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61.
Chromium concentrations in serum, blood clot and urine from patients following total hip arthroplasty 总被引:2,自引:0,他引:2
Chromium released from implant alloys may be incorporated into organometallic complexes as Cr3+ [Cr(III)] or CR6+[Cr(VI)]. Since Cr(VI) is far more biologically active than Cr(III), there is considerable interest in identifying the valence state that predominates in corrosion products, either in vitro or in vivo. It is known that erythrocytes display a unidirectional uptake of Cr(VI) while effectively excluding Cr(III). Thus it was felt that a study of the chromium content of blood clot, in comparison to chromium concentrations in serum and urine, could shed light on the valency question. Fourteen patients who received conventional polymethylmethacrylate cemented cobalt-chromium alloy/ultra high molecular weight polyethylene total hip replacements as well as seven control patients who underwent orthopaedic procedures without implantation were studied. Blood and urine specimens were obtained preoperatively, post-operatively and, for total hip patients, at routine early follow up. Chromium content was determined by electrothermal atomic absorption spectroscopy. A significant post-operative rise in serum chromium content was observed for total hip replacement patients, as previously reported, but not for control patients. Unexpected day-to-day variations in clot chromium content, without significant increases, were also observed. Longer time studies are required to determine chromium valence states in corrosion products in this model. 相似文献
62.
Clinical Potential of Digital Linear Tomosynthesis Imaging of Total Joint Arthroplasty 总被引:1,自引:0,他引:1
The present study was performed to evaluate the potential for clinical application of digital linear tomosynthesis in imaging
hip prostheses. Volumetric x-ray digital linear tomosysnthesis was used to image hip prostheses. The tomosynthesis was compared
to metal artifact reduction (MAR) computed tomography (CT), and non-MAR CT scans of a prosthesis case. The effectiveness of
this method in enhancing visibility of a prosthesis case was quantified in terms of the signal-to-noise ratio (SNR), and removal
of ghosting artifacts in a prosthesis case was quantified in terms of the artifact spread function (ASF). In the near in-focus
plane, the contrast is greater in the MAR CT or tomosynthesis relative to the non-MAR CT. The order of ASF performance of
the algorithm was as follows: (1) tomosynthesis; (2) MAR-CT; (3) non-MAR CT. The potential usefulness of digital linear tomosynthesis
for evaluation of hip prostheses was demonstrated. Further studies are required to determine the ability of digital linear
tomosynthesis to quantify the spatial relationships between the metallic components of these devices as well as to identify
bony changes with diagnostic consequences. 相似文献
63.
Toni Wendler Martin Heilemann Ronny Grunert Robert Möbius Michael Schmidt Stefan Schleifenbaum 《Journal of medical engineering & technology》2020,44(2):69-75
AbstractDiscrepancy in leg length does frequently occur as a side effect of total hip arthroplasty and may lead to reduced patient satisfaction as well as injury in the sequalae. It is consequently important to reduce leg length discrepancy where-ever technically possible. This may be achieved by recording precise intraoperative measurements and using different sized implanted components. The aim of the given study was to improve the accuracy of a previously validated optic measurement system (OMS) to reduce leg length discrepancy. This pre-existing OMS was first trialled and based on these preliminary findings developed further. Using this improved system, measurements were taken in models and cadavers. Inter observer reliability of the improved OMS was assessed. The system is introduced in the given technical feasibility study. Its accuracy was greater in the model setup (swivel joint: 772.7?±?1.5?mm; ball joint: 770.0?±?3.7?mm; reference: 772?mm) compared to the trial using cadaveric tissues (588.8?±?5.7?mm; reference: 586?mm). Results of two examiners were similar. The third one measured significantly shorter values (p=.011). The results of the measurements with the OMS indicate that a significant increase in accuracy (p?=?2.076×10?6) has been achieved compared to the previously reported system, however, a further improvement to measurement accuracy is necessary for this to be applied clinically. 相似文献
64.
影响直肠癌全直肠系膜切除术预后因素 总被引:5,自引:1,他引:5
目的:探讨影响直肠癌全直肠系膜切除术预后的主要因素.方法:选取2000年7月至2002年6月间的102例行直肠癌全直肠系膜切除术的病人作为研究对象,回顾性分析病人临床资料.结果:102例行直肠癌全直肠系膜切除术的病例,失访4例,失访率为3.9%,现存活96例,10例术后复发和转移,复发率为10.2%,91例术后性生活无显著障碍,99例泌尿功能基本正常.结果表明影响直肠癌全直肠系膜切除术预后存在因素.结论:直肠癌全直肠系膜切除术可以减少术后复发和转移,减少患者术后泌尿和性功能方面的并发症,可提高病人生活质量的保证. 相似文献
65.
66.
