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81.
A 38-year-old woman presented with an infiltrative tumor of the right frontal lobe and genu of the corpus callosum that was deemed only partially resectable. A stereotactic biopsy was performed, which revealed a right frontal oligoastrocytoma that had some anaplastic features as well as allelic loss of chromosome arms 1p and 19q. The patient was treated with temozolomide for 24 months. The partial response of the tumor to chemotherapy rendered the lesion amenable to gross total resection, which was performed subsequently. The patient remains alive and well without evidence of recurrence 7 months after resection and 48 months after initial diagnosis. Thus, preoperative chemotherapy decreased tumor mass to a degree that subsequently enabled a gross total resection. This treatment strategy, although common in the treatment of other solid tumors, is rarely utilized in adult neuro-oncology and raises another potential role for chromosome testing in oligodendroglial tumor management. 相似文献
82.
Minimally invasive surgical (MIS) procedures have become commonplace in modern surgical practice. The term minimally invasive surgery has been and continues to be interchangeably applied to describe laparoscopic, laparoscopic-assisted, thoracoscopic, and telesurgical (robotic) procedures. Minimally invasive surgical procedures for the treatment of benign and malignant disorders of the esophagus are being developed, refined, and clinically applied in parallel with the exponential availability of novel technologies and instrumentation. Herein, we review the progression from laparoscopic/thoracoscopic esophagectomy to telesurgical esophagectomy, presently termed minimally invasive esophagectomy, and describe the telesurgical procedure as well as early the clinical outcome experience. 相似文献
83.
Harrison D Lloyd-Smith R Khazei A Hunte G Lepawsky M 《Current sports medicine reports》2005,4(5):275-281
Primary care and sports medicine physicians are frequently consulted on medical clearance for prospective recreational divers.
We discuss four common and controversial medical conditions—asthma, diabetes mellitus, coronary artery disease, and patent
foramen ovale—as they relate to fitness to dive. For each condition we review the relevant anatomy and physiology, current
recommendations, and the pertinent medical literature. Finally, we offer evidence-based recommendations regarding fitness
to dive for potential divers with these conditions. 相似文献
84.
Braxton EE Ehrlich GD Hall-Stoodley L Stoodley P Veeh R Fux C Hu FZ Quigley M Post JC 《Neurosurgical review》2005,28(4):249-255
Bacterial biofilms have recently been shown to be important in neurosurgical device-related infections. Because the concept of biofilms is novel to most practitioners, it is important to understand that both traditional pharmaceutical therapies and host defense mechanisms that are aimed at treating or overcoming free-swimming bacteria are largely ineffective against the sessile bacteria in a biofilm. Bacterial biofilms are complex surface-attached structures that are composed of an extruded extracellular matrix in which the individual bacteria are embedded. Superimposed on this physical architecture is a complex system of intercellular signaling, termed quorum sensing. These complex organizational features endow biofilms with numerous microenvironments and a concomitant number of distinct bacterial phenotypes. Each of the bacterial phenotypes within the biofilm displays a unique gene expression pattern tied to nutrient availability and waste transport. Such diversity provides the biofilm as a whole with an enormous survival advantage when compared to the individual component bacterial cells. Thus, it is appropriate to view the biofilm as a multicellular organism, akin to metazoan eukaryotic life. Bacterial biofilms are much hardier than free floating or planktonic bacteria and are primarily responsible for device-related infections. Now that basic research has demonstrated that the vast majority of bacteria exist in biofilms, the paradigm of biofilm-associated chronic infections is spreading to the clinical world. Understanding how these biofilm infections affect patients with neurosurgical devices is a prerequisite to developing strategies for their treatment and prevention. 相似文献
85.
Microchimerism in transfused trauma patients is associated with diminished donor-specific lymphocyte response 总被引:3,自引:0,他引:3
Utter GH Owings JT Lee TH Paglieroni TG Reed WF Gosselin RC Holland PV Busch MP 《The Journal of trauma》2005,58(5):925-31; discussion 931-2
BACKGROUND: Blood transfusion can result in long-term survival of donor leukocyte subpopulations, or microchimerism, in the peripheral blood of injured patients. Neither injury severity nor the number of transfusions is associated with its occurrence. We sought to determine whether changes in general or antigen-specific lymphocyte activation may be associated with the subsequent development of microchimerism. METHODS: We evaluated 63 transfused trauma patients, which we compared with 10 non-transfused trauma patients and 10 healthy control subjects. Of the 63 transfused patients, 31 were known to have evidence of microchimerism at hospital discharge with real-time quantitative PCR for non-recipient HLA DR alleles. We assessed lymphocyte response to phytohemagglutinin (PHA) using blood sampled upon arrival to the hospital (before transfusion) and at discharge. We performed one-way mixed leukocyte cultures (MLC) with pre-transfusion recipient specimens to assess recipient lymphocyte response to mitomycin-C treated donor cells and vice versa. RESULTS: Lymphocyte response to PHA in microchimeric transfusion recipients was lower at admission (before transfusion) and discharge than in non-microchimeric recipients. Lymphocytes from microchimeric patients had less response to donor cells than did lymphocytes from non-microchimeric patients. Microchimeric patients also more frequently had diminished lymphocyte response to a single blood donor on MLC. CONCLUSIONS: Transfusion-associated microchimerism is correlated with diminished response to mitogen challenge as well as to specific alloantigenic challenges. This microchimerism is predated by diminished lymphocyte response to a specific blood donor in many instances. The blood donor associated with this diminished alloantigenic lymphocyte response may be the source of microchimeric cells present in the recipient. 相似文献
86.
