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53.
生理影像是功能性医学影像的一个重要分支,也是临床医学工程的一个极其重要的研究和应用领域。多年来,作者及其研究生与临床医务人员相结合,在电生理影像和热生理影像的信息获取和数字化处理技术方面进行了大量及深入的研究,提出了一种体内热估计(ITE)新技术。本文重点介绍热生理影像信息在妇女乳腺癌诊断中的应用。通过对约五千例妇女乳腺病筛选的结果,表明了生理影像信息处理及ITE技术在临床医学上的应用价值。 相似文献
54.
Margaret Sullivan Pepe Ziding Feng Gary Longton Joseph Koopmeiners 《Statistics in medicine》2009,28(5):762-779
Development of a disease screening biomarker involves several phases. In phase 2 its sensitivity and specificity is compared with established thresholds for minimally acceptable performance. Since we anticipate that most candidate markers will not prove to be useful and availability of specimens and funding is limited, early termination of a study is appropriate, if accumulating data indicate that the marker is inadequate. Yet, for markers that complete phase 2, we seek estimates of sensitivity and specificity to proceed with the design of subsequent phase 3 studies. We suggest early stopping criteria and estimation procedures that adjust for bias caused by the early termination option. An important aspect of our approach is to focus on properties of estimates conditional on reaching full study enrollment. We propose the conditional‐UMVUE and contrast it with other estimates, including naïve estimators, the well‐studied unconditional‐UMVUE and the mean and median Whitehead‐adjusted estimators. The conditional‐UMVUE appears to be a very good choice. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
55.
OBJECTIVE: Screening colonoscopy has been shown to reduce mortality and cancer stage in hereditary nonpolyposis colorectal cancer (HNPCC) individuals. However, the benefit of screening in intermediate risk groups is unknown. The most recent national guidelines have recommended a reduction of screening frequency for the intermediate risk group. Therefore, this study aims to compare the results of colonoscopic screening in HNPCC and intermediate risk groups and assess the effect of the most recent screening protocol recommendations. METHOD: A total of 244 individuals; 108 from HNPCC families (28 mismatch repair gene carriers) and 136 from intermediate risk families were referred for regular colonoscopic screening by the Regional Genetics Service. Findings from 417 colonoscopies performed between 1992 and 2003 were evaluated. RESULTS: A total of three cancers, 39 adenomas and 41 hyperplastic polyps were found in the HNPCC group compared with one cancer, 22 adenomas and 19 hyperplasic polyps in the intermediate risk group. If the recent screening guidelines for the intermediate group were applied, then 89 (44%) fewer colonoscopies would have been performed. Although no cancers would have been missed, six adenomas (mean size = 5.7 mm, range 2-10 mm) with two graded as severely dysplasic and six hyperplastic polyps would not have been detected. CONCLUSION: The detection rate and distribution of adenomas were similar in both groups. If the new colonoscopic screening recommendations for the intermediate risk group had been applied, a small number of significant lesions would have been missed. 相似文献
56.
Objective. The objective of our paper is to show that the spatio-temporal image correlation (STIC) and tomographic ultrasound imaging (TUI) is very convenient and helpful for the fetal screening of complex congenital heart defects (CHD).
Methods. Ultrasound examinations were performed using a Voluson 730 EXPERT or PRO system (GE Medical system, Kretztechnik, Zipf, Austria), and the transabdominal probe (RAB 4-8 MHz or 1-5 MHz) was used to acquire the STIC volumes. Various complex CHD including heterotaxia, ventricular septal defect (VSD), atrio-ventricular septal defect (AVSD), tetralogy of fallot (TOF), transposition of great artery (TGA), hypoplastic left heart syndrome (HLHS) were examined between 20 weeks and 35 weeks. After routine cardiac screening and examination by two-dimensional ultrasound, three- and four-dimensional ultrasound were performed by gray-scaled and color flow mapping. After the examination detailed analysis of CHD were performed by STIC and TUI.
Results. In the case of heterotaxia, STIC and TUI was useful for the detection of stomach and cardiac apex in the different slices. In the case of VSD and AVSD, they were useful for the exact determination of septal defect location. In the cases of TOF, TGA and HLHS, they were helpful for observation of outflow tract and exact diagnosis.
Conclusion. In the screening of complex CHD including heterotaxia, VSD, AVSD, TOF, TGA and HLHS, STIC is very useful and powerful tool. 相似文献
Methods. Ultrasound examinations were performed using a Voluson 730 EXPERT or PRO system (GE Medical system, Kretztechnik, Zipf, Austria), and the transabdominal probe (RAB 4-8 MHz or 1-5 MHz) was used to acquire the STIC volumes. Various complex CHD including heterotaxia, ventricular septal defect (VSD), atrio-ventricular septal defect (AVSD), tetralogy of fallot (TOF), transposition of great artery (TGA), hypoplastic left heart syndrome (HLHS) were examined between 20 weeks and 35 weeks. After routine cardiac screening and examination by two-dimensional ultrasound, three- and four-dimensional ultrasound were performed by gray-scaled and color flow mapping. After the examination detailed analysis of CHD were performed by STIC and TUI.
