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Presents a study which measured the temperature rise and burnout currents in multilayer head transducers. Considerations in the design of such transducers for disk applications; Relation between temperature and resistance of permalloy materials; Method for determining burnout currents.

Reports on the potential of multilayer permalloy materials, with thin separation layer, to significantly increase both the density and speed of M-R memories. Factors which limit the density and speed of M-R memories; Operation of M-R memory elements; Description of M-R memory elements.

Examines a new operating mode discovered in transverse magnetoresistance memory cells. Illustration of a memory cell; Increase in the operating margin for the cells.

Presents a study that examined the perturbations to the Stoner-Wohlfarth threshold in 2x20 micrometer M-R memory elements. Details of the experiment; Theoretical studies; Summary and conclusions.

Presents a study which measured signal-to-noise ratio of multilayer magnetoresistive transducers. Properties of magnetic films prior to etching; Factors needed in the computation of the expected performance of in-gap transducers; Equation for computing the decay length of transducers.

The article presents a study on the method evaluation of quality assurance for nuchal translucency measurement in a large-scope study. It states that the study was conducted in unselected patients with singleton gestations between 10+3 weeks and 13+6 in 15 centers by the trained technicians. It reveals that there are still changes in nuchal translucency measurements, regardless of the training and continuous image review. Health care leaders' ongoing quality assessment is suggested.

Cyclin D1 is a critical regulator of androgen-dependent transcription and cell cycle progression in prostate cancer cells. Despite the influence of D-type cyclins on prostate cancer proliferation, few studies have examined the expression of cyclin D1 in localised tumours or challenged its relevance to disease progression. Cyclin D1 status was characterised using immunohistochemistry in 38 non-neoplastic prostate samples, 138 primary human prostate carcinomas, and three lymph node metastatic specimens. Relevance of cyclin D1 to preoperative prostate-specific antigen (PSA) levels, Ki-67 index, and p21Cip1 status was also examined. Cyclin D1-positive phenotype was increased in primary carcinoma compared to non-neoplastic tissue, and was evident in all lymph node metastases cases. Interestingly, at least three distinct localisation patterns were observed in the cyclin D1-positive cohort, wherein cytoplasmic localisation was identified in a large fraction, and this pattern was predominant in lower grade tumours. Relevance of altered cyclin D1 status was observed, wherein cyclin D1-positive tumours were associated with low preoperative PSA levels, consistent with in vitro reports that cyclin D1 may alter the expression of this tumour marker. Moreover, tumours with predominantly cytoplasmic cyclin D1 showed the lowest Ki-67 index, whereas nuclear cyclin D1 was associated with higher grade, elevated Ki-67, and increased nuclear p21Cip1. These data demonstrate that differential cyclin D1 status may influence clinicopathological parameters, and reveal new insight as to the regulation and potential consequence of cyclin D1 expression in prostate cancer. [ABSTRACT FROM AUTHOR]

This article presents comments on various studies related to breast cancer. It includes "Effect of Screening and Adjuvant Therapy on Mortality From Breast Cancer," "Image Quality and Breast Dose of 24 Screen-Film Combinations for Mammography" and "The Accuracy of Ultrasound, Stereotactic and Clinical Core Biopsies in the Diagnosis of Breast Cancer, With an Analysis of False-Negative Cases."

The incidence of placenta accreta should rise steadily over the next century as the frequency of Cesarean sections and advanced maternal age, both independent risk factors, increases. Patients who are at risk should be identified before an ultrasound examination and the characteristic findings searched for. In the first trimester, these include a low-lying sac that appears to be attached to the anterior wall of the uterus. As early as 16 weeks irregular vascular sinuses appear, which have turbulent flow within. The bladder wall may appear interrupted or have small bulges of the placenta into the bladder space. Absence of the normal echolucent space between the placenta and myometrium is not a reliable sign by itself, since this space may be absent in normal patients with an anterior placenta. Color Doppler will show that some of the placental sinuses traverse the uterine wall. Magnetic resonance imaging has not yet been shown to aid in the diagnosis, but in the future, with improvement of resolution and shortened sequences, it should be particularly useful in identifying the patients that have placenta percreta. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the ultrasonographic findings of ovarian ectopic pregnancies. Methods: The ultrasonographic reports, videotapes, medical records, and operative summaries were reviewed for all women with a confirmed diagnosis of an ovarian ectopic pregnancy. Examinations were personally conducted by a physician who was either a radiologist-obstetrician or an obstetrician-maternal-fetal medicine specialist. Results: Six cases were identified in the 13-year period studied. Menstrual ages ranged from 6 to 9 2/7 weeks. Most (5/6) patients had abdominal pain, with 3 demonstrating it before or at 7 weeks gestation. A wide echogenic ring with an internal echolucent area was seen in 5 of 6 patients; 1 of these also contained a yolk sac, and in another, fetal heart motion could be seen. The echogenic ring seemed to be on the surface of the ovary or within the substance of the ovary in all 5 patients. The echogenicity of the ring was greater than that of the ovary in the 5 patients in whom it was identified. At surgery, the ovarian pregnancies had the appearance of a hemorrhagic ovarian cyst in all 6 patients. In the patient in whom no echogenic ring was seen the pregnancy had ruptured. All 6 cases were biopsy proven. Conclusion: Ovarian pregnancies usually appeared on or within the ovary as a cyst with a wide echogenic outside ring. A yolk sac or embryo was less commonly seen. The appearance of the contents lagged in comparison with the gestational age. Early abdominal pain was common. [ABSTRACT FROM AUTHOR]

