Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    ISSN: 1432-1084
    Keywords: Breast neoplasms, diagnosis ; Breast neoplasms, MR studies ; MRI, Gd-DTPA ; MRI, technology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract State-of-the-art screening mammography allows the detection of nonpalpable breast lesions in approximately 30 % of patients. The presence of clustered microcalcifications without evidence of solid tumors usually requires further investigations, mainly biopsy. A 1.5-T magnet with a single breast coil was used to evaluate 32 patients with indeterminate mammography suggestive of microcalcifications prior to surgery. Both spin-echo (SE) and gradient-echo (GE; 2D fast low-angle short [FLASH]) techniques were utilized before and after injection of 0.2 mmol/kg Gd-DTPA. Upon surgery tumor diameters ranged between 3 and 10 mm. Use of MRI demonstrated 87.5 % overall accuracy, 83.3 % sensitivity, and 92.9 % specificity. False-negative MRI results were in situ carcinomas less than 5 mm in size. All the correctly diagnosed carcinomas measured between 5 and 10 mm. Partial volume is probably the greatest limit of this technique and lesions equal to or smaller than 5 mm are only rarely detected. The GE and SE sequences demonstrated comparable results.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Circuits, systems and signal processing 16 (1997), S. 703-718 
    ISSN: 1531-5878
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology
    Notes: Abstract Discrete-time linear periodic single-input/single-output (SISO) systems having uniform relative degree are considered. A closed-form expression of the blocking input is derived and exploited to obtain a computationally advantageous characterization of the structural zeros. Indeed, it suffices to compute the eigenvalues of a suitably defined (n × n) matrix, wheren is the system order. It is shown that, in contrast to the general case studied in previous papers, the number of zeros of linear periodic SISO systems with uniform relative degree is always time invariant and equal to the difference between the system order and the relative degree. The new characterization is also used to provide a simple expression for the zeros of linear periodic systems described by input-output difference equations.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...