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81.
Paulino AC Wen BC Buatti JM Hussey DH Zhen WK Mayr NA Menezes AH 《American journal of clinical oncology》2002,25(2):117-122
From 1965 to 1997, 49 patients were diagnosed and treated for intracranial ependymoma at one institution. Tumor location was infratentorial in two thirds, and pathology was low grade in 38 patients (78%). Gross total resection of the primary tumor was achieved in 21 (43%). Thirty-six patients received adjuvant radiotherapy; the entire neuraxis was treated in 14, whole brain in 10, and local field only in 12. Median follow-up was 9.6 years (range, 2-33 years). The 5-, 10-, and 15-year overall survival rates were 71.4%, 63.5%, and 63.5% for craniospinal radiotherapy, 60.0%, 60.0%, and 40.0% for whole brain radiotherapy, and 80.8%, 64.6%, and 64.6% for local field radiotherapy (p = 0.88). The 5-, 10-, and 15-year local control rates were 60.3%, 54.4%, and 48.9%. The prognostic factors for a better local control rate were gross total resection (p = 0.021) and low grade histology (p = 0.031). Seventeen of 43 (39.5%) M0 patients did not respond to treatment; all had local failure and 4 also had a spinal relapse. Spinal relapse developed in 3 of 31 (10%) M0 patients who did not receive spinal radiotherapy, whereas 1 of 12 (8%) who had spinal radiotherapy did not respond to treatment in the spine. The results of this study indicate that local radiotherapy is sufficient for M0 patients with intracranial ependymoma. 相似文献
82.
Curative radiotherapy for primary orbital lymphoma 总被引:8,自引:0,他引:8
Bhatia S Paulino AC Buatti JM Mayr NA Wen BC 《International journal of radiation oncology, biology, physics》2002,54(3):818-823
PURPOSE: To review our institutional experience with primary orbital lymphoma and determine the prognostic factors for survival, local control, and distant metastases. In addition, we also analyzed the risk factors for complications in the radiotherapeutic management of this tumor. METHODS AND MATERIALS: Between 1973 and 1998, 47 patients (29 women [62%] and 18 men [38%], median age 69 years, range 32-89) with Stage IAE orbital lymphoma were treated with curative intent at one department. Five had bilateral orbital involvement. The tumor was located in the eyelid and extraocular muscles in 23 (44%), conjunctiva in 17 (33%), and lacrimal apparatus in 12 (23%). The histologic features according to the World Heath Organization classification of lymphoid neoplasms was follicular lymphoma in 25, extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue type in 8, diffuse large B-cell lymphoma in 12, mantle cell lymphoma in 6, and peripheral T-cell lymphoma in 1. For the purposes of comparison with the existing literature on orbital lymphomas, the grading system according to the Working Formulation was also recorded. The histologic grade was low in 33 (63%), intermediate in 18 (35%), and high in 1 (2%). All patients were treated with primary radiotherapy alone. The median dose for low-grade tumors was 3000 cGy (range 2000-4020); the median dose for intermediate and high-grade tumors was 4000 cGy (range 3000-5100). A lens-sparing approach was used in 19 patients (37%). Late complications for the lens and cornea were scored according to the subjective, objective, management, and analytic (SOMA) scale of the Late Effects of Normal Tissue (LENT) scoring system. The median follow-up was 55 months (range 6-232). RESULTS: The local control rate was 100% in the 52 orbits treated. The 5-year overall survival and relapse-free survival rate was 73.6% and 65.5%, respectively. Tumor grade and location did not predict for overall survival or relapse-free survival. Seven patients (15%) developed distant recurrence (brain 2, extremity 2, mediastinum 1, liver 1, and retroperitoneum 1). One patient (2%) developed cervical node metastasis. The 5- and 10-year cataract-free survival rate was 56.7% and 32.9%, respectively. Of the 12 lens complications, 8 were LENT Grade 1 and 4 were Grade 3 toxicity. Only male gender predicted for an increased risk of cataract formation. Radiotherapy dose and technique did not predict for cataract formation; however, none of the patients who underwent the lens-sparing technique developed Grade 3 lens toxicity or required surgical correction. Of the nine corneal events, two were Grade 1, four Grade 2, and three were Grade 3 toxicity. Ten dry eyes were recorded; all were mild, and no patient had severe dry eye syndrome. Neovascular glaucoma was seen in 1 patient. No injury to the retina or optic nerve was reported. CONCLUSION: Radiotherapy alone is a highly effective modality in the curative management of primary orbital lymphoma. Most complications were minimal and did not require medical or surgical intervention. Although the use of the lens-sparing technique did not influence the incidence of cataractogenesis, we continue to recommend this approach whenever possible, because our experience indicates a higher grade of toxicity occurs and a higher incidence of corrective surgery is needed in patients treated without lens protection. 相似文献
83.
Monge-Argiles J Maloteaux J Van Den Bergh P Sindic C 《Neurología (Barcelona, Spain)》2002,17(2):110-112
We report a patient with a peripheral neuropathy as the first symptom of sarcoidosis. The systemic illness was proved by the presence of typic granulomes in the bone marrow. The fact that sarcoidosis is the cause for the neuropathy is supported by the temporary relation and by the good response of all clinical picture to the corticosteroid therapy.Sarcoid neuropathy can rarely be the presenting feature of sarcoidosis. 相似文献
84.
