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BACKGROUND: Dye-directed sentinel node biopsy (SNB) for breast cancer provides accurate staging with low morbidity, but for tumors distant from the axilla, its use has been questioned. HYPOTHESIS: Can preoperative breast lymphoscintigraphy (BL) applied selectively to medial hemisphere tumors predict a subset of patients who may not require surgical staging of the axilla? DESIGN: Prospective cohort study. SETTING: Tertiary, multidisciplinary breast center. PATIENTS: Thirty-two women with breast tumors located in the medial hemisphere (30) or inframammary crease (2). INTERVENTION: Peritumoral injection of 500 microCi of technetium Tc 99m sulfur colloid and biplanar imaging. Nonpalpable lesions were localized with ultrasound or mammography. At the time of definitive breast surgery, isosulfan blue dye-directed SNB was performed. Axillary dissection was performed when the SN contained a tumor or could not be identified. MAIN OUTCOME MEASURES: Regional nodal basins identified by BL; success rate of SNB. RESULTS: Preoperative BL demonstrated axillary drainage in 28 patients (88%); 2 patients (6%) had isolated internal mammary radionuclide uptake, and 2 patients had no nodal uptake. Dye-directed axillary SNB succeeded in 27 (87%) of 31 patients, including both patients with failed BL. Breast lymphoscintigraphy had predicted isolated internal mammary drainage in 2 of 4 patients whose SNs could not be identified. Metastases were found in 5 patients (16%). CONCLUSIONS: Axillary radionuclide uptake predicts but does not augment dye-directed SN identification. In those few patients with isolated internal mammary drainage, BL may obviate the need for surgical staging of the axilla.  相似文献   
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The aim of this study was to develop a placebo model for bipolar disorder to help optimize clinical trial designs for studies targeting manic episodes in bipolar disorder. A bipolar disease database was built based on individual longitudinal data collected from over 3,000 patients in 11 clinical trials for 5 approved bipolar drugs. An empirical placebo effect model with an exponential decay process plus a linear progression process was developed to quantify the time course of the Young Mania Rating Scale total score based on only placebo data from the database. In order to describe the dropout pattern during the trials, a parametric survival model was developed and the Weibull distribution was identified to be the best distribution to describe the data. Based on the likelihood ratio test, it was found that patients with higher baseline score, slower disease improvement and more rapid disease progression tended to dropout earlier, and the trial features such as trial starting year and trial site were also significant covariates for dropout. A combination of the placebo effect model and the dropout model was applied to simulate new clinical trials through Monte-Carlo simulation. Both the placebo effect model and dropout model described the observed data reasonably well based on various diagnostic plots. The joint placebo response and dropout models can serve as a tool to simulate the most likely level of placebo response with the expected dropout pattern to help design a new clinical trial.  相似文献   
5.
The risks of thromboembolism following operative treatment of ankle fractures are deep vein thrombosis (DVT) and pulmonary embolism (PE). These are potentially life-threatening complications. Many orthopedic surgeons fail to appreciate the potential complications of thromboembolic events because of their rare and delayed occurrence in foot and ankle operations. The purpose of this report is to describe the potential for DVT and PE following ankle operations. We present three cases in which patients who underwent operative treatment of ankle fractures subsequently developed PE. We also review the literature on the prevalence of thrombosis, risk factors, methods of prophylaxis, and use of prophylaxis in surgical procedures of the lower extremity.  相似文献   
6.
Pediatric heart allocation in Eurotransplant (ET) has evolved over the past decades to better serve patients and improve utilization. Pediatric heart transplants (HT) account for 6% of the annual transplant volume in ET. Death rates on the pediatric heart transplant waiting list have decreased over the years, from 25% in 1997 to 18% in 2011. Within the first year after listing, 32% of all infants (<12 months), 20% of all children aged 1–10 years, and 15% of all children aged 11–15 years died without having received a heart transplant. Survival after transplantation improved over the years, and in almost a decade, the 1‐year survival went from 83% to 89%, and the 3‐year rates increased from 81% to 85%. Improved medical management of heart failure patients and the availability of mechanical support for children have significantly improved the prospects for children on the heart transplant waiting list.  相似文献   
7.

Background

Severe cerebral venous-sinus thrombosis (CVT) is a rare disease, and its clinical course, imaging correlates, as well as long-term prognosis have not yet been investigated systematically.

Methods

Multicenter retrospective study. Inclusion criteria were CVT, Glasgow coma scale ≤9, and treatment in the intensive care unit. Primary outcome was death or dependency, assessed by a modified Rankin Score (mRS) >2 at last follow-up.

Results

114 patients were included. At last follow-up (median 2.5 years), 38 patients (33.3 %) showed no or minor residual symptoms (mRS = 0 or 1), 12 (10.5 %) had a mild (mRS = 2), 13 (11.4 %) a moderate (mRS = 3), 12 (10.5 %) a severe disability (mRS = 4 or 5), and 39 (34.2 %) had died. In bivariate analysis, predictors of poor outcome were any signs of mass effect on imaging, clinical deterioration after admission, and age. In contrast, clinical symptoms on admission and parenchymal lesions per se, such as edema, infarction, or hemorrhage were not predictive. Multivariate predictors of poor outcome were an increase in National Institutes of Health Stroke Scale ≥3 after admission [odds ratio (OR) 6.7], bilateral motor signs in the further course (OR 9.2), and midline shift (OR 5.1).

