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61.
Measurement of mesothelioma on thoracic CT scans: a comparison of manual and computer-assisted techniques 总被引:4,自引:0,他引:4
Armato SG Oxnard GR MacMahon H Vogelzang NJ Kindler HL Kocherginsky M Starkey A 《Medical physics》2004,31(5):1105-1115
Our purpose in this study was to evaluate the variability of manual mesothelioma tumor thickness measurements in computed tomography (CT) scans and to assess the relative performance of six computerized measurement algorithms. The CT scans of 22 patients with malignant pleural mesothelioma were collected. In each scan, an initial observer identified up to three sites in each of three CT sections at which tumor thickness measurements were to be made. At each site, five observers manually measured tumor thickness through a computer interface. Three observers repeated these measurements during three separate sessions. Inter- and intra-observer variability in the manual measurement of tumor thickness was assessed. Six automated measurement algorithms were developed based on the geometric relationship between a specified measurement site and the automatically extracted lung regions. Computer-generated measurements were compared with manual measurements. The tumor thickness measurements of different observers were highly correlated (r > or = 0.99); however, the 95% limits of agreement for relative inter-observer difference spanned a range of 30%. Tumor thickness measurements generated by the computer algorithms also correlated highly with the average of observer measurements (r > or = 0.93). We have developed computerized techniques for the measurement of mesothelioma tumor thickness in CT scans. These techniques achieved varying levels of agreement with measurements made by human observers. 相似文献
62.
Genetic diversity among community methicillin-resistant Staphylococcus aureus strains causing outpatient infections in Australia 下载免费PDF全文
Coombs GW Nimmo GR Bell JM Huygens F O'Brien FG Malkowski MJ Pearson JC Stephens AJ Giffard PM;Australian Group for Antimicrobial Resistance 《Journal of clinical microbiology》2004,42(10):4735-4743
Increasing reports of the appearance of novel nonmultiresistant methicillin-resistant Staphylococcus aureus MRSA (MRSA) strains in the community and of the spread of hospital MRSA strains into the community are cause for public health concern. We conducted two national surveys of unique isolates of S. aureus from clinical specimens collected from nonhospitalized patients commencing in 2000 and 2002, respectively. A total of 11.7% of 2,498 isolates from 2000 and 15.4% of 2,486 isolates from 2002 were MRSA. Approximately 54% of the MRSA isolates were nonmultiresistant (resistant to less than three of nine antibiotics) in both surveys. The majority of multiresistant MRSA isolates in both surveys belonged to two strains (strains AUS-2 and AUS-3), as determined by pulsed-field gel electrophoresis (PFGE) and resistogram typing. The 3 AUS-2 isolates and 10 of the 11 AUS-3 isolates selected for multilocus sequence typing (MLST) and staphylococcal chromosomal cassette mec (SCCmec) analysis were ST239-MRSA-III (where ST is the sequence type) and thus belonged to the same clone as the eastern Australian MRSA strain of the 1980s, which spread internationally. Four predominant clones of novel nonmultiresistant MRSA were identified by PFGE, MLST, and SCCmec analysis: ST22-MRSA-IV (strain EMRSA-15), ST1-MRSA-IV (strain WA-1), ST30-MRSA-IV (strain SWP), and ST93-MRSA-IV (strain Queensland). The last three clones are associated with community acquisition. A total of 14 STs were identified in the surveys, including six unique clones of novel nonmultiresistant MRSA, namely, STs 73, 93, 129, 75, and 80slv and a new ST. SCCmec types IV and V were present in diverse genetic backgrounds. These findings provide support for the acquisition of SCCmec by multiple lineages of S. aureus. They also confirm that both hospital and community strains of MRSA are now common in nonhospitalized patients throughout Australia. 相似文献
63.
J. Stephen Bamforth Clifford Fabian Geoffrey Machin Louis Honore 《American journal of medical genetics. Part A》1992,43(5):780-784
We describe a female infant with apparent Poland anomaly (PA) and limb body wall defect. Analysis of the defects suggest that a disruption of the lateral embryonic plate mesoderm may have been responsible for the observed lesions. Because of the overlap of this case with PA, we re-examined previous reports of this syndrome. We think that the lesions could be equally well explained as a mesodermal disruption, and point out a previously unrecognised discrepancy between sex and affected side in sporadic PA and inherited PA which supports this view. © 1992 Wiley-Liss, Inc. 相似文献
64.
Green Steven; Fishel Simon; Hall Jenny; Hunter Alison; Fleming Steven; Hobson Geoffrey; Roe Heather; Dowell Ken; Thornton Simon; Klentzeris Lucas 《Human reproduction (Oxford, England)》1995,10(6):1430-1434
Utilizing real-time computer image analysis, individual spermatozoawere selected using microaspiration. Selection criteria werebased on potential hyperactivation motility characteristics;the amplitude of lateral head displacement >7.5 µm,curvilinear velocity >70 µm/s and linearity of <30%.For this pilot study, 16 patients (eight in each group) wererecruited. Using subzonal insemination (SUZI), up to five (mean= 4.4 ± 0.3) spermatozoa selected using computer-imagesperm selection (CISS) were microinjected, or up to 15 (mean= 12.8 ± 1.3 SD) unselected spermatozoa. In the groupwhich utilized CISS, 28 out of 49 (57%) oocytes were fertilizedcompared with 13 out of 52 (25%) utilizing conventional SUZI(P < 0.04); polyspermy was 20% (n = 10) and 2% (n = 1) respectively.CISS with SUZI showed increased efficiency in achieving fertilizationand is a novel approach to studying individual sperm functionin a sperm egg bioassay where gamete ratios are close to unity. 相似文献
65.
66.
