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81.
Effect of low-friction ion-treated femoral heads on polyethylene wear rates   总被引:2,自引:0,他引:2  
Polyethylene wear is a major contributor to osteolysis and subsequent aseptic loosening of prosthetic components in total hip arthroplasty. Use of ion implantation as a surface modification to the metallic bearing component of orthopaedic implants may be an effective means of reducing wear debris at the bearing interface. In July 1991, low friction ion treated femoral heads were introduced. This study evaluates the effect of the low friction ion treated femoral head on polyethylene wear. Fifty-five total hip arthroplasties (53 patients) with low friction ion treated femoral heads followed up a minimum of 3 years were matched with 55 total hip arthroplasties (47 patients) without low friction ion treated femoral heads for the same postoperative period. Socket wear was evaluated radiographically. Case matching and strict inclusion criteria were used to control for known factors influencing polyethylene wear. These criteria included: (1) cases matched for gender and age within 2 years; (2) diagnosis limited to osteoarthritis or avascular necrosis of the femoral head only; (3) femoral head diameter limited to 26 or 28 mm only; (4) hydroxyapatite coated femoral stem of the same design and a metal backed socket of the one of two designs with the same polyethylene insert; and (5) minimum followup of 3 years. The linear wear rate of polyethylene was 0.161 +/- 0.095 mm per year in the group without the low friction ion treated heads and 0.116 +/- 0.101 mm per year in the low friction ion treated group. The volumetric wear rates were 74.5 +/- 44.3 mm3 per year for the group without the low friction ion treated heads and 57.8 +/- 51.1 mm3 per year for the low friction ion treated group. Assuming the sensitivity of these measurements can detect these small differences in wear accurately, these results suggest low friction ion treated prosthetic heads are useful in reducing polyethylene wear at 3-year minimum followup.  相似文献   
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Langerhans cell histocytosis (LCH) and Erdheim‐Chester disease are two rare histiocytic disorders. Their occurrence in the same patient is more infrequent, but has been described. We report a case of a 38‐year‐old woman who presented with a diagnosis of single system cutaneous LCH. Subsequently, she developed multiple papules on her extremities consistent with a non‐LCH xanthogranuloma type lesion. BRAFV600E mutation immunostain, VE1 was positive in the skin lesion, which was confirmed by molecular polymerase chain reaction (PCR) studies, initiating a complete systemic workup for Erdheim‐Chester disease. Systemic involvement was confirmed with bilateral sclerotic bone lesions and retroperitoneal and pelvic fibrosing disease. She was also found to have a BRAFV600E mutation positive papillary thyroid carcinoma. New suspicious cutaneous lesions presenting in patients with a history of LCH need to be biopsied. A BRAFV600E mutation in a non‐LCH histiocytic lesion with a xanthogranuloma phenotype (CD163/CD68/CD14/fascin/Factor 13a) should prompt an Erdheim‐Chester disease workup. This is a unique case of a woman with BRAFV600E mutation positive Erdheim‐Chester disease and cutaneous LCH, while also being, to our knowledge, the first reported case in the English literature of it occurring in a patient with a BRAFV600E mutation positive papillary thyroid carcinoma.  相似文献   
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The regimen for treating refractory angina is similar to that for impending infarction. Specific approaches to treatment include drugs and other medical methods. Operative intervention is reserved for those patients who do not respond to medical measures.  相似文献   
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The neurophysiology of volitional voiding is a poorly understood and constantly evolving field. Some of the most difficult clinical problems in urology arise from structural or neural deviations from this process. These may occur as a result of traumatic injury, congenital defect, or neurological disease. Neurogenic voiding dysfunction is a frequently encountered disorder with multiple etiologies and nonstandardized care. A pervasive complaint in neurogenic voiding dysfunction is detrusor overactivity and resultant urinary incontinence. However, the results of “ideal” initial therapy—catheterization with or without anticholinergics—have been far from satisfactory. This review attempts to go beyond perfunctory measures to explore recent data on anticholinergic therapies, long-term data on botulinum A toxin injections, and applications of neuromodulation.  相似文献   
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Skin lesions are rare in visceral leishmaniasis, especially in Mediterranean countries. We describe an unusual case of visceral leishmaniasis in a 41-year-old man that began with a skin lesion. The parasites isolated from both the skin lesion and the bone marrow were typed as Leishmania donovani sensu stricto. This pathogen is not endemic in Israel or neighboring countries; its contribution to adult visceral leishmaniasis in Israel is summarized.  相似文献   
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A factor that augmented the phagocytosis of IgG-coated ox red blood cells by the human monocyte/macrophage line U937 was identified in cell culture supernatants from two of two patients with angiocentric peripheral T cell lymphomas, three of three patients with angiocentric immunoproliferative lesions that were not frankly malignant, and one of two patients with T lymphoblastic malignancies. The factor was not present in supernatants derived from 14 nonangiocentric peripheral T cell lymphomas of other histologic types nor in ten cases of B cell lymphoma and two cases of Hodgkin's disease. A similar factor was present in the supernatants of concanavalin A (Con A)-stimulated normal peripheral blood mononuclear cells and in the supernatants of IL-2- dependent T cell lines derived from normal peripheral blood. The factor had an apparent mol wt of greater than 50,000 daltons, was heat labile (100 degrees C for two minutes), and stable at pH 2.0. Its stimulation of phagocytosis was independent of any increase in number of Fc receptors. Thus, this factor is probably not gamma-interferon. This factor may play a pathogenetic role in the hemophagocytic syndromes associated with certain T cell malignancies and immunodeficient states.  相似文献   
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Sixteen female smokers participated in a study of ‘safer cigarettes’ and bought their cigarettes from the experimenters at less than prevailing prices. Half received an economic incentive for purchasing cigarettes delivering progressively less tar and nicotine: the other half paid the same price regardless of brand purchased. Subjects were not required to change brands. Twelve of the sixteen subjects completed the twelve-week study. Significant reductions in tar and nicotine intake, which persisted for more than six months beyond the twelve-week study period, occurred in both groups. The differences between the two groups in tar and nicotine intake were not significant. A control group of seven female smokers showed little change in tar and nicotine intake over the same twelve-week period, and only modest changes in the subsequent six months. Neither the number of cigarettes smoked nor exhaled carbon monoxide levels (measured in a subsample of participants) increased as the subjects switched to lower nicotine levels.  相似文献   
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