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91.
Computer-aided detection in diagnostic mammography: detection of clinically unsuspected cancers 总被引:1,自引:0,他引:1
Butler SA Gabbay RJ Kass DA Siedler DE O'shaughnessy KF Castellino RA 《AJR. American journal of roentgenology》2004,183(5):1511-1515
OBJECTIVE: We had two objectives: to determine the percentage of women presenting with clinical findings whose diagnostic mammogram led to detection of a breast cancer at a site distant from the original clinical complaint and to assess the performance of computer-aided detection (CAD) on diagnostic mammography. MATERIALS AND METHODS: Three institutions contributed consecutive cases in which a mammogram was obtained to evaluate a clinical finding, after which a histologic diagnosis of breast cancer was made. Clinical data and the mammograms were reviewed to determine the nature of the clinical findings and to document the location and characteristics of 212 biopsy-proven cancers in 197 patients who met the study criteria. Standard four-view breast mammograms were then analyzed by a CAD system. RESULTS: The most common clinical finding was a palpable mass (90%, 177/197), with nipple discharge (5%, 9/197), focal tenderness or pain (2%, 5/197), and miscellaneous complaints (3%, 6/197) also noted. Two separate cancers were found in 7.6% (15/197) of the cases. In another 7.6% (15/197) of the cases, the single diagnosed cancer was not at the location of the specific clinical finding. The CAD system correctly marked 87% (26/30) of those cancers that were clinically unsuspected (i.e., not at the location of the clinical finding). CONCLUSION: Breast cancers occurred at locations other than the site of the presenting clinical finding in 15% (30/197) of patients undergoing diagnostic mammography in whom a cancer was detected. CAD identified 87% of these incidentally detected cancers and may therefore be useful as a detection aid to the radiologist when interpreting diagnostic mammograms. 相似文献
92.
93.
Elevated free hemoglobin and decreased haptoglobin levels are associated with adverse clinical outcomes,unfavorable physiologic measures,and altered inflammatory markers in pediatric cardiac surgery patients 下载免费PDF全文
94.
Effect of tetanus toxin on the accumulation of the permeant lipophilic cation tetraphenylphosphonium by guinea pig brain synaptosomes 总被引:7,自引:0,他引:7 下载免费PDF全文
Sofia Ramos Evelyn F. Grollman Pedro S. Lazo Sherry A. Dyer William H. Habig M. Carolyn Hardegree H. Ronald Kaback Leonard D. Kohn 《Proceedings of the National Academy of Sciences of the United States of America》1979,76(10):4783-4787
Accumulation of the permeant lipophilic cation [(3)H]tetraphenylphosphonium (TPP(+)) by synaptosome preparations from guinea pig brain cerebral cortex is inhibited 1:10 by medium containing 193 mM K(+) and by veratridine. A further 1:10 to 1:15 decrease in TPP(+) uptake occurs under nitrogen and in the presence of mitochondrial inhibitors such as oligomycin, whereas starvation and succinate supplementation have no effect. These data indicate that, in analogy to intact neurons, there is an electrical potential (DeltaPsi, interior negative) of -60 to -80 mV across the synaptosomal membrane that is due primarily to a K(+) diffusion gradient (K(+) (in)-->K(+) (out)). The data also indicate that mitochondria entrapped within the synaptosome but not free mitochondria make a large contribution to the TPP(+) concentration gradients observed.Conditions are defined in which tetanus toxin binds specifically and immediately to synaptosomes in media used to measure TPP(+) uptake. Under these conditions tetanus toxin induces dose-dependent changes in TPP(+) uptake that are blocked by antitoxin and not mimicked by biologically inactivated toxin preparations. The effect of tetanus toxin on TPP(+) uptake is not evident in the presence of 193 mM K(+) or veratridine but remains under conditions known to abolish the mitochondrial DeltaPsi. Moreover, tetanus toxin has no effect on TPP(+) uptake by isolated synaptosomal mitochondria. The results thus define an in vitro action of tetanus toxin on the synaptosomal membrane that can be correlated with biological potency in vivo and is consistent with the in vivo effects of tetanus toxin on neuronal transmission. 相似文献
95.
