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101.
102.
The effects of adenosine and sodium nitroprusside (SNP) on central hemodynamics and myocardial blood flow and metabolism were investigated postoperatively after elective coronary artery bypass (CABG) surgery in ten sedated and mechanically ventilated patients in the intensive care unit. During three consecutive 15-min periods, SNP (0.8 +/- 0.1 micrograms.kg-1 x min-1), adenosine (88.9 +/- 13.3 micrograms.kg-1 x min-1), and then again SNP (0.7 +/- 0.1 micrograms.kg-1 x min-1) were infused to control postoperative hypertension at a mean arterial pressure of approximately 80 mm Hg. Systemic and pulmonary hemodynamics and global (coronary sinus flow, CSF) as well as regional (great cardiac vein flow, GCVF) myocardial blood flow and metabolic variables were measured. During adenosine infusion, in comparison to SNP, heart rate was unchanged, stroke volume index and cardiac index increased (24% and 32%, respectively), and the systemic vascular resistance index decreased (-26%). Mean pulmonary arterial pressure (24%) as well as pulmonary capillary wedge pressure (27%) and central venous pressure (18%) were higher with adenosine compared to SNP. Adenosine also increased CSF and GCVF (108% and 103%, respectively) without altering the CSF/GCVF flow ratio compared to SNP. Furthermore, adenosine increased the coronary oxygen content (51%) and decreased the arterio-great cardiac vein oxygen content difference (-48%) without changing regional myocardial oxygen consumption, indicating a more pronounced hyperkinetic myocardial circulation compared to SNP. In addition, adenosine infusion decreased arterial PO2 (-11%) and increased the intrapulmonary shunt fraction (57%). The PR interval time of the electrocardiogram was prolonged (12%) and the ST segment was more depressed during adenosine infusion compared to SNP.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
103.
K. Mizutani 《Journal of Materials Science》1993,28(8):2178-2182
Transparent epoxy resins modified with liquid chloroprene rubber (LCR), containing in a category of rubber-toughened resin were found. Transparency and toughness characterization of the modified epoxy resins were investigated as a function of LCR content. Epoxy resins modified with 0–10 vol % LCR showed complete phase-separation microstructure. However, these modified resins were transparent, because the refractive index of LCR was compatible with that of the epoxy resin matrix at room temperature. On the other hand, it was observed that above 10 vol % LCR, a certain amount of LCR dissolved into the epoxy matrix. In this case, the glass transition temperature decreased with increasing LCR content. It was also found that the critical stress intensity factor, K
c, of the modified epoxy resins exhibited a maximum between 10 and 15 vol % LCR. 相似文献
104.
Translated from Izmeritel'naya Tekhnika, No. 3, pp. 40–42, March, 1993. 相似文献
105.
P. S. Theocaris N. P. Andrianopoulos S. K. Kourkoulis 《Journal of Materials Science》1993,28(16):4510-4514
The variation of the dynamic elastic modulus in the immediate vicinity of the tip of the running crack was studied through an iterative procedure, based on the theoretical expressions for the stress-field components and the experimental relation between strain rate and elastic modulus. It was found that the elastic modulus varied strongly around the tip of the crack, both in radial and polar sense. Also it was observed that the polar distribution of the elastic modulus presented clear off-axis extrema in directions that were in good agreement with experimentally measured branching angles, thus indicating a possible relation between these two phenomena. 相似文献
106.
OBJECTIVE: To evaluate what nursing home medical directors actually do, what they and other nursing home personnel believe would be desirable to do, and what problems and deficiencies are perceived. DESIGN: Mail survey with follow-up telephone interview when necessary. SETTING: Forty-five nursing facilities in upstate New York. PARTICIPANTS: The medical directors, administrators, and directors of nursing of the 45 facilities. MEASUREMENTS: Inventory of what medical directors reported as to their actual activities and time spent, and of what they, the administrators, and the directors of nursing felt should be their responsibilities and activities under ideal circumstances. RESULTS: For part-time medical directors, self-reported time spent on medical directorship activities averaged 12 hours per month; of all directors, 45% spent 8 hours or less per month. Proportion of time spent on various specific activities varied widely. There was general agreement that substantially more time should be spent, in particular, on evaluating and addressing problems of adequacy and quality of care, communicating with attending physicians about problems, and assisting with inservice training programs. CONCLUSIONS: To fill the role adequately, more time should be spent by many part-time medical directors, which will require greater financial commitment by facilities and reimbursement systems. Efforts need to made to better coordinate the expectations of medical directors and facility staff. 相似文献
107.
108.
109.
Surveyed 70 practicing attorneys and 150 law students to determine the extent to which they felt it was their responsibility to inform clients they referred for psychological testing about the testing process and about the validity scales on tests. Results showed that almost 50% of the attorneys and over 33% of the students believe that clients referred for testing always or usually should be informed of validity scales on tests. These results suggest that many test takers, particularly in forensic settings, may have information about validity scales that facilitates their giving biased responses without detection. Psychologists doing forensic evaluations should be alert to this possibility and should consider using more than one approach to detect response distortions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
110.
J Botling F Oberg H T?rm? P Tuohimaa M Bl?uer K Nilsson 《Canadian Metallurgical Quarterly》1996,7(9):1239-1249