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171.
One hundred thirty consecutive patients with metastatic spinal cord compression (MSCC) were entered in a therapeutic protocol in which radiation therapy (RT) played the main role. When MSCC is diagnosed by clinical-radiologic methods such as myelography with or without computed tomography (CT) or magnetic resonance imaging (MRI), steroids are given and RT treatment started within 24 hours. When diagnostic doubts exist or stabilization is necessary, surgery precedes RT. Chemohormonal potentially responsive tumors are also treated with chemotherapy or hormonal therapy. Twelve patients (9.2%) underwent surgery plus RT, and 118 (90.8%) received RT alone. Thirteen (11%) early death patients were not evaluable. The 105 evaluable cases that received RT alone were analyzed. Median follow-up was 15 months (range, 4 to 38 months). Response among patients with back pain was 80%. In cases with motor dysfunction, 48.6% improved, and in 33 of 105 patients (31.4%) without motor disability there was no deterioration. Forty percent of patients with autonomic dysfunction responded to RT. Median survival time was 7 months with a 36% probability of survival for 1 year. The median duration of improvement was 8 months. The most important prognostic factor was early diagnosis. Radiosensitivity of tumor was only important in paraparetic patients in predicting response to RT. Complete myelographic block significantly diminished response to RT. Vertebral collapse did not influence response or survival.  相似文献   
172.
The technical aspects of IMRT applied to cervix cancer are discussed in this paper, as well as issues related to tumor delineation, target volume definitions, inverse planning, and IMRT delivery. A theoretical example illustrating how IMRT can accurately mimic dose distributions obtained using conventional planning plus HDR brachytherapy is also shown. The notion of clinical optimization parameters is introduced to account for the radiation delivery variables, which affect the overall treatment time. This is especially relevant to the possible introduction of intrafractional movement and resulting inaccuracy, as well as facility efficiency.  相似文献   
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176.
Terminal deoxynucleotidyl transferase and repertoire development   总被引:11,自引:0,他引:11  
Summary: In mice, the absence of terminal deoxynucleotidyl transferase (Tdt) expression during fetal and neonatal life provides a window in development where clones of lymphocytes are generated that provide protective immunity. Introducing premature Tdt activity interferes with the development of these clones and results in an impaired ability to make protective antibodies. Conversely, gene-targeted disruption of Tdt prevents N additions at all stages of T and B-lymphocyte development and promotes the development of fetal-like T and B-cell clones into adulthood, with accompanying alterations in repertoire. The alternative splice forms of Tdt may be necessary to provide regulatory mechanisms to restrict N addition to appropriate stages of the developmental pathways, the details of which are being revealed. The evidence continues to build that Tdt is a key player in influencing the outcome of V(D)J recombination during lymphocyte and repertoire development.  相似文献   
177.
Metastatic Spinal Cord Compression (MSCC), an oncologic emergency, is a frequent complication of many neoplastic diseases in an advanced stage. Our experience is reported, which was obtained with a series of 61 patients following a diagnostic-therapeutic protocol aimed at early diagnosing MSCC and at assigning the major role in therapy to radiotherapy (RT) alone. Fifty-seven patients with an average follow-up of 13 months (range 4-26) were evaluable. Diagnosis was always made by means of myelography and/or myelography plus CT. In 50 cases the treatment consisted in RT alone and the remaining 7 patients had surgery before RT because of diagnostic doubts; in 1 case the patient was operated on because stabilization was necessary. A dose of 30 Gy was delivered, over 2 weeks, (TDF = 62) to those tumors which were considered as radiation-responsive and having a better prognosis (myeloma, lymphoma), whereas all the other histologies were given a split-course regimen (5 Gy x 3 days, stop x 4 days, +/- 3 Gy x 5 days; TDF = 68). All patients received medium or high doses of steroid depending on the degree of neurologic involvement. Patients with chemo/hormone-responsive primary tumors also received chemotherapy and/or hormone therapy. The clinical parameters considered in evaluating the response to treatment were backache, motor performance, and sphincter function. Respectively 86%, 47% and 44% of patients responded. Early diagnosis was the most important prognostic factor, whereas histology of the primary tumor was important in cases with severe neurologic damage only. The results obtained are similar to those reported in literature and confirm the value of the diagnostic-therapeutic approach used, which suggests continuing this trial.  相似文献   
178.

Background

A greater emphasis on providing high-value orthopaedic interventions has resulted in increased health economic reporting. The contingent-valuation method (CVM) is used to determine consumer valuation of the benefits provided by healthcare interventions. CVM is an important value-based health economic tool that is underutilized in orthopaedic surgery.

