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81.
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83.
A number of risk factors based upon mostly retrospective surgical data, have been formulated in order to identify impending pathological fractures of the femur from low-risk metastases. We have followed up patients taking part in a randomised trial of radiotherapy, prospectively, in order to determine if these factors were effective in predicting fractures. In 102 patients with 110 femoral lesions, 14 fractures occurred during follow-up. The risk factors studied were increasing pain, the size of the lesion, radiographic appearance, localisation, transverse/axial/circumferential involvement of the cortex and the scoring system of Mirels. Only axial cortical involvement >30 mm (p = 0.01), and circumferential cortical involvement >50% (p = 0.03) were predictive of fracture. Mirels' scoring system was insufficiently specific to predict a fracture (p = 0.36). Our results indicate that most conventional risk factors overestimate the actual occurrence of pathological fractures of the femur. The risk factor of axial cortical involvement provides a simple, objective tool in order to decide which treatment is appropriate.  相似文献   
84.
Intratumoral injection of a radiocolloid for lymphatic mapping enables the therapeutic excision of clinically occult breast cancer with the aid of a gamma-ray detection probe. The aim of this study was to determine the success rate of radio-guided tumour excision in addition to a guide wire and to identify factors predicting clear margins. Sixty-five consecutive patients underwent radio-guided tumour excision after intratumoral injection of 99mTc-nanocolloid guided by ultrasound or stereotaxis. A localization wire was inserted after scintigraphy had been performed (group 1). The results were compared with retrospective data from 67 consecutive patients who underwent therapeutic wire-directed excision alone (group 2). Factors predicting clear margins (> or = 1 mm) were determined in a logistic regression model. Adequate margins were obtained in 83% of group 1 and in 64% of group 2 (P = 0.014). The invasive component was incompletely excised in two patients in group 1 and in 14 patients in group 2. Further surgery was performed in four patients in group 1 and in 14 patients in group 2. Factors predictive of clear margins were decreasing pathological tumour diameter (P = 0.035), increasing weight of the specimen (P = 0.046), absence of microcalcifications (P = 0.004) and absence of carcinoma in situ component (P = 0.024). Radio-guided excision was an independent predictor of complete excision of the invasive component (P = 0.012). The application of radio-guided surgery combined with wire localization seems to improve the outcome of therapeutic excision of non-palpable invasive breast cancer compared with wire-directed excision alone.  相似文献   
85.
Objective: To develop a preliminary classification system for errors in otolaryngology. Methods: A retrospective, anonymous survey was distributed to 2,500 members of the American Academy of Otolaryngology–Head and Neck Surgery (AAO‐HNS). Respondents were asked whether an error had occurred in their practice in the last 6 months, and if so, to describe the error, its consequences, and any corrective action taken. Results: There were 466 (18.6%) responses. Two hundred ten (45% of respondents) otolaryngologists reported 216 errors. A classification system for errors in otolaryngology was developed. Errors were classified as related to history and physical (1.4%), differential or final diagnosis (1.4%), testing (10.4%), surgical planning (9.9%), wrong‐site surgery (6.1%), anesthesia‐related (3.3%), wrong drug/dilution on the surgical field (3.8%), technical (19.3%), retained foreign body (0.9%), equipment‐related (9.4%), postoperative care (8.5%), medical management (13.7%), nursing/ancillary (0.5%), administrative (6.6%), communication (3.8%), and miscellaneous (0.9%). There were 78 cases of major morbidity and 9 deaths. If these data are representative, there may be more than 2,600 episodes of major morbidity and more than 165 deaths related to medical error in otolaryngology patients annually. Conclusions: Human error in otolaryngology occurs in all practice components, including diagnostic, treatment, surgical, communication, and administrative. Types of errors reported by otolaryngologists differ from those reported by other specialists. Error classification systems may need to reflect each specialty's realm of practice. Errors in otolaryngology cause appreciable morbidity and mortality. Quantitative study of errors and the development of targeted prevention and amelioration strategies should be a high priority.  相似文献   
86.
BACKGROUND: The mucopolysaccharidosis (MPS) are a group of inherited metabolic disorders resulting from the deficiency of the enzyme responsible for intralysosomal catabolism of glycosaminoglycans (GAGs). GAGs are progressively accumulated in multiple tissues and released into the corporal fluids. The first laboratory approximation to MPS diagnosis is the identification of an increased urinary GAG excretion. For this, several semiquantitative and quantitative methods have been developed. The aim of this retrospective statistical study was to evaluate the reliability of MPS urine screening for the semiquantitative Berry spot test (BST) and the quantitative dimethylmethylene blue test (DMB). METHODS: The 24-h-urine samples (n = 246) were tested through BST, DMB, and for GAG excretion pattern by one-dimensional electrophoresis or thin layer chromatography. RESULTS: the 204 samples that demonstrated a normal GAG excretion pattern were considered as non-MPS samples. Forty-two samples presented an abnormal GAG excretion pattern. Enzyme analysis was available for 31 out of 42 patients (31/42), confirming that all were affected by MPS. Urinary GAG concentrations of MPS patients by DMB were increased 1.04- to 7.1-folds, compared to age-related normal levels. The sensitivity was 100% for DMB and 93.6% for BST. DMB demonstrated a specificity of 74.5%, while BST a specificity of 53.9%. The specificity of MPS screening increased to 84.3%, considering conjunctly DMB and BST. CONCLUSION: The DMB is a sensitive method, however, inclusion of BST could increase the specificity of MPS urine screening.  相似文献   
87.
