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1.
Paul Hochstein Ulrich Glatzel Thomas Schmickal Andreas Wentzensen 《Trauma und Berufskrankheit》2002,4(2):s110-s114
The treatment of deep cartilage defects in load-bearing joints is a problem that still has no satisfactory solution. Full-thickness defects of the articular cartilage rarely heal spontaneously, usually leaving damage that can lead to early arthrosis. Techniques currently available for the treatment of chondral defects include abrasion, drilling, micro-fracturing, transplantation of tissue autografts and allografts, and cell transplantation. Osteochondral autograft transplantation is currently the only surgical cartilage repair technique known to lead to the formation of genuine hyaline articular cartilage and its retention at least in the medium term. The Draenert method, in which a water-cooled diamond bone-cutting system is used, is an effective procedure for resurfacing the joints affected by localised cartilaginous defects, even when there is also severe bone loss. Donor-side morbidity can be kept to a minimum by filling the defect caused by harvesting with a press-fit cylinder of cancellous bone covered with periosteum for protection. 相似文献
2.
The role of a doctor appointed to advise an employers’ liability insurance association can only develop from the tasks entrusted to him or her by the administrative offices. In the past, these related mainly to providing help in formal administratative procedures. Questions on how treatment should proceed and active involvement in this complex were not considered the province of doctors retained in an advisory capacity except to a limited degree and in most cases in a rather late phase. For the past few years, many insurance associations have been redefining their tasks relating to treatment. New concepts, the introduction of guidelines, staff training, and the active inclusion of medical knowledge to influence administrative decisions in concrete individual situations have meant new groups of tasks for the consulting doctor. The employers’ liability insurance associations are increasingly in need of access to medical knowledge, and especially at short notice, resulting in an enhanced need for medical advice and spatial and temporal integration of medical work in the individual administrative offices. It is no longer realistic to have access to medical expertise only after office hours or when file is submitted. 相似文献
3.
Hochstein Paul Heppert Volkmar Grtzner Paul Alfred Matschke Stefan Wentzensen Andreas 《Trauma und Berufskrankheit》2003,5(1):s56-s61
Malunion and nonunion after fracture present many difficulties in trauma surgery. Selection of the best therapy and operative techique requires careful analysis of the complications. Hyperthrophic nonunion of the femur shaft is mostly best treated with locking reamed nails. Significant differences in torsions after nailing can be corrected by repositioning of the distal interlocking screws if recognized sufficiently early. After fracture healing an open rotation osteotomy is necessary; stabilization can be achieved by means of medullary nails or a condylar plate. How a malalignment of the bone axis is corrected depends on the position of a malunion, the functional deficit caused, and the biomechanical demands on the joint. Condylar plates can often solve the problems in this region. There are also guidelines for ¶the treatment of atrophic and infected nonunions (recommended procedures are ¶aggressive debridement, autologous cancellous bone graft, and biological osteosynthesis), but the treatment of individual cases requires a exhaustive knowledge of and experience in this special field. It is quite common for even well-established procedures to fail. When the bone is biologically reduced and this is the reason for malunion newly developed techniques of internal fixation can be applied. The less invasive stabilization system (LISS), combined with autologous cancellous bone grafting if necessary, can result in healing even in a worst-case scenario. 相似文献
4.
