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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.
《Journal of the American Medical Directors Association》2020,21(12):1968-1972.e2
ObjectivesVitamin D deficiency is prevalent among older adults. We aimed to study whether residential greenness could alter serum 25(OH)D concentrations as a possible mechanism of residential greenness's positive health effects.DesignA longitudinal cohort study.Setting and ParticipantsWe included older adults aged ≥65 years from the Chinese Longitudinal Healthy Longevity Survey (CLHLS) with follow-up between 2012 and 2014.MethodsWe measured residential greenness by calculating annual average Normalized Difference Vegetation Index (NDVI) in a 500 m radius by using satellite images around each participant's residential address. Serum 25-hydroxyvitamin D (25(OH)D) concentration was dichotomized into 2 categories: nondeficiency (≥50 nmol/L) and deficiency (<50 nmol/L). We used the generalized estimating equation to examine the relationship between annual average NDVI and serum 25(OH)D.ResultsWe included 1336 participants in our analysis. The annual average NDVI was 0.49, and mean serum 25(OH)D was 43 nmol/L at baseline. Each 0.1-unit increase in annual average NDVI was associated with a 13% higher odds of vitamin D nondeficiency [95% confidence interval (CI): 1.01, 1.26]. The association was stronger among men [odds ratio (OR): 1.17, 95% CI: 1.02, 1.35] than women (OR: 1.08, 95% CI: 0.91, 1.29) and also stronger among those who were free of activities of daily living (ADL) disability at baseline (OR: 1.12, 95% CI: 1.00, 1.25). During the follow-up period, the participants who lived in greener areas were more likely to have an improved, rather than stable or deteriorated, vitamin D status (OR: 1.94, 95% CI: 1.51, 2.51).Conclusions and ImplicationsOur study suggests that higher levels of residential greenness are associated with higher serum 25(OH)D concentrations, which has implications for prevention of vitamin D deficiency among older adults. 相似文献
3.
Kudo T Kawase M Kawada S Kurosawa H Koyanagi H Takeuchi Y Hosoda Y Wanibuchi Y 《Artificial organs》1999,23(2):199-203
Anticoagulant therapy after cardiac valve replacement was evaluated retrospectively in 1,200 patients attending 8 cardiac surgery clinics in the Tokyo area as part of the Tokyo Area Study on Anticoagulation After Cardiac Valve Replacement Using PT-INR (TAS). A prospective trial is also in progress and will be reported later. The prothrombin time international normalized ratio (PT-INR) was determined at the time of thromboembolic and bleeding complications in 1,200 patients. During the 5 year study period, thromboembolisms occurred in 21 patients, and bleeding complications occurred in 15 patients. In 71% of patients with thromboembolism and 47% of those with bleeding complications, the PT-INR was within the range of 1.6 to 2.8, which is the accepted therapeutic range in Japan. Therefore, the correct PT-INR therapeutic range for Japanese patients with mechanical heart valves needs to be reexamined, and data from the prospective TAS trial that is currently underway will be used for this purpose. 相似文献
4.
国际敏感指数在血浆凝血酶原时间测定中的应用 总被引:1,自引:0,他引:1
目的 :分析在测定 PT- INR实验过程中建立实验室敏感指数 (L ocal ISI)值的方法和必要性。方法 :在 CA- 15 0 0全自动凝血仪上使用 INR定标血浆建立 INR标准曲线 ,并做回归分析 ,计算出 L ocal ISI值 ,并利用 Dade- behring公司产品 Thromborel S凝血活酶试剂 ISI值和 L ocal ISI值分别测定 4 3例正常对照组和 2 0例长期口服抗凝药物治疗患者的凝血酶原时间 PT- INR,对两组结果进行统计处理。结果 :经校正本实验所用 Dade- behring公司产品 Throm borel S凝血活酶试剂 L ocal ISI值为 1.10 ,高于厂家提供的 ISI值。两组受试者利用 L ocal ISI值和 ISI值测定所得 PT- INR值差异有极显著性 (P<0 .0 1) L ocal ISI值组明显高于 ISI值组。结论 :直接利用试剂厂家标定的 ISI值进行 PT- INR值测定可能造成误差 ,仍应用 PT- INR定标血浆仪器上进行校正。利用实验室敏感指数 (L ocal ISI)值测定 PT- INR具有可信性 ,可应用于口服抗凝药物治疗监测 相似文献
5.
