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61.
18F]fluorodeoxyglucose uptake by positron emission tomography predicts outcome of non-small-cell lung cancer. 总被引:9,自引:0,他引:9
Ryohei Sasaki Ritsuko Komaki Homer Macapinlac Jeremy Erasmus Pamela Allen Kenneth Forster Joe B Putnam Roy S Herbst Cesar A Moran Donald A Podoloff Jack A Roth James D Cox 《Journal of clinical oncology》2005,23(6):1136-1143
PURPOSE: To determine whether the standardized uptake value (SUV) of [(18)F]fluorodeoxyglucose uptake by positron emission tomography could be a prognostic factor for non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: One hundred sixty-two patients with stage I to IIIb NSCLC were analyzed. Overall survival (OS), disease-free survival (DFS), distant metastasis-free survival (DMFS), and local-regional control (LRC) were calculated by the Kaplan-Meier method and evaluated with the log-rank test. The prognostic significance was assessed by univariate and multivariate analyses. RESULTS: There were 93 patients treated with surgery and 69 patients treated with radiotherapy. A cutoff of 5 for the SUV for the primary tumor showed the best discriminative value. The SUV for the primary tumor was a significant predictor of OS (P = .02) in both groups. Low SUVs (= 5.0) showed significantly better DFS rates than those with high SUVs (> 5.0; surgery group, P = .02; radiotherapy group, P = .0005). Low SUVs (= 5.0) indicated a significantly better DFS than those with high SUVs (> 5.0; stage I or II, P = .02; stage IIIa or IIIb, P = .004). However, using the same cutoff point of 5, the SUV for regional lymph nodes was not a significant indicator for DFS (P = .19), LRC (P = .97), or DMFS (P = .17). The multivariate analysis showed that the SUV for the primary tumor was a significant prognostic factor for OS (P = .03) and DFS (P = .001). CONCLUSION: The SUV of the primary tumor was the strongest prognostic factor among the patients treated by curative surgery or radiotherapy. 相似文献
62.
Malignant phyllodes tumour is an uncommon breast neoplasm which undergoes osteosarcomatous differentiation in 1.3% of cases. We document the plain film, CT and scintigraphic features of a case of pulmonary metastases from this rare primary tumour. 相似文献
63.
The Center for Environmental Health Sciences (CEHS) Conference entitled “Directions and Needs in Asbestos Research: New Insights” was held at the University of Montana in Missoula on July 28 and 29, 2005. Researchers, physicians, health care workers, and federal agency representatives from around the country met for a cross-disciplinary exploration of many issues related to asbestos research. Topics included community and psychosocial issues in biomedical research, asbestos exposure assessment, assessment and mechanisms of asbestos-related diseases, and new research directions. This meeting report is a summary of the conference presentations, and of the topics identified for future research directions. This conference was a follow-up to one hosted by the CEHS in June 2002, and continued to take advantage of opportunities to work with a unique population in Libby, MT, where significant asbestos exposures have occurred due to the mining of asbestos-contaminated vermiculite. The goals of this conference were to bring together experts from diverse fields to identify progress made since the last conference and to develop new research avenues that would allow us to address the research needs in emerging asbestos-exposed populations. Participants indicated that these objectives were met, and expressed enthusiasm for follow-up conferences, tentatively planned for the summer of 2007, to maintain the dialog that has been established regarding directions and needs in asbestos research. Selected papers from the conference are presented in this issue of Inhalation Toxicology. 相似文献
64.
Christopher D. Putnam Stephanie R. Allen-Soltero Sandra L. Martinez Jason E. Chan Tikvah K. Hayes Richard D. Kolodner 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(47):E3251
Unbiased forward genetic screens for mutations causing increased gross chromosomal rearrangement (GCR) rates in Saccharomyces cerevisiae are hampered by the difficulty in reliably using qualitative GCR assays to detect mutants with small but significantly increased GCR rates. We therefore developed a bioinformatic procedure using genome-wide functional genomics screens to identify and prioritize candidate GCR-suppressing genes on the basis of the shared drug sensitivity suppression and similar genetic interactions as known GCR suppressors. The number of known suppressors was increased from 75 to 110 by testing 87 predicted genes, which identified unanticipated pathways in this process. This analysis explicitly dealt with the lack of concordance among high-throughput datasets to increase the reliability of phenotypic predictions. Additionally, shared phenotypes in one assay were imperfect predictors for shared phenotypes in other assays, indicating that although genome-wide datasets can be useful in aggregate, caution and validation methods are required when deciphering biological functions via surrogate measures, including growth-based genetic interactions. 相似文献
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67.
