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Stewart W J - - 1991
Doppler color flow imaging provides important qualitative information about the location and spatial distribution of intracardiac blood flow. However, the effect of instrument-related variables on the size of color Doppler images requires further definition. Flow of a silicone particle solution was established in a tube or cylinder and scanned as ...
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Schneider H - - 1991
A comparative study of 13 blood genetic systems and pelage color variation was performed in four wild populations of Alouatta belzebul. The animals from the west bank of the Tocantins River showed less color variation than those from the east bank, as well as less than those from Tocantins Island. ...
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Jaffe R - - 1991
Characteristic changes of low resistance and high diastolic blood flow velocity were identified by Doppler studies starting in the early phase of the second trimester. These changes were attributed by some authors to trophoblastic invasion of the uterine vasculature converting the uterus into a low-resistance organ. Because of technical limitations ...
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Landwehr P - - 1991
The accuracy of quantifying the degree of vascular stenosis with color Doppler flow imaging (7.5-MHz, linear array system) was determined in an experimental study carried out on six concentric and five eccentric model stenoses (cross-sectional area reduction, 13.4%-93.8%). The measurements were made with use of pulsatile flow at four different ...
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Recusani F - - 1991
While color Doppler flow mapping has yielded a quick and relatively sensitive method for visualizing the turbulent jets generated in valvular insufficiency, quantification of the degree of valvular insufficiency has been limited by the dependence of visualization of turbulent jets on hemodynamic as well as instrument-related factors. Color Doppler flow ...
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Mehta R H - - 1991
Two-dimensional and color Doppler echocardiography accurately detected the presence of an atrial septal defect (ASD) in 47 of 50 adults (mean age 40 years) confirmed by surgery or cardiac catheterization, or both. It correctly categorized all patients with ostium secundum and ostium primum ASD but misdiagnosed 3 of 5 patients ...
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Harrison J D - - 1991
We have evaluated the solid state laser as a means of determining testicular blood flow at operation. A solid state laser was used to measure blood flow before mobilization of cryptorchid testes, and subsequently after mobilization and placement within a subcutaneous scrotal pouch. Testicular volume was calculated. The median blood ...
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Widmark A - - 1991
As arginine-vasopressin (AVP) has been suggested as a possible paracrine regulator in the testis, the present study was designed to evaluate the effects of AVP on testicular blood flow and vascular permeability. Intratesticular injection of AVP caused a dose-dependent decrease in total testicular blood flow, with 1 ng AVP being ...
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Ludomirsky A - - 1991
Color-flow Doppler is used for special localization of cardiac flows. The transeptal jet in supracristal ventricular septal defect (VSD) is directed toward the pulmonary valve and is often difficult to distinguish from the right ventricular (RV) outflow tract flow. Pulsed- and continuous-wave Doppler can misread the VSD jet as a ...
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Ralls P W - - 1991
Sixteen patients with hepatocellular carcinoma (HCC) were assessed with color Doppler sonography (CDS) for flow compared to normal hepatic parenchyma. Nine showed moderate increased flow, and two revealed marked increased flow. In most instances, the increased flow was peripheral. Color Doppler was also useful in assessing seven patients with portal ...
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Rifkin M D - - 1991
Endorectal ultrasound of the prostate with color Doppler is a new technique to identify internal vasculature and flow. In a period of one year more than 500 men have been examined with this technique. The normal prostate will demonstrate flow within the surrounding vasculature; there is no distinguishing flow among ...
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Gonzalez R R RR - - 1991
This paper describes a method for the use of a personal computer in developing color modulated spectral maps of blood flow echoes from a Doppler flowmeter. The acoustical signal from a Doppler flowmeter is digitized and transformed into the frequency domain with a fast Fourier technique with the use of ...
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Lee S E - - 1991
DNA flow-cytometric analysis was performed on the testicular needle biopsies of 25 infertile men with azoospermia or oligozoospermia to evaluate the ability of DNA histograms in order to detect and quantify alterations in spermatogenesis. Concomitant histopathologic study was performed on the tissues from needle biopsy. In contrast to difficulty in ...