To demonstrate a standardized approach for the evaluation of cleft lip and palate by three-dimensional (3D) ultrasonography. This was a retrospective study of seven fetuses with confirmed facial cleft anomalies. Post-natal findings were compared to a blinded review of 3D volume data from abnormal fetuses with seven other normal fetuses that were matched for gestational age. Upper lip integrity was examined by 3D multiplanar imaging. Sequential axial views were used to evaluate the maxillary tooth-bearing alveolar ridge contour and anterior tooth socket alignment. Alveolar ridge disruption suggested cleft palate. Premaxillary protrusion, either by multiplanar imaging or surface rendering, indicated bilateral cleft lip and palate. Post-natal findings confirmed bilateral cleft lip and palate (four cases), unilateral cleft lip and palate (one case), and unilateral cleft lip (two cases). Multiplanar review identified all three fetuses with unilateral cleft lip, three of four fetuses with bilateral cleft lip, one fetus with unilateral cleft palate, and three of four fetuses with bilateral cleft palate. Surface rendering correctly identified all cleft lips, with the exception of one fetus, who was thought to have a unilateral cleft lip and palate, despite the actual presence of a bilateral lesion. One cleft palate defect was directly visualized by 3D surface rendering. No false-positives occurred. Interactive review of standardized 3D multiplanar images allows one to evaluate labial defects, abnormalities of the maxillary tooth-bearing alveolar ridge, and presence of premaxillary protrusion for detecting cleft lip and palate anomalies. Surface rendering may increase diagnostic confidence for normal or abnormal studies. This technology provides an array of visualization tools that may improve the prenatal characterization of facial clefts, particularly of the palate. [ABSTRACT FROM AUTHOR]

To describe three-dimensional (3D) ultrasonography (US) for the antepartum diagnosis of vasa previa. This was a descriptive study of two pregnant women who were suspected to have vasa previa by conventional gray-scale ultrasonography. Three-dimensional studies were also performed during the early third trimester to further investigate the possibility of this condition. In the first case, 3D US provided gray-scale multiplanar and surface-rendered views of an aberrant vessel over the internal cervical os. For the second case, a ‘flight-path’ technique allowed the examiner to follow axial views of the endocervical canal toward the internal os until an aberrant vessel was verified. The ‘niche-mode’ analysis, with and without color power Doppler ultrasonography, was also used to confirm the diagnosis. Three-dimensional ultrasonography offers several additional imaging tools that are not currently provided by more conventional ultrasonography for the detection of vasa previa. It represents an important adjunct to two-dimensional (2D) studies, especially when this diagnosis is questionable. [ABSTRACT FROM AUTHOR]

Objective The purpose of this study was to describe the antenatal ultrasonographic findings of fetuses with double-outlet right ventricle (DORV). Design The records were reviewed of all fetuses scanned in our ultrasound unit which were suspected of having DORV during a 6-year period ending in April 1996. A medical record search for all infants with a postnatal diagnosis of DORV was also undertaken to identify cases that were not detected antenatally. Records were examined to determine the accuracy of antenatal diagnosis and the reasons for diagnostic errors. Fetuses without follow-up were excluded. Results There were 20 fetuses with antenatally detected conotruncal defects that had DORV included in the differential diagnosis. Three fetuses were excluded, seven did not have DORV and ten were confirmed postnatally as having DORV. Two additional infants were found to have DORV from the medical record search, producing a total of 12 cases. Antenatal sonographic cardiac findings included malpositioned (overriding or transposed) great arteries (n = 11), ventricular septal defect (n = 11) and small pulmonary artery suggesting stenosis (n = 4). Confirmed post-natal cardiac findings that were missed antenatally included aortic coarctation (n = 2), right-sided aortic arch (n = 2) and pulmonary stenosis (n = 1). Seven of the 12 fetuses had extracardiac findings. Nine of the 12 fetuses tested had a normal karyotype. Eleven of the 12 infants were liveborn. Nine of these 11 survived the neonatal period and underwent surgical repair within the first year of life; two subsequently died. In total, seven fetuses survived and five did not. Conclusions Most fetuses with DORV can be identified antenatally as having an abnormal heart. However, it is very difficult to distinguish this particular defect from other conotruncal abnormalities. [ABSTRACT FROM AUTHOR]

Focuses on the nonuniform rotation of the magnetization in the multilayer M-R memory elements because of edge pinning. Data on element thresholds; Experimental elements used in the study; Values of the forward and reverse thresholds.

Presents a study which investigated the effects of substrate temperature on magnetoresistive ratio of the NiFeCo multilayer thin films. Experimental procedures; Results and discussion; Conclusion.

Focuses on a study which investigated magnetoresistive ratios of nickel iron cobalt multilayer films before and after annealing. Background on the role of demagnetizing fields in determining element performance; Description of experimental procedure; Results and discussion.

Focuses on a study which examined the effect of thermal agitation on the abruptness of the switching threshold for transverse magnetoresistive memory elements. Materials and procedure; Discussion on results; Background on theoretical considerations.