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81.
Postoperative nomogram predicting the 10-year probability of prostate cancer recurrence after radical prostatectomy. 总被引:3,自引:0,他引:3
Andrew J Stephenson Peter T Scardino James A Eastham Fernando J Bianco Zohar A Dotan Christopher J DiBlasio Alwyn Reuther Eric A Klein Michael W Kattan 《Journal of clinical oncology》2005,23(28):7005-7012
PURPOSE: A postoperative nomogram for prostate cancer recurrence after radical prostatectomy (RP) has been independently validated as accurate and discriminating. We have updated the nomogram by extending the predictions to 10 years after RP and have enabled the nomogram predictions to be adjusted for the disease-free interval that a patient has maintained after RP. METHODS: Cox regression analysis was used to model the clinical information for 1,881 patients who underwent RP for clinically-localized prostate cancer by two high-volume surgeons. The model was externally validated separately on two independent cohorts of 1,782 patients and 1,357 patients, respectively. Disease progression was defined as a rising prostate-specific antigen (PSA) level, clinical progression, radiotherapy more than 12 months postoperatively, or initiation of systemic therapy. RESULTS: The 10-year progression-free probability for the modeling set was 79% (95% CI, 75% to 82%). Significant variables in the multivariable model included PSA (P = .002), primary (P < .0001) and secondary Gleason grade (P = .0006), extracapsular extension (P < .0001), positive surgical margins (P = .028), seminal vesicle invasion (P < .0001), lymph node involvement (P = .030), treatment year (P = .008), and adjuvant radiotherapy (P = .046). The concordance index of the nomogram when applied to the independent validation sets was 0.81 and 0.79. CONCLUSION: We have developed and validated as a robust predictive model an enhanced postoperative nomogram for prostate cancer recurrence after RP. Unique to predictive models, the nomogram predictions can be adjusted for the disease-free interval that a patient has achieved after RP. 相似文献
82.
Andrew Cooper Amit Joglekar Neill Adhikari 《Canadian Medical Association journal》2003,169(8):785-787
83.
Scalp electrical recording during paralysis: quantitative evidence that EEG frequencies above 20 Hz are contaminated by EMG. 总被引:2,自引:0,他引:2
Emma M Whitham Kenneth J Pope Sean P Fitzgibbon Trent Lewis C Richard Clark Stephen Loveless Marita Broberg Angus Wallace Dylan DeLosAngeles Peter Lillie Andrew Hardy Rik Fronsko Alyson Pulbrook John O Willoughby 《Clinical neurophysiology》2007,118(8):1877-1888
OBJECTIVE: To identify the possible contribution of electromyogram (EMG) to scalp electroencephalogram (EEG) rhythms at rest and induced or evoked by cognitive tasks. METHODS: Scalp EEG recordings were made on two subjects in presence and absence of complete neuromuscular blockade, sparing the dominant arm. The subjects undertook cognitive tasks in both states to allow direct comparison of electrical recordings. RESULTS: EEG rhythms in the paralysed state differed significantly compared with the unparalysed state, with 10- to 200-fold differences in the power of frequencies above 20 Hz during paralysis. CONCLUSIONS: Most of the scalp EEG recording above 20 Hz is of EMG origin. Previous studies measuring gamma EEG need to be re-evaluated. SIGNIFICANCE: This has a significant impact on measurements of gamma rhythms from the scalp EEG in unparalysed humans. It is to be hoped that signal separation methods will be able to rectify this situation. 相似文献
84.
Andrew F Shorr William L Jackson Brendan M Weiss Lisa K Moores 《Blood coagulation & fibrinolysis》2007,18(4):309-316
Multiple options exist for the prevention of deep vein thrombosis (DVT) in medical inpatients. We sought to determine the cost-effectiveness of low-molecular-weight heparin (LMWH) relative to unfractionated heparin (UFH) for DVT prevention in this setting. We conducted a cost-effectiveness analysis from the perspective of a third-party payer employing a decision model and literature-based estimates for inputs. In the base-case analysis, LMWH had little impact on the rate of DVT. Despite higher acquisition costs, however, LMWHs resulted in net savings. Routine use of LMWH saves approximately US$89 per patient. The lower rate of heparin-induced thrombocytopenia (HIT) with LMWH accounted for this differential. Univariate sensitivity analysis revealed the model was moderately sensitive to the odds ratio of HIT with LMWH and the cost of HIT. Multivariate sensitivity analysis confirmed the LMWH approach dominated financially. 'Worst-case' scenario modeling, where LMWH actually increased the risk for DVT, had little effect on the rate of HIT, and was substantially more costly than UFH, still demonstrated that LMWHs were economically superior. Monte-Carlo simulation indicated the 95% confidence interval around the estimate for savings with LMWH ranged from US$7 to US$373. We conclude that, despite their higher cost, LMWHs for thromboprophylaxis in medical patients result in savings. 相似文献
85.
Osteochondral Fracture of the Fourth Metatarsal Head Treated by Open Reduction and Internal Fixation
Praveen K.R. Mereddy MBBS MSOrth DNB Orth MRCSEd Andrew Molloy MBchB MRCS FRCS Michael S. Hennessy BSc MBchB FRCSEd 《The Journal of foot and ankle surgery》2007,46(4):320-322
Fracture of the metatarsal head is uncommon, and reports of isolated osteochondral fracture of the metatarsal head are rare. Because of the distal location of the fracture, it is difficult to achieve and maintain reduction, and potential complications include avascular necrosis and subchondral fatigue fracture. The authors present a case of an osteochondral fracture in a 40-year-old man, which was treated by open reduction and internal fixation with a single twist-off screw, with good results 12 months postoperatively. 相似文献
86.