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Hata K - - 1991
Transvaginal color and pulsed Doppler ultrasound examinations were made on 40 patients to assess hemodynamics in the pelvis. Use of a special probe for transvaginal scanning led to superb simultaneous visualization of structures and blood flow, and we noted various events, even in the small, deep and/or peripheral vessels. Some ...
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Jain S P - - 1991
To evaluate the factors influencing flow information displayed by the power operating mode, color Doppler flow mapping was used to image the flow in an in vitro left heart pulse duplicator system. The effect of changing one instrument setting, such as pulse repetition frequency, color filter and frame rate while ...
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Saitoh M - - 1991
Color Doppler flow imaging has been used as a supplementum to the ultrasound guidance in 16 renal biopsies, 8 nephrostomies and 6 renal cyst punctures. Puncture of intrarenal vessels could be avoided and fluid flow as in aspiration of cyst fluid or urine and drug injection could be monitored. No ...
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Strohmaier W L - - 1991
The penile arteries of 18 men with erectile dysfunction were examined by angiodynography (color-coded duplex sonography). Blood flow velocity was measured before and after intracavernous injection of papaverine/phentolamine. The angiodynographic findings were compared to arteriography. Normal values of peak flow velocity (after injection) were obtained from 6 men with normal ...
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Tamura T - - 1991
The use of color Doppler flow mapping systems for quantitative in vitro studies of flow fields is examined and illustrated. A 5-MHz color Doppler system was used, and the resolution was determined by comparing the results of flow-field measurement for steady parabolic pipe flow with calculated values. The velocity accuracy ...
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Bogdahn U - - 1990
We investigated the diagnostic potential of transcranial color-coded real-time sonography in 52 individuals using a phased-array ultrasound system with color-coded blood flow representation. Ultrasound scans in the axial and coronal planes were feasible through temporal acoustic bone windows in 49 subjects, enabling depiction of the main parenchymal and vascular structures ...
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Frazin L J - - 1990
To determine whether rotational blood flow or chiral asymmetry exists in the human descending thoracic aorta, we established the ability of color Doppler ultrasound to detect rotational flow in a tornado tube model of a vortex descending fluid column. In a model of the human aortic arch with a pulse ...
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Rittgers S E - - 1990
The capability of the recently introduced Doppler color-flow mapping devices to accurately detect flow patterns in the region of an arterial stenosis was evaluated by use of an in vitro flow model. Pulsatile flow simulating that in a low-resistance vessel was induced through a straight acrylic tube, which alternatively contained ...
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Sommer R J - - 1990
In children with a ventricular septal defect, transseptal blood flow has been demonstrated angiographically to be bidirectional in all but the smallest defects. To investigate this phenomenon noninvasively, two-dimensional Doppler color flow echocardiography was used in 77 patients (aged 1 day to 15.5 years, mean 24 months). During isovolumetric contraction, ...
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Utsunomiya T - - 1990
The Doppler color jet area depicting a regurgitant or shunt lesion may be useful in estimating its severity. However, color jet area may be affected by technical factors. We studied the combined effects of Doppler angle, frame rate, and scanning direction on the Doppler color jet area of a free ...
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Ciricillo S F - - 1990
Two-dimensional echocardiography complemented with color-flow imaging and pulsed Doppler ultrasound was used to evaluate one fetus and five neonates with a vein of Galen malformation who had severe high-output congestive heart failure and cranial bruits at birth. Intracranial blood flow through the vein of Galen malformations, cardiac status, and direction ...
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Vorwerk D - - 1990
Color-coded image-directed Doppler sonography (CCIDS) was used in the follow-up of self-expandable vascular endoprostheses and was compared with the results of digital subtraction angiography and Doppler pressure indices. The stents were implanted in iliac and femoral arteries or hemodialysis fistulae of 26 patients. The aim of the study was to ...
