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Dive into the research topics where Isabel Ramos is active.

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Featured researches published by Isabel Ramos.


Ultrasound in Medicine and Biology | 1988

Detection of neovascular signals in a 3 day walker 256 rat carcinoma by CW doppler ultrasound

Isabel Ramos; Leonardo A. Fernandez; Steven S. Morse; Karen L. Fortune; Kenneth J. W. Taylor

An animal model was used to study tumor blood flow by the Doppler CW technique. The objective was to determine when neovascularity could be detected as a function of tumor size and time since transplantation. A Walker 256 carcinosarcoma tumor was inoculated into the flank of 17 Sprague-Dawley rats. Doppler examinations, using a 9 MHz CW probe, were performed daily from day 0 to day 7. The contralateral flank was used as a control. No signals were detected from the control side nor from the inoculated side until day 3. By day 3, Doppler signals could be easily detected in all tumor implants with a minimum weight of only 50 mg. These signals showed a mean systolic frequency shift of 3.3 +/- 0.47 kHz at 3 days and 3.46 +/- 0.58 kHz at 7 days. The diastolic Doppler shifted frequency was 1.78 +/- 0.31 kHz at 3 days and 1.88 +/- 0.23 kHz at 7 days giving a Pourcelot index of 0.47 +/- 0.1 at 3 days and 0.46 +/- 0.09 at day 7. These figures indicate the presence of low impedance vessels with high velocity flow such as has been reported in many human tumors. The vascular morphology was further evaluated by digital angiography which demonstrated coincidence between the site of the high velocity Doppler signals and the presence of arteriovenous anastomoses manifested by simultaneous arterial and venous filling. Further infusion techniques using India ink or Microfil showed the chaotic arrangement of tumor vessels located around the growing edge of the tumor implant. The development of such vascularity is a well-recognized prerequisite for tumor growth and invasion.(ABSTRACT TRUNCATED AT 250 WORDS)


Ultrasound in Medicine and Biology | 1993

Endovaginal pulsed and color doppler in first-trimester pregnancy

Evan H. Dillon; Cara Q. Case; Isabel Ramos; Christy K. Holland; Kenneth J. W. Taylor

Endovaginal pulsed and color Doppler techniques were used to evaluate 23 unselected first-trimester pregnancies prior to elective abortion. Mean estimated gestational age was 8.9 +/- 1.6 weeks (range = 6.6-13.0). Low impedance, high velocity peritrophoblastic flow was seen in all cases. Mean peak systolic and end-diastolic velocities were 41.0 +/- 19.7 and 22.9 +/- 6.5 cm/s; mean resistance index (RI) was 0.41 +/- 0.10. Forty-five uterine arteries were evaluated with mean peak systolic and end-diastolic velocities of 44.1 +/- 14.7 and 7.6 +/- 4.3 cm/s; mean RI was 0.81 +/- 0.10. The peritrophoblastic and uterine artery velocities did not correlate with gestational age. Both ovaries were evaluated in 14 patients. One had no detectable flow in either ovary. For the active ovary in the other 13 patients, mean peak systolic and end-diastolic velocities were 27.4 +/- 9.9 and 15.2 +/- 5.9 cm/s; mean RI was 0.44 +/- 0.09. The corresponding values for the inactive ovary were 8.9 +/- 3.8 cm/s, 2.0 +/- 2.0 cm/s, and 0.76 +/- 0.22. These results can be used as a baseline for future studies of abnormal pregnancies.


Journal of Clinical Gastroenterology | 1991

Ultrasound imaging of pancreatico-duodenal transplants.

Lawrence N. Milner; Isabel Ramos; William H. Marks; Kenneth J. W. Taylor

A preliminary investigation of the role of ultrasound, including color and duplex Doppler, was performed in recipients of cadaveric pancreatico-duodenal transplants. Twenty such examinations were done on three patients. Three different complications were noted: rejection, pancreatitis, and peripancreatic abscess. The mean normal resistive index (RI) was 0.71 +/- 0.12. The normal allograft anteroposterior (AP) dimension ranged from 1.5 to 2.0 cm. Intraparenchymal and main feeding vessels were demonstrated easily. RI calculations alone were not helpful in diagnosing graft rejection. However, this diagnosis can be made using a new biochemical marker, serum anodal trypsinogen. We conclude that when used in conjunction with a reliable biochemical marker for rejection (serum anodal trypsinogen), ultrasound, including color and duplex Doppler, provides an important adjunct for the rapid, inexpensive, and complete evaluation of patients with pancreatico-duodenal transplants.