Cholinergic stimulation blocks endothelial cell activation and leukocyte recruitment during inflammation 总被引:20,自引:0,他引:20 下载免费PDF全文
Saeed RW Varma S Peng-Nemeroff T Sherry B Balakhaneh D Huston J Tracey KJ Al-Abed Y Metz CN 《The Journal of experimental medicine》2005,201(7):1113-1123
Endothelial cell activation plays a critical role in regulating leukocyte recruitment during inflammation and infection. Based on recent studies showing that acetylcholine and other cholinergic mediators suppress the production of proinflammatory cytokines via the alpha7 nicotinic acetylcholine receptor (alpha7 nAChR) expressed by macrophages and our observations that human microvascular endothelial cells express the alpha7 nAChR, we examined the effect of cholinergic stimulation on endothelial cell activation in vitro and in vivo. Using the Shwartzman reaction, we observed that nicotine (2 mg/kg) and the novel cholinergic agent CAP55 (12 mg/kg) inhibit endothelial cell adhesion molecule expression. Using endothelial cell cultures, we observed the direct inhibitory effects of acetylcholine and cholinergic agents on tumor necrosis factor (TNF)-induced endothelial cell activation. Mecamylamine, an nAChR antagonist, reversed the inhibition of endothelial cell activation by both cholinergic agonists, confirming the antiinflammatory role of the nAChR cholinergic pathway. In vitro mechanistic studies revealed that nicotine blocked TNF-induced nuclear factor-kappaB nuclear entry in an inhibitor kappaB (IkappaB)alpha- and IkappaBepsilon-dependent manner. Finally, with the carrageenan air pouch model, both vagus nerve stimulation and cholinergic agonists significantly blocked leukocyte migration in vivo. These findings identify the endothelium, a key regulator of leukocyte trafficking during inflammation, as a target of anti-inflammatory cholinergic mediators. 相似文献
96.
Foster AM Armstrong J Buckley A Sherry J Young T Foliaki S James-Hohaia TM Theadom A McPherson KM 《Disability and rehabilitation》2012,34(22):1855-1862
Purpose: After a moderate to severe traumatic brain injury, it is widely recommended that family members be actively engaged in the client's rehabilitation journey because evidence suggests that this is associated with better outcomes. The ability of family members to fully engage in rehabilitation may be hindered by the barriers (logistical and psychological) they encounter. However, rehabilitation services can facilitate family engagement through a person-centred approach that provides support to remove barriers. Limited published guidance exists regarding practical and effective methods for delivering such support. This paper describes how one rehabilitation service has developed an eight-tiered approach. Key messages and implications: Family support is provided by explicit structuring of services to include (i) early engagement, (ii) meeting cultural needs, (iii) keeping families together, (iv) actively listening, (v) active involvement, (vi) education, (vii) skills training, and (viii) support for community re-integration. Implementation of these support strategies are individualised based on the expressed needs of each family. Families report a high level of satisfaction with the service. Conclusion: A practice-based quality improvement model identified challenges, implemented changes, and observed/evaluated the results to successfully develop a multifaceted strategy for supporting families, thereby encouraging their engagement in rehabilitation. Ongoing refinements and evaluation are planned. [Box: see text]. 相似文献
97.
