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BackgroundThe National Athletic Treatment, Injury and Outcomes Network Surveillance Program (NATION-SP) was established in 2011 to provide a comprehensive appraisal of injuries sustained by high school student-athletes who received services from athletic trainers (ATs). The purpose of this article is to update the surveillance methods of the NATION-SP for data reported during the 2014–2015 through 2018–2019 academic years.Surveillance System StructureThe NATION-SP used a rolling recruitment model to identify a convenience sample of US high schools with access to ATs. The ATs at participating institutions volunteered to contribute data via electronic medical records systems; common data elements were then pushed to and maintained by the Datalys Center for Sports Injury Research and Prevention. The ATs completed detailed reports on each injury, including the condition and circumstances. The treatments component was used to comprehensively assess the services provided to athletes by ATs. The outcomes companion component was developed to monitor patient-reported outcomes after athletic injury.SummaryThe NATION-SP continues to serve a critical purpose in informing injury-prevention and treatment efforts among high school athletes.  相似文献   
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Late cluster implant failures can be one of the most devasting outcomes of implant therapy for patients. It can have anatomic, functional, psychological and financial consequences for patients, and sometimes the loss of residual bone can preclude subsequent implant placement. Fortunately, management of cluster implant failures in the maxilla can be mitigated by using implant anchorage from remote sites like zygomatic and pterygoid regions. Few reports exist in the literature that have described the management of cluster implant failure using extra‐maxillary implants such as zygomatic and pterygoid implants. This case report describes the management of a female patient with bruxism who experienced late cluster implant failure in the maxilla after 9 years of function with an overdenture. Due to the loss of residual bone, subsequent implant therapy involved the use of bilateral zygomatic, pterygoid and anterior maxillary implants, which were immediately loaded and thereafter used to support a complete arch fixed implant‐supported zirconia prosthesis.  相似文献   
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Staphylococcal pathogenicity islands (SaPIs) carry superantigen and resistance genes and are extremely widespread in Staphylococcus aureus and in other Gram-positive bacteria. SaPIs represent a major source of intrageneric horizontal gene transfer and a stealth conduit for intergeneric gene transfer; they are phage satellites that exploit the life cycle of their temperate helper phages with elegant precision to enable their rapid replication and promiscuous spread. SaPIs also interfere with helper phage reproduction, blocking plaque formation, sharply reducing burst size and enhancing the survival of host cells following phage infection. Here, we show that SaPIs use several different strategies for phage interference, presumably the result of convergent evolution. One strategy, not described previously in the bacteriophage microcosm, involves a SaPI-encoded protein that directly and specifically interferes with phage DNA packaging by blocking the phage terminase small subunit. Another strategy involves interference with phage reproduction by diversion of the vast majority of virion proteins to the formation of SaPI-specific small infectious particles. Several SaPIs use both of these strategies, and at least one uses neither but possesses a third. Our studies illuminate a key feature of the evolutionary strategy of these mobile genetic elements, in addition to their carriage of important genes—interference with helper phage reproduction, which could ensure their transferability and long-term persistence.  相似文献   
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Background

The levels and clinical relevance of Th17 cells and other interleukin-17-producing cells have not been analyzed in chronic lymphocytic leukemia. The objective of this study was to quantify blood and tissue levels of Th17 and other interleukin-17-producing cells in patients with this disease and correlate blood levels with clinical outcome.

Design and Methods

Intracellular interleukin-17A was assessed in blood and splenic mononuclear cells from patients with chronic lymphocytic leukemia and healthy subjects using flow cytometry. Interleukin-17A-producing cells were analyzed in formalin-fixed, paraffin-embedded spleen and lymph node sections using immunohistochemistry and immunofluorescence.

Results

The absolute numbers of Th17 cells in peripheral blood mononuclear cells and the percentages of Th17 cells in spleen cell suspensions were higher in patients with chronic lymphocytic leukemia than in healthy subjects; in six out of eight paired chronic lymphocytic leukemia blood and spleen sample comparisons, Th17 cells were enriched in spleen suspensions. Circulating Th17 levels correlated with better prognostic markers and longer overall survival of the patients. Two “non-Th17” interleukin-17-expressing cells were identified in chronic lymphocytic leukemia spleens: proliferating cells of the granulocytic lineage and mature mast cells. Granulocytes and mast cells in normal spleens did not express interleukin-17. Conversely, both chronic lymphocytic leukemia and healthy lymph nodes contained similar numbers of interleukin-17+ mast cells as well as Th17 cells.

Conclusions

Th17 cells are elevated in chronic lymphocytic leukemia patients with better prognostic markers and correlate with longer survival. Furthermore, non-Th17 interleukin-17A-expressing cells exist in chronic lymphocytic leukemia spleens as maturing granulocytes and mature mast cells, suggesting that the microenvironmental milieu in leukemic spleens promotes the recruitment and/or expansion of Th17 and other IL-17-expressing cells. The pathophysiology of Th17 and non-Th17-interleukin-producing cells in chronic lymphocytic leukemia and their distributions and roles in this disease merit further study.  相似文献   
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A fifty-year-old male had an echocardiogram for an abnormal electrocardiogram; it revealed a left ventricular mass. A cardiac catheterization revealed normal coronary arteries and a fine tumor blush of the cardiac tumor with feeding arteries from the circumflex as well as the second diagonal coronary vessels. Due to increased risk of embolization, he underwent surgery via a transatrial approach and a 1.5 cm cavernous-capillary hemangioma was removed from the base of the posteromedial papillary muscle. Primary tumors of the heart are rare, and the symptoms and signs depend on the location and size of the tumor. Coronary angiography remains an integral part in the evaluation of cardiac tumors and often can reveal a characteristic 'tumor blush.' The natural history of the tumor is unpredictable and excision of the tumor remains the treatment of choice. We present a rare case of characteristic angiographic tumor blush of a left ventricular cardiac hemangioma with feeding arteries from both the left anterior descending as well as the circumflex arteries. This rare two-system supply was due to the intracavitary location of the hemangioma, and fortunately did not pose any excessive difficulty in mobilization and excision during surgery.  相似文献   
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