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1.
《Diagnostic and interventional imaging》2020,101(9):555-564
PurposeThe purpose of this study was to determine whether computed tomography (CT)-based machine learning of radiomics features could help distinguish autoimmune pancreatitis (AIP) from pancreatic ductal adenocarcinoma (PDAC).Materials and MethodsEighty-nine patients with AIP (65 men, 24 women; mean age, 59.7 ± 13.9 [SD] years; range: 21–83 years) and 93 patients with PDAC (68 men, 25 women; mean age, 60.1 ± 12.3 [SD] years; range: 36–86 years) were retrospectively included. All patients had dedicated dual-phase pancreatic protocol CT between 2004 and 2018. Thin-slice images (0.75/0.5 mm thickness/increment) were compared with thick-slices images (3 or 5 mm thickness/increment). Pancreatic regions involved by PDAC or AIP (areas of enlargement, altered enhancement, effacement of pancreatic duct) as well as uninvolved parenchyma were segmented as three-dimensional volumes. Four hundred and thirty-one radiomics features were extracted and a random forest was used to distinguish AIP from PDAC. CT data of 60 AIP and 60 PDAC patients were used for training and those of 29 AIP and 33 PDAC independent patients were used for testing.ResultsThe pancreas was diffusely involved in 37 (37/89; 41.6%) patients with AIP and not diffusely in 52 (52/89; 58.4%) patients. Using machine learning, 95.2% (59/62; 95% confidence interval [CI]: 89.8–100%), 83.9% (52:67; 95% CI: 74.7–93.0%) and 77.4% (48/62; 95% CI: 67.0–87.8%) of the 62 test patients were correctly classified as either having PDAC or AIP with thin-slice venous phase, thin-slice arterial phase, and thick-slice venous phase CT, respectively. Three of the 29 patients with AIP (3/29; 10.3%) were incorrectly classified as having PDAC but all 33 patients with PDAC (33/33; 100%) were correctly classified with thin-slice venous phase with 89.7% sensitivity (26/29; 95% CI: 78.6–100%) and 100% specificity (33/33; 95% CI: 93–100%) for the diagnosis of AIP, 95.2% accuracy (59/62; 95% CI: 89.8–100%) and area under the curve of 0.975 (95% CI: 0.936–1.0).ConclusionsRadiomic features help differentiate AIP from PDAC with an overall accuracy of 95.2%. 相似文献
2.
Conall T. Morgan Brigitte Mueller Varsha Thakur Vitor Guerra Callaghan Jull Luc Mertens Mark Friedberg Fraser Golding Mike Seed Steven E.S. Miner Edgar T. Jaeggi Cedric Manlhiot Lynne E. Nield 《The Canadian journal of cardiology》2019,35(4):453-461
Background
The purpose of the study was to evaluate the association between fetal echocardiographic measurements and the need for intervention (primary coarctation repair, staged coarctation repair, or catheter intervention) in prenatally diagnosed coarctation of the aorta.Methods
A single-centre retrospective cohort study (2005-2015) of 107 fetuses diagnosed with suspected coarctation of the aorta in the setting of an apex-forming left ventricle and antegrade flow across the mitral and aortic valves.Results
Median gestational age at diagnosis was 32 weeks (interquartile range, 23-35 weeks). Fifty-six (52%) did not require any neonatal intervention, 51 patients (48%) underwent a biventricular repair. In univariable analysis, an increase in ascending aorta (AAo) peak Doppler flow velocity (odds ratio [OR], 1.40 [95% confidence interval [CI], 1.05-1.91] per 20 cm/s; P = 0.03) was associated with intervention. No intervention was associated with larger isthmus size (OR, 0.23; P < 0.001), transverse arch diameter (OR, 0.23; P < 0.001), and aortic (OR, 0.72; P = 0.02), mitral (OR, 0.58; P = 0.001), and AAo (OR, 0.53; P < 0.001) z-scores. In multivariable analysis, higher peak AAo Doppler (OR, 2.51 [95% CI, 1.54-4.58] per 20 cm/s; P = 0.001) and younger gestational age at diagnosis (OR, 0.81 [95% CI, 0.70-0.93] per week; P = 0.005) were associated with intervention, whereas a higher AAo z-score (OR, 0.65 [95% CI, 0.43-0.94] per z; P = 0.029) and transverse arch dimension (OR, 0.44 [95% CI, 0.18-0.97]; P = 0.05) decreased the risk of intervention.Conclusions
In prenatally suspected coarctation, the variables associated with intervention comprised smaller AAo and transverse arch size, earlier gestational age at diagnosis, and the additional finding of a higher peak AAo Doppler. 相似文献3.
《Cancer cell》2020,37(1):123-134.e5
4.
5.
6.