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Turner T T - - 1990
Testicular and reference organ blood flows and testicular temperatures were determined in peripubertal and mature rats with and without experimental left varicocele (ELV). Testicular blood flow and temperature were significantly increased bilaterally 30 days after surgery to induce unilateral varicocele, and this was the case in both the younger and ...
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Mehta R H - - 1990
Transesophageal Doppler color flow imaging was performed in 19 adult patients (mean age 35 years) with an atrial septal defect demonstrated by cardiac catheterization or at surgery, or both. The transesophageal study correctly identified and classified 19 of 19 shunts in contrast to 16 of 18 shunts identified by the ...
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Nelson L H - - 1990
Vasa previa, which is associated with high fetal mortality, is present when fetal vessels cross the internal cervical os as a velamentous insertion of the umbilical cord with or without a succenturiate lobe or bilobate placenta. This is the first case report of vasa previa not associated with a succenturiate ...
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Knighton R A - - 1990
Color flow sonography permits noninvasive examination of the deep venous system in the lower extremity. In many patients, the modality is sufficiently accurate to serve as the sole diagnostic procedure for suspected deep venous thrombosis. Over 1,500 color flow sonographic examinations of the lower extremity have been performed at our ...
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Tsutsui T - - 1990
In order to better understand androgen secretion in the tom cat during the breeding season, observations of diurnal changes in peripheral blood testosterone (T) levels, were made and the relation between androgen levels (androstenedione (A), 5 alpha-dihydrotestosterone (DHT). T) in testicular and peripheral vein blood was borne. Histologic examinations of ...
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Pascual J A - - 1990
To determine the effects of unilateral testicular vein and artery ligation in the immature rat on the function and final location of the testis at adulthood, 10-day-old male rats underwent either a sham operation or unilateral ligation of these vessels of the still undescended testis. Testicular location, blood flow, size ...
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Gardin J M - - 1990
It has been suggested that a major advantage of Doppler color flow mapping is its ability to visualize areas of disturbed ("turbulent") flow, for example, in valvular stenosis or regurgitation and in shunts. To investigate how various color flow mapping instruments display disturbed flow information, color image processing was used ...
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Cosgrove D O - - 1990
The color Doppler signals in 60 patients with breast masses were assessed subjectively, and a regional grading method was developed for quantitation of displayed blood vessel density. Among 21 patients with breast carcinoma, moderate or high flow was demonstrated in all but one, with an average of 0.5 vessels per ...
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Garrahy P J - - 1990
Few data exist regarding the consequences of abnormalities of segmental contraction on intraventricular flow patterns. The development of color Doppler flow imaging has now permitted the visualization of intraventricular blood flow patterns. Therefore, we performed Doppler flow mapping in 41 patients (12 with normal left ventricular contraction, eight with hypokinesis ...
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Burks D D - - 1990
Color Doppler sonography was performed in 32 patients with a painful scrotum in whom testicular ischemia from torsion or postherniorrhaphy was clinically suspected. Surgical correlation was available in 15 patients, and scintigraphic correlation was available in 17 patients. Seven of the 32 patients were diagnosed as having testicular ischemia from ...
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Grassi C J - - 1990
Real-time ultrasonography (US) and color Doppler flow mapping were used to determine prospectively whether venous thrombosis in the upper extremity could be imaged as accurately as with conventional contrast venography. Thirteen patients were imaged. The diagnosis of spontaneous (or "effort") thrombosis was made clinically and confirmed initially at venography (n ...
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Damber J E - - 1990
Testicular blood flow was measured by means of Xenon-133 clearance in control rats and rats treated with guanethidine for 3 weeks. Plasma and testis testosterone concentrations were also measured, and the effect of hCG-treatment was examined. No difference in testicular blood flow between the control group and the guanethidine-treated group ...
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Arduini D - - 1990
A study was made in order to assess whether the combined use of color flow mapping and conventional pulsed Doppler could improve the accuracy of blood flow velocity waveform analysis in fetal and placental circulations. Fifty patients were studied at 18 to 20 or 26 to 28 weeks of gestation ...