OBJECTIVE: To determine the absorption, excretion and metabolism of kaempferol in humans. DESIGN: A pharmacokinetic study of kaempferol from endive over 24 h. SUBJECTS: Four healthy males and four healthy females. RESULTS: Kaempferol, from a relatively low dose (9 mg), was absorbed from endive with a mean maximum plasma concentration of 0.1 microM, at a time of 5.8 h, indicating absorption from the distal section of the small intestine and/or the colon. Although a 7.5-fold interindividual variation between the highest and lowest maximum plasma concentration was observed, most individuals showed remarkably consistent pharmacokinetic profiles. This contrasts with profiles for other flavonoids that are absorbed predominantly from the large intestine (eg rutin). An average of 1.9% of the kaempferol dose was excreted in 24 h. Most subjects also showed an early absorption peak, probably corresponding to kaempferol-3-glucoside, present at a level of 14% in the endive. Kaempferol-3-glucuronide was the major compound detected in plasma and urine. Quercetin was not detected in plasma or urine indicating a lack of phase I hydroxylation of kaempferol. CONCLUSIONS: Kaempferol is absorbed more efficiently than quercetin in humans even at low oral doses. The predominant form in plasma is a 3-glucuronide conjugate, and interindividual variation in absorption and excretion is low, suggesting that urinary kaempferol could be used as a biomarker for exposure.  相似文献   
88.
One of the most avidly debated issues in lymphatic mapping is where the tracers are best deposited in patients with breast cancer. The four superficial approaches are easy to perform and have several other distinct advantages. They are based on the hypothesis that the entire breast parenchyma and the overlying skin drain to a common node in the axilla because of their common embryological origin. Evidence is presented that casts doubt upon the correctness of this assumption. Tracer administration close to the tumor site appears to be the safest approach for the time being. Excellent results can be obtained with this latter approach, despite the fact that it is technically more demanding.  相似文献   
89.
Technology assessment of saline contrast hysterosonography   总被引:6,自引:0,他引:6  
OBJECTIVE: The purpose of our study was to evaluate to which extent saline contrast hysterosonography (SCHS) is able to replace diagnostic hysteroscopy in uterine cavity evaluation in women suspected of intrauterine abnormalities. STUDY DESIGN: In this prospective observational study we performed SCHS instead of diagnostic hysteroscopy. Diagnostic hysteroscopy was performed in case of failed or inconclusive SCHS. Univariate and multivariate analyses were used to assess subgroups for their risk of failure and inconclusiveness. RESULTS: Two hundred fourteen women were included consecutively. SCHS was conclusive in 180 cases (84.1%), failed in 12 (5.6%), and inconclusive in 22 (10.3%). Uterine size above 600 cm(3) was the best predictor of failure and/or inconclusiveness (positive predictive value 0.42). CONCLUSION: SCHS was able to replace 84% of the outpatient diagnostic hysteroscopies in uterine cavity evaluation in women suspected of intrauterine abnormalities. Our study showed that diagnostic hysteroscopy can be restricted to inconclusive or failed SCHS.  相似文献   
90.
We describe the survival at ten years of 100 femoral components of the Freeman hip prosthesis. It is proximally hydroxyapatite (HA)-coated and was fixed without cement. Radiological assessment identified radiolucent lines (RLLs) and lytic lesions and was used to measure migration. The criterion of failure was revision or impending revision for aseptic femoral loosening. No femoral components were revised or are awaiting revision for aseptic loosening, giving 100% survival at ten years (95% confidence interval, 95.7 to 100), although 59 were at risk at ten years. Two components were revised for fracture of a ceramic head with damage to the trunnion. Although well fixed in each, for survival analysis we evaluated the hip as if the patient had died. Twelve acetabular components were revised and at each operation the femoral component was found to be well fixed, was not disturbed and remained in the survival analysis. Three patients were lost to follow-up, and 12 died with well-functioning prostheses. Radiologically, all except one of the components appeared to be well fixed with no RLLs and no lytic lesions at the latest follow-up. The mean vertical migration was 0.4 mm at one year, 0.8 mm at two years and 1.4 mm at ten years. One component had migrated 7.6 mm at ten years (2.1 mm in year 1) and developed RLLs in Gruen zones I and II. The symptoms, however, were only minor and revision was not indicated. Our study has shown that proximal HA coating gives effective fixation for a femoral component.  相似文献   
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