Prognostic factors in head and neck rhabdomyosarcoma 总被引:1,自引:0,他引:1
BACKGROUND: Rhabdomyosarcoma comprises less than 1% of all head and neck cancer. The purpose of our study is to review our institutional experience in this disease and to identify possible prognostic factors for patients with head and neck rhabdomyosarcoma. METHODS: One hundred forty patients with rhabdomyosarcoma were identified from 1955-1999 within the tumor registry. Of these cases, 49 (35%) were noted to be primary head and neck rhabdomyosarcomas. Retrospective chart reviews were completed to obtain the following data: age, gender, site, tumor size, histologic findings, Intergroup Rhabdomyosarcoma Study Group, treatment, local control, and survival. RESULTS: The 5-year overall survival and local control rates were 60% +/- 14% and 70% +/- 14%, respectively. Tumor size < or =5 cm (p =.014) and age < or =11 years (p =.036) were predictive of improved survival, whereas age < or =11 years was predictive of improved local control (p =.006). Children < or =11 years with a < or =5-cm tumor have the best overall survival, whereas patients >11 years with a tumor >5 cm have the worst survival. The 5-year survival was intermediate for children < or =11 years with a >5-cm tumor and patients >11 years with a < or =5-cm tumor. Radiotherapy treatment duration < or =45 days in group III disease was associated with improved overall survival but not local control. For the six patients with group I or II disease, who did not receive initial chemotherapy, five had relapses at the primary and/or distant sites. CONCLUSIONS: Improvement in outcome was obtained with multimodality treatment regimens for head and neck rhabdomyosarcoma. Both tumor size and age of patient were found to influence survival. 相似文献
85.
Hans JM van Grinsven Mary H Ward Nigel Benjamin Theo M de Kok 《Environmental health : a global access science source》2006,5(1):26-6
Several authors have suggested that it is safe to raise the health standard for nitrate in drinking water, and save money
on measures associated with nitrate pollution of drinking water resources. The major argument has been that the epidemiologic
evidence for acute and chronic health effects related to drinking water nitrate at concentrations near the health standard
is inconclusive. With respect to the chronic effects, the argument was motivated by the absence of evidence for adverse health
effects related to ingestion of nitrate from dietary sources. An interdisciplinary discussion of these arguments led to three
important observations. First, there have been only a few well-designed epidemiologic studies that evaluated ingestion of
nitrate in drinking water and risk of specific cancers or adverse reproductive outcomes among potentially susceptible subgroups
likely to have elevated endogenous nitrosation. Positive associations have been observed for some but not all health outcomes
evaluated. Second, the epidemiologic studies of cancer do not support an association between ingestion of dietary nitrate
(vegetables) and an increased risk of cancer, because intake of dietary nitrate is associated with intake of antioxidants
and other beneficial phytochemicals. Third, 2–3 % of the population in Western Europe and the US could be exposed to nitrate
levels in drinking water exceeding the WHO standard of 50 mg/l nitrate, particularly those living in rural areas. The health
losses due to this exposure cannot be estimated. Therefore, we conclude that it is not possible to weigh the costs and benefits
from changing the nitrate standard for drinking water and groundwater resources by considering the potential consequences
for human health and by considering the potential savings due to reduced costs for nitrate removal and prevention of nitrate
pollution. 相似文献
86.
87.
88.
Marijke JM Chin A Paw Amika S Singh Johannes Brug Willem van Mechelen 《The international journal of behavioral nutrition and physical activity》2008,5(1):41
Objectives
This paper aims to identify the mediating mechanisms of a school-based obesity prevention program (DOiT). 相似文献89.
Background
The Licensing Act 2003 (The Act) was implemented on the 24th November 2005 across England and Wales. The Act allowed more flexible and longer opening hours for licensed premises. We investigated the effect of The Act on alcohol related attendances to an inner city emergency department in Birmingham, UK. 相似文献90.
Although exposure of LLC-PK1 epithelial cell sheets to phorbol esters (TPA)
causes a near immediate and total decrease of transepithelial electrical
resistance (TER), continuation of exposure for 3 to 4 days results in a
tachyphylactic response as TER begins to return to control levels. Recovery
of TER is maximal by 5 to 6 days, but reaches only 70 to 80% of control
level. A reciprocal change in the transepithelial flux of D-mannitol
indicates that the TER decrease is indicative of an increase in tight
junction permeability. Exposure of cell sheets to TPA for several days also
results in the appearance of multilayered polyp- like foci (PLFs) across
the otherwise one cell layer thick cell sheets. The pattern of penetration
of the electron dense dye, ruthenium red, from the apical surface, across
the tight junction and into the lateral intercellular space indicates that
the tight junctions of the cell sheet become uniformly leaky after acute
exposure to TPA. However, when exposure is continued for several days, only
the junctions of cells in the PLFs manifest leakiness. The decrease in TER
following acute TPA exposure correlates with the translocation of protein
kinase C-alpha (PKC alpha) into a membrane-associated compartment. With
exposure of several days, only a trace of PKC alpha is visible by Western
immunoblot, and this is in the membrane-associated compartment.
Immunofluorescent microscopy indicates that the trace of PKC alpha seen in
the Western immunoblots is ascribable distinctly to cells of the PLFs.
Monolayer areas between PLFs show no discernible immunofluorescent signal.
The data therefore indicate that tight junction barrier function may be
restored in certain areas by the down regulation of PKC alpha from the
membrane-associated compartment. Failure to down regulate may result in the
paracellular leakiness and abnormal cell architecture of the PLFs. Possible
implications of this model for in vivo epithelial tumor promotion are
discussed.
相似文献