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Ishida H - - 1990
We measured serum inhibin levels in eight untreated patients with prostatic cancer undergoing castration by RIA using an antiserum against 31-kDa bovine follicular fluid inhibin. The inhibin concentrations in testicular tissue and spermatic venous blood were also measured in six of these patients. Serum inhibin levels (mean +/- SD, 377.8 ...
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Winters S J - - 1990
The secretion of inhibin by the testis into the circulation was studied by measuring immunoreactive inhibin concentrations in spermatic vein blood samples drawn at 15 min intervals for 4 h. Mean spermatic vein inhibin levels were four times the levels in peripheral blood whereas spermatic vein testosterone (T) levels were ...
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Sumner D S - - 1990
Color-flow imaging of the cervical vasculature has several distinct advantages compared with conventional duplex scanning: it facilitates identification of the carotid artery, its bifurcation, branches, and other cervical vessels, especially the vertebral arteries; decreases the time required for longitudinal surveys; aids in the recognition of kinks, coils, and occluded vessels; ...
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Holen J - - 1990
The goal of this investigation was to explore the relationship between orifice flow rate and the dimensions of the resulting color jet. Equations were derived which describe flow rate as a function of the color jet dimensions, instrument characteristics, and a coefficient which represents the unknown velocity profile across the ...
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Wang J E - - 1990
A method for quantification of regurgitant volume in mitral regurgitation (MR) was studied. 31 cases of MR were investigated with color Doppler. The reliability of measuring velocity by Doppler and the influence of pressure gradient on MR were assessed and confirmed by experimental device. The results suggested that the best ...
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Kurjak A - - 1990
Transvaginal color Doppler was used to analyze a group of 19 healthy, 48 infertile and 8 postmenopausal women; 67 patients with uterine and 151 patients with adnexal masses, and 19 patients with a suspected ectopic pregnancy. The ultrasonographer had not been informed of other clinical findings and indications for operative ...
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Sirvent J J - - 1990
In a group of 31 patients with idiopathic varicocele (IV), testicular biopsy showed a decreased tubular diameter, hyperplasia in the number of Leydig's cells (LC; many with cytoplasmic vacuolization and atrophy) and a decrease in the number of positive LC in testicular tissue sections stained with the testosterone peroxidase-antiperoxidase method. ...
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Yoshida K - - 1989
To evaluate left-to-right shunts after percutaneous balloon mitral valvuloplasty, we studied 15 consecutive patients by using transesophageal color Doppler flow-imaging system. Transesophageal color Doppler examinations were performed five times in each patient (before valvuloplasty and 1 day, 1 week, 1 month, and 6 months after valvuloplasty). No shunt flow was ...
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Tessler F N - - 1989
Five neonates with cranial arteriovenous malformations were studied with color Doppler sonography. Excellent correlation was found between sonography and subsequent angiography. In three patients with vein of Galen aneurysms, sonography showed a cystic structure with rapid or swirling flow. Careful adjustment of the color Doppler system was required to demonstrate ...
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Yamagishi M - - 1989
To examine whether CBF can be imaged by color Doppler technique, we visualized CBF using a transesophageal color Doppler imaging system. In 36 of 39 patients with normal coronary arteriograms after heart surgery, the LMT and the proximal LAD were clearly imaged by 2-dimensional echocardiography. Among them, CBF was coded ...
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Widmark A - - 1989
To study the effects of LH on total testicular blood flow and microcirculation, rats were treated with 2.5 or 25 micrograms LH sc and measurements were made on control rats and on LH-treated rats 1, 2, 3, 4, 6 and 12 h, after treatment. After treatment with 25 micrograms LH, ...
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Turner T T - - 1989
Experimental left varicocele (ELV) is known to induce bilateral changes in the rat testis that, where comparisons are possible, are similar to the changes induced by unilateral varicocele in the human. In the present study, we have determined whether or not left adrenal products are important to the changes induced ...
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