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Cardiac catheterization data from 54 investigations after Mustard's procedure were examined to study the influence of the operation on pressure events in the atria, great veins, and pulmonary circulation. Systemic venous atrial pressure tracings were characterized by a rapid, sharp 'y' descent. Pressure gradients between the venae cavae and systemic venous atrium were invariable, whether or not vena caval pathway obstruction was present, the 'y' trough and 'a' wave gradients being greater than the mean gradient. Pulmonary venous atrial pressure tracings were not different from normal except when tricuspid regurgitation was present. It is suggested that the baffle effectively reduces the size and compliance of the systemic venous atrium, but influences the pulmonary venous atrium to a lesser degree. The systolic pressure gradient from the left ventricle to pulmonary artery was decreased postoperatively, suggesting that it may be flow-related; the greatest changes were seen in the group with preoperative ventricular septal defect. The ratio of pulmonary: systemic vascular resistance did not change significantly after operation, and it is suggested that both the pre- and postoperative values were higher than normal. Examination of the left ventricular or pulmonary arterial mean pressure postoperatively should raise the suspicion of a complication, e.g. pulmonary venous obstruction or tricuspid regurgitation. 相似文献
145.
Krippner Stanley; Achterberg Jeanne; Bugental James F. T.; Banathy Bela; Collen Arne; Jaffe Dennis T.; Hales Susan; Kremer Jurgen; Stigliano Anthony; Giorgi Amadeo; May Rollo; Michael Donald N.; Salner Marcia 《Canadian Metallurgical Quarterly》1988,43(10):819a
Comments that B. F. Skinner (see record 1988-00027-001) has presented an egregiously inaccurate characterization of humanistic psychology. The authors note that Skinnerian radical behaviorism emphasizes behavior, science, and technology, while humanistic psychologies emphasize human beings. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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A modern outline of the physiology of coagulation, a simple approach to the use of laboratory investigation for patients with possible clotting disorders in unexplained hematuria and several illustrative cases are presented. The diagnosis and management of localized fibrinolysis in the genitourinary tract and intravascular coagulation as possible causes of post-prostatectomy hemorrhage are discussed. A minimum of a platelet count, fibrinogen assay and, if possible, measurement of fibrinogen-related antigens should be obtained before administration of epsilon aminocaproic acid. 相似文献
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IuIu Bredikis EIu Va?tsekavichius ED Rimsha AP Dobkevichene 《Canadian Metallurgical Quarterly》1978,18(10):43-51
The frequency of disorders of the cardiac rhythm during injection of a contrast medium into the coronary vessel under different conditions was studied in 214 patients. Atropine premedication was applied as a preventive factor in 142 patients, atrial stimulation in 60, and both factors simultaneously in 12. In 10 patients a single injection of the contrast medium was performed without preventive measures. In 20 patients the changes were studied by recording the potentials of the bundle of His and the arterial pressure. On the basis of the bundle of His ECG data it is concluded that atropine and atrial stimulation produce an effect on individual links of the complex mechanism underlying the effect of the contrast medium on the cardiac conduction system. 相似文献
149.
Holland Scott K. Orphanoudakis Stelios C. Jaffe C. Carl 《IEEE transactions on bio-medical engineering》1984,(9):626-631
The quantitative capability of pulsed Doppler ultrasound in clinical practice is limited by the effects of frequency-dependent attenuation of ultrasound in tissue, as well as several other spectral-broadening mechanisms which distort the Doppler spectrum of an ultrasonic echo. In this communication, we present results of in vitro experiments which demonstrate the magnitude of the errors expected in clinical measurements of blood flow parameters when frequency-dependent attenuation Of ultrasound in biological tissue is ignored. It is shown that errors as large as 15 percent may occur in Doppler measurements of blood flow velocity through 7 cm of intervening tissue. A comparison is also made between experimental results and a theoretical model which includes the effects of scattering and attenuation. 相似文献
150.
RV Lebo ED Lynch MS Golbus RR Flandermeyer PH Yen LJ Shapiro 《Canadian Metallurgical Quarterly》1993,46(6):652-658
X-linked ichthyosis results from steroid sulfatase (STS) deficiency; 90% of affected patients have a complete deletion of the entire 146 kb STS gene on the distal X chromosome short arm (Xp22.3). In these families prenatal diagnosis and carrier testing can be completed in 2 days by hybridizing simultaneously 2 different cosmid probes labeled with fluorescein or Texas red and counterstaining interphase nuclear DNA with DAPI. An STS gene probe labeled with Texas red hybridizes specifically to the steroid sulfatase gene on the X chromosome. A second flanking probe labeled with fluorescein hybridizes to both the normal Y chromosome and normal and STS deleted X chromosomes. In this fashion the interphase nuclei of normal males, affected males, normal females, and carrier females can be distinguished unambiguously. Because normal males and carrier females each show two yellow-green fluorescein spots and one Texas red STS spot, use of this test prenatally requires determining fetal sex independently with repetitive X and Y chromosome-specific probes. This procedure can be used with lymphocytes, direct and cultured chorionic villus cells, direct and cultured amniocytes, and fibroblasts. Similar methods are anticipated to be useful for rapid diagnostic assessment of other aneuploid gene disorders. 相似文献