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991.
The successful use of guided percutaneous needle aspiration in the management of four patients with solitary splenic abscess is described. Two patients had needle aspiration alone and two patients, with large splenic abscesses, had drainage tubes inserted. The procedures were well tolerated and allowed rapid microbiological diagnosis with selection of appropriate antibiotic therapy. The techniques were useful in patients felt to be poor anaesthetic risks, and the complications of splenectomy were avoided.  相似文献   
992.
We have used tissue expanders to treat 10 patients with breast deformities, 2 the result of burns and 8 congenital in origin. The expanders are placed in the subglandular plane and expanded incrementally until the desired amount of growth is obtained. In patients with congenital deformities, the desired size of the reconstructed breast (implant size) is determined during the expansion phase. Reconstructions of the nipple-areola complex are done either at the time of the exchange or as separate procedures. Patients with burn deformities present a variety of problems not seen with the congenital deformities. The expander is placed in the subglandular plane and filled to the desired volume. We have noted a marked permanent softening of the scar and grafts encasing the breast, which persists after the expander is removed and the breast reconstructed. The interval between expansion and definitive reconstruction is delayed for several months to allow scar softening to take place. If the parenchyma is not burned and pedicle tissue is not required, the expander can be deflated and the skin coverage observed to determine if it will remain soft. If it does, the expander can be removed and the breast reconstructed. In patients who require pedicle coverage in the reconstruction and who have unburned scar surrounding the breast, massive overexpansion is carried out. The pedicle skin is used to resurface the breast after removal of the appropriate areas of scar and skin grafts. In all burned patients, the inframammary fold must be reconstructed if the breast is to be protuberant. The nipple-areola complex also requires reconstruction. To date there has been great acceptance by patients with both congenital and burn deformities; however, we believe that tissue expansion techniques offer possibilities that have not as yet been fully explored.  相似文献   
993.
994.
A new technetium-chelating agent based on a triamide monomercaptide tetradentate set of donor groups, mercaptoacetylglycylglycylglycine (MAG3), was synthesized and evaluated. Chelation with 99mTc resulted in a single radiochemical product as expected. Studies in mice of [99mTc]MAG3 indicated excretion rates faster than omicron-iodohippurate (OIH) both in normal and in probenecid treated animals. Specificity for renal excretion was essentially complete. Clearance studies in rats resulted in 2.84 ml/min/100 g for [99mTc]MAG3, 2.17 for OIH, and 1.29 for [125I]iothalamate. Extraction efficiencies were 85% for [99mTc]MAG3, 69% for OIH and 39% for [125I]iothalamate. Probenicid depressed the clearance both of [99mTc]MAG3 and OIH at 25 and 50 mg/kg/hr, but to a greater extent with [99mTc]MAG3. The greater effect is offset, however, by the larger fraction secreted by the renal tubular cells. The animal results suggest that [99mTc]MAG3 may be a useful alternative to [131I]OIH.  相似文献   
995.
996.
Results of three therapeutic modalities used for the treatment of a homogeneous series of patients with a Pouteau Colles fracture are analyzed. Orthopedic treatment provided deceiving results. Pinning was, on the contrary, very effective, intrafocal pinning with immediate mobilization of the wrist appearing perfectly effective. Few complications were reported in contrast to plastered immobilizations. Good results were obtained in 80% of cases and functional recovery was rapid, indicating that this method represents undoubted progress when compared with conventional therapies.  相似文献   
997.
Angiogenesis and patency of blood vessels were analyzed qualitatively in solid CNS and peripheral tissue syngeneic, allogeneic, and xenogeneic grafts and in individual cell suspension grafts of astrocytes, fibroblasts, PC12, and three additional tumor cell lines placed intracerebrally in adult host mice. Postgrafting survival times were 1 day through 4 weeks. The patency of graft vessels was determined in sections from immersion-fixed tissues incubated to reveal the endogenous peroxidase activity of host red cells trapped within the lumen of blood vessels. Additionally, horseradish peroxidase (HRP) was administered intravenously to live hosts; HRP labels host brain and graft vessels on the luminal surface and reveals the presence or absence of a blood-brain barrier (BBB) within the grafts. The origins of blood vessels supplying solid tissue xenografts were identified immunohistochemically with primary antibodies against host (athymic AKR mice) and donor (fetal Lewis rats) major histocompatibility complex (MHC) class I. Blood vessels supplying solid CNS grafts at 1-7 days post-transplantation were identified ultrastructurally and possessed interendothelial tight junctional complexes; however, they were not perfused with either host blood or blood-borne HRP prior to 8 days. Graft vessels at 10 days were outlined consistently by peroxidase-positive red cells in immersion-fixed material and labeled with blood-borne HRP. These vessels provided a BBB to the circulating HRP and exhibited interendothelial tight junctions. Evidence of angiogenesis within solid anterior pituitary grafts and the variety of cell suspension grafts was obtained prior to 3 days post-transplantation in immersion-fixed preparations; the vessels, with the notable exception of those supplying astrocyte cell suspensions, failed to present a BBB to blood-borne peroxidase. Endothelia in the solid pituitary allografts and the PC12 cell grafts were highly fenestrated and exhibited open interendothelial junctions; those in the tumor and fibroblast cell grafts, for the most part, appeared nonfenestrated, and many possessed open interendothelial junctional complexes. Immunostaining for host and donor MHC class I revealed that donor blood vessels predominate over host vessels in CNS xenografts and supply pituitary xenografts exclusively; in both preparations, donor vessels were not identified within the host CNS. Because cell suspension grafts were derived from endothelia-free preparations grown in culture, blood vessels supplying these grafts were necessarily of host CNS origin and manifested a morphological transformation from a BBB to a non-BBB endothelium. The data suggest that angiogenesis in solid CNS grafts placed into the adult host CNS, compared to similarly placed solid peripheral tissue/cell suspension grafts, is not rapid.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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