization techniques were developed for the detection and surveillance of bluetongue virus (BTV) serotype 17 in the insect vector Culicoides variipennis, a biting midge. Radiolabeled RNA and cDNA probes were generated from sequences of the L3 segment of BTV serotype 17. These probes were used to detect BTV RNA in pools of infected C. variipennis by hybridizing the probes directly to analyte immobilized on nylon membranes or by using a nucleic acid sandwich hybridization test. Hybridization procedures were able to detect 1 infected C. variipennis in a pool of 50 and as little as 3.55 log10 50% tissue culture infective doses per ml of virus. These hybridization techniques provide an alternative to virus isolation for the surveillance of BTV in vector populations.

Trioxane dimers have potent antimalarial, antiproliferative and antitumor activities in vitro.

A series of tetracyclic and tricyclic trioxane dimers has been prepared with ether and ester tethers of varying length and flexibility. Several of these trioxane dimers have been found to have potent and potentially therapeutically valuable antimalarial, antiproliferative, and antitumor activities in vitro.