Deformable sickle erythrocytes have been reported by Mohandas and Evans to be more adherent to vascular endothelium than rigid irreversibly sickled cells (ISC). To define the clinical implications of this finding we have determined genetic, hematological, clinical, and rheological characteristics of sickle erythrocytes obtained from 65 patients with sickle cell anemia and fetal hemoglobin (Hb F) levels less than 15%. The alpha-globin gene number had a significant effect on the hematological parameters, the percentage of dense cells, ISC number, and HB A2 levels. The presence or absence of alpha thalassemia, however, had no effect on the frequency and severity of the sickle cell painful crisis (r = 0.06, P greater than .05). RBC deformability, determined by an ektacytometer, showed great heterogeneity among patients with three or four alpha-globin genes. Linear regression analyses of the data showed significant positive correlation of the frequency and severity of the painful crisis with RBC deformability (r = 0.49, P less than .001), and negative correlations with the percentage of dense cells (r = -0.37, P = .002), and the percentage of ISC (r = -0.46, P less than .001). We propose that the more deformable the sickle RBC are, the greater their adherence to vascular endothelium, and the more they cause vaso-occlusive crises, RBC deformability and the percentage of dense cells (or ISC) seem to have a predictive value of the frequency and severity of painful crises in sickle cell anemia. 相似文献
68.
The spectrum of pediatric eosinophilic esophagitis beyond infancy: a clinical series of 30 children 总被引:9,自引:0,他引:9
Orenstein SR Shalaby TM Di Lorenzo C Putnam PE Sigurdsson L Mousa H Kocoshis SA 《The American journal of gastroenterology》2000,95(6):1422-1430
OBJECTIVES: Eosinophilic esophagitis, previously confused with esophageal inflammation due to gastroesophageal reflux, has recently begun to be distinguished from it. We undertook this analysis of our large series of children with the condition to clarify its spectrum: its presenting symptoms; its relation to allergy, respiratory disease, and reflux; its endoscopic and histological findings; and its diagnosis and therapy. METHODS: We analyzed the details of our clinical series of 30 children with eosinophilic esophagitis, defining it as > or =5 eosinophils per high power field in the distal esophageal epithelium. Retrospective chart review was supplemented by prospective, blinded, duplicate quantitative evaluation of histology specimens, and by telephone contact with some families to clarify subsequent course. Presentation and analysis of the series as a whole is preceded by a case illustrating a typical presentation with dysphagia and recurrent esophageal food impactions. RESULTS: Presenting symptoms encompass vomiting, pain, and dysphagia (some with impactions or strictures). Allergy, particularly food allergy, is an associated finding in most patients, and many have concomitant asthma or other chronic respiratory disease. A subtle granularity with furrows or rings is newly identified as the endoscopic herald of histological eosinophilic esophagitis. Histological characteristics include peripapillary or juxtaluminal eosinophil clustering in certain cases. Association with eosinophilic gastroenteritis occurs, but is not common. Differentiation from gastroesophageal reflux disease is approached by analyzing eosinophil density and response to therapeutic trials. Therapy encompasses dietary elimination and anti-inflammatory pharmacotherapy. CONCLUSION: Awareness of the spectrum of eosinophilic esophagitis should promote optimal diagnosis and treatment of this elusive entity, both in children and in adults. 相似文献
69.
Structural model of human ceruloplasmin based on internal triplication, hydrophilic/hydrophobic character, and secondary structure of domains. 总被引:9,自引:4,他引:9 下载免费PDF全文
T L Ortel N Takahashi F W Putnam 《Proceedings of the National Academy of Sciences of the United States of America》1984,81(15):4761-4765
A molecular model for the structure of human ceruloplasmin is proposed that is based on the determination of the complete amino acid sequence, studies of the products of limited proteolytic cleavage, calculations of the hydrophilic/hydrophobic character (hydropathy profile), and predictions of the local secondary structure. This multicopper oxidase (Mr approximately 132,000) consists of a single polypeptide chain (1046 amino acid residues) with four attached glucosamine oligosaccharides. Computer-assisted statistical analysis of the internal repetition in the amino acid sequence confirms that the entire polypeptide chain is divided into three contiguous homology units, each containing about 350 amino acid residues. Each homology unit is subdivided into three domains, designated A1, A2, and B, that differ in structure and probably in function. Calculations of the hydropathy profile and predictions of the secondary structure support a molecular model based on internal repetition of three homology units and help to identify characteristic features of the interdomain junctions. The alignment scores for internal duplication of pairings of the three homology units of ceruloplasmin exceed the scores yet reported for contiguous internal duplication of any other protein. This highly significant evidence for intragenic repetition suggests that the ceruloplasmin molecule evolved by tandem triplication of ancestral genes coding for a primordial copper oxidase. 相似文献
70.
Vishnu Prasad Pulappadi Smita Manchanda Pritviraj SK Smriti Hari 《The British journal of radiology》2021,94(1117)
Corpus luteum rupture presenting as acute abdomen is an underdiagnosed condition. Though a self-limiting entity, its differentiation from other causes is essential to prevent unnecessary surgical procedures. The radiologist should be aware of the possibility of a ruptured haemorrhagic ovarian cyst in a female of reproductive age group presenting with pelvic pain and a large amount of haemorrhagic ascites. Imaging characteristically reveals a thick-walled cystic structure in the adnexa with internal echoes, focal discontinuity or irregularity of its wall with haemoperitoneum. While sonography is usually indicative of corpus luteum rupture, cross-sectional imaging (CT/MRI) can be used to confirm the diagnosis. 相似文献