Questions/Purposes

The purpose of this study was to (1) identify previously published CVM studies in the orthopaedic literature, (2) assess the methodologies used for CVM research, and (3) understand how CVM has been used in the orthopaedic cost–benefit analysis framework.

Methods

A systematic review of the literature using the MEDLINE database was performed to compile CVM studies. Search terms incorporated the phrase willingness to pay (WTP) or willingness to accept (WTA) in combination with orthopaedic clinical key terms. Study methodology was appraised using previously defined empirical and conceptual criteria for CVM studies.

Results

Of the 160 studies retrieved, 22 (13.8%) met our inclusion criteria. The economics of joint arthroplasty (n?=?6, 27.3%) and non-operative osteoarthritis care (n?=?4, 18.2%) were the most common topics. Most studies used CVM for pricing and/or demand forecasting (n?=?16, 72.7%); very few studies used CVM for program evaluation (n?=?6). WTP was used in all included studies, and one study used both WTP and WTA. Otherwise, there was little consistency among included studies in terms of CVM methodology. Open-ended questioning was used by only ten studies (45.5%), a significant number of studies did not perform a sensitivity analysis (n?=?9, 40.9%), and none of the studies accounted for the risk preference of subjects. Only two of the included studies applied CVM within a cost–benefit analysis framework.

Conclusion

CVM is not commonly reported in orthopaedic surgery and is seldom used in the context of cost–benefit analysis. There is wide variability in the methods used to perform CVM. We propose that CVM is an appropriate and underappreciated method for understanding the value of orthopaedic interventions. Increased attention should be paid to consumer valuations for orthopaedic interventions.
  相似文献   
179.

Background:

The quality and state of satisfaction reporting after total knee replacement (TKR) is variable.

Questions/Purposes:

The purposes of this systematic review were (1) to examine the available literature on patient satisfaction after TKR, (2) to evaluate the quality of available evidence, and (3) to identify predictors of patient satisfaction after TKR.

Methods:

A systematic review of the MEDLINE database was performed. The initial search yielded 1219 studies. The inclusion criteria were English language, clinical outcome study with primary outcome related to TKR for osteoarthritis, and patient-reported satisfaction included as an outcome measure. Studies were assessed for demographics, methodology for reporting satisfaction, and factors influencing satisfaction.

Results:

Two hundred eight studies, including 95,560 patients who had undergone TKR, met all inclusion and exclusion criteria; 112 (53.8%) of these studies were published in the past 3 years. Satisfaction was most commonly measured using an ordinal scale. Twenty-seven studies (13%) used a validated satisfaction survey. Eighty-three percent of studies reported more than 80% satisfaction. The most commonly reported predictor of satisfaction was post-operative patient-reported functional outcome. Pre-operative anxiety/depression was the most common pre-operative predictor of dissatisfaction.

Conclusion:

There are numerous studies reporting patient satisfaction after TKR, and publication on the topic has been increasing over the past decade. However, the majority of studies represent lower levels of evidence and use heterogeneous methods for measuring satisfaction, and few studies use validated satisfaction instruments. In general, the majority of studies report satisfaction rates ranging from 80 to 100%, with post-operative functional outcome and relief of pain being paramount determinants for achieving satisfaction.
  相似文献   
180.
The primary goal of this study was to investigate associations between regional gray matter (GM) atrophy and neuropsychological function in multiple sclerosis (MS), while accounting for the influence of central brain atrophy (i.e. third ventricle enlargement). Using a cross-sectional design, we studied 59 MS patients with brain MRI and neuropsychological testing. Regional gray matter fractions (rGMFs) were calculated from MRI images for 11 homologous brain areas using the semiautomatic brain region extraction (SABRE) technique. Neuropsychological testing followed consensus panel guidelines and included tests emphasizing episodic memory, working memory and processing speed. The analytic approach was stepwise linear regression, with forward selection and p<0.05 threshold for significance. Consistent with previous research, there were significant correlations between third ventricle width and neuropsychological tests. Stepwise linear regression analyses controlling for third ventricle width retained rGMFs obtained from specific regions within the prefrontal cortex. Left frontal atrophy was associated with tests emphasizing auditory/verbal memory. Right frontal atrophy was associated with impairment in visual episodic and working memory. For the first time, we show an independent relationship between cortical atrophy and cognitive impairment after accounting for the effects of central atrophy.  相似文献   
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