Results. In the case of heterotaxia, STIC and TUI was useful for the detection of stomach and cardiac apex in the different slices. In the case of VSD and AVSD, they were useful for the exact determination of septal defect location. In the cases of TOF, TGA and HLHS, they were helpful for observation of outflow tract and exact diagnosis.
Conclusion. In the screening of complex CHD including heterotaxia, VSD, AVSD, TOF, TGA and HLHS, STIC is very useful and powerful tool. 相似文献
57.
Katherine Patterson Corinna Young Steven Paul Woods Ofilio Vigil Igor Grant J. Hampton Atkinson 《International journal of methods in psychiatric research》2006,15(2):75-82
Major Depressive Disorder (MDD) is among the most prevalent but underdiagnosed psychiatric disorders in persons with HIV infection. Given the known adverse impact of comorbid MDD on HIV disease progression and health‐related quality of life, it is important both for research and for efficient, effective clinical care, to validate existing screening measures that may discriminate between MDD and the somatic symptoms of HIV (such as fatigue). In the current study, we evaluated the concurrent predictive validity of the Profile of Mood States (POMS) Depression‐Dejection scale in detecting current MDD in 310 persons with HIV infection. The Structured Clinical Interview for DSM‐IV (SCID) diagnosis of MDD and the Cognitive‐Affective scale from the Beck Depression Inventory (BDI‐CA) served as comparative diagnostic and severity measures of depression, respectively. Results demonstrated that the POMS Depression‐Dejection scale accurately classified persons with and without MDD SCID diagnoses, with an overall hit rate of 80%, sensitivity of 55%, specificity of 84%, and negative predictive power of 91% using a recommended cutpoint of 1.5 standard deviations above the normative mean. Moreover, the POMS performed comparably to the BDI‐CA in classifying MDD. Findings support the predictive validity of the POMS Depression‐Dejection scale as a screening instrument for MDD in persons with HIV disease. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
58.
Tomotaka Sobue Takaichiro Suzuki Tsuguo Naruke The Japanese Lung Cancer Screening Research Group 《Cancer science》1992,83(5):424-430
A case-control study to evaluate the efficacy of lung cancer screening conducted by us showed that lung cancer screening may reduce the mortality of the disease up to 28%. Assuming this efficacy is unbiased, and that the screening rate is 51.6%, which was observed in the control group in the above study, the number of lung cancer deaths prevented by screening in the study period was calculated to be 47 for males and females combined. In the same study population, screen-detected lung cancer patients (N = 207) in the same study period were followed and the 7-year survival rate (46.9%) was compared to the 5-year survival rate (11.3%) obtained by the Osaka Cancer Registry, in which screen-detected lung cancer patients were only 1.8%. The number of lung cancer deaths prevented by screening, estimated by the difference in the above two survival rates, was 74 (95% confidence interval; 55–93). The number of lung cancer deaths prevented by screening estimated from the case-control study was significantly lower than that estimated from the survival analysis. This indicates that the efficacy of lung cancer screening estimated by the case-control study was within the range that could be explained by the actual long-term survivors among the screen-detected patients in the study population. 相似文献
59.
Laura J. Solomon Ph.D. Ruth M. Mickey Ph.D. C.J. Rairikar M.A. John K. Worden Ph.D. Brian S. Flynn Sc.D. 《Preventive medicine》1998,27(6):781-786
Background.This study prospectively examined rates of adherence to mammography, clinical breast examination (CBE), and breast self-examination (BSE) in a cohort of women over 3 years to determine whether participation in BSE influenced participation in the other two screening modalities.Methods.Women ages 51 and older (n= 450) who attended a small group educational session to learn BSE and to hear about CBE and mammography guidelines were assessed annually by telephone for 3 consecutive years to determine their subsequent breast cancer screening behavior.Results.Annual CBE and mammography screening are highly positively associated. Regular performance of BSE has a modest positive association with both CBE and mammography adherence over time.Conclusions.Women who perform BSE regularly over time may be more likely to adhere to the other breast cancer screening guidelines. 相似文献
60.
M. NISHI H. MIYAKE T. TAKEDA N. TAKASUGI J. HANAI T. KAWAI 《Acta paediatrica (Oslo, Norway : 1992)》1991,80(8-9):812-817
ABSTRACT. On the basis of epidemiological data and medical costs for patients with neuroblastoma, we have calculated the cost of mass screening for neuroblastoma with high performance liquid chromatography (HPLC) compared to the cost when it is not performed. If the sensitivity of the mass screening is 80 % and 22 000 infants are screened annually the cost will be 27809000 yen ($191800). If mass screening is not performed, the cost will be 28 446 000 yen ($196 200). The difference in cost (637 000 yen or $4 400) is fairly small. If the sensitivity is 75 % and 16 500 infants are screened, the difference is also small (174000 yen or $1 200). Therefore, mass screening with the HPLC method will not be an undue financial burden. But re-screening at an older age will be done with less financially favorable results, considering that the sensitivity may not be as high as that of the first screening and that mothers are somewhat reluctant about re-screening. The balance of the cost of mass screening by qualitative methods may also be less favorable, since the detection rate is low. 相似文献