Clinical trial data and fracture risk prediction models unequivocally demonstrate the utility of identifying prevalent vertebral fractures to predict future fractures of all types. Knowledge of prevalent vertebral fractures can alter patient management decisions and result in initiation of therapy to reduce fracture risk in some patients who would not otherwise be treated. Cost-benefit analysis demonstrates that identifying and treating patients with vertebral fractures, even those with a densitometric classification of osteopenia, is cost effective. Vertebral fractures can be readily identified in the office setting using standard radiography or Vertebral Fracture Assessment (VFA), a software addition to a central dual-energy X-ray absorptiometry (DXA) machine. In the United States, VFA was assigned a Current Procedural Terminology (CPT) code in January 2005. Nevertheless, coverage of VFA has not been uniformly embraced by Medicare carriers, companies that contract with the federal government to administer Medicare coverage and process claims for a region of the United States. Unlike DXA, for which uniform national coverage of qualified Medicare beneficiaries is mandated by the Balanced Budget Act of 1997, VFA coverage policies are determined by the local Medicare carriers. Third-party insurers are also variable in their coverage of VFA. This International Society for Clinical Densitometry (ISCD) White Paper documents the role of VFA in the evaluation and treatment of women with postmenopausal osteoporosis and compares it with standard spine radiography. Arguments used by some Medicare carriers and insurers to deny coverage of VFA in the United States are analyzed and critiqued. For health care providers within the United States, this White Paper may serve as a resource to respond to insurers who deny coverage of VFA. For health care providers regardless of their country, this article underscores the value of VFA as an alternative to spine radiography in the evaluation and management of postmenopausal women with suspected osteoporosis. 相似文献
87.
88.
Benjamin Clapp Melba Jarmillo Valeria Vigil Luis Macias Marcia Bouton Cuatemoc Gallardo Andrew Kassir 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2007,11(2):242-245
BACKGROUND AND OBJECTIVES: The purpose of this study was to determine patient recall and comprehension after laparoscopic appendectomy in an underserved population. Laparoscopic surgery can lead to diagnostic uncertainty secondary to poor recall and variable port placement. METHODS: After institutional review board approval, we identified a cohort of patients who underwent laparoscopic appendectomy from 2000 to 2004 at a single institution. We then attempted to contact the patients to conduct a 10-question telephone survey, which determined whether the patient spoke English or Spanish as a primary language, ethnicity, educational level, and questions about recall of perioperative events and diagnoses. If we could not reach the patient, we tried to call back on 2 different occasions. RESULTS: Between 2000 and 2004, 186 patients underwent laparoscopic appendectomy. Of these, 65% were Hispanic. We found that only 17% of these patients returned for a postoperative visit. Only 19.3% could be contacted by phone. Forty-seven percent of the patients contacted by phone spoke Spanish exclusively. Overall 92% of patients contacted knew what operation they had, and gave their correct diagnosis. CONCLUSIONS: The low percentage of patients available to follow-up makes this study statistically insignificant. However, we believe that fact in itself is important. In Southwestern states, we see a large migrant population. This highlights the need to communicate effectively with the patients at the time of surgery, which we speculate we did based on the percentage of patients that knew their diagnosis. 相似文献
89.
John Walls Dr Nick Pidgeon Andrew Weyman Tom Horlick-Jones 《Health, risk & society》2004,6(2):133-150
The binary opposition of trusting or not trusting is inadequate to understand the often ambiguous and contradictory ideas people possess about risk regulators, particularly when knowledge and experience of such institutions is limited. The paper reports qualitative and quantitative data from a major study of public perceptions (n?=?30 focus groups) of UK risk regulators. We compare the complex and widely different ‘trust profiles’ of two regulatory organisations which are institutionally related (the Health and Safety Executive and the Railways Inspectorate) but very separate in the minds of our participants. The paper develops the notion of critical trust to interrogate the various ways in which people make sense of such organisations, as well as discussing the modes of reasoning that people deploy. The paper argues that views of participants are the outcome of a reconciliation of diverse perceptions concerning the role of the organisation, structural factors and the nature of the regulated risk. 相似文献
90.
Use of the deoxyuridine suppression test to evaluate localized folate deficiency in rat colonic epithelium 总被引:1,自引:0,他引:1
M L Cravo J B Mason J Selhub I H Rosenberg 《The American journal of clinical nutrition》1991,53(6):1450-1454
In this study the deoxyuridine suppression test (dUST) was performed on isolated rat colonocytes to establish its value as an indicator of folate status in the colonic epithelium. [3H]thymidine incorporation into DNA was suppressed greater than 90% by deoxyuridine (dU) concentrations greater than 2.5 mumol/L. Preincubation of cells with 5-fluorouracil (1-100 mumol/L) but not methotrexate (10-100 mumol/L) resulted in a significant decrease in the degree of suppression. The dUST performed on colonocytes from folate-deficient animals displayed less suppression than on colonocytes from folate-replete animals (P less than 0.05). The abnormal degree of suppression was corrected by adding 100 mumol folinic acid/L. There was a negative correlation between the degree of suppression and the folate concentration of the colonic epithelium (P less than 0.001). These data indicate that the dUST is useful for detecting folate deficiency in the colonic epithelium and may therefore be valuable in assessing a deficiency state localized to that epithelium. 相似文献