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排序方式: 共有2374条查询结果,搜索用时 15 毫秒
1.
2.
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
3.
4.
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
5.
Ralls PW; Johnson MB; Kanel G; Dobalian DM; Colletti PM; Boswell WD Jr; Radin DR; Halls JM 《Radiology》1986,161(2):451-454
FM sonography - a signal-processing technique that uses frequency and phase information as well as amplitude data - shows promise in evaluation of patients with diffuse liver disease. In a prospective blinded review of 37 patients with biopsy-proved liver disease and 42 healthy volunteers, FM sonography was clearly superior to traditional amplitude-based (AM) sonography in distinguishing healthy from diseased subjects. Statistically significant differences were seen in accuracy (FM, 98.7%; AM, 84.8%), sensitivity (FM, 97.3%; AM, 70.3%), and negative predictive value (FM, 97.7%; AM, 78.8%). Our data also suggest that current FM sonographic techniques cannot differentiate among histologic findings associated with different hepatic parenchymal abnormalities. It is unclear, therefore, whether FM imaging can reduce the numbers of patients who require biopsy for diagnosis or the frequency of biopsy procedures in patients with known disease. 相似文献
6.
顾性初 《中国医药工业杂志》1995,(11)
抑制幽门螺杆菌产生的脲酶具有治疗胃炎和消化性溃疡的作用。用酚红指示剂和Berthelot试剂在96孔培养板上检测重组脲酶活性,其灵敏度指标酚红法每mg酶蛋白引起的每分钟吸光度变化。△A为6.9,而Berthelot法每mg酶蛋白引起的每分钟吸光度比值变化△A为313。结果表明用Berthelot试剂检测重组脲酶活性适宜在96孔培养板上大规模筛选天然产物中的脲酶抑制剂。 相似文献
7.
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
8.
Ohne Zusammenfassung 相似文献
9.
Genotype-phenotype correlation for nucleotide substitutions in the IgII- IgIII linker of FGFR2 总被引:6,自引:3,他引:3
10.
Brigitte Schiller Chun He David J. Salant Alice Lim Jessy J. Alexander Richard J. Quigg 《The Journal of experimental medicine》1998,188(7):1353-1358
Crry (complement receptor 1–related protein/gene y) is a key cellular complement regulator in rodents. It is also present in Fx1A, the renal tubular preparation used to immunize rats to induce active Heymann nephritis (HN), a model of membranous nephropathy. We hypothesized that rats immunized with anti-Fx1A develop autoantibodies (auto-Abs) to Crry as well as to the megalin-containing HN antigenic complex, and that anti-Crry Abs promote the development of injury in HN by neutralizing the complement regulatory activity of Crry. Rats immunized with Fx1A lacking Crry remained free of proteinuria and glomerular deposits of C3 during a 10-wk follow-up despite typical granular immunoglobulin (Ig)G deposits in glomeruli. Anti-Fx1A auto-Abs were present in their sera at levels that were not different from sera pooled from proteinuric rats with HN induced with nephritogenic Fx1A. Passive administration of sheep anti-Crry Abs to rats immunized with Crry-deficient Fx1A led to proteinuria and glomerular C3 deposition, which were not seen in such rats injected with preimmune IgG, nor in rats with collagen-induced arthritis injected with anti-Crry IgG. To directly examine the role of Crry in HN, rats were immunized with Crry-deficient Fx1A reconstituted with rCrry. This led to typical HN, with 8 out of 15 rats developing proteinuria within 14 wk. Moreover, the extent of glomerular C3 deposition correlated with proteinuria, and anti-Crry Abs were present in glomerular eluates. Thus, Crry is a key nephritogenic immunogen in Fx1A. Formation of neutralizing auto-Abs to Crry impairs its function, leading to unrestricted complement activation by Abs reactive with the HN antigenic complex on the epithelial cell surface. 相似文献