This article describes the evaluation of the HIV/AIDS communication aspect of the multi media Soul City health promotion intervention in South Africa. The intervention consists of a television and radio drama and print material. The evaluation was multifaceted with a before and after national survey and a national qualitative study. In the before and after survey change was measured and then multiple regression analysis was performed to assess the variables associated with the change. The qualitative study consisted of focus group discussions, which were analysed thematically. The studies show that there are numerous instances of community change and how the change is mediated at the community level. The studies also describe the change at a number of levels of the described behaviour change model for individuals. 相似文献
87.
Roth FS Kokoska MS Awwad EE Martin DS Olson GT Hollier LH Hollenbeak CS 《The Journal of craniofacial surgery》2005,16(3):394-399
The introduction of computed tomography (CT) in 1972 revolutionized the radiographic evaluation of patients who have experienced trauma. However, panoramic tomography (PT) continued to be superior in sensitivity to CT in the identification of mandible fractures and has been considered the gold standard for the past 3 decades. In 1989, a faster, higher-resolution spiral or helical CT (HCT) became widely available, and its efficacy in multiplanar evaluation and diagnosis of fractures of the upper two thirds of the face has been well established. The sensitivity of this new-generation HCT in comparison to PT in the detection of mandible fractures has not been determined. The purpose of this study was to compare the sensitivity, physician interpretation error, and interphysician agreement of HCT and PT in the identification of mandible fractures. The number and anatomical location of mandible fractures identified by HCT and PT was not significantly different. However, the number and location of 96% of fractures identified by HCT was agreed on by neuroradiologists compared with only 91% of fractures identified by PT. Furthermore, the interphysician agreement when no fracture was identified was 96% by HCT versus only 81% by PT. In conclusion, HCT has enhanced imaging quality, equivalent sensitivity in identification of fractures, decreased interpretation error, and greater interphysician agreement in the identification of mandible fractures. HCT has surpassed PT as the current gold standard for the radiographic evaluation and diagnosis of mandible fractures. 相似文献
88.
Whiteside GT Boulet JM Walker K 《The Journal of pharmacology and experimental therapeutics》2005,314(3):1234-1240
The role of opioid receptors located in the central nervous system (CNS) and peripheral nervous system in inflammatory pain is well established. In contrast, although it is has been shown that mu agonists can reduce other manifestations of inflammation, such as edema, the mechanism of action remains unclear. In this study, we have activated mu receptors located centrally, those located peripherally, and those located both centrally and peripherally and compared the effects on pain and edema using the rat carrageenan model of acute inflammation. Activation of mu receptors located only in the periphery, by administration of the peripheralized mu agonist [8-(3,3-diphenyl-propyl)-4-oxo-1-phenyl-1,3,8-triaza-spiro[4.5]dec-3-yl]-acetic acid (DiPOA) or local administration of morphine, resulted in antihyperalgesia (30 mg/kg DiPOA, 83% inhibition; 100 microg/rat morphine, 75% inhibition) without affecting edema. In contrast, activation of both central and peripheral mu receptors using systemically administered morphine resulted in antihyperalgesia (1 mg/kg, 80% inhibition) and inhibition of edema (10 mg/kg, 54% inhibition). Finally, activation of only receptors located in the CNS, by central administration of DiPOA or systemic administration of morphine after block of only the peripheral mu receptors using q-naltrexone, resulted in a significant reduction in edema. Our findings confirm the role of peripheral mu receptors in the pathology of pain associated with acute inflammation and argue against the involvement of these receptors in edema formation. Furthermore, our data demonstrate that activation of mu receptors in the brain inhibits carrageenan-induced edema and suggest that the antiedematous effect of morphine is due to action at central receptors alone. 相似文献
89.
Lee TH Paglieroni T Utter GH Chafets D Gosselin RC Reed W Owings JT Holland PV Busch MP 《Transfusion》2005,45(8):1280-1290
BACKGROUND: Long-term white blood cell (WBC) microchimerism (MC), of at least 2 years, has been reported in trauma patients receiving fresh nonleukoreduced (non-LR) blood. It is unknown, however, whether this occurs with LR blood products that are nearly devoid of WBCs. Twenty-seven patients transfused with LR and non-LR blood products were studied after severe traumatic injury. A secondary aim was to explore donor-recipient mixed lymphocyte reactivity in vitro. STUDY DESIGN AND METHODS: To quantify MC, allele-specific real-time polymerase chain reaction assays were developed targeting HLA Class II sequence polymorphisms. Extensive validation showed that these assays reliably detect a single copy of target sequence in a complex allogeneic background without false positivity. RESULTS: At a median follow-up of 26 months (range, 24-39 months), long-term MC was observed in 3 of 20 patients (15%) who received non-LR blood products and 2 of 7 (29%) who received LR blood products. The maximum MC ranged from 0.40 to 4.90 percent of circulating WBCs and appeared, by Class II genotype analysis, to be attributable to a single donor. CONCLUSION: It is concluded that robust levels of long-term MC, apparently traceable to a single donor, occur at similar frequency despite leukoreduction of transfused blood products. Exploratory analysis of donor-recipient mixed lymphocyte reactivity suggests that long-term MC may require a state of bidirectional tolerance before transfusion. 相似文献
90.