Bedaiwy MA Goldberg JM Falcone T Singh M Nelson D Azab H Wang X Sharma R 《Human reproduction (Oxford, England)》2002,17(3):601-604
BACKGROUND: Oxidative stress mechanisms are involved in the pathophysiology of many reproductive disorders. The objective of this study was to characterize oxidative stress parameters in hydrosalpingeal fluid (HSF) and examine their possible role in early embryo development. METHODS AND RESULTS: HSF was aspirated at laparoscopic salpingectomy in 11 infertile women. Reactive oxygen species (ROS), total (non-enzymatic) antioxidant capacity (TAC) and lipid peroxidation (LPO) were assayed. Two-cell mouse embryos were incubated with 25, 50 or 75% HSF and the blastocyst development rate was observed. ROS was detected in five of 11 (45%) HSF samples with a mean of 4.2 x 10(4) c.p.m. LPO was detected in all samples at a mean (+/- SD) value of 5575.4 +/- 6091.9 micromol/l malonaldehyde. The mean blastocyst development rate at 25, 5+/- 0 and 75% HSF and in the control group was 88.9 +/- 9.4, 65.7 +/- 19.1, 45.7 +/- 5.7 and 96.7% respectively (P < 0.0001). The blastocyst development rate was positively correlated to ROS concentrations (P < 0.02) but was not significantly related to LPO. CONCLUSIONS: The blastocyst development rate decreased with increasing concentrations of HSF. For the first time, the presence of ROS, LPO and TAC activity in human HSF was characterized. A possible role of oxidative stress in the embryotoxicity of HSF is suggested. 相似文献
67.
目的 探讨人工全膝关节置换术后的康复训练方法。方法 回顾分析2001年8月至2005年8月16例(17膝)人工全膝关节置换术后病人康复训练的过程及效果。结果 人工全膝关节置换术后经过系统康复训练,所有膝关节功能评分达到(70-86分)平均80分。结论 人工全膝关节置换手术效果与术后全面系统的康复训练密切相关。 相似文献
68.
V. A. Struchkov N. B. Strazhevskaya D. Yu. Blokhin 《Bulletin of experimental biology and medicine》1992,113(5):716-719
All-Russian Oncologic Scientific Center, Academy of Medical Sciences, Moscow. (Presented by Academician of the Academy of Medical Sciences N. N. Trapeznikov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 113, No. 5, pp. 529–531, May, 1992. 相似文献
69.
It is shown that oxipine (mexidol; a 3-hydroxypyridine-derived antioxidant) injected intravenously into rabbits in a dose
of 10 or 25 mg/kg alleviates the severity of the anaphylactic reaction, lowers the anaphylactic index, and considerably reduces
the percentage of anaphylaxic shock-induced mortality. The preparation causes changes in the ratio of the total lipid to phospholipid
fractions of lymphocytes, which has distinctive features in intact, primed, and challenged animals. It is thought that the
antiallergic effects of oxipine are connected with both inhibition of free-radical oxidation and with the ability of the preparation
to alter receptor properties of the allergy target cells due to its effect on the lipid ensembles of the cell membranes.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, No 4, pp. 384–386, April, 1995
Presented by P. V. Sergeev, Member of the Russian Academy of Medical Sciences 相似文献
70.
Mounir Fouad F Mamer O Khayyal M Sauriol F Lesimple A Ruhenstroth-Bauer G 《Medical hypotheses》2004,63(6):1024-1034
We are elaborating on the kinetics and mechanisms of septic rabbit liver to de novo biosynthesize acute-phase response (APR) proteins under in vitro conditions of deepening ischemia in reference to their in vivo prevalence in serum and cerebrospinal fluids (CSF) collected at predetermined times. The significance of the data is interpreted as relevant to grafting cadaveric liver into end-stage liver diseased patients and APR-induced ischemic heart diseases (IHD). Hepatic APR was induced by CCl(4)-intubation, and the administration of cholera toxin (CT) or scorpion venom (SV), or both, to rabbits. Hepatic functional efficiency, in terms of biosynthesis of APR proteins in closed circuit perfusion of the isolated intoxicated liver with oxygenated saline or L-15 media paralleled the two-dimensional immunoelectrophoresis (2D-IEP) spectrum of APR serum proteins at time of liver isolation. We are suggesting: (a) in vitro biosynthesis of plasma proteins by isolated perfused liver is the result of in vivo decoded and retained APR inflammatory signals; and (b) decoded inflammatory signals are expressed not withstanding the perfusate's organic composition. Furthermore, 90 min of ischemic perfusion in saline or L-15 medium precipitated mitochondrial aberrations which resulted in further deterioration of de novo biosynthesis of APR plasma proteins. Regardless of the nature of the inflammatory stimuli, mitochondrial aberrations rendered the perfused organ a biologically inert tissue mass that was incapable of resuming biological function upon perfusion with oxygenated L-15 medium. This is most likely due to ischemia-induced irreversible hepatic necrosis. Thus, in vitro aberrations of mitochondrial function(s) critically limit the capability of the isolated liver to resume its organic function to sustain biosynthesis of de novo plasma proteins. Extrapolation of these results to the surgical management of end-stage liver diseases points to the importance of the status and the handling protocol(s) of the cadaver donor liver prior to successful grafting. We conclude that although histology of a cadaver liver may reveal well-preserved hepatic cellular organelles with at least minimal intra- and intercellular communication required for viable hepatic function, we deem it essential to further define acceptable minimal capabilities to de novo biosynthesize plasma proteins by a cadaver liver as a measure of its functional viability and suitability for transplantation. Ultimately, this measure may improve the success of liver transplants with minimal surgical and drug interventions. 相似文献