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Hemodynamic consequences of right ventricular isolation: the contribution of the right ventricular free wall to cardiac performance 总被引:2,自引:0,他引:2
R J Damiano T Asano P K Smith T B Ferguson J L Cox 《The Annals of thoracic surgery》1988,46(3):324-330
Surgical isolation of the right ventricular free wall was performed in 10 dogs to evaluate both the hemodynamic effects of the procedure and the postoperative contribution of right ventricular free wall contraction to overall cardiac performance. Following the procedure, there was no significant differences in peak right ventricular systolic pressure, right atrial pressure, right ventricular stroke volume, or cardiac index. Cardiac index remained at preoperative levels over a wide range of filling pressures. However, there was a significant decrease in right ventricular stroke work (6.0 +/- 1.3 gm-m/m2 to 5.1 +/- 0.5 gm-m/m2; p less than 0.05). Pacing the isolated right ventricular free wall resulted in marked hemodynamic improvement compared with an electrically silent right ventricular free wall. Cardiac index increased from 1.7 +/- 0.2 L/min/m2 to 2.6 +/- 0.2 L/min/m2 (p less than 0.0005), and right ventricular stroke work went from 3.0 +/- 0.6 gm-m/m2 to 6.4 +/- 0.9 gm-m/m2 (p less than 0.0005). Right ventricular performance was also significantly related to the timing of right ventricular free wall contraction. Thus, the right ventricular free wall played an important role in the maintenance of normal cardiac hemodynamics. 相似文献
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D A Cottrell M L Henry T M O'Dorisio R J Tesi R M Ferguson K Osei 《Diabetic medicine》1992,9(5):438-443
We have previously shown that the loss of acute first phase insulin secretion precedes pancreas allograft rejection and development of glucose intolerance in Type 1 diabetic patients. In order to examine whether there is a progressive loss of phases of insulin secretion and beta-cell function in technically successful pancreas transplants during the first year, we measured glucose, insulin, and C-peptide responses to physiological (mixed meal) and pharmacological (IV glucose and IV glucagon) stimulation in 27 glucose-tolerant, insulin-independent allograft recipients at 3, 6, and 12 months. Mean +/- SE fasting serum glucose levels were normalized throughout the study period. Postprandial serum glucose profiles tended to increase by 12 months compared to 3 and 6 months, although peak glucose levels were not statistically different. Following pancreas transplantation, basal serum insulin levels were high at 3 months (163 +/- 17 pM), 6 months (165 +/- 22 pM), and 12 months (248 +/- 54 pM, p = NS) in the Type 1 diabetic pancreas allograft recipients when compared to normal (25 +/- 3 pM). We observed slight elevations in postprandial insulin and C-peptide profiles at 12 months compared to 3 and 6 months. Following IV glucose and glucagon stimulation, serum insulin and C-peptide levels as well as phases of insulin release did not differ over the 12-month study period. Similarly, the glucose decay constant (KG) was nearly identical at 3, 6, and 12 months. In summary, 1 year following successful whole cadaveric, heterotopic pancreas transplantation in Type 1 diabetic recipients, fasting serum glucose remains normalized, while postprandial glucose tends to rise.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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C R Miles P A Blombery N Sacharias J W Stubbe C J Bass I A Ferguson D S Rosengarten K E Stuchbery 《The Australian and New Zealand journal of surgery》1986,56(5):417-421
Between August 1983 and January 1985, 20 patients aged 33-77 years, with occluded lower limb bypass grafts, were on 23 occasions treated with streptokinase via intra-arterial infusion. Streptokinase (5000 units/h) was effective in clearing occluded grafts in 15 patients on 16 occasions. The median duration of occlusion in these patients was 5 days and the median duration of streptokinase infusions was 24 h. Completion angiography following streptokinase thrombolysis revealed five graft stenoses and 12 outflow stenoses or occlusions. In two grafts no cause for graft failure could be identified. These results permitted the surgeon to make an accurate pre-operative assessment of the definitive therapy required to ensure graft patency. 相似文献
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N G Forouhi D Merrick E Goyder B A Ferguson J Abbas K Lachowycz S H Wild 《Diabetic medicine》2006,23(2):189-197
AIMS: To estimate the total prevalence of diabetes mellitus (diagnosed and undiagnosed) at national, regional and local level in England to support health-care planning and delivery. METHODS: An epidemiological model was constructed by applying age-sex-ethnic-specific reference prevalence rates from epidemiological studies to resident populations (2001 census) of England at national, regional, and local authority/Primary Care Trust levels. RESULTS: Estimated prevalence of total diabetes for all persons in England was 4.41% in 2001, equating to 2 168 000 persons. Type 2 diabetes was estimated to affect 2 002 000 persons (92.3%) and Type 1 diabetes 166 000 persons (7.7%). Diabetes prevalence was estimated to be higher in women (5.17%) than men (3.61%). People from ethnic minority groups had higher crude prevalence than White Europeans (4.29, 5.69, 6.63 and 2.13% among White Europeans, Black African/Caribbeans, South Asians and 'other' groups, respectively). Prevalence increased sharply with age (0.33, 3.37 and 13.92%, respectively, in those aged 0-29, 30-59 and 60+ years). The model allows use of user-defined population denominator estimates to derive numbers and prevalence of people with diabetes for a given local population group, such as at ward or general practice level. CONCLUSIONS: Self-reported diabetes prevalence estimates from community surveys underestimate the true burden of diabetes. The model can be used to derive the expected total prevalence of diabetes in health areas that lack reliable data to facilitate the implementation of the National Service Framework for diabetes. It will also allow estimates of future diabetes prevalence to be derived, and can potentially be used for prevalence estimates in all of the UK. 相似文献
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Résumé Le kiwi est par définition une baie : il possède un grand nombre de graines incluses dans une chair comestible. Le kiwi a
pour nom latinActinidia et il y a principalement deux espèces d’Actinidia :Actinidia chinensis etActinidia deliciosa. Le kiwi n’est pas seulement un fruit agréable à manger, il est aussi une source exceptionnellement riche en diverses vitamines.
Le kiwi est notamment très riche en vitamine C puisqu’il en contient 50 % plus qu’une orange. Le kiwi contient aussi des vitamines
K et E. Il est également une source non négligeable de potassium et de folate. Il contient aussi un laxatif, qui plus est,
puissant. La qualité nutritionnelle du kiwi ne s’altère pas même pendant une longue durée de stockage pour certains nutriments.
Cependant, les risques de réponse allergique ne doivent pas être sous-estimés.
The kiwifruit is, by definition, a berry: it has a large number of seeds embedded in fleshy, edible tissue. The Latin name
of kiwifruit isActinidia and there are two main species ofActinidia that are commercially important:Actinidia chinensis andActinidia deliciosa.
Kiwifruit are not only enjoyable to eat. They are exceptionally good sources of vitamin C and they are also excellent sources
of potassium and folate and possibly of vitamin E and vitamin K. They contain a most effective laxative. There is very little,
if any, loss of nutritional quality during storage. However, the risks from the allergic response to kiwifruit should not
be underestimated.
相似文献
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