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排序方式: 共有3299条查询结果,搜索用时 15 毫秒
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Localized osteolysis in stable, non-septic total hip replacement 总被引:6,自引:0,他引:6
M J Jasty W E Floyd A L Schiller S R Goldring W H Harris 《The Journal of bone and joint surgery. American volume》1986,68(6):912-919
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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Adverse reaction to intravenous gadoteridol 总被引:1,自引:0,他引:1
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Focal glomerulosclerosis in the remnant kidney model--an inflammatory disease mediated by cytokines 总被引:7,自引:0,他引:7
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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Amr E Abbas F David Fortuin Bhavesh Patel Carlos A Moreno Nelson B Schiller Steven J Lester 《Journal of the American Society of Echocardiography》2004,17(8):834-838
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