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111.
Mangel L Julow J Major T Hável J Lövey J Viola A Somogyi A Németh G 《Orvosi hetilap》2003,144(5):223-229
INTRODUCTION: The practice of image-based three dimensional treatment planning and conformal radiotherapy techniques give the opportunity to elaborate optimal treatment forms for primary brain tumours. PURPOSE: The authors examined the effect of two novel dose escalation methods on glioblastoma patients. METHODS: In nine cases they treated T1 tumours with single HDR-AL boost of 10-12 Gy dose following the conventional fractionated 60 Gy external beam radiotherapy. In fifteen patients with T2-4 tumours an intensified, hypofractionated regimen with 2.25-2.5 Gy daily and 60 Gy total dose was applied. All the treatments were carried out with image-based conformal methods. RESULTS: Majority of patients endured treatments without neurological deterioration. Transient neurotoxiticy was noticed in one and two cases, respectively. The median survival times (MST) were found to be 17 months (range: 9-25) and 12 months (range: 6-38) in the two groups, respectively. With respect to all patients, the MST was 13 months, while this value in the conventional treatment is generally considered to be 9-10 months. All the three patients who survived more than 18 months was treated with temozolamide chemotherapy as well. CONCLUSION: Based on own experience and current knowledge of authors, it seems reasonable to apply higher biological dose focal radiotherapy and chemotherapy in case of glioblastoma patients with better prognosis. To define the optimal treatment regimens randomised clinical trials should be executed. 相似文献
112.
Major KM Hui T Wilson MT Gaon MD Shabot MM Margulies DR 《American journal of surgery》2003,186(6):615-9; discussion 619
BACKGROUND: Early tracheostomy has been shown to be beneficial after trauma; however, there are few objective data to identify early in the recovery period which patients will ultimately require tracheostomy after blunt head trauma. METHODS: The charts of all patients admitted to the surgical intensive care unit intubated at a level 1 urban trauma center, over a 5-year period with a primary admission diagnosis of blunt head trauma were retrospectively reviewed. RESULTS: Sixty-four patients met inclusion and exclusion criteria and were divided into two groups: those extubated and those that required tracheostomy. By day 3 the Glasgow Coma Scores for the two groups were significantly different and on day 4 the Simplified Acute Physiology (SAPS) Scores were significantly different. CONCLUSIONS: Calculating objective scores such as GCS and SAPS can aid in identifying those patients who will ultimately require a tracheostomy for prolonged airway protection after blunt head trauma with high positive predictive value. 相似文献
113.
114.
Major LF Turner MG 《Journal of healthcare management / American College of Healthcare Executives》2003,48(5):323-33; discussion 334-5
Behavioral health agencies will soon implement automated information-management systems to support their administrative, financial, and clinical care functions. Assessing current information-management capabilities and delineating future needs are prerequisite to recommending a specific information technology solution. Quantifying the discrepancy between current information-management capabilities and future requirements highlights the areas of greatest unmet need for information management. Selecting an information system that addresses the most critical areas of unmet need is a prudent purchase decision. This article describes the results of a process to assess the information-management requirements for agencies that were considering implementation of an integrated behavioral health information-management system. The assessment revealed that these agencies already employed automated systems to manage most financial functions and many administrative functions. Few agencies, however, utilized automated systems to manage clinical care functions. Selection of a behavioral health electronic medical record (EMR) effectively addressed clinical care information-management needs without duplicating existing financial and administrative management functions. Also, the EMR included features that addressed some administrative functions for which a discrepancy between current capabilities and future needs was found. Selecting an EMR instead of an integrated behavioral health information system was associated with a significant reduction in information system acquisition costs. 相似文献
115.