European Journal of Echocardiography | 2011

Spontaneous closure of a left ventricle pseudoaneurysm following apical venting

Ricardo Lopes; Jorge Almeida; João Carlos Silva; Pedro Bernardo Almeida; António J. Madureira; Isabel Ramos; Paulo Pinho; Maria Júlia Maciel

Cardiac surgery is the second most frequent aetiology of left ventricular pseudoaneurysm (LVP). Left ventricular apical venting is a recognized cause of LVP. Prompt surgical treatment is usually needed since there is a high risk of rupture and spontaneous closure is very rare. We describe a case of spontaneous closure of a left ventricle pseudoaneurysm following apical venting.


Revista Portuguesa De Pneumologia | 2014

Myocardial cleft in a patient with Takotsubo cardiomyopathy: An unusual association identified by cardiac magnetic resonance

Vânia Ribeiro; Teresa Pinho; Sílvia Marta Oliveira; António J. Madureira; Isabel Ramos; Maria Júlia Maciel

We present the case of an 84-year-old woman admitted for Takotsubo cardiomyopathy complicated by congestive heart failure. Cardiovascular magnetic resonance (CMR) imaging was performed on day five and confirmed severely depressed left ventricular systolic function with typical apical ballooning. In steady-state free precession long-axis cine imaging, a basal inferior myocardial cleft was also observed, with no signs of myocardial noncompaction or regional wall motion abnormalities involving this segment. The pre-discharge CMR study confirmed the presence of a basal inferior myocardial cleft and significant improvement in left ventricular systolic function. Myocardial clefts are congenital abnormalities that have been described in healthy individuals as well as in the setting of hypertrophic cardiomyopathy, but it is not clear whether it is a benign structural variant or a distinct cardiomyopathy phenotype. To our knowledge this is the first reported case of this abnormality in a patient with Takotsubo cardiomyopathy.


Canadian Journal of Cardiology | 2013

An Unusual Pattern of Aortic Regurgitation in a Bicuspid Aortic Valve

Alexandra Sousa; Jorge Almeida; António J. Madureira; Jorge Casanova; Isabel Ramos; Maria Júlia Maciel; Paulo Pinho

An Unusual Pattern of Aortic Regurgitation in a Bicuspid Aortic Valve Alexandra Sousa, MD, Jorge Almeida, MD, Antonio Madureira, MD, Jorge Casanova, MD, Isabel Ramos, MD, PhD, Maria Julia Maciel, MD, PhD, and Paulo Pinho, MD Cardiology Department, Centro Hospitalar Sao Joao, Porto, Portugal Cardiothoracic Surgery Department, Centro Hospitalar Sao Joao, Porto, Portugal Radiology Department, Centro Hospitalar Sao Joao, Porto, Portugal


Radiology | 1988

Correlation of Doppler US tumor signals with neovascular morphologic features.

Kenneth J. W. Taylor; Isabel Ramos; Darryl Carter; Steven S. Morse; D. P. Snower; K. Fortune


Radiology | 1987

Focal liver masses: differential diagnosis with pulsed Doppler US.

Kenneth J. W. Taylor; Isabel Ramos; Steven S. Morse; K. Fortune; L Hammers; C R Taylor


Radiology | 1992

Ectopic pregnancy: evaluation with endovaginal color flow imaging.

J. S. Pellerito; Kenneth J. W. Taylor; C Quedens-Case; L. W. Hammers; Leslie M. Scoutt; Isabel Ramos; W R Meyer


Radiology | 1988

Tumor vascular signals in renal masses: detection with Doppler US.

Isabel Ramos; Kenneth J. W. Taylor; R. Kier; P. N. Burns; D. P. Snower; Darryl Carter

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