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71.
Ohne ZusammenfassungHierzu Taf. X. Fig. 4.  相似文献   
72.
Whole-heart cine MRI using real-time respiratory self-gating.   总被引:1,自引:0,他引:1  
Two-dimensional (2D) breath-hold cine MRI is used to assess cardiac anatomy and function. However, this technique requires cooperation from the patient, and in some cases the scan planning is complicated. Isotropic nonangulated three-dimensional (3D) cardiac MR can overcome some of these problems because it requires minimal planning and can be reformatted in any plane. However, current methods, even those that use undersampling techniques, involve breath-holding for periods that are too long for many patients. Free-breathing respiratory gating sequences represent a possible solution for realizing 3D cine imaging. A real-time respiratory self-gating technique for whole-heart cine MRI is presented. The technique enables assessment of cardiac anatomy and function with minimum planning or patient cooperation. Nonangulated isotropic 3D data were acquired from five healthy volunteers and then reformatted into 2D clinical views. The respiratory self-gating technique is shown to improve image quality in free-breathing scanning. In addition, ventricular volumetric data obtained using the 3D approach were comparable to those acquired with the conventional multislice 2D approach.  相似文献   
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Conclusion  The ACCF/ASNC AC for SPECT MPI provides recommendations for the appropriate use of SPECT MPI. After the publication of the AC document in 2005, the AC has been used by nuclear cardiology practices with many clinical studies evaluating the list of indications in routine clinical practice. From these data. ASNC recommends minor but important changes to the indication list, suggesting the addition of 6 new indications and the modification of the definitions for “chest pain syndrome” and “CHD high risk.”. An objective review of existing indications focused on only those indications that had significant variability among the reviewers (n=20). These indications were reviewed in the presence of existing and new evidence-based data, and ASNC recommends that the grades for 6 indications be re-evaluated. The AC for SPECT MPI will require periodic review as new evidence becomes available or as clinical practice evolves. ASNC recognizes the importance of these criteria to improve the quality of patient care, and it will continue to play a key role in assembling the information for this ongoing review. From the current summary of evidence, ASNC consensus opinions, and ASNC recommendations in this document, ASNC strongly recommends that the AC guidelines be reviewed Prepared by the American Society of Nuclear Cardiology Quality Assurance Subcommittee for Quality in Imaging Standards. Reviewed by members of the American Society of Nuclear Cardiology Quality Assurance Committee. Approved by the American Society of Nuclear Cardiology Board of Directors, September 6, 20.  相似文献   
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BACKGROUND:: During the 1980s reports describing the effect of systemic chemotherapyon brain metastases from chemosensitive tumours emerged, includinga few retrospective reports on small cell lung cancer (SCLC)patients. DESIGN:: Previously untreated SCLC patients with no other malignancy,but in some cases with mixed histological subtype, who had symptomaticbrain metastases verified by contrast enhanced CT-scan, weretreated with a multidrug combination chemotherapy regimen andno cranial irradiation. Radiotherapy was optional at cranialrelapse or progression at the discretion of the physician incharge. The intracranial effect was evaluated by 4-weekly CT-scanand neurological examination, according to a standardized scoringsystem. END POINTS:: Intracranial response, duration of response, neurological score,terminal CNS status, and survival. RESULTS:: 21 patients were included, corresponding to 8.6% of consecutiveSCLC patients at our institution. 8 patients died before follow-upleaving 13 evaluable for response. In the former group, allpatients had WHO performance status of 3–4 compared to6/13 in the latter group. Of the 13 evaluable patients, 1 hadearly progression in the CNS and 1 had no change. 11 had CT-scanverified response, with a median duration of 135 days. Mostpatients, including all complete responders, had improvementin their neurological score. 6 out of 11 responders died withoutactive CNS disease. The crude median survival was 111 days,whereas the median survival(early deaths excluded) was 197 days. CONCLUSION:: Systemic combination chemotherapy was effective for palliationof initial brain involvement in the majority of patients ina small consecutive series. The role of consolidating cranialirradiation in responders should be assessed by a randomizedtrial. small cell carcinoma, brain metastases, chemotherapy  相似文献   
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Summary Tibial hypo-/aplasia with preaxial syn- and polydactyly is a rare autosomal dominant condition. Fewer than 20 cases have so far been described. One is presented here.  相似文献   
79.
In this paper we propose a method for construction of feed-forward neural classifiers based on regularization and adaptive architectures. Using a penalized maximum likelihood scheme, we derive a modified form of the entropic error measure and an algebraic estimate of the test error. In conjunction with optimal brain damage pruning, a test error estimate is used to select the network architecture. The scheme is evaluated on four classification problems.  相似文献   
80.
OBJECTIVE: The aim was to establish the potential efficacy, tolerabilityand side-effect profile of electromagnetic therapy as an adjunctto conventional dressings in the treatment of venous leg ulcers. METHOD: A prospective, randomized, double blind controlled clinicaltrial was carried out in a dedicated leg ulcer clinic basedin one urban general practice. Nineteen patients with leg ulcersof confirmed venous aetiology were assessed. The main outcomemeasures were rate and scale of venous leg ulcer healing, changesin patient-reported pain levels, quality of life, degree ofmobility, side effect profile and acceptability to patientsand staff. RESULTS: Sixty-eight per cent of patients attending this dedicated clinicachieved improvements in the size of their ulcer (4, 21%, healedfully) and in reduced pain levels (P < 0.05) during the trial,despite the chronicity of ulcer histories. Patients treatedwith electromagnetic therapy at 800 Hz were found at day 50to have significantly greater healing (P < 0.05) and paincontrol (P < 0.05) than placebo therapy or treatment with600 Hz. All patients reported improved mobility at the end ofthe study. The electromagnetic therapy was well tolerated bypatients, with no differences between groups in reporting adverseevents, and proved acceptable to staff. CONCLUSION: Despite the small numbers in this pilot study, electromagnetictherapy provided significant gains in the healing of venousleg ulcers and reduction in pain. Keywords. Electromagnetic therapy, RCT, leg ulcers, primary care.  相似文献   
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