History dependence of rate covariation between neurons during persistent activity in an oculomotor integrator 总被引:2,自引:2,他引:0
Aksay E Major G Goldman MS Baker R Seung HS Tank DW 《Cerebral cortex (New York, N.Y. : 1991)》2003,13(11):1173-1184
Persistent firing in response to a brief stimulus is a neural correlate of short-term memory in a variety of systems. In the oculomotor neural integrator, persistent firing that encodes eye position is maintained in response to transient saccadic eye-velocity commands. To a first approximation, firing rates in the integrator vary linearly with eye position. Thus, viewed across many cells, the pattern of persistent firing in the integrator may be constrained to a unique line of stable states. Here this idea was tested by examining the relationship between firing rates of simultaneously recorded neurons. Paired recordings were obtained in awake goldfish from neurons in hindbrain area I, an essential part of the horizontal eye-position integrator. During spontaneous eye movements consisting of sequential fixations at different horizontal positions, the pair relationship between the majority of cells on the same side of the integrator was not unique: for a given rate of one cell, the rate of the paired cell assumed different values that depended systematically on the preceding saccade history. This finding suggests that the set of persistent firing states that encode eye position is not constrained to a unique line, and that models with stable states restricted to a such a line need to be modified accordingly. 相似文献
116.
Lymphangiomas are rare benign lymphatic tumours found predominantly in the head and neck region. A case of a cavernous lymphangioma isolated to the sphenoid sinus is described. The authors emphasize the extreme rarity of the isolated sphenoid lymphangioma, as to their knowledge this is the first report in the English literature. 相似文献
117.
Calzavara L Burchell AN Remis RS Major C Corey P Myers T Millson M Wallace E 《American journal of epidemiology》2003,157(3):210-217
The objective of this analysis was to identify risk factors for recent human immunodeficiency virus (HIV) infection among homosexual and bisexual men in Ontario, Canada, during 1998-2001. Participants were recruited through the provincial HIV diagnostic laboratory and through physicians and community organizations. HIV test results were used to identify recent seroconverters (cases). A subsample of 183 men (62 cases and 121 controls) enrolled in the Polaris HIV Seroconversion Study as of June 2001 was analyzed. This analysis focused on sexual behaviors with partners who were HIV-positive or whose HIV status was unknown. In multiple logistic regression, independent risk factors were identified. Rates of unprotected receptive oral, insertive anal, and receptive anal sex and delayed application of condoms during receptive anal sex (RAS) were significantly higher among cases (97%, 41%, 53%, and 32%, respectively) than among controls (73%, 19%, 14%, and 2%). Independent risk factors for HIV infection were RAS without condoms (odds ratio = 4.4, p = 0.0004) and delayed application of condoms during RAS (odds ratio = 5.8, p = 0.01). There was an association with condom failure (breakage or slippage) during RAS that approached significance (odds ratio = 2.9, p = 0.09). Delayed application of condoms for RAS may result in contact with preejaculatory fluid. This behavior, which to date has received little attention, may pose as much risk for HIV infection as fully unprotected RAS. 相似文献
118.
BACKGROUND: Patients with cancer metastatic to bone experience several adverse and clinically important skeletal-related events, including pathologic fractures, vertebral compressions with fracture, the need for surgery to treat or prevent fractures, and the need for radiation therapy for the treatment of bone pain. We present appropriate methods for describing and modeling the clinical course of skeletal-related events and comparing treatments for such events. METHODS: On the basis of data from a recently completed randomized, placebo-controlled trial involving 380 breast cancer patients with bone metastases, we tested the validity of the "events-per-person-years" method, one of the most commonly used techniques, for the analysis of skeletal-related events. We then used more robust methods of analysis that are based on fewer assumptions, including a random-effects Poisson model, and contrasted the inferences about skeletal-related event rates and treatment effects for the different analytic methods. All statistical tests were two-sided. RESULTS: The events-per-person-years analysis underestimated substantially the variation in the data and is not appropriate to summarize the incidence rate of skeletal-related events. A random-effects Poisson model did provide a valid basis for analyzing such data. CONCLUSIONS: The underestimation of variability in data associated with the use of the events-per-person-years analysis leads to unduly narrow confidence intervals for complication rates and inflated false-positive error rates in treatment comparisons. A random-effects Poisson model provides a valid, robust basis for describing the clinical course of bone complications and evaluating treatment effects. 相似文献
119.