Williams GC McGregor HA King D Nelson CC Glasgow RE 《Patient education and counseling》2005,57(1):39-45
There is considerable variation in care provided to patients with diabetes related to metabolic control, preventive services, and degree of patient-centered support. This study evaluates the relation of self-determination theory (SDT) constructs of clinician autonomy support, and patient competence to glycemic control, depressive symptoms, and patient satisfaction from baseline surveys of 634 patients of 31 Colorado primary care physicians participating in a program to improve diabetes care. Spearman correlations of autonomy support from one's clinician with patient competence, HbA1c, depressive symptoms and satisfaction were significant (R = -0.11 to 0.55, P < 0.005). Structural equation modeling demonstrated that autonomy support was significantly related to perceived competence, depressive symptoms, patient satisfaction, and indirectly to glycemic control. Perceived competence was significantly related to depressive symptoms, patient satisfaction and glycemic control. Further, the motivation constructs from SDT accounted for 5% of the variance in glycemic control, 8% of the variance in depression, and 42% of the variance in patient satisfaction. Quality improvement efforts need to pay greater attention to patient competence, satisfaction, and depression, in addition to glycemic control. Clinician autonomy support was found to be reliably measured and moderately correlated with psychosocial and biologic outcomes related to diabetes self-management. These results suggest training clinicians to increase their support of patient autonomy may be one important avenue to improve diabetes outcomes. 相似文献
67.
Martin E. Weinand Namath Hussain David M. Labiner Geoffrey L. Ahern 《Pathophysiology》2006,13(4):233-236
This study was performed to test the hypothesis that, in human temporal lobe epilepsy, electrocorticographic time factors involved in the ictal EEG to clinical ictal transition (electrocorticographic to clinical seizure onset time, ECOT) and the interhemispheric propagation of epileptic activity (interhemispheric propagation time, IHPT), which are independently correlated with temporal lobe epileptogenicity and predictive of seizure-free outcome following temporal lobectomy, are correlated with one another in a quantitative fashion. A series of 37 patients with medically intractable temporal lobe seizures was studied with long-term subdural videoelectroencephalographic monitoring. Temporal lobe seizure interhemispheric propagation time (IHPT) was found to be a negative, exponential function of electrocorticographic to clinical seizure onset time (ECOT) (f(x) = 8.201 × 10−0.016x, r = 0.347, d.f. = 35, t = 2.19, p < 0.05, where f(x) = IHPT and x = ECOT). A small increase in ECOT was associated with a substantial decrease in IHPT and vice versa. The results suggest the electrophysiological time factor, ECOT, involved in the transition from ictal EEG seizure onset to clinical seizure onset, may determine the speed of interhemispheric propagation of established epileptic activity. The results suggest the interesting hypothesis that, in human temporal lobe epilepsy and, perhaps, under non-pathological circumstances, the human temporal lobe might possess a “time-labeling” function amenable to quantitative analysis. 相似文献
68.
Louis Journeau Marc-Antoine Pistorius Ulrique Michon-Pasturel Marc Lambert Francois-Xavier Lapébie Alessandra Bura-Riviere Philippe de Faucal Patrick Jego Quentin Didier Cécile Durant Geoffrey Urbanski Baptiste Hervier Claire Toquet Christian Agard Olivier Espitia 《Autoimmunity reviews》2019,18(5):476-483
69.
Stoltenberg SF Twitchell GR Hanna GL Cook EH Fitzgerald HE Zucker RA Little KY 《American journal of medical genetics》2002,114(2):230-234
A functional polymorphism in the regulatory region of the serotonin transporter gene (5-HTTLPR) is considered to be a plausible candidate gene for anxiety-related personality traits and for alcoholism. Empirical support for the association between 5-HTTLPR and psychological traits has been somewhat inconsistent; however, observations of the functional dominance of the low-activity s-allele over the l-allele have been more consistent. When studying the influence of particular genes on psychological traits, it seems useful also to assess more biological intermediate traits that may mediate the effects of those genes on the traits of interest. The present study examined relationships between 5-HTTLPR genotype, whole blood serotonin (5-HT) level, and platelet 5-HT binding in 150 Caucasian subjects from 50 biological families. Individuals with the s-allele had lower average platelet 5-HT binding availability than those with the l/l genotype (P<0.025). Whole blood 5-HT level was not associated with 5-HTTLPR genotype. In adult men, those with the s-allele had higher mean scores on the NEO-FFI personality trait of openness than did those with the l/l genotype (P=0.002). The effect was not statistically significant in women (P=0.42), although it was in the same direction. Our findings do not support an association of 5-HTTLPR genotype with alcoholism diagnosis, alcoholism subtype, or the personality trait of neuroticism. The results of this pilot study suggest that further work should examine the mediation of the genetic effects on personality traits by biochemical measures and their moderation by gender. 相似文献
70.
Holly James Westervelt Jessica Somerville Ruffolo Geoffrey Tremont 《Archives of clinical neuropsychology》2005,20(6):761-769
The relationship between odor identification and cognition has not been previously well characterized. The neuroanatomy of the olfactory system and the frequent finding of olfactory dysfunction in neurodegenerative diseases suggest a likely relationship between odor identification and memory, language, and executive functioning, though previous studies have often failed to demonstrate the expected relationship. The current study examined this relationship in across a continuum of ability levels (N=100). Strongest correlations were found between odor identification and language, most aspects of memory, and a measure of general cognitive functioning. Significant but more modest correlations were seen between odor identification and attention, motor, visuospatial, and executive functions. A regression analysis revealed language as the only significant predictor of olfactory performance. These findings suggest that odor identification is most closely associated with other measures of temporo-limbic functioning. The implications of these findings, particularly in consideration of the assessment of older adults, are discussed. 相似文献