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Localized osteolysis in stable, non-septic total hip replacement   总被引:6,自引:0,他引:6  
We are reporting four cases of extensive, localized bone resorption adjacent to a rigidly anchored, cemented total hip replacement. None of these hips showed evidence of infection on clinical, bacteriological, or pathological evaluation. The tissue from the regions of osteolysis showed sheets of macrophages and foreign-body giant cells invading the femoral cortices. Abundant methylmethacrylate particulate debris was present in the tissues, but polyethylene wear debris was absent. The histological appearance of this tissue resembled that reported about loosened total hip implants with the exception of the synovial-like layer at the cement surface. The cases reported here show that aggressive bone lysis may occur around stable cemented total hip arthroplasties without the presence of sepsis or malignant disease.  相似文献   
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de Vries Reilingh  TS  van Geldere  D  Langenhorst  BLAM  de Jong  D  van der Wilt  GJ  van Goor  H  Bleichrodt  RP 《Hernia》2004,8(1):56-59
Polypropylene mesh is widely used for the reconstruction of incisional hernias that cannot be closed primarily. Several techniques have been advocated to implant the mesh. The objective of this study was to evaluate, retrospectively, early and late results of three different techniques, onlay, inlay, and underlay. The records of 53 consecutive patients with a large midline incisional hernia — 25 women and 28 men, mean age 60.4 (range 28–94) — were reviewed. Polypropylene mesh was implanted using the onlay technique in 13 patients, inlay in 23 patients, and underlay in 17 patients. Either the greater omentum or a polyglactin mesh was interponated between the mesh and the viscera. The records of these 53 patients were reviewed with respect to: size and cause of the hernia, pre- and postoperative mortality and morbidity, with special attention to wound complications. Patients were invited to attend the outpatient clinic at least 12 months after implantation of the mesh for physical examination of the abdominal wall. Postoperative complications occurred in 14 (26.4%) patients. The onlay technique had significantly more complications, as compared to both other techniques. Reherniation occurred in 15 (28.3%) patients. The reherniation rate of the inlay technique was significantly higher than after the underlay technique (44% vs 12%, P=0.03) and tended to be higher than the onlay technique (44% vs 23%, P=0.22). Repair of large midline incisional hernias with the use of a polypropylene mesh carries a high risk of complications and has a high reherniation rate. The underlay technique seems to be the better technique.  相似文献   
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BACKGROUND: The mechanism of progression of established renal disease remains unclear. While a low protein diet slows this progression, the role of cytokines in this process has been little investigated. METHODS: We investigated cytokine expression by Northern blot and immunohistochemistry in two groups of 5/6 nephrectomized rats (5/6 Nx) fed a normal (24%) or low (6%) protein diet and compared them with sham operated controls. RESULTS: The rats on 6% protein diet had significantly less focal glomerulosclerosis (FGS) (17.4 +/- 4.4 vs 27.4 +/- 8.8%, P < 0.05) and global sclerosis (GGS) after 7 weeks (0.4 +/- 0.8 vs 3.5 +/- 2.1% of glomeruli P < 0.05). Both experimental groups showed three times control levels of MCP-I expression after 2 weeks. However in the 5/6 Nx 6% protein group the expression decreased at 4 weeks (1.5 times controls) and reached control levels after 7 weeks. In contrast, the 5/6 Nx 24% protein group exhibited a further marked increase after 4 weeks (5.6 times controls) and was still two-fold higher after 7 weeks. TGF-beta expression was modestly but consistently increased at all time points (120-160% of controls), with no difference between the two study groups. Neither IL-1 beta or TNF-alpha was detectable at any time. Immunohistochemistry demonstrated TGF-beta intracellularly in distal tubular cells in both experimental and control animals, while MCP-1 protein was found in the area of FGS and in the apical pole of distal tubular cells in both experimental groups. Glomerular and interstitial ED1 positive cells were significantly increased after four weeks in the 5/6 Nx 24% protein group (P < 0.05). CONCLUSIONS: A 'mechanical' injury to the kidney clearly results in an inflammatory response associated with the upregulation of MCP-1. A low protein diet modulates the expression of MCP-1 and improves the morphological sequelae seen after renal ablation.   相似文献   
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Olson  MA; Becker  GJ 《Radiology》1986,159(1):25-26
An anomalous pulmonary vein draining into the subdiaphragmatic inferior vena cava was initially demonstrated on computed tomographic (CT) scans. The diagnosis of scimitar syndrome was confirmed with digital subtraction angiography. In retrospect, the anomalous vein and dextroposition of the heart were shown on chest radiographs.  相似文献   
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BACKGROUND: Systemic vascular resistance (SVR) is an integral therapeutic component of patients with heart failure and shock. We hypothesized that the ratio of the peak mitral regurgitant velocity (MRV) (m/s) to left ventricular outflow time-velocity integral (TVI(LVOT)) (cm) by Doppler would provide a noninvasive correlate of SVR. METHODS: SVR was correlated to MRV/TVI(LVOT) in 33 patients undergoing right heart catheterization. Receiver operating characteristic curves were generated to determine the best-balanced sensitivity and specificity to identify SVR > 14 Wood units (WU) and <10 WU. RESULTS: MRV/TVI(LVOT) correlated well with SVR (r = 0.842, 95% confidence interval 0.7-0.92, P <.001, Y = 0.459 + 49.397*X). By receiver operating characteristics, MRV/TVI(LVOT) > 0.27 had a 70% sensitivity and a 77% specificity to identify SVR > 14 WU. MRV/TVI(LVOT) < 0.2 had a 92% sensitivity and a 88% specificity to identify SVR < 10 WU. CONCLUSION: Doppler echocardiography provides a reliable noninvasive assessment of SVR.  相似文献   
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