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961.
962.
963.
TL Garibova EA Val''dman TA Voronina VA Kra?neva 《Canadian Metallurgical Quarterly》1998,125(5):538-540
PURPOSE: To test whether physician's diagnostic inferences can be improved by communicating information using natural frequencies instead of probabilities. Whereas probabilities and relative frequencies are normalized with respect to disease base rates, natural frequencies are not normalized. METHOD: The authors asked 48 physicians in Munich and Düsseldorf to determine the positive predictive values (PPVs) of four diagnostic tests. Information presented in the four problems appeared either as probabilities (the traditional way) or as natural frequencies. RESULTS: When the information was presented as probabilities, the physicians correctly estimated the PPVs in only 10% of cases. When the same information was presented as natural frequencies, that percentage increased to 46%. CONCLUSION: Representing information in natural frequencies is a fast and effective way of facilitating diagnosis insight, which in turn helps physicians to better communicate risks to patients, and patients to better understand these risks. 相似文献
964.
Partial Fourier (PF) methods take advantage of data symmetry to allow for either faster image acquisition or increased image resolution. Faster acquisition and increased spatial resolution are advantageous for fMRI because of increased temporal resolution and/or reduced partial volume effects, respectively. Standard PF methods, which use a phase reference obtained from a low resolution image, are adequate for the reconstruction of time-stationary images acquired using either spin echoes or short TE gradient echoes. In fMRI, however, multiple images are acquired using long TE gradient echoes, which introduces possible phase drifts in the fMRI data and high spatial frequencies in the phase reference. This work investigates several techniques developed to reconstruct fMRI data obtained with PF acquisitions. PF methods that account for both high-frequency spatial variations and time-dependent drifts in the phase reference are discussed and are quantitatively evaluated using receiver operator characteristic curve analysis. 相似文献
965.
MD Prados CB Scott M Rotman P Rubin K Murray W Sause S Asbell R Comis W Curran J Nelson RL Davis VA Levin K Lamborn TL Phillips 《Canadian Metallurgical Quarterly》1998,40(3):653-659
PURPOSE: To examine the effect of treatment using Bromodeoxyuridine (BrdU) during radiation therapy on malignant glioma patient survival by comparing historical survival data from several large clinical trials. METHODS: A retrospective analysis of patient data from Radiation Therapy Oncology Group (RTOG) trials 74-01, 79-18, and 83-02 and the Northern California Oncology Group (NCOG) study 6G-82-1 was conducted. Patient data was supplied by both groups, and analyzed by the RTOG. Pretreatment characteristics including age, extent of surgery, Karnofsky Performance Status (KPS), and histopathology were collected; the only treatment variable evaluated was the use of BrdU during radiation therapy. Radiation dose, dose-fractionation schedule, use of chemotherapy, and/or type of chemotherapy was not controlled for in the analyses. Univariate and multivariate analyses were conducted to examine the potential treatment effect of BrdU on patient survival. RESULTS: Data from 334 patients treated with BrdU on NCOG 6G-82-1 and 1743 patients treated without BrdU on 3 RTOG studies was received. Patients were excluded from the review if confirmation of eligibility could not be obtained, if the patient was ineligible for the study they entered, if central pathology review was not done, or if radiotherapy data was not available. Patients treated according to the RTOG studies had to start radiotherapy within 4 weeks of surgery; no such restriction existed for the NCOG studies. To ensure comparability between the studies, patients from the NCOG studies who began treatment longer than 40 days from surgery were also excluded. The final data set included 296 cases from the NCOG studies (89%) and 1478 cases from the RTOG studies (85%). For patients with glioblastoma multiforme (GBM) the median survival was 9.8 months in the RTOG studies and 13.0 months in the NCOG trial (p < 0.0001). For patients with AA the median survival was 35.1 months for the RTOG studies and 42.8 months in the NCOG trial (p = 0.126). Univariate results showed consistent results favoring BrdU among patients over 30 years of age, across the extent of surgery, and for GBM patients. A proportional hazards regression model that included treatment, histopathology, KPS, age, and extent of surgery demonstrated that treatment with BrdU was included in the best model only for the GBM group of patients (risk ratio 0.83). CONCLUSIONS: Because of the heterogeneity of the treatment groups, including potentially important differences in pathology reviewers assessment of nonglioblastoma cases, differences in radiation dose and schedules, and chemotherapy during or after radiation, these analyses cannot provide the definitive answer as to whether BrdU given during radiation therapy improves survival in patients with malignant glioma. There does appear to be a favorable treatment effect seen in patients with GBM, with a lesser effect in patients with AA. 相似文献
966.
TJ Rosenbower JA Morris VA Eddy WR Ries 《Canadian Metallurgical Quarterly》1998,64(1):82-6; discussion 86-7
967.
VA Shapovalov 《Canadian Metallurgical Quarterly》1998,(8):17-18
It was established in experiment, that the changes of the natural resistance of organism indexes and of the peritoneal cavity cytology has compensatory-adaptational character while the denervation-adaptational syndrome occurrence and progress, which may be assessed as eustress. Vagotomy and operative trauma cause qualitatively different reactions of an organism. 相似文献
968.
969.
We describe the clinical course of a group of patients with primary sclerosing cholangitis who at presentation were diagnosed to have autoimmune hepatitis. The history of one such patient is described in detail. We also compare this atypical sclerosing cholangitis (group I) to typical sclerosing cholangitis (group II) and to autoimmune hepatitis with (group III) and without (group IV) cholestasis. At presentation, mean AST in groups I and III was similar and significantly higher than in group II (P < 0.05). Mean ALP was higher in sclerosing cholangitis than in autoimmune hepatitis but not significantly so. Triaditis was present in all patients in groups I, III, and IV. Piecemeal necrosis and multilobular collapse/fibrosis were equally frequent in groups I, III, and IV. Only the response to corticosteroids helped differentiate among groups. Groups III and IV responded by normalizing AST. In group I, AST improved, but never became normal. As ALP became disproportionately abnormal (ALP-predominant pattern), cholangiography was performed, and the diagnosis of primary sclerosing cholangitis was made in all group I patients. We recommend that cholangiography be performed early in patients with suspected autoimmune hepatitis who partially respond to corticosteroids and develop an ALP-predominant pattern. 相似文献
970.
As a fairly recent newcomer to nursing and as someone who feels responsible for maintaining his competence to practice, Jamie Simpson has a lot of questions. To get the answers, he often turns to his nurse colleagues. 相似文献