Early failure of expanded polytetrafluoroethylene in femoral vein replacement.

Grafts of expanded 30-mu fibril length polytetrafluoroethylene (PTFE) were inserted as segmental femoral vein replacements in nine dogs. The contralateral femoral vein served as a control, receiving a graft from each dog's right external jugular vein. Graft patency was monitored for 24 weeks postoperatively with serial venograms and venous pressures of the operated limbs. All expanded PTFE grafts and one autogenous graft thrombosed within 24 to 48 hours. Significant venous hypertension in the extremities receiving the PTFE grafts persisted for six months.

A multicenter evaluation of the Boehringer Mannheim/Hitachi 717 system.

Analytical performance of the Boehringer Mannheim/Hitachi 717 system was evaluated in a multicenter study involving seven different laboratories. Fifty-five methods including end point chemistries, enzymes, ISE, TDM, DAU, and specific protein assays were assessed over a 7 month period. Methods on the analyzer exhibited excellent precision with CVs less than 2% for within run precision, and CVs less than 3% for between day precision for most analytes; linearity, which met or exceeded manufacturer's claims; minimal sample and reagent carryover, and no significant interference from hemolysis; icterus; and lipemia. Recovery of the assigned value for 10 analytes in SRM 909 was acceptable. Comparison of methods with other BM/Hitachi analyzers resulted in slopes close to unity (0.93-1.06); comparison to other clinical chemistry analyzers yielded slopes of 0.88-1.07. Excellent performance and diverse method applications make the BM/Hitachi 717 analyzer a suitable instrument for work station consolidation.

Bilateral linear subconjunctival hemorrhage in a trauma patient.

A case of bilateral linear subconjunctival hemorrhage secondary to a gunshot wound to the chest has been presented. The linear character was explained by cardiac tamponade and nearly instantaneous cessation of cardiac output.

An ameloblastoma with myofibroblasts and intracellular septate junctions.

This report represents a review of the ultrastructural features of the simple ameloblastoma. Our ultrastructural data indicate that the stromal component of ameloblastoma is composed of myofibroblasts with associated collagen and basal lamina material. A unique feature of these myofibroblasts is the formation of plaque-like structures on extended cell processes which were identified as intracellular septate junctions. The epithelial component of ameloblastoma was shown to be composed of three distinct cell types which appear to represent a continuum for the ameloblast-like basal cell through an intermediate to an acanthomatous cell. The actual relationship between the three cell types is unclear.