Promising early outcomes with a novel, complete steroid avoidance immunosuppression protocol in pediatric renal transplantation 总被引:20,自引:0,他引:20
Sarwal MM Yorgin PD Alexander S Millan MT Belson A Belanger N Granucci L Major C Costaglio C Sanchez J Orlandi P Salvatierra O 《Transplantation》2001,72(1):13-21
BACKGROUND: Corticosteroids have been a cornerstone of immunosuppression for four decades despite their adverse side effects. Past attempts at steroid withdrawal in pediatric renal transplantation have had little success. This study tests the hypothesis that a complete steroid-free immunosuppressive protocol avoids steroid dependency for suppression of the immune response with its accompanying risk of acute rejection on steroid withdrawal. METHODS: An open labeled prospective study of complete steroid avoidance immunosuppressive protocol was undertaken in 10 unsensitized pediatric recipients (ages 5-21 years; mean 14.4 years) of first renal allografts. Steroids were substituted with extended daclizumab use, in combination with tacrolimus and mycophenolate mofetil. Protocol biopsies were performed in the steroid-free group at 0, 1, 3, 6, and 12 months posttransplantation. Clinical outcomes were compared to a steroid-based group of 37 matched historical controls. RESULTS: Graft and patient survival was 100% in both groups. Clinical acute rejection was absent in the steroid-free group at a mean follow-up time of 9 months (range 3-13.7 months). Protocol biopsies in the steroid-free group (includes 10 patients at 3 months, 7 at 6 months, and 4 at 12 months) revealed only two instances of mild (Banff 1A) subclinical rejection (reversed by only a nominal increase in immunosuppression) and no chronic rejection. At 6 months the steroid-free group had no hypertension requiring treatment (P=0.003), no hypercholesterolemia (P=0.007), and essentially no body disfigurement (P=0.0001). Serum creatinines, Schwartz GFR, and mean delta height Z scores trended better in the steroid-free group. In the steroid-free group, one patient had cytomegalovirus disease at 1 month and three had easily treated herpes simplex stomatitis, but with no significant increase in bacterial infections or rehospitalizations over the steroid-based group. The steroid-free group was more anemic early posttransplantation (P=0.004), suggesting an early role of steroids in erythrogenesis; erythropoietin use normalized hematocrits by 6 months. CONCLUSIONS: Complete steroid-free immunosuppression is efficacious and safe in this selected group of children with no early clinical acute rejection episodes. This protocol avoids the morbid side effects of steroids without increasing infection, and may play a future critical role in avoiding noncompliance, although optimizing renal function and growth. 相似文献
120.
OBJECTIVE: To determine the pattern and severity of maxillofacial injuries sustained in a motor vehicle accident (MVA) resulting from automobile restraint use. DESIGN: Retrospective database review of patients injured in a MVA who were admitted to the level I trauma center at the University of Louisville Hospital in Louisville, Kentucky. METHODS: Demographic data, drug and alcohol impairment screening, and comorbidity data were obtained from database searches of trauma records. Forty-four patients had an airbag deployed, 34 patients wore seat belts, and 94 patients were unrestrained. All maxillofacial Abbreviated Injury Scale (AIS) ratings were compared among the three groups. RESULTS: Twenty-two of the 44 patients (50%) in the airbag group sustained only facial injuries. Fifteen of them had lacerations; four others had only facial abrasions. Three of the airbag patients had moderate facial injuries (AIS = 2); none required operative management. The airbag group had a mean AIS rating of 1.13, the seat belt group a mean AIS of 1.29, and the unrestrained group a mean AIS of 1.46. Patients using either seat belts (mean age, 40.5 y) or airbags (mean age, 44.9 y) were older than the unrestrained group (mean age, 39.6 y). Drug and/or alcohol impairment was significantly greater in the unrestrained group (mean, 38%) compared with the seat belt group (mean, 26%) and the airbag group (mean 11%.). CONCLUSIONS: Use of airbags is associated with less severe maxillofacial injuries compared with either a seat belt alone or no restraint. There is an inherent risk of minor maxillofacial injuries with airbag usage, but the severity of injury is distinctly reduced. 相似文献