以18-甲基-17β-羟基-17α-乙炔基-雌甾-4-烯-3-酮(18-甲基炔诺酮),17β-羟基-17α-乙缺基-雌甾-4-烯-3-酮(炔诺酮),17β-羟基-17α-乙炔基-雄甾-4-烯-3-酮(妊娠素)和17a-羟基孕甾-4-烯-3,20二酮(17α-羟基黄体酮)为原料,经NaBH,还原、脱水、双键转位和酯化等反应合成一系列3,5-甾二烯化合物,用1HNMR和MS证明了它们的结构。动物筛选结果表明,17β-丙酰氧基-17α-乙炔基-雌甾-3,5-二烯(IVb2有明显的抗早孕活性。中断早期妊娠的作用似与其雌激素活性有关。 相似文献
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Physical and biological properties of U.S. standard endotoxin EC after exposure to ionizing radiation. 下载免费PDF全文
Techniques that reduce the toxicity of bacterial endotoxins are useful for studying the relationship between structure and biological activity. We used ionizing radiation to detoxify a highly refined endotoxin preparation. U.S. standard endotoxin EC. Dose-dependent changes occurred by exposure to 60Co-radiation in the physical properties and biological activities of the endotoxin. Sodium dodecyl sulfate-polyacrylamide slab gel electrophoresis showed gradual loss of the polysaccharide components (O-side chain and R-core) from the endotoxin molecules. In contrast, although endotoxin revealed a complex absorption pattern in the UV range, radiation treatment failed to modify that pattern. Dose-related destruction of the primary toxic component, lipid A, was suggested by the results of activity tests: both the pyrogenicity and limulus reactivity of the endotoxin were destroyed by increasing doses of radiation. The results indicate that the detoxification is probably due to multiple effects of the ionizing radiation on bacterial lipopolysaccharides, and the action involves (i) the destruction of polysaccharide moieties and possibly (ii) the alteration of lipid A component of the endotoxin molecule. 相似文献
9.
Lipopolysaccharide (LPS) from Brucella abortus is less toxic than that from Escherichia coli, suggesting the possible use of B. abortus or LPS from B. abortus as a carrier in vaccines. 下载免费PDF全文
J Goldstein T Hoffman C Frasch E F Lizzio P R Beining D Hochstein Y L Lee R D Angus B Golding 《Infection and immunity》1992,60(4):1385-1389
Brucella abortus may be useful as a component of vaccines. This is because it possesses several unique properties as a carrier that enable it to stimulate human B cells even in the relative absence of T cells. Human immunodeficiency virus type 1 proteins conjugated to B. abortus could induce neutralizing antibodies against human immunodeficiency virus type 1. Recently we showed that the characteristics of lipopolysaccharide (LPS) derived from B. abortus are similar to those of the whole bacterium in that the LPS acts as a T-independent type 1 carrier in mice. In this study we wanted to determine whether LPS derived from B. abortus is associated with the adverse effects seen with other bacterial endotoxins. LPS purified from B. abortus by butanol extraction was shown to have less than 2% (wt/wt) contamination by protein and less than 1% (wt/wt) contamination by nucleic acids and to contain 1% (wt/wt) ketodeoxyoctanic acid. Compared with LPS derived from Escherichia coli, B. abortus LPS was 10,000-fold less potent in eliciting fever in rabbits, 268-fold less potent in killing D-galactosamine-sensitized mice, and 1,400-fold and 400-fold less potent in inducing interleukin-1 beta and tumor necrosis factor alpha production, respectively. These results suggest that B. abortus LPS is much less likely than the LPS from E. coli to evoke endotoxic shock; therefore, it may be feasible to incorporate B. abortus as a component of vaccines. 相似文献
10.
Quantitative antimicrobial susceptibility test for Streptococcus pneumoniae using inoculum supplemented with whole defibrinated sheep blood. 总被引:2,自引:1,他引:2 下载免费PDF全文
R F D'Amato J M Swenson G A McKinley L Hochstein A A Wallman D J Cleri A J Mastellone L Fredericks L Gonzalez D H Pincus et al. 《Journal of clinical microbiology》1987,25(9):1753-1756
The National Committee for Clinical Laboratory Standards recommends the use of lysed horse blood-supplemented Mueller-Hinton broth for determining the quantitative antimicrobial susceptibility of Streptococcus pneumoniae. This procedure may be difficult for laboratories using previously prepared or commercial MIC systems. Therefore, a study was undertaken to determine whether previously prepared microdilution trays containing Mueller-Hinton broth without blood could be used for determining the antimicrobial susceptibility of S. pneumoniae by adding whole defibrinated sheep blood to the bacterial suspension used to inoculate the trays. The presence of alpha-hemolysis was used as an indicator of bacterial growth. One hundred isolates of S. pneumoniae selected to represent a distribution of susceptibility patterns were tested by the National Committee for Clinical Laboratory Standards method and the sheep blood-supplemented-inoculum method. Greater than 94% agreement between the two methods was achieved. The sheep-blood-supplemented-inoculum procedure was highly reproducible and easy to perform and provides an acceptable alternative for determining the MICs for S. pneumoniae for laboratories using previously prepared or commercial microdilution systems. 相似文献