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Dante E. Manyari William J. Kostuk Paul Purves 《The American journal of cardiology》1983,52(1):159-162
To assess the effects of pericardial effusion on ventricular performance and volumes, electrocardiographically gated blood pool cardiac scintigraphy was performed immediately before and after 14 pericardiocenteses in 10 patients, 7 men and 3 women, aged 28 to 73 years (mean 50). Cardiac tamponade was present in 5 patients. After removal of 140 to 1,100 ml of pericardial fluid (527 ± 305 ml [mean ± standard deviation]), left ventricular (LV) ejection fraction increased from 63 ± 5 to 64 ± 4% (p > 0.05) and right ventricular (RV) ejection fraction decreased from 47 ± 4 to 46 ± 2% (p > 0.05). LV end-diastolic and end-systolic volumes increased (p < 0.01) by 28 and 33%, and RV volumes by 40 and 43%, respectively. There were 8 patients with normal LV function (ejection fraction > 60 %) and 6 patients with subnormal LV function. Changes in ejection fraction were nonsignificant in the 4 subgroups. LV end-diastolic volume changes were more marked (p < 0.01) in patients with cardiac tamponade (+ 56%) than in those without tamponade (+ 17%), and in those with normal LV function (+ 36%) than in those with subnormal LV function (+ 21%). RV end-diastolic volume increased more markedly (p < 0.05) in patients with tamponade (+ 72%) than in those without tamponade (+ 23%), but were similar in patients with normal (+ 38% ) and abnormal (+ 43% ) LV function. After pericardiocentesis, RV volume increased more markedly than did LV volume. Thus, hemodynamic and clinical improvement after pericardiocentesis may be related only to an increase in stroke volume. RV and LV ejection fraction, a measure of myocardial contractility, was not affected significantly by the presence of pericardial effusion, even in those patients who had cardiac tamponade. 相似文献
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Scott-Douglas NW Robinson VJ Smiseth OA Wright CI Manyari DE Smith ER Tyberg JV 《The Canadian journal of cardiology》2002,18(5):515-522
BACKGROUND: Changes in intestinal vascular capacitance during acute volume loading and hemorrhage have not been described. OBJECTIVES: To determine the effects of volume loading and hemorrhage on the intestinal vascular pressure-volume relationship and cardiac output. PATIENTS AND METHODS: In 11 alpha-chloralose-anesthetized dogs, a pneumatic portal venous constrictor and catheter were positioned to increase and measure portal venous pressure (Ppv), respectively. Relative changes in intestinal blood volume (IBV) were determined by blood-pool scintigraphy and expressed as the percentage change from control values (taken as 100%). Ppv-IBV relationships were constructed by graded portal vein constriction. RESULTS: IBV and cardiac output increased by 60 6% and 178 48%, respectively, and Ppv increased from 5.8 0.9 mmHg to 13.2 1.8 mmHg after initial volume loading (40 mL/kg of an isotonic glucose-saline solution over 7 min). IBV gradually decreased and reached near-control values after 75 min. In seven dogs, hemorrhage (sufficient to decrease mean aortic pressure by 56 4%) decreased IBV and cardiac output to 88 4% and 52 3% of control values, respectively, and Ppv decreased to 3.2 0.8 mmHg. CONCLUSIONS: A sigmoid function curve defined the relationship between cardiac output and IBV. Cardiac output remained constant over a wide range (between approximately 95% and 135% of control IBV). Outside this range, insufficient dilation or constriction resulted in a marked increase or decrease in venous pressures and cardiac output. These data indicate that vasculature capacitance modulates cardiac output during acute volume loading and hemorrhage, thereby maintaining cardiac output relatively constant over a wide range of total vascular blood volume. 相似文献
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Sheree L. Toth Dante Cicchetti Jenny MacFie Angeline Maughan Kirsten Vanmeenen 《Attachment & human development》2013,15(3):271-305
This study examined narrative representations of parents and of self, as well as child behavior during the assessment, in maltreated (N = 56) and demographically comparable non-maltreated (N = 37) pre-school-aged children in a one-year longitudinal study. Maltreated children evidenced more negative representations of parents and of self at Time 2, including the juxtaposition of both a negative and a grandiose self. Over time there was a marginal interaction such that maltreated children portrayed fewer disciplining parent representations and nonmaltreated children portrayed more. Also over time, maltreated children portrayed marginally more grandiose self-representations and nonmaltreated children fewer. Furthermore, maltreated children demonstrated less responsivity to the examiner over time and nonmaltreated children demonstrated more. The deleterious effects of maltreatment on representations of self and of others, especially as development proceeds, are discussed, and the importance of providing attachment-informed intervention prior to the consolidation of these negative representations is highlighted. 相似文献
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Vicente Colomer-Romero Dante Rogiest Juan Antonio García-Manrique Jose Enrique Crespo 《Materials》2020,13(24)
Bio- and green composites are mainly used in non-structural automotive elements like interior panels and vehicle underpanels. Currently, the use of biocomposites as a worthy alternative to glass fibre-reinforced plastics (GFRPs) in structural applications still needs to be fully evaluated. In the current study, the development of a suited biocomposites started with a thorough review of the available raw materials, including both reinforcement fibres and matrix materials. Based on its specific properties, hemp appeared to be a very suitable fibre. A similar analysis was conducted for the commercially available biobased matrix materials. Greenpoxy 55 (with a biocontent of 55%) and Super Sap 100 (with a biocontent of 37%) were selected and compared with a standard epoxy resin. Tensile and three-point bending tests were conducted to characterise the hemp-based biocomposite. 相似文献
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Priscilla Soares Elizângela Silva de Brito Fernando Paiva Dante Pavan Lúcio André Viana 《Parasitology research》2014,113(12):4499-4503
The study objectives were to characterize the morphology of the parasitic forms and describe the prevalence and intensity of Haemogregarina spp. in a population of the turtle Podocnemis unifilis as well as to examine the relationships between parasitism and turtle variables such as gender, size, and weight. Samples were taken in the Tapajós and Jamanxim rivers, Itaituba, Pará state, Brazil. Blood was collected from the tail vein of 72 P. unifilis specimens, including 35 males, 36 females, and one unsexed juvenile. The prevalence of Haemogregarina spp. was 98 % (n?=?71). The mean parasite intensity of Haemogregarina spp. was 118 (1–582) parasites/2000 blood cells (6 %). There was no significant difference in the mean parasite intensity between male (137.68?±?121.8, n?=?35) and female turtles (101.42?±?123.59, n?=?35). There was no relationship between parasite intensity and carapace length. Although the relationship between parasite intensity and host body weight was significant, the relationship was weak. This is the first study on Haemogregarina parasitism with a relatively high number of turtles in Brazil. 相似文献
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