Marvin Rubenstein Robert Saffrin Michael Shaw Sergey Muchnik Patrick Guinan 《The Prostate》1995,27(3):148-153
Orthotopic placement of in vitro propagated Dunning R3327 AT-3 tumor cells resulted in a greater percentage of tumor takes and a two-fold shift in the exponential growth curve compared to flank implantation. The orthotopic tumor appeared to disseminate preferentially to regional lymph nodes, rather than to the lungs which is characteristic of flank tumors. The results suggest an important role of stromal-epithelial interactions in the growth of this tumor. © 1995 Wiley-Liss, Inc. 相似文献
7.
ltiswellknownthattheskinofextensivelyburnedcasesthemselvesisinsufficienttoprovidecoverageforwounds.Thoughallogeneicskincancoverthewoundstemporari1y,itwillberejectedwithin2-3weeks.Thiscanthreatenthepatient'slifeifthereisnoenoughautogenousskintoreplacetherejectedoneontime.GreenetalL1]reportedthattheburnwoundsofpatientswithextensiveburnscouldbetreatedbytransplantingepidermalautograftsafterautologousepidermalcellsmulti-plyforthousandsoftimesinvltrowithinashortperiodoftime-Butittakesatleast2-3weeks… 相似文献
8.
Zusammenfassung
Eine neu aufgetretene Dyspnoesymptomatik und eine symmetrische, apikal betonte retikulonodul?re Zeichnungsvermehrung im R?ntgen-Thorax
bei jungen rauchenden Erwachsenen müssen an das seltene Krankheitsbild der pulmonalen Histiocytosis X denken lassen. Klinischer
Befund, laborchemische- und Lungenfunktionsuntersuchungen zeigen unspezifische Befunde. Neue radiologische Verfahren wie die
hochaufl?sende Computertomographie (HRCT) leisten bei gezielter Indikationsstellung eine entscheidende differentialdiagnostische
Hilfestellung.
Dieser Fall verdeutlicht die M?glichkeit einer Diagnosesicherung durch transbronchiale Biopsien unter Verzicht auf offene
Lungenbiopsien. Eine ambulante Diagnostik war m?glich, das h?here Risiko eines operativen Eingriffes konnte vermieden werden.
Die Indikation zur Therapie ist nicht gesichert und wird daher durch den Grad der subjektiven bzw. funktionellen Einschr?nkung
sowie den Verlauf bestimmt. 相似文献
9.
Tsutomu Ogata Peter Goodfellow Christine Petit Pierre Maroteaux Nobutake Matsuo 《American journal of medical genetics. Part A》1993,45(1):101-104
This is a follow-up report on a male patient with a 46, Y, r(X) karyotype. Although he had no clinico-radiological features of X-linked recessive chondrodysplasia punctata (CDPX1), molecular studies revealed an Xp terminal deletion involving the putative region for the CDPX1 locus (PABX-DXS31). We suspect that the absence of CDPX1 may be attributable to the nature of the disease and the extreme short stature of the patient (mean – 5.6 S.D.). © 1993 Wiley-Liss, Inc. 相似文献
10.
In a cohort of 3383 men aged 53 to 74 in the Copenhagen Male Study we investigated the association between ischaemic heart disease (IHD) and the Lewis blood group, assigned to chromosome 19. Among men with the Le(a-b-) phenotype, 8% had a history of non-fatal myocardial infarction, among others the frequency was 4%. The corresponding odds ratio was (95% confidence interval: CI) 1.9 (1.2-3.0) P < 0.01, men with Le(a-b-) had a risk-factor profile and pattern of disease resembling that of Reaven's syndrome X. In a subsequent prospective study 343 men with arteriosclerotic stigmas were excluded. The men had their morbidity and mortality recorded over the next 4 years. One-hundred-and-one men suffered IHD; 26 dying from IHD. In total 162 men died. Men with Le(a-b-) had an increased risk of death from IHD compared with others. Adjusted for age, relative risk (RR) (95% CI) was: 4.4 (1.9-10.3), P < 0.001, and for all causes of mortality: RR = 1.6 (1.0-2.6), P < 0.05. Men with the Le(a-b-) phenotype had an increased risk of an IHD event compared to men with other phenotypes (RR = 1.6 (0.9-2.8), P = 0.10) and a significantly higher IHD case fatality rate (RR = 2.8 (1.5-5.2), P = 0.01). The finding that the Le(a-b-) phenotype is a genetic marker of IHD risk may have implications in terms of prevention. The Le(a-b-) phenotype may also contribute to providing an explanation for the substantial ethnic differences found in the incidence of IHD. The similar risk-factor profile and pattern of disease found between Le(a-b-) men and individuals with Reaven's syndrome X is hypothesized to be due to a close genetic relationship on chromosome 19. 相似文献