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71.
M Jasty W J Maloney C R Bragdon D O O'Connor T Haire W H Harris 《The Journal of bone and joint surgery. British volume》1991,73(4):551-558
We studied 16 femora retrieved at post-mortem from symptomless patients who had a satisfactory cemented total hip arthroplasty from two weeks to 17 years earlier, with the aim of delineating the initial mechanisms involved in loosening. Only one specimen showed radiographic evidence of loosening; the other 15 were stable to mechanical testing at 17.0 Nm of torque. In all 16 specimens, the cement-bone interface was intact with little fibrous tissue formation. By contrast, separation at the cement-prosthesis interface and fractures in the cement mantle were frequent. The most common early feature was debonding of the cement from the metal, seen at the proximal and distal ends of the prosthesis. Specimens which had been in place for longer also showed circumferential fractures in the cement, near the cement-metal interface, and radial fractures extending from this interface into the cement and sometimes to the bony interface. The most extensive cement fractures appeared to have started at or near sharp corners in the metal, or where the cement mantle was thin or incomplete. Fractures were also related to voids in the cement. The time relationship in this series suggested that long-term failure of the fixation of cemented femoral components was primarily mechanical, starting with debonding at the interface between the cement and the prosthesis, and continuing as slowly developing fractures in the cement mantle. 相似文献
72.
Fleischer AC; Dudley BS; Entman SS; Baxter JW; Kalemeris GC; James AE Jr 《Radiology》1987,162(2):307-310
The depth of myometrial invasion by endometrial carcinoma was evaluated using real-time sonography (US) in 20 patients with histologically proved adenocarcinoma of the endometrium. In 14 of 20 (70%) cases, US-based estimation of the depth of myometrial invasion was within 10% of the actual measurement in the gross specimen. The US-based estimation of tumor invasion was low in seven patients, high in four patients, and agreed with pathologic findings (+/- 5%) in nine patients. In four patients with polypoid intraluminal extension of tumor, a deeply invasive tumor was suspected on US but was not found on pathologic examination. In 12 superficially invasive tumors, the continuity of the demarcating subendometrial halo was intact in nine and incomplete in three. In six patients with deeply invasive tumors, this zone was partially disrupted in four, totally disrupted in one, and intact in one. Errors of estimation of the depth of myometrial invasion on US most frequently occurred when a tumor had a significant intraluminal polypoid extension. Demonstration of a subendometrial halo usually indicated superficial invasion, whereas the absence of a halo was frequently associated with deep invasion. 相似文献
73.
Breast and axillary tissue MR imaging: correlation of signal intensities and relaxation times with pathologic findings 总被引:1,自引:0,他引:1
We tested a variety of inversion-recovery (IR) and spin-echo (SE) sequences by imaging the breast masses of 22 patients before surgery and 23 tissue specimens with magnetic resonance (MR) imaging at 0.6 T to determine the most effective pulse sequences to evaluate breast disease. An SE pulse sequence using a long repetition time (TR) of 1,600 msec and a long echo time (TE) of 90 msec was found to be the most sensitive in depicting carcinoma in the excised tissue specimens, with all of the carcinomas (n = 15) demonstrating irregular areas of higher signal intensity (SI) than that of the adjacent fat. However, only five of 11 breast carcinomas present in the preoperative patients produced a higher SI than that produced by fat on the same T2-weighted sequence. Five of the remaining six carcinomas in the preoperative patients appeared as localized distortions of fibroductular architecture on both T2-weighted SE and IR sequences. In axillary tissue specimens, both metastatic carcinoma and hyperplastic lymph nodes produced a high SI on T2-weighted SE sequences. However, metastatic carcinoma had a significantly longer T2 relaxation time than did hyperplastic lymph nodes. 相似文献
74.
A prospective study screening for visual impairment in a day centre for people with a mental handicap showed that 30% required spectacles or registration as blind or partially-sighted and a further 20% had previously unknown pathology. Carers were not reliable in identifying visual problems in their charges, and routine screening should be encouraged. High Street optometrists should be able to measure visual acuity in the individuals in this sample excluding those cared for in special care units for whom screening may be less beneficial. 相似文献
75.