The international normalized ratio (INR): What reagent,what instrument? The assessment of the agreement between INR values according to different reagent/instrument combinations
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7.
Pia Bükmann Larsen Elin Storjord Åsne Bakke Tone Bukve Mikael Christensen Joakim Eikeland 《Scandinavian journal of clinical and laboratory investigation》2017,77(2):115-121
Regular measurement of prothrombin time as an international normalized ratio PT (INR) is mandatory for optimal and safe use of warfarin. Scandinavian evaluation of laboratory equipment for primary health care (SKUP) evaluated the microINR portable coagulometer (microINR®) (iLine Microsystems S.L., Spain) for measurement of PT (INR). Analytical quality and user-friendliness were evaluated under optimal conditions at an accredited hospital laboratory and at two primary health care centres (PHCCs). Patients were recruited at the outpatient clinic of the Laboratory of Medical Biochemistry, St Olav’s University Hospital, Trondheim, Norway (n?=?98) and from two PHCCs (n?=?88). Venous blood samples were analyzed under optimal conditions on the STA-R®Evolution with STA-SPA?+?reagent (Stago, France) (Owren method), and the results were compared to capillary measurements on the microINR®. The imprecision of the microINR® was 6% (90% CI: 5.3–7.0%) and 6.3% (90% CI: 5.1–8.3) in the outpatient clinic and PHCC2, respectively for INR ≥2.5. The microINR® did not meet the SKUP quality requirement for imprecision ≤5.0%. For INR <2.5 at PHCC2 and at both levels in PHCC1, CV% was ≤5.0. The accuracy fulfilled the SKUP quality goal in both outpatient clinic and PHCCs. User-friendliness of the operation manual was rated as intermediate, defined by SKUP as neutral ratings assessed as neither good nor bad. Operation facilities was rated unsatisfactory, and time factors satisfactory. In conclusion, quality requirements for imprecision were not met. The SKUP criteria for accuracy was fulfilled both at the hospital and at the PHCCs. The user-friendliness was rated intermediate. 相似文献
8.
9.
《Revista portuguesa de cardiologia》2014,33(7-8):397-401
Introduction and ObjectivesWith the advent of new oral anticoagulants that do not require regular laboratory control but are significantly more expensive, there has been renewed interest in the quality of the classic agents and the monitoring of patients taking them. We set out to analyze time in therapeutic range of patients under oral anticoagulation monitored in our health unit, to determine whether primary care monitoring is comparable to that in anticoagulation clinics. At the same time, we aimed to ascertain whether there was any association between the dosing method (unit protocol vs. computer‐assisted) and the time in therapeutic range achieved.Methods We analyzed all INR values determined in our health unit during the first six months of 2012, using Excel 2007 and SPSS version 17.0, and applying the Student's t test for a level of significance of 0.05.ResultsAll INR assessments during the first six months of 2012 were recorded, a total of 320 tests; mean patient age was 69.9±11.25 years, 63% male. Dose adjustments were made according to the unit protocol in 77% of cases. Atrial fibrillation was the most prevalent indication. Most values (65.3%) were within the target therapeutic range; 24.1% were subtherapeutic and 10.6% supratherapeutic. Computer‐assisted dosing achieved better control than the protocol (72.5% vs. 62.9%), without statistical significance.ConclusionsPrimary care monitoring of oral anticoagulation appears to be comparable to that in anticoagulation clinics, while affording better access and cost reductions. 相似文献
10.
Arman Qamar Muthiah Vaduganathan Norton J. Greenberger Robert P. Giugliano 《Journal of the American College of Cardiology》2018,71(19):2162-2175
Patients with liver disease are at increased risks of both thrombotic and bleeding complications. Many have atrial fibrillation (AF) or venous thromboembolism (VTE) necessitating oral anticoagulant agents (OACs). Recent evidence has contradicted the assumption that patients with liver disease are “auto-anticoagulated” and thus protected from thrombotic events. Warfarin and non–vitamin K–antagonist OACs have been shown to reduce thrombotic events safely in patients with either AF or VTE. However, patients with liver disease have largely been excluded from trials of OACs. Because all currently approved OACs undergo metabolism in the liver, hepatic dysfunction may cause increased bleeding. Thus, the optimal anticoagulation strategy for patients with AF or VTE who have liver disease remains unclear. This review discusses pharmacokinetic and clinical studies evaluating the efficacy and safety of OACs in patients with liver disease and provides a practical, clinically oriented approach to the management of OAC therapy in this population. 相似文献