Robert Applegate MD James Hermiller MD Jerome Williams MD Paul Gordon MD Julie Doostzadeh PhD Sherry Cao MS Xiaolu Su MS Krishnankutty Sudhir MD Alexandra Lansky MD Charles Simonton MD Gregg Stone MD 《Catheterization and cardiovascular interventions》2010,76(5):644-651
Objective: To evaluate whether an everolimus‐eluting stent (EES) with thinner stent struts and polymer results in less periprocedural myonecrosis and adverse outcomes. Background: Higher periprocedural myocardial infarction (MI) rates have been reported with the TAXUS® EXPRESS2 paclitaxel‐eluting stent (PES) compared to the bare metal EXPRESS2® stent due to more frequent side branch compromise, presumably attributable to the thickness of the stent/polymer on the PES. Methods: In the SPIRIT III trial, we identified 113 patients in the XIENCE V® EES group and 63 patients in the TAXUS EXPRESS2 PES group who met the criteria of having a lesion with a jailed side branch (<2 mm diameter, and <50% stenosis). Two‐year clinical outcomes were evaluated. Results: A periprocedural increase in Creatine Kinase‐MB >1× upper normal level occurred in 9.0% of EES compared to 29.7% of PES patients with jailed side branches, P = 0.01. Through 2 years, major adverse cardiac events (MACE; cardiac death, MI, or target lesion revascularization [TLR]) occurred in 6.8% of EES and 19.0% of PES jailed side branch patients (P = 0.03), with numerically lower rates of MI (2.9% vs. 10.3%, P = 0.07) and TLR (3.9% vs. 10.3%, P = 0.17) in the EES group, with comparable rates of cardiac death (1.9% vs. 1.7%, P = 1.00). Conclusions: In this post‐hoc analysis of the SPIRIT III RCT, patients undergoing stenting of target lesions with jailed side branches with the thin strut and polymer XIENCE V EES compared to the thicker strut TAXUS PES had lower rates of MACE through 2 years due to fewer MIs and TLRs. © 2010 Wiley‐Liss, Inc. 相似文献
98.
99.
Aribi A Bueso-Ramos C Estey E Estrov Z O'Brien S Giles F Faderl S Thomas D Kebriaei P Garcia-Manero G Pierce S Cortes J Kantarjian H Ravandi F 《British journal of haematology》2007,138(2):213-216
Biphenotypic acute leukaemia (BAL) is a rare type of leukaemia. Whether patients with BAL should be treated with regimens designed for acute myeloid leukaemia (AML), acute lymphocytic leukaemia (ALL) or both remain unclear. We have reviewed the clinical data for 31 BAL patients. Most patients co-expressed B-lymphoid and myeloid markers. No specific chromosomal abnormality was identified. The majority of the patients were treated with regimens devised for treating ALL. Seven patients were treated with regimens designed for AML. Complete remission (CR) rates of 78% and 57% were noted respectively. The overall survival probability at 2 years was 60%. 相似文献
100.
Appelbaum FR Kopecky KJ Tallman MS Slovak ML Gundacker HM Kim HT Dewald GW Kantarjian HM Pierce SR Estey EH 《British journal of haematology》2006,135(2):165-173
To better understand the spectrum of adult acute myeloid leukaemia (AML) associated with core binding factor (CBF) translocations, 370 patients with newly diagnosed CBF-associated AML were analysed. Patients' age ranged from 16-83 years (median 39 years) with a slight male predominance (55%); 53% had inv(16); 47% had t(8;21). Patients with t(8;21) tended to be younger (P = 0.056), have lower peripheral blood white cell counts (P < 0.0001) and were more likely to have additional cytogenetic abnormalities (P < 0.0001). Loss of sex chromosome, del(9q) and complex abnormalities were more common among patients with t(8;21), while +22 and +21 were more common with inv(16). Overall, 87% [95% confidence interval (CI) 83-90%] of patients achieved complete response (CR) with no difference between t(8;21) and inv(16); however, the CR rate was lower in older patients due to increased resistant disease and early deaths. Ten-year overall survival (OS) was 44% (95% CI 39-50%) and, in multivariate analysis, was shorter with increasing age (P < 0.0001), increased peripheral blast percentage (P = 0.0006), in patients with complex cytogenetic abnormalities in addition to the CBF translocation (P = 0.021), and in patients with t(8;21) (P = 0.025). OS was superior in patients who received regimens with high-dose cytarabine, a combination of fludarabine and intermediate-dose cytarabine, or haematopoietic cell transplantation. 相似文献