D M Smith M J Ness J D Landmark W W Haire A Kessinger 《Journal of clinical apheresis》1990,5(2):70-73
Leukapheresis recently has been used to harvest circulating hematopoietic stem cells for autologous transplantation. This technique is especially useful when involvement of the bone marrow by tumor precludes its use as a source for stem cells. Thirty-five patients have had peripheral blood stem cells harvested for transplantation by this technique at our institution. Two patients with adenocarcinoma of the breast developed severe headaches during apheresis, and both were found to have extensive intracranial metastases. For one patient, the pain was excruciating and associated with hypotension at the end of each collection phase of the apheresis procedure and resolved approximately 5 minutes after reinfusion of the patient's red cells and plasma. Subsequently this patient had a documented subdural hydroma. Following an apheresis procedure, while receiving local low dose thrombolytic therapy for thrombosis of the brachiocephalic vein, she suffered a fatal intracerebral hemorrhage. The second patient had a severe exacerbation of a headache of recent onset. Leukapheresis was abandoned when extensive intracranial disease was documented. We conclude that recurrent neurologic symptoms, especially cranial pain, during the withdrawal phase of intermittent flow apheresis may predict intracranial pathology in patients. Peripheral stem cell apheresis and lymphocytapheresis are bringing patients with metastatic malignancies to the apheresis department with increasing frequency, and the apheresis staff must be alert to previously undescribed complications of apheresis. 相似文献
76.
AC Davaine A Saraux S Prigent I Kupfer‐Bessaguet D Roswag P Plantin P Schoenlaub F Talarmin A Zagnoli L Misery 《Journal of the European Academy of Dermatology and Venereology》2008,22(12):1471-1477
Background Anti‐tumour necrosis factors (anti‐TNF) are more and more used, but the rate of skin adverse events is not known. Objective The aim was to assess the number of skin infections and other dermatoses in patients treated with anti‐TNFα. Patients and methods One hundred eighty‐seven patients suffering from rheumatoid arthritis or ankylosing spondylitis underwent a dermatological exam. Patients with anti‐TNF were compared with those without this treatment in a prospective transversal study. Results Among them, 59 patients were treated with anti‐TNFα and steroids were prescribed in 100 cases. There was no difference in the prevalence of skin infections or eczema or tumours. Skin drug reactions were observed in six patients. Infections by dermatophytes appear very frequent, approaching 70% in both groups. Conclusions This study shows that skin infections (or other skin diseases) are not more frequent in these patients. No differences were observed in infections (bacterial fungal, parasital or viral), tumours, psoriasis or the manifestations of atopic dermatitis. Nonetheless, a long‐term survey might be interesting, especially about skin tumours. 相似文献
77.
Obstructed central venous catheters. Restoring function with a 12-hour infusion of low-dose urokinase 总被引:1,自引:0,他引:1
Thrombotic obstruction frequently prohibits infusion through or withdrawal of blood from central venous catheters and can occur in conjunction with symptomatic thrombosis of the subclavian vein. Thirty catheters were radiographically proved to be obstructed by thrombus and had not responded to at least one instillation of 5000 units of urokinase. All catheters were treated with a 12-hour infusion of urokinase at the rate of 40,000 units/hour. The obstructing thrombus was either eliminated or reduced in size in all instances and full function was restored in all but one catheter. No bleeding complications were seen. Six patients with obstructed catheters also had symptoms of subclavian vein thrombosis. All patients with symptoms of subclavian vein obstruction became asymptomatic on anticoagulant therapy even though no attempt at dissolving the thrombus obstructing the subclavian vein was made. A 12-hour infusion of low doses of urokinase can safely salvage function of obstructed catheters that otherwise may require replacement. Patients with concomitant subclavian vein thrombosis become asymptomatic on anticoagulant therapy without need to dissolve the obstructing thrombus. 相似文献
78.
79.
80.
Femoral capital osteonecrosis: MR finding of diffuse marrow abnormalities without focal lesions 总被引:13,自引:0,他引:13
Six painful hips in five patients were examined with magnetic resonance (MR) imaging and were found to have diffuse signal abnormalities in the marrow of the femoral head and neck, which extended into the intertrochanteric area in five cases. The abnormal regions were low in signal intensity on images obtained with a short repetition time (TR) and a short echo time (TE) and were isointense or hyperintense on long TR/TE images--findings that have been attributed by others to bone marrow edema. Edema was also seen in marrow just above the acetabulum in two cases. No focal abnormalities characteristic of osteonecrosis were seen. Osteonecrosis was subsequently shown to be present in all six femoral heads at core biopsy (three cases) or by subsequent development of focal MR abnormalities reported to be highly specific for osteonecrosis (three cases). The affected hips had been radiographically normal or subtly osteopenic and had shown intense radionuclide uptake in the femoral head at scintigraphy, with lesser abnormality in the neck and intertrochanteric region. Follow-up MR examinations of five of the six femoral heads showed the diffuse abnormalities to have been transient. Although diffuse MR abnormalities in the proximal femur are not specific, they may indicate the presence of osteonecrosis of the femoral head. 相似文献