Conclusion

The outcome of severe CVT is almost equally divided between severe impairment or death and survival with no or only mild handicap. Specifically, space-occupying mass effect and associated neurologic deterioration seem to determine a poor outcome. Therefore, early detection and treatment of mass effect should be the focus of critical care.
  相似文献   
8.

Background

Physiological tibiofemoral kinematics have been shown to be important for good knee function after total knee arthroplasty (TKA). The purpose of the present study was to investigate the influence of component rotation on tibiofemoral kinematics during knee flexion. We asked which axial component alignment best reconstructs physiological tibiofemoral kinematics and which combinations should be avoided.

Methods

Ten healthy cadaveric knees were examined. By means of a navigational device, tibiofemoral kinematics between 0° and 90° of flexion were assessed before and after TKA using the following different rotational component alignment: femoral components: ligament balanced, 6° internal, 3° external rotation, and 6° external rotation in relation to the posterior condylar line; tibial components: self-adapted, 6° internal rotation, and 6° external rotation.

Results

Physiological tibiofemoral kinematics could be partly reconstructed by TKA. Ligament-balanced femoral rotation and 6° femoral external rotation both in combination with 6° tibial component external rotation, and 3° femoral external rotation in combination with 6° tibial component internal rotation or self-aligning tibial component were able to restore tibial longitudinal rotation. Largest kinematical differences were found for the combination femoral component internal and tibial component external rotations.

Conclusion

From a kinematic-based view, surgeons should avoid internal rotation of femoral components. However, even often recommended combinations of rotational component alignment (3° femoral external and tibial external rotation) significantly change tibiofemoral kinematics. Self-aligning tibial components solely restored tibiofemoral kinematics with the combination of 3° femoral component of external rotation. For the future, navigational devices might help to axially align components to restore patient-specific and natural tibiofemoral kinematics.  相似文献   
9.
OBJECTIVE: Standard lung donor criteria have been established on opinions and individual experiences rather than on existing evidence. Since the scarcity of donor organs is one of the major limitations to lung transplantation, extension of donor lung criteria might considerably increase the donor pool. This study therefore evaluates the outcome, achieved with the use of extended donors versus standard donors and aims to redefine lung donor criteria. METHODS: We performed a retrospective analysis of 98 consecutive primary lung transplantations from 94 donors from 1/2001 to 12/2002. Donors were classified as extended if they fulfilled at least one criteria: age >55 years, PaO(2) at FiO(2)/PEEP 5 <300mmHg, tobacco history >20 pack years, inhalative drug abuse, presence of infiltration on chest X-ray or purulent secretions at bronchoscopy. Recipients were stratified in two groups according to whether they received a 'standard' or 'extended' organ. Postoperative complications, extubation time, ICU and hospital stay and survival were compared. RESULTS: Twenty-three (24.5%) donors were extended. Twenty-six recipients (26.55%) received organs from extended donors. Differences in intubation times (12+/-2 days standard vs. 14+/-5 days extended, P=0.70), ICU stay (16+/-2 days standard vs. 18+/-5 days extended, P=0.74) and hospital stay (38+/-4 days standard vs. 40+/-6 days extended, P=0.71) were not statistically significant. Postoperative bleeding rates were comparable (n=14 standard vs. n=3 extended) as well as bronchial anastomotic complications (n=7 standard vs. n=3 extended). Three months survival was 88.89% in the standard group vs. 92.31% in the extended group. One year survival is comparable as well with 81.94 vs. 84.62%, respectively. CONCLUSIONS: The use of lung donors who fail to meet standard criteria does not impair short and medium term results compared to standard lung donors. The impact on long term development of BOS has yet to be evaluated. The strict application of standard lung donor criteria excludes a considerable number of lungs potentially suitable for transplantation, thus liberalisation of donor criteria might help to overcome donor shortage.  相似文献   
10.
BACKGROUND: Physicians teach sun awareness to their patients, but frequently have no formal training in this area. A week-long dermatology curriculum during Sun Awareness Week that included skin cancer and sun awareness education to first-year medical students was introduced in May 1998 at the University of Western Ontario, London, Canada. OBJECTIVE: The purpose of this study was to determine the baseline knowledge, attitudes, and behaviour of the first-year medical students towards sun awareness before and after the new curriculum. METHOD: This study used a pre- and post-test design to determine the impact of the curriculum on the medical students' knowledge, attitudes, and intent to change behaviour. It also reports any influence of demographic variables on these parameters. RESULTS: The students demonstrated a substantial improvement in their knowledge of sun-related topics despite some baseline knowledge. Many students reported unhealthy behaviour prior to the curriculum, but demonstrated an intent to adopt more healthy behaviour after the curriculum. Minor differences in knowledge and behaviour due to demographic characteristics disappeared upon completion of the curriculum. CONCLUSIONS: An undergraduate medical curriculum with skin cancer and sun awareness education can improve the medical students' knowledge, attitudes, and behaviour towards sun awareness.  相似文献   
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