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1.
Primitive Neuroectodermal Tumors of the Central Nervous System   总被引:2,自引:0,他引:2  
Controversial issues relating to the pathobiology and classification of central nervous system primitive neuroectodermal tumors (PNETs) have plagued neuropathologists for more than 70 years. Hypotheses advanced in the mid-1920's have remained as fixed concepts in contemporary literature, largely consequent to repetitious support by a small number of neuropathologists despite a growing body of information discrediting these ideas from neuroembryologists, oncologists, neuroscien-tists and pathologists.
Attention has largely focused upon PNETs arising in the cerebellum (commonly known as medul-loblastomas [MBs]), because about 80% of central nervous system (CNS) PNETs originate in this site. It has been asserted that the 20% which do not are biologically different, although most individuals agree that the histological features of PNETs that occur in different sites throughout the CNS are indistinguishable from those growing in the cerebellum.
The historical aspects of this controversy are examined in the face of evidence that there is, in fact, a unique class of CNS tumors which should appropriately be regarded as primitive neuroectodermal in nature. Specifically, a number of different approaches to the problem have yielded data supporting this hypothesis. These approaches include the identification of patterns of expression among a variety of cellular antigens (demonstrated by the use of immunopathological techniques), molecular analyses of cell lines derived from these tumors, experimental production of PNETs and molecular genetic analyses.
Differences of opinion among surgeons, oncologists and radiotherapists are typically resolved by conducting cooperative studies of patients with these tumors who are diagnosed and treated at multiple centers.  相似文献   
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We have established two cell lines, PER-452 and PER-453, from an 8-month-old girl with an extensive pineoblastoma. Characterization of these lines revealed that the proto-oncogenes MYC and MYCN were not amplified, but both cell lines showed MYCN expression comparable to a cell line with 200-fold MYCN amplification. Both cell lines contained an i( 17q). These results support the concept that pineoblastomas belong to a larger group of primitive neuroectodermal tumors of the central nervous system. These two cell lines provide a unique opportunity to investigate the molecular genetic mechanisms underlying these neoplasms further. Genes Chrom Cancer 9:129-135 (1994).© 1994 Wiley-Liss, Inc.  相似文献   
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The COVID‐19 pandemic is a major shock to society in terms of health and economy that is affecting both UK and global food and nutrition security. It is adding to the ‘perfect storm’ of threats to society from climate change, biodiversity loss and ecosystem degradation, at a time of considerable change, rising nationalism and breakdown in international collaboration. In the UK, the situation is further complicated due to Brexit. The UK COVID‐19 Food and Nutrition Security project, lasting one year, is funded by the Economic and Social Research Council and is assessing the ongoing impact of COVID‐19 on the four pillars of food and nutrition security: access, availability, utilisation and stability. It examines the food system, how it is responding, and potential knock on effects on the UK’s food and nutrition security, both in terms of the cascading risks from the pandemic and other threats. The study provides an opportunity to place the initial lessons being learnt from the on‐going responses to the pandemic in respect of food and nutrition security in the context of other long‐term challenges such as climate change and biodiversity loss.  相似文献   
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Aims: Benefits to patients from systemic anti‐cancer therapies (SACT) occur at a cost of significant toxicities that can be life threatening. Published data of SACT mortality outside clinical trials is limited with no published Australia data. We aim to establish local outcomes at a regional Victorian oncology center to allow comparison with limited international data. Methods: An audit was undertaken at Ballarat Health Services to analyze all deaths occurring within 30 and 60 days of receiving SACT (cytotoxic chemotherapy and targeted therapy) for epithelial malignancies and hematological malignancies (excluding acute leukemia), over a 12‐month period. Hormonal therapy was excluded. Results: Between 1 January and 31 December 2008, 378 patients received SACT. In total 13 deaths (3.4%) occurred within 30 days following SACT. Three deaths (23%) were definitely treatment‐related – neutropenic sepsis, pneumocystis pneumonia and bowel perforation, respectively. Eight deaths (62%) were definitely unrelated to treatment. Most deaths were due to disease progression (six patients) For two patients (15%), the cause of death was unknown. Most patients were treated with palliative intent. Most patients were receiving first‐line treatment (seven patients, 50%). A further five deaths (1.3%) occurred 31–60 days after SACT, four of which were due to disease progression. Conclusion: Our local outcome data are comparable to limited current international data. This type of audit reviews local outcomes and identifies factors contributing to mortality in order to improve standards of care. We encourage similar audits to establish national benchmarks of 30‐day mortality rate.  相似文献   
5.
Melioidosis is an infection endemic to Southeast Asia and Northern Australia, and is associated with significant morbidity and mortality. The present report describes a case of chronic melioidosis in a returning traveller from the Philippines. Clinical suspicion of this illness is warranted in individuals with a history of travel to endemic regions. Safety in handling clinical specimens is paramount because laboratory transmission has been described.  相似文献   
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This study aimed to identify providers involved in diagnosing ankylosing spondylitis (AS) following back pain diagnosis in the USA and to identify factors leading to the delay in rheumatology referrals. The Truven Health MarketScan® US Commercial Database was searched for patients aged 18–64 years with back pain diagnosis in a non-rheumatology setting followed by AS diagnosis in any setting during January 2000–December 2012. Patients with a rheumatologist visit on or before AS diagnosis were considered referred. Cox regression was used to determine factors associated with referral time after adjusting for age, sex, comorbidities, physician specialty, drug therapy, and imaging procedures. Of 3336 patients included, 1244 (37 %) were referred to and diagnosed by rheumatologists; the others were diagnosed in primary care (25.7 %), chiropractic/physical therapy (7 %), orthopedic surgery (3.8 %), pain clinic (3.6 %), acute care (3.4 %), and other (19.2 %) settings. Median time from back pain diagnosis to rheumatology referral was 307 days and from first rheumatologist visit to AS diagnosis was 28 days. Referred patients were more likely to be younger (hazard ratio [HR]?=?0.986; p?<?0.0001), male (HR?=?1.15; p?=?0.0163), diagnosed with uveitis (HR?=?1.49; p?=?0.0050), referred by primary care physicians (HR?=?1.96; p?<?0.0001), prescribed non-steroidal anti-inflammatory drugs (HR?=?1.55; p?<?0.0001), disease-modifying antirheumatic drugs (HR?=?1.33; p?<?0.0001), and tumor necrosis factor inhibitors (HR?=?1.40; p?=?0.0036), and to have had spinal/pelvic X-ray prior to referral (HR?=?1.28; p?=?0.0003). During 2000–2012, most patients with AS were diagnosed outside of rheumatology practices. The delay before referral to rheumatology was 10 months; AS diagnosis generally followed within a month. Earlier referral of patients with AS signs and symptoms may lead to more timely diagnosis and appropriate treatment.  相似文献   
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Journal of Thrombosis and Thrombolysis - Oral anticoagulant therapy (OAT) has increased substantially due to the aging population and prevalence rise of atrial fibrillation (